Use of Medicare data to identify coronary heart disease outcomes in the Women's Health Initiative

Impact of design characteristics among studies comparing coronary computed tomography angiography to noninvasive functional testing in chronic coronary syndromes

BACKGROUND

Coronary computed tomography angiography (CCTA) is widely adopted to detect obstructive coronary artery disease (CAD) in patients with chronic coronary syndromes (CCS). However, it is unknown to which extent study-specific characteristics yield different conclusions.

METHODS

We summarized non-randomized and randomized studies comparing CCTA and noninvasive functional testing for CCS with information on the outcome of myocardial infarction (MI). We evaluated the differential effect according to study characteristics using random-effect meta-analysis with Hartung-Knapp-Sidik-Jonkman adjustments.

RESULTS

Fifteen studies (8 non-randomized, 7 randomized) were included. CCTA was associated with decrease in relative (odds ratio (OR) 0.54, 95%CI 0.47 to 0.62, P < .001) and absolute MI risk (risk difference (RD) -0.4%, 95%CI -0.6 to -0.1, P = .005). The results remained consistent among the non-randomized (RD -0.4%, 95%CI -0.7 to -0.1, P=.029), but not among the randomized trials where there was no difference in the observed risk (RD 0.2%, 95%CI -0.6 to 0.1, P = .158). CCTA was not associated with MI reduction in studies with clinical outcome definition (OR 0.77, 95%CI 0.41 to 1.44, P = .212), research driven follow-up (OR 0.54, 95%CI 0.24 to 1.21, P = .090), central event assessment (OR 0.63, 95%CI 0.21 to 1.86, P = .207), outcome adjudication (OR 0.74, 95%CI 0.24 to 2.23, P = .178), or at low-risk of bias (OR 0.74, 95%CI 0.24 to 2.23, P = .178).

CONCLUSIONS

Among studies of any design, CCTA was associated with lower risk of MI in CCS compared to noninvasive functional testing. This benefit was diminished among studies with clinical outcome definition, central outcome assessment/adjudication or at low-risk of bias.

Association of Premature Menopause With Risk of Abdominal Aortic Aneurysm in the Women's Health Initiative

OBJECTIVE

To determine if premature menopause and early menarche are associated with increased risk of AAA, and to explore potential effect modification by smoking history.

SUMMARY OF BACKGROUND DATA

Despite worse outcomes for women with AAA, no studies have prospectively examined sex-specific risk factors, such as premature menopause and early menarche, with risk of AAA in a large, ethnically diverse cohort of women.

METHODS

This was a post-hoc analysis of Women's Health Initiative participants who were beneficiaries of Medicare Parts A&B fee-for-service. AAA cases and interventions were identified from claims data. Follow-up period included Medicare coverage until death, end of follow-up or end of coverage inclusive of 2017.

RESULTS

Of 101,119 participants included in the analysis, the mean age was 63 years and median follow-up was 11.3 years. Just under 10,000 (9.4%) women experienced premature menopause and 22,240 (22%) experienced early men-arche. Women with premature menopause were more likely to be overweight, Black, have >20 pack years of smoking, history of cardiovascular disease, hypertension, and early menarche. During 1,091,840 person-years of follow-up, 1125 women were diagnosed with AAA, 134 had premature menopause (11.9%), 93 underwent surgical intervention and 45 (48%) required intervention for ruptured AAA. Premature menopause was associated with increased risk of AAA [hazard ratio 1.37 (1.14, 1.66)], but the association was no longer significant after multivariable adjustment for demographics and cardiovascular disease risk factors. Amongst women with ≥20 pack year smoking history (n = 19,286), 2148 (11.1%) had premature menopause, which was associated with greater risk of AAA in all models [hazard ratio 1.63 (1.24, 2.23)]. Early menarche was not associated with increased risk of AAA.

CONCLUSIONS

This study finds that premature menopause may be an important risk factor for AAA in women with significant smoking history. There was no significant association between premature menopause and risk of AAA amongst women who have never smoked. These results suggest an opportunity to develop strategies for better screening, risk reduction and stratification, and outcome improvement in the comprehensive vascular care of women.

Women's Health Initiative Strong and Healthy (WHISH): A pragmatic physical activity intervention trial for cardiovascular disease prevention

BACKGROUND

National guidelines promote physical activity to reduce cardiovascular disease (CVD); yet, no RCT has tested the effectiveness of physical activity as the sole intervention for primary CVD prevention in older adults. The Women's Health Initiative (WHI) Strong and Healthy (WHISH) trial, a pragmatic trial embedded in the WHI-Extension Study (ES), is testing whether increasing physical activity and decreasing sedentary behavior will reduce major CV events in older women.

METHODS

The randomized consent design was used to assign 49,331 women (aged 68-99 years in 2015) who had consented to ongoing WHI-ES follow-up and for whom CV outcomes were available through WHI-ES procedures (N = 18,985) and/or linkage to the Centers for Medicare and Medicaid Services (N = 30,346) to a physical activity (PA) intervention designed to promote national recommendations (N = 24,657) or "usual activity" comparison (N = 24,674). Women assigned to the intervention provided passive consent to receive the intervention and provide data. A multi-component PA intervention is delivered by seasonal (quarterly) newsletters with targeted inserts (lower, middle, higher) based on self-reported levels of physical functioning (PF) and physical activity; monthly motivational telephone messages; monthly emails; a website; and contact with staff, as requested. Major CV events, myocardial infarction (MI), stroke, or CVD death, collected annually through WHI-ES, comprise the primary outcome. Hip fracture and non-CVD death are primary safety outcomes. Intention-to-treat analyses in all randomized participants will include 8 years of follow-up.

CONCLUSION

Determining whether increased physical activity and decreased sedentary behavior reduce major CV events in older women is of major public health significance.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.govidentifier:NCT02425345.

Completeness of cohort-linked U.S. Medicare data: An example from the Agricultural Health Study (1999–2016)

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We describe linked U.S. Medicare claims data in the Agricultural Health Study.

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Incomplete claims data were related to geographic, demographic, and health.

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We saw potential informative missingness by pesticide use and mortality.

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Incomplete data in Medicare-linked cohorts may impact sample size and validity.

Medicare Fee for Service (FFS) claims data, including inpatient (Part A) and outpatient (Part B) services, provide a valuable resource for research on older adults (≥65 year) in linked U.S. cohorts. Here we describe our experience linking the Agricultural Health Study cohort, including 47,501 licensed pesticide applicators and spouses from North Carolina (NC) and Iowa (IA) to Medicare claims data from 1999 to 2016. Given increased Part C (i.e., managed care/Medicare Advantage) enrollment during this period, and a resulting lack of available Part C claims data prior to 2015, we also explored potential for informative missingness. We compared those with partial or limited/no FFS to those with complete FFS coverage (i.e., ≥11 months per year parts AB, but not C, throughout Medicare enrollment) in relation to baseline farm size, general pesticide use, and mortality, in logistic regression models adjusted for age, sex, race, education, and smoking, and stratified by state. While 46,689 participants (98%) were linked to Medicare IDs, only 33,487 (70%) had complete FFS, 9353 (20%) had partial FFS (≥1 year FFS but not complete), and 3849 (8%) had limited/no FFS (Part A or Part C-only). Incomplete FFS was more common in NC, mostly due to Part C, and was associated with farm characteristics, pesticide use, and mortality. These findings indicate that, in addition to reduced sample size in analyses limited to complete FFS, missingness may not be random. The potential impact of incomplete FFS data and changes in coverage type need to be considered when planning linked analyses and interpreting results.

Outcomes Associated With Peripheral Artery Disease in Myocardial Infarction With Cardiogenic Shock

BACKGROUND

Mortality rates for patients presenting with acute myocardial infarction (AMI) and cardiogenic shock (CS) remain high despite advances in revascularization strategies and mechanical circulatory support (MCS) devices.

OBJECTIVES

This study sought to elucidate the association between comorbid lower extremity peripheral artery disease (PAD) and outcomes in CS and AMI.

METHODS

PAD status was defined in Medicare beneficiaries hospitalized with CS and AMI from October 1, 2015 to June 30, 2018. Primary outcomes ascertained through December 31, 2018 included in- and out-of-hospital mortality. Secondary outcomes included bleeding, amputation, stroke, and lower extremity revascularization. Multivariable regression models with adjustment for confounders were used to estimate risk. Subgroup analyses included patients treated with MCS and those who underwent coronary revascularization.

RESULTS

Among 71,690 patients, 5.9% (N = 4,259) had PAD. Mean age was 77.8 ± 7.9 years, 58.7% were male, and 84.3% were White. Cumulative in-hospital mortality was 47.2%, with greater risk among those with PAD (56.3% vs 46.6% without PAD; adjusted OR: 1.50; 95% CI: 1.40-1.59). PAD patients also had greater risk of in-hospital amputation (1.6% vs 0.2%; adjusted OR: 7.0; 95% CI: 5.26-9.37) and out-of-hospital mortality (67.9% vs 40.7%; adjusted HR: 1.78; 95% CI: 1.67-1.90). MCS was less frequently utilized in PAD patients (21.5% vs 38.6% without PAD; P < 0.001) and was associated with higher mortality, need for lower extremity revascularization, and amputation risk. Findings were consistent in patients who underwent coronary revascularization.

CONCLUSIONS

Among patients presenting with AMI and CS, PAD was associated with worse limb outcomes and survival. In addition to lower MCS utilization rates, those with PAD who received MCS had increased mortality, lower extremity revascularization, and amputation rates.

Metastatic Breast Cancer Recurrence after Bone Fractures

Simple Summary

Bone fractures bear potential risk to promote metastatic relapse in breast cancer. We conducted a population-based cohort study of 84,300 breast cancer patients diagnosed between January 2015 and November 2019. Bone fracture after breast cancer diagnosis was associated with an increased metastasis risk. Fractures may pose an increased risk to developing metastasis. Potential clinical implications for cancer patients are in support of fall prevention programs.

Abstract

Experimental studies suggest that bone fractures result in the release of cytokines and cells that might promote metastasis. Obtaining observational data on bone fractures after breast cancer diagnoses related to distant breast cancer recurrence could help to provide first epidemiological evidence for a metastasis-promoting effect of bone fractures. We used data from the largest German statutory health insurance fund (Techniker Krankenkasse, Hamburg, Germany) in a population-based cohort study of breast cancer patients with ICD-10 C50 codes documented between January 2015 and November 2019. The risk of metastasis overall, regional, distant non-bone or bone metastasis related to a fracture was modeled by an adjusted discrete time-to-event analysis with time-dependent exposure. Of 154,000 breast cancer patients, 84,300 fulfilled the inclusion criteria and had a follow-up time of more than half a year. During follow-up, fractures were diagnosed in 13,579 (16.1%) patients. Metastases occurred in 7047 (8.4%) patients; thereof 1544 had affected regional lymph nodes only and 5503 distant metastases. Fractures demonstrated a statistically significant association with subsequent metastasis overall (adjusted HR 1.12, 95% CI 1.04, 1.20). The highest risk for metastasis was observed in patients with subsequent bone metastasis (adjusted HR 1.18, 95% CI 1.05, 1.34), followed by distant non-bone metastasis (adjusted HR 1.16, 95% CI 1.07, 1.26) and lymph node metastasis (adjusted HR 1.08, 95% CI 0.97, 1.21).

Comparison of the Accuracy and Completeness of Records of Serious Vascular Events in Routinely Collected Data vs Clinical Trial-Adjudicated Direct Follow-up Data in the UK: Secondary Analysis of the ASCEND Randomized Clinical Trial

Importance

Routinely collected data could substantially decrease the cost of conducting trials.

Objective

To assess the accuracy and completeness of UK routine data for ascertaining serious vascular events (SVEs) compared with adjudicated follow-up data.

Design, Setting, and Participants

This was a secondary analysis of a randomized clinical trial. From June 24, 2005, to July 28, 2011, the ASCEND (A Study of Cardiovascular Events in Diabetes) primary prevention trial used mail-based methods to randomize people with diabetes without evidence of atherosclerotic vascular disease using a 2 × 2 factorial design to aspirin and/or ω-fatty acids vs matching placebo in the UK. Direct participant mail-based follow-up was the main source of outcome data, with more than 90% of the primary outcome events undergoing adjudication. Follow-up was completed on July 31, 2017. In parallel, more than 99% of participants were linked to routinely collected hospital admission and death registry data (ie, routine data), enabling post hoc randomized comparisons of different sources of outcome data (conducted from September 1, 2018, to October 1, 2021).

Interventions

Random allocation to 100 mg of aspirin once daily vs matching placebo and separately to 1 g of ω-3 fatty acids once daily vs placebo.

Main Outcomes and Measures

The primary outcome consisted of SVEs (a composite of nonfatal myocardial infarction, ischemic stroke, transient ischemic attack [TIA], or vascular death, excluding hemorrhagic stroke).

Results

A total of 15 480 participants were randomized (mean [SD] age, 63 [9] years; 9684 [62.6%] men) and followed up for a mean (SD) of 7.4 (1.8) years. For SVEs, agreement between adjudicated direct follow-up and routine data sources was strong (1401 vs 1127 events; κ = 0.78 [95% CI, 0.76-0.80]; sensitivity, 72.0% [95% CI, 69.7%-74.4%]; specificity, 99.2% [95% CI, 99.0%-99.3%]), and sensitivity improved for SVEs excluding transient ischemic attack (1129 vs 1026 events; sensitivity, 80.6% [95% CI, 78.3%-82.9%]). Rate ratios for the aspirin-randomized comparison for adjudicated direct follow-up vs follow-up solely through routine data alone were 0.88 (95% CI, 0.79-0.97) vs 0.91 (95% CI, 0.81-1.02) for the primary outcome and 0.92 (95% CI, 0.82-1.03) vs 0.91 (95% CI, 0.80-1.02) for SVEs excluding TIA. Results were similar for the ω-3 fatty acid comparison, and adjudication did not seem to markedly change rate ratios.

Conclusions and Relevance

Post hoc analyses of the ASCEND trial suggest that routinely collected hospital admission and death registry data in the UK could be used as the sole method of follow-up for myocardial infarction, ischemic stroke resulting in hospitalization, vascular death, and arterial revascularization in primary prevention cardiovascular trials, without the need for verification by clinical adjudication.

Ascertaining Nonfatal Endpoints in Clinical Trials: Central Adjudication Versus Patient Insurance Claims

BACKGROUND

The 21st Century Cures Act allows the US Food and Drug Administration (FDA) to utilize real-world data (RWD) to create real-world evidence (RWE) for new indications or post approval study requirements. We compared central adjudication with two insurance claims data sources to understand how endpoint accuracy differences impact RWE results.

METHODS

We developed a decision analytic model to compare differences in efficacy (all-cause death, stroke and myocardial infarction) and safety (bleeding requiring transfusion) results for a simulated acute coronary syndrome antiplatelet therapy clinical trial. Endpoint accuracy metrics were derived from previous studies that compared centrally-adjudicated and insurance claims-based clinical trial endpoints.

RESULTS

Efficacy endpoint results per 100 patients were similar for the central adjudication model (intervention event rate, 11.3; control, 13.7; difference, 2.4) and the prospective claims data collection model (intervention event rate, 11.2; control 13.6; difference, 2.3). However, the retrospective claims linking model's efficacy results were larger (intervention event rate, 14.6; control, 18.0; difference, 3.4). True positive event rate results (intervention, control and difference) for both insurance claims-based models were less than the central adjudication model due to false negative events. Differences in false positive event rates were responsible for differences in efficacy results for the two insurance claims-based models.

CONCLUSION

Efficacy endpoint results differed by data source. Investigators need guidance to determine which data sources produce regulatory-grade RWE.

Accuracy of Cardiovascular Trial Outcome Ascertainment and Treatment Effect Estimates from Routine Health Data: A Systematic Review and Meta-Analysis

BACKGROUND

Registry-based randomized controlled trials allow for outcome ascertainment using routine health data (RHD). While this method provides a potential solution to the rising cost and complexity of clinical trials, comparative analyses of outcome ascertainment by clinical end point committee (CEC) adjudication compared with RHD sources are sparse. Among cardiovascular trials, we set out to systematically compare the incidence of cardiovascular events and estimated randomized treatment effects ascertained from RHD versus traditional clinical evaluation and adjudication.

METHODS

We searched MEDLINE (1976 to August 2020) for studies where outcome ascertainment was performed by both RHD and CEC adjudication to compare the incidence of cardiovascular events and treatment effects. We derived ratios of hazard ratios to compare treatment effects from RHD and CEC adjudication. We pooled ratios of hazard ratios using an inverse variance random-effects meta-analysis.

RESULTS

Nine studies (1988-2020; 32 156 patients) involving 10 randomized control trials compared outcome ascertainment with RHD and CEC in patients with or at risk of cardiovascular disease. There was a high degree of agreement and interrater reliability between CEC and RHD outcome determination for all-cause mortality (agreement percentage: 98.4%-100% and κ: 0.95-1.0) and cardiovascular mortality (agreement percentage: 97.8%-99.9% and κ: 0.66-0.99). For myocardial infarction, the κ values ranged from 0.67-0.98, and for stroke the values ranged from 0.52-0.89. In contrast, the κ value for peripheral artery disease was low (κ: 0.27). There was little difference in the randomized treatment effect derived from CEC and RHD ascertainment of events based on the ratios of hazard ratio, with pooled ratios of hazard ratios ranging from 0.93 (95% CI, 0.63-1.39) for cardiovascular mortality to 1.27 (95% CI, 0.67-2.41) for stroke.

CONCLUSIONS

Clinical outcome ascertainment using retrospectively acquired RHD displayed high levels of agreement with CEC adjudication for identifying all-cause mortality and cardiovascular outcomes. Importantly, cardiovascular treatment effects in randomized control trials determined from RHD and CEC resulted in similar point estimates. Overall, our review supports the use of RHD as a potential alternative source for clinical outcome ascertainment in cardiovascular trials. Validation studies with prospectively planned linkage are warranted.

Utilization of Medical Codes for Hypotension in Shock Patients: A Retrospective Analysis

Purpose

To evaluate the utilization of hypotension diagnosis codes by shock type and year in known hypotensive patients.

Patients and Methods

Retrospective analysis of the Medicare fee-for-service claims database. Patients with a shock diagnosis code between 2011 and 2017 were identified using the International Classification of Diseases, Ninth and Tenth Revision, Clinical Modification (ICD-9-CM and ICD-10-CM). Based on specific ICD codes corresponding to each shock type, patients were classified into four mutually exclusive cohorts: cardiogenic shock, hypovolemic shock, septic shock, and other/unspecified shock. Annual proportion and counts of cases with at least one hypotension ICD code for each shock cohort were generated to produce 7-year medical code utilization trends. A Cochran-Armitage test for trend was performed to evaluate the statistical significance.

Results

A total of 2,200,275 shock patients were analyzed, 13.3% (n=292,192) of which received a hypotension code. Hypovolemic shock cases were the most likely to receive a hypotension code (18.02%, n=46,544), while septic shock cases had the lowest rate (11.48%, n=158,348). The proportion of patients with hypotension codes for other cohorts were 18.0% (n=46,544) for hypovolemic shock and 16.9% (n=32,024) for other/unspecified shock. The presence of hypotension codes decreased by 0.9% between 2011 and 2014, but significantly increased from 10.6% in 2014 to 17.9% in 2017 (p <0.0001, Z=−105.05).

Conclusion

Hypotension codes are remarkably underutilized in known hypotensive patients. Patients, providers, and researchers are likely to benefit from improved hypotension coding practices.

Women's Health Initiative Strong and Healthy Pragmatic Physical Activity Intervention Trial for Cardiovascular Disease Prevention: Design and Baseline Characteristics

BACKGROUND

National guidelines promote physical activity to prevent cardiovascular disease (CVD), yet no randomized controlled trial has tested whether physical activity reduces CVD.

METHODS

The Women's Health Initiative (WHI) Strong and Healthy (WHISH) pragmatic trial used a randomized consent design to assign women for whom cardiovascular outcomes were available through WHI data collection (N = 18 985) or linkage to the Centers for Medicare and Medicaid Services (N30 346), to a physical activity intervention or "usual activity" comparison, stratified by ages 68-99 years (in tertiles), U.S. geographic region, and outcomes data source. Women assigned to the intervention could "opt out" after receiving initial physical activity materials. Intervention materials applied evidence-based behavioral science principles to promote current national recommendations for older Americans. The intervention was adapted to participant input regarding preferences, resources, barriers, and motivational drivers and was targeted for 3 categories of women at lower, middle, or higher levels of self-reported physical functioning and physical activity. Physical activity was assessed in both arms through annual questionnaires. The primary outcome is major cardiovascular events, specifically myocardial infarction, stroke, or CVD death; primary safety outcomes are hip fracture and non-CVD death. The trial is monitored annually by an independent Data Safety and Monitoring Board. Final analyses will be based on intention to treat in all randomized participants, regardless of intervention engagement.

RESULTS

The 49 331 randomized participants had a mean baseline age of 79.7 years; 84.3% were White, 9.2% Black, 3.3% Hispanic, 1.9% Asian/Pacific Islander, 0.3% Native American, and 1% were of unknown race/ethnicity. The mean baseline RAND-36 physical function score was 71.6 (± 25.2 SD). There were no differences between Intervention (N = 24 657) and Control (N = 24 674) at baseline for age, race/ethnicity, current smoking (2.5%), use of blood pressure or lipid-lowering medications, body mass index, physical function, physical activity, or prior CVD (10.1%).

CONCLUSION

The WHISH trial is rigorously testing whether a physical activity intervention reduces major CV events in a large, diverse cohort of older women. Clinical Trials Registration Number: NCT02425345.

Prognosis of Claims- Versus Trial-Based Ischemic and Bleeding Events Beyond 1 Year After Coronary Stenting

Background It is unknown whether clinical events identified with administrative claims have similar prognosis compared with trial-adjudicated events in cardiovascular clinical trials. We compared the prognostic significance of claims-based end points in context of trial-adjudicated end points in the DAPT (Dual Antiplatelet Therapy) study. Methods and Results We matched 1336 patients aged ≥65 years who received percutaneous coronary intervention in the DAPT study with the CathPCI registry linked to Medicare claims. We compared death at 21 months post-randomization using Cox proportional hazards models among patients with ischemic events (myocardial infarction or stroke) and bleeding events identified by: (1) both trial adjudication and claims; (2) trial adjudication only; and (3) claims only. A total of 47 patients (3.5%) had ischemic events identified by both trial adjudication and claims, 24 (1.8%) in trial adjudication only, 15 (1.1%) in claims only, and 1250 (93.6%) had no ischemic events, with annualized unadjusted mortality rates of 12.8, 5.5, 14.9, and 1.26 per 100 person-years, respectively. A total of 44 patients (3.3%) had bleeding events identified with both trial adjudication and claims, 13 (1.0%) in trial adjudication only, 65 (4.9%) in claims only, and 1214 (90.9%) had no bleeding events, with annualized unadjusted mortality rates of 11.0, 16.8, 10.7, and 0.95 per 100 person-years, respectively. Among patients with no trial-adjudicated events, patients with events in claims only had a high subsequent adjusted mortality risk (hazard ratio (HR) ischemic events: 31.5; 95% CI, 8.9‒111.9; HR bleeding events 23.9; 95% CI, 10.7‒53.2). Conclusions In addition to trial-adjudicated events, claims identified additional clinically meaningful ischemic and bleeding events that were prognostically significant for death.

Comparability of Event Adjudication Versus Administrative Billing Claims for Outcome Ascertainment in the DAPT Study: Findings From the EXTEND-DAPT Study

BACKGROUND

Data from administrative claims may provide an efficient alternative for end point ascertainment in clinical trials. However, it is uncertain how well claims data compare to adjudication by a clinical events committee in trials of patients with cardiovascular disease.

METHODS

We matched 1336 patients ≥65 years old who received percutaneous coronary intervention in the DAPT (Dual Antiplatelet Therapy) Study with the National Cardiovascular Data Registry CathPCI Registry linked to Medicare claims as part of the EXTEND (Extending Trial-Based Evaluations of Medical Therapies Using Novel Sources of Data) Study. Adjudicated trial end points were compared with Medicare claims data with International Classification of Diseases, Ninth Revision codes from inpatient hospitalizations using time-to-event analyses, sensitivity, specificity, positive predictive value, negative predictive value, and kappa statistics.

RESULTS

At 21-month follow-up, the cumulative incidence of major adverse cardiovascular and cerebrovascular events (combined mortality, myocardial infarction, and stroke) was similar between trial-adjudicated events and claims data (7.9% versus 7.2%, respectively; P=0.50). Bleeding rates were lower using adjudicated events compared with claims (5.0% versus 8.6%, respectively; P<0.001). The sensitivity and positive predictive value of comprehensive billing codes for identifying adjudicated events were 65.6% and 85.7% for myocardial infarction, 61.5% and 47.1% for stroke, and 76.8% and 39.3% for bleeding, respectively. Specificity and negative predictive value for all outcomes ranged from 93.7% to 99.5%. All 39 adjudicated deaths were identified using Medicare data. Kappa statistics assessing agreement between events for myocardial infarction, stroke, and bleeding were 0.73, 0.52, and 0.49, respectively.

CONCLUSIONS

Claims data had moderate agreement with adjudication for myocardial infarction and poor agreement but high specificity for bleeding and stroke in the DAPT Study. Deaths were identified equivalently. Using claims data in clinical trials could be an efficient way to assess mortality among Medicare patients and may help detect other outcomes, although additional monitoring is likely needed to ensure accurate assessment of events.

High-Sensitivity Cardiac Troponin-Optimizing the Diagnosis of Acute Myocardial Infarction/Injury in Women (CODE-MI): Rationale and design for a multicenter, stepped-wedge, cluster-randomized trial

Despite evidence that high-sensitivity cardiac troponin (hs-cTn) levels in women are lower than in men, a single threshold based on the 99th percentile upper reference limit of the overall reference population is commonly used to diagnose myocardial infarction in clinical practice. This trial aims to determine whether the use of a lower female-specific hs-cTn threshold would improve the diagnosis, treatment, and outcomes of women presenting to the emergency department with symptoms suggestive of myocardial ischemia. METHODS/DESIGN: CODE-MI (hs-cTn-Optimizing the Diagnosis of Acute Myocardial Infarction/Injury in Women) is a multicenter, stepped-wedge, cluster-randomized trial of 30 secondary and tertiary care hospitals across 8 Canadian provinces, with the unit of randomization being the hospital. All adults (≥20 years of age) presenting to the emergency department with symptoms suggestive of myocardial ischemia and at least 1 hs-cTn test are eligible for inclusion. Over five, 5-month intervals, hospitals will be randomized to implement lower female hs-cTn thresholds according to the assay being used at each site. Men will continue to be assessed using the overall thresholds throughout. Women with a peak hs-cTn value between the female-specific and the overall thresholds will form our primary cohort. The primary outcome, a 1-year composite of all-cause mortality or readmission for nonfatal myocardial infarction, incident heart failure, or emergent/urgent coronary revascularization, will be compared before and after the implementation of female thresholds using mixed-effects logistic regression models. The cohort and outcomes will be obtained from routinely collected administrative data. The trial is designed to detect a 20% relative risk difference in the primary outcome, or a 2.2% absolute difference, with 82% power. CONCLUSIONS: This pragmatic trial will assess whether adopting lower female hs-cTn thresholds leads to appropriate assessment of women with symptoms suggestive of myocardial infarction, thereby improving treatment and outcomes.

Regulatory-grade clinical trial design using real-world data

Real-world data and evidence provide the potential to address the effectiveness and safety of drugs. The U.S. Food & Drug Administration has initiated a program to evaluate the potential use of real-world evidence for regulatory uses. Whether a study is designed for regulatory purposes or for other purposes, existing regulation and guidance provide a reference for high-quality studies. Clarifying the study objectives and the role of real-world data in the study are important considerations. Robustness and transparency of the analysis allow for greater understanding and acceptance of the study results.

Impact of Multiple Social Determinants of Health on Incident Stroke

BACKGROUND AND PURPOSE

Social determinants of health (SDOH) have been previously associated with incident stroke. Although SDOH often cluster within individuals, few studies have examined associations between incident stroke and multiple SDOH within the same individual. The objective was to determine the individual and cumulative effects of SDOH on incident stroke.

METHODS

This study included 27 813 participants from the REGARDS (Reasons for Geographic and Racial Differences in Stroke) Study, a national, representative, prospective cohort of black and white adults aged ≥45 years. SDOH was the primary exposure. The main outcome was expert adjudicated incident stroke. Cox proportional hazards models examined associations between incident stroke and SDOH, individually and as a count of SDOH, adjusting for potential confounders.

RESULTS

The mean age was 64.7 years (SD 9.4) at baseline; 55.4% were women and 40.4% were blacks. Over a median follow-up of 9.5 years (IQR, 6.0-11.5), we observed 1470 incident stroke events. Of 10 candidate SDOH, 7 were associated with stroke (P<0.10): race, education, income, zip code poverty, health insurance, social isolation, and residence in one of the 10 lowest ranked states for public health infrastructure. A significant age interaction resulted in stratification at 75 years. In fully adjusted models, among individuals <75 years, risk of stroke rose as the number of SDOH increased (hazard ratio for one SDOH, 1.26 [95% CI, 1.02-1.55]; 2 SDOH hazard ratio, 1.38 [95% CI, 1.12-1.71]; and ≥3 SDOH hazard ratio, 1.51 [95% CI, 1.21-1.89]) compared with those without any SDOH. Among those ≥75 years, none of the observed effects reached statistical significance.

CONCLUSIONS

Incremental increases in the number of SDOH were independently associated with higher incident stroke risk in adults aged <75 years, with no statistically significant effects observed in individuals ≥75 years. Targeting individuals with multiple SDOH may help reduce risk of stroke among vulnerable populations.

Validation of Administrative Claims to Ascertain Outcomes in Pivotal Trials of Transcatheter Aortic Valve Replacement

OBJECTIVES

The aim of this study was to evaluate the performance of administrative claims in ascertaining trial clinical events committee-adjudicated outcomes in the U.S. CoreValve studies.

BACKGROUND

Real-world data offer tremendous opportunity to improve outcome ascertainment in clinical trials. However, little is known about the validity of outcomes ascertained using real-world data to capture trial endpoints.

METHODS

Patients enrolled in 3 pivotal trials and 2 pre-market continued-access studies evaluating transcatheter aortic valve replacement were linked to Medicare fee-for-service inpatient claims. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and kappa agreement statistic of claims to detect clinical endpoints and procedural complications in trial patients were calculated.

RESULTS

Claims accurately identified trial-adjudicated deaths (sensitivity, specificity, PPV, and NPV all >99.6%; kappa 1.00). Claims had good performance in identifying trial-adjudicated permanent pacemaker implantation (sensitivity 92.2%, specificity 99.1%, PPV 96.1%, NPV 98.2%, kappa 0.93) and aortic valve reintervention (sensitivity 84.4%, specificity 99.6%, PPV 69.1%, NPV 99.8%, kappa 0.76). Claims had more modest performance in ascertaining trial-adjudicated myocardial infarction (sensitivity 63.6%, specificity 97.2%, PPV 29.9%, NPV 99.3%, kappa 0.39) and acute kidney injury (sensitivity 70.2%, specificity 85.4%, PPV 38.2%, NPV 95.7%, kappa 0.41) and the poorest performance for identifying trial-adjudicated bleeding events (sensitivity 86.4%, specificity 36.8%, PPV 35.0%, NPV 86.3%, kappa 0.16).

CONCLUSIONS

Compared with trial-adjudicated outcomes, claims data performed well in ascertaining death and outcomes with procedural billing codes and more modestly in identifying other outcomes. Claims may be cautiously and selectively used to augment data collection in future cardiovascular device trials.

Use of Administrative Claims to Assess Outcomes and Treatment Effect in Randomized Clinical Trials for Transcatheter Aortic Valve Replacement: Findings From the EXTEND Study

BACKGROUND

Whether passively collected data can substitute for adjudicated outcomes to reproduce the magnitude and direction of treatment effect observed in cardiovascular clinical trials is not well known.

METHODS

We linked adults ≥65 years of age in the HiR (US CoreValve Pivotal High Risk) and SURTAVI trials (Surgical or Transcatheter Aortic Valve Replacement in Intermediate-Risk Patients) to 100% Medicare inpatient claims, January 1, 2011, to December 31, 2016. Primary (eg, death and stroke) and secondary trial end points were compared across treatment arms (eg, transcatheter aortic valve replacement [TAVR] versus surgical aortic valve replacement [SAVR]) using trial-adjudicated outcomes versus outcomes derived from claims at 1 year (HiR) or 2 years (SURTAVI).

RESULTS

Among 600 linked HiR participants (linkage rate, 80.0%), the rate of the trial's primary end point of all-cause mortality occurred in 13.7% of patients receiving TAVR and 16.4% of patients receiving SAVR at 1 year by using both trial data (hazard ratio, 0.84 [95% CI, 0.65-1.09]; P=0.33) and claims data (hazard ratio, 0.86 [95% CI, 0.66-1.11]; P=0.34; interaction P value=0.80). Noninferiority of TAVR relative to SAVR was seen by using both trial- and claims-based outcomes (P_{noninferiority}<0.001 for both). Among 1005 linked SURTAVI trial participants (linkage rate, 60.5%), the trial's primary end point was 12.9% for TAVR and 13.1% for SAVR using trial data (hazard ratio, 1.08 [95% CI, 0.79-1.48]; P=0.90), and 11.3% for TAVR and 12.5% for SAVR patients using claims data (hazard ratio, 1.02 [95% CI, 0.73-1.41]; P=0.58; interaction P value=0.89). TAVR was noninferior to SAVR when compared using both trial and claims (P_{noninferiority}<0.001 for both). Rates of procedural secondary outcomes (eg, aortic valve reintervention, pacemaker rates) were more closely concordant between trial and claims data than nonprocedural outcomes (eg, stroke, bleeding, cardiogenic shock).

CONCLUSIONS

In the HiR and SURTAVI trials, ascertainment of trial primary end points using claims reproduced both the magnitude and direction of treatment effect in comparison with adjudicated event data, but nonfatal and nonprocedural secondary outcomes were not as well reproduced. Use of claims to substitute for adjudicated outcomes in traditional trial treatment comparisons may be valid and feasible for all-cause mortality and certain procedural outcomes but may be less suitable for other end points.

Using Medicare Claims to Identify Acute Clinical Events Following Implantation of Leadless Pacemakers

Background

There is heightened interest in how real-world data (RWD) can be used to supplement or replace traditional mechanisms for collecting clinical information. A critical component in evaluating utility of RWD is assessing the validity and reliability of event measurement. Only two studies have validated Medicare claims with physician-adjudicated data collected in a clinical study and none in the pacemaker patient population. This study compares events identified in physician-adjudicated clinical registry data collected in the Micra Post-Approval Registry (PAR) with events identified via Medicare administrative claims in the Micra Coverage with Evidence (CED) Study.

Methods

Patients who were dually enrolled in the Micra CED and the Micra PAR between March 9, 2017 and December 1, 2017 were included in the validation analysis. All patients intended to be implanted with a Micra device were eligible for participation in the Micra PAR. All Medicare fee-for-service beneficiaries implanted with a Micra device who met the 12-month continuous enrollment criteria were included in the Micra CED. We compared the count of acute (30-day) complications identified in the Medicare claims and the physician-adjudicated PAR data to assess agreement between data sources.

Results

There were 230 patients dually enrolled in the Micra CED and Micra PAR studies during the study period. Overall, there were 17 acute events reported in either the Micra CED or the Micra PAR, with 95% agreement in the identification of events and absence of events between studies. Study disagreement between events reported in either study varied: arteriovenous fistula (50%), pulmonary embolism (67%), hemorrhage/hematoma (75%), and deep vein thrombosis (100%). Among physician-adjudicated events, there was no disagreement between the Micra CED and Micra PAR studies in any event type.

Conclusion

Findings from this study demonstrate high agreement in event identification between Medicare claims data and registries for patients implanted with Micra leadless pacemakers.

Tools and Methods for Real-World Evidence Generation: Pragmatic Trials, Electronic Consent, and Data Linkages

Real-world evidence requires use of new tools and methods to support efficient evidence generation. Among those tools are pragmatic trials, utilization of central/single institutional review board and electronic consent, and data linkages between diverse types of data sources (eg, a trial or registry to administrative claims or electronic medical record data). This article reviews these topics in the context of describing several exemplar use cases specific to rheumatology and provides perspective regarding both the promise and potential pitfalls in using these tools and approaches.

Claims-based cardiovascular outcome identification for clinical research: Results from 7 large randomized cardiovascular clinical trials

BACKGROUND

Medicare insurance claims may provide an efficient means to ascertain follow-up of older participants in clinical research. We sought to determine the accuracy and completeness of claims- versus site-based follow-up with clinical event committee (+CEC) adjudication of cardiovascular outcomes.

METHODS

We performed a retrospective study using linked Medicare and Duke Database of Clinical Trials data. Medicare claims were linked to clinical data from 7 randomized cardiovascular clinical trials. Of 52,476 trial participants, linking resulted in 5,839 (of 10,497 linkage-eligible) Medicare-linked trial participants with fee-for-service A and B coverage. Death, myocardial infarction (MI), stroke, and revascularization incidences were compared using Medicare inpatient claims only, site-reported events (+CEC) only, or a combination of the 2. Randomized treatment effects were compared as a function of whether claims-based, site-based (+CEC), or a combined system was used for event detection.

RESULTS

Among the 5,839 study participants, the annual event rates were similar between claims- and site-based (+CEC) follow-up: death (overall rate 5.2% vs 5.2%; adjusted κ 0.99), MI (2.2% vs 2.3%; adjusted κ 0.96), stroke (0.7% vs 0.7%; adjusted κ 0.99), and any revascularization (7.4% vs 7.9%; adjusted κ 0.95). Of events detected by claims yet not reported by CEC, a minority were reported by sites but negatively adjudicated by CEC (39% of MIs and 18% of strokes). Differences in individual case concordance led to higher event rates when claims- and site-based (+CEC) systems were combined. Randomized treatment effects were similar among the 3 approaches for each outcome of interest.

CONCLUSIONS

Claims- versus site-based (+CEC) follow-up identified similar overall cardiovascular event rates despite meaningful differences in the events detected. Randomized treatment effects were similar using the 2 methods, suggesting claims data could be used to support clinical research leveraging routinely collected data. This approach may lead to more effective evidence generation, synthesis, and appraisal of medical products and inform the strategic approaches toward the National Evaluation System for Health Technology.

Kidney disease trials for the 21st century: innovations in design and conduct

Compared to other specialties, nephrology has reported relatively few clinical trials, and most of these are too small to detect moderate treatment effects. Consequently, interventions that are commonly used by nephrologists have not been adequately tested and some may be ineffective or harmful. More randomized trials are urgently needed to address important clinical questions in patients with kidney disease. The use of robust surrogate markers may accelerate early-phase drug development. However, scientific innovations in trial conduct developed by other specialties should also be adopted to improve trial quality and enable more, larger trials in kidney disease to be completed in the current era of burdensome regulation and escalating research costs. Examples of such innovations include utilizing routinely collected health-care data and disease-specific registries to identify and invite potential trial participants, and for long-term follow-up; use of prescreening to facilitate rapid recruitment of participants; use of pre-randomization run-in periods to improve participant adherence and assess responses to study interventions prior to randomization; and appropriate use of statistics to monitor studies and analyse their results. Nephrology is well positioned to harness such innovations due to its advanced use of electronic health-care records and the development of disease-specific registries. Adopting a population approach and efficient trial conduct along with challenging unscientific regulation may increase the number of definitive clinical trials in nephrology and improve the care of current and future patients.

Determining the Time of Cancer Recurrence Using Claims or Electronic Medical Record Data

PURPOSE

Data from claims and electronic medical records (EMRs) are frequently used to identify clinical events (eg, cancer diagnosis, stroke). However, accurately determining the time of clinical events can be challenging, and the methods used to generate time estimates are underdeveloped. We sought to develop an approach to determine the time of a clinical event-cancer recurrence-using high-dimensional longitudinal structured data.

METHODS

Manual chart abstraction provided information regarding the actual time of cancer recurrence. These data were linked to claims from Medicare or structured EMR data from the Cancer Research Network, which were used to determine time of recurrence for patients with lung or colorectal cancer. We analyzed the longitudinal profile of codes that could help determine the time of recurrence, adjusted for systematic differences between code dates and recurrence dates, and integrated time estimates from different codes to empirically derive an optimal algorithm.

RESULTS

We identified twelve code groups that could help determine the time of recurrence. Using claims data for patients with lung cancer, the optimal algorithm consisted of three code groups and provided an average prediction error of 4.8 months. Using EMR data or applying this approach to patients with colorectal cancer yielded similar results.

CONCLUSION

Time estimates were improved by selecting codes not necessarily the same as those used to identify recurrence, combining time estimates from multiple code groups, and adjusting for systematic bias between code dates and recurrence dates. Improving the accuracy of time estimates for clinical events can facilitate research, quality measurement, and process improvement.

Central Adjudication Identified Additional and Prognostically Important Myocardial Infarctions in Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

In the CHAMPION PHOENIX trial, cangrelor reduced the primary composite end point of death, myocardial infarction (MI), ischemia-driven revascularization, or stent thrombosis at 48 hours. This study aimed to explore the impact of event adjudication and the prognostic importance of MI reported by a clinical events committee (CEC) or site investigators (SIs).

METHODS AND RESULTS

Data from the CHAMPION PHOENIX trial of patients undergoing elective or nonelective percutaneous coronary intervention were analyzed. A CEC systematically identified and adjudicated MI using predefined criteria, a computer algorithm to identify suspected events, and semilogarithmic plots to review biomarker changes. Thirty-day death was modeled using baseline characteristics. Of 10 942 patients, 462 (4.2%) patients had at least 1 MI by 48 hours identified by the CEC (207 [3.8%] cangrelor; 255 [4.7%] clopidogrel; odds ratio [OR] 0.80; 95% CI, 0.67-0.97; P=0.022), and 143 patients had at least 1 MI by 48 hours reported by the SI (60 [1.1%] cangrelor; 83 [1.5%] clopidogrel; OR, 0.72; 95% CI, 0.52-1.01; P=0.053). Of the 462 MIs identified by the CEC, 92 (20%) were reported by SI, and 370 (80%) were not. Of the 143 MI reported by the SI, 51 (36%) were not confirmed by CEC. All categories were associated with an increased adjusted risk for 30-day death (CEC: OR, 5.35; 95% CI, 2.56-11.2; P<0.001; SI: 9.08 [4.01-20.5]; P<0.001; CEC and SI: 10.9 [3.23-36.6]; P<0.001; CEC but not SI: 4.69 [1.94-11.3]; P<0.001; SI but not CEC: 15.4 [5.26-44.9]; P<0.001).

CONCLUSIONS

In patients undergoing percutaneous coronary intervention, CEC procedures identified 3 times as many MIs as the SI reported. Compared with clopidogrel, cangrelor significantly reduced MIs identified by the CEC with a qualitatively similar relative risk reduction in MIs reported by the SI. MIs identified by CEC or reported by SI were independently associated with worse 30-day death. Central adjudication identified additional, prognostically important events.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01156571.

Accuracy of Medical Claims for Identifying Cardiovascular and Bleeding Events After Myocardial Infarction : A Secondary Analysis of the TRANSLATE-ACS Study

Importance

Pragmatic clinical trial designs have proposed the use of medical claims data to ascertain clinical events; however, the accuracy of billed diagnoses in identifying potential events is unclear.

Objectives

To compare the 1-year cumulative incidences of events when events were identified by medical claims vs by physician adjudication and to assess the accuracy of bill-identified events using physician adjudication as the criterion standard.

Design, Setting, and Participants

This post hoc analysis of a clinical trial assessed the medical claims forms and records for all rehospitalizations at 233 US hospitals within 1 year of the index acute myocardial infarction (MI) of 12 365 patients enrolled in the Treatment With Adenosine Diphosphate Receptor Inhibitors: Longitudinal Assessment of Treatment Patterns and Events After Acute Coronary Syndrome (TRANSLATE-ACS) study between April 1, 2010, and October 31, 2012. Fourteen patients (0.1%) died during the index hospitalization and were excluded from analysis. Recurrent MI, stroke, and bleeding events were identified per the International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis and procedural codes in medical bills. These events were independently adjudicated by study physicians through medical record reviews using the prespecified criteria of recurrent MI and stroke and the bleeding definition by the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) scale. Medical claims were reported on a Uniform Bill-04 claims form; claims were collected from all hospitals visited by patients enrolled in TRANSLATE-ACS. Agreement between medical claims-identified events and physician-adjudicated events over the 12 months after discharge was assessed with the κ statistic. Data were analyzed from January 30, 2015, to March 2, 2017.

Main Outcomes and Measures

Event rates within 1 year after MI.

Results

Among 12 365 patients with acute MI, 8890 (71.9%) were men and mean (SD) age was 60 (11.6) years. The cumulative 1-year incidence of events identified by medical claims was 4.3% for MI, 0.9% for stroke, and 5.0% for bleeding. Incidence rates based on physician adjudication were 4.7% for MI, 0.9% for stroke, and 5.4% for bleeding. Agreement between medical claims-identified and physician-adjudicated events was modest, with a κ of 0.76 (95% CI, 0.73 to 0.79) for MI and 0.55 (95% CI, 0.41 to 0.68) for stroke events. In contrast, agreement between medical claims-identified and physician-adjudicated bleeding events was poor, with a κ of 0.24 (95% CI, 0.19 to 0.30) for any hospitalized bleeding event and 0.15 (95% CI, 0.11 to 0.20) for moderate or severe bleeding on the GUSTO scale.

Conclusions and Relevance

Event rates at 1 year after MI were lower for MI, stroke, and bleeding when medical claims were used to identify events than when adjudicated by physicians. Medical claims diagnoses were only modestly accurate in identifying MI and stroke admissions but had limited accuracy for bleeding events. An alternative approach may be needed to ensure good safety surveillance in cardiovascular studies.

Trial Registration

clinicaltrials.gov Identifier: NCT01088503.

Validating the use of registries and claims data to support randomized trials: Rationale and design of the Extending Trial-Based Evaluations of Medical Therapies Using Novel Sources of Data (EXTEND) Study

BACKGROUND

Randomized controlled trials are the "gold standard" for comparing the safety and efficacy of therapies but may be limited due to high costs, lack of feasibility, and difficulty enrolling "real-world" patient populations. The Extending Trial-Based Evaluations of Medical Therapies Using Novel Sources of Data (EXTEND) Study seeks to evaluate whether data collected within procedural registries and claims databases can reproduce trial results by substituting surrogate non-trial-based variables for exposures and outcomes.

METHODS AND RESULTS

Patient-level data from 2 clinical trial programs-the Dual Antiplatelet Therapy Study and the United States CoreValve Studies-will be linked to a combination of national registry, administrative claims, and health system data. The concordance between baseline and outcomes data collected within nontrial data sets and trial information, including adjudicated end point events, will be assessed. We will compare the study results obtained using these alternative data sources to those derived using trial-ascertained variables and end points using trial-adjudicated end points and covariates.

CONCLUSIONS

Linkage of trials to registries and claims data represents an opportunity to use alternative data sources in place of and as adjuncts to randomized clinical trial data but requires further validation. The results of this research will help determine how these data sources can be used to improve our present and future understanding of new medical treatments.

Administrative claims data to support pragmatic clinical trial outcome ascertainment on cardiovascular health

BACKGROUND/AIMS

Health plan administrative claims data present a cost-effective complement to traditional trial-specific ascertainment of clinical events typically conducted through patient report or a single health system electronic health record. We aim to demonstrate the value of health plan claims data in improving the capture of endpoints in longitudinal pragmatic clinical trials.

METHODS

This retrospective cohort study paralleled the design of the ADAPTABLE (Aspirin Dosing: A Patient-centric Trial Assessing Benefits and Long-Term Effectiveness) trial designed to compare the effectiveness of two doses of aspirin. We applied the ADAPTABLE identification query in claims data from Anthem, an American health insurance company, and identified health plan members who met the ADAPTABLE trial criteria. Among the ADAPTABLE eligible members, we selected overlapping members with PCORnet Clinical Data Research Networks in the 2 years prior to the index date (1 April 2014). PCORnet Clinical Data Research Networks consist of network partners (or healthcare systems) that store their electronic health record data in the same format to support multi-institutional research. ADAPTABLE outcome events-cardiovascular hospitalizations including admissions for myocardial infarction, stroke, or cardiac procedures; hospitalizations for major bleeding; and in-hospital deaths-were evaluated for a 2-year follow-up period. Events were classified as within or outside PCORnet Clinical Data Research Networks using facility identifiers affiliated with each hospital stay. Patient characteristics were examined with descriptive statistics, and incidence rates were reported for available Clinical Data Research Networks and claims data.

RESULTS

Among 884,311 ADAPTABLE eligible health plan members, 11,101 patients overlapped with PCORnet Clinical Data Research Networks. Average age was 70 years, 71% were male, and average follow-up was 20.7 months. Patients had 1521 cardiovascular hospitalizations (571 (37.5%) occurred outside PCORnet Clinical Data Research Networks), 710 for major bleeding (296 (41.7%) outside PCORnet Clinical Data Research Networks), and 196 in-hospital deaths (67 (34.2%) outside PCORnet Clinical Data Research Networks). Incidence rates (events per1000 patient-months) differed between available network partners and claims data: cardiovascular hospitalizations, 4.1 (95% confidence interval: 3.9, 4.4) versus 6.6 (95% confidence interval: 6.3, 7.0), major bleeding, 1.8 (95% confidence interval: 1.6, 2.0) versus 3.1 (95% confidence interval: 2.9, 3.3), and in-hospital death, 0.56 (95% confidence interval: 0.47, 0.67) versus 0.85 (95% confidence interval: 0.74, 0.98), respectively.

CONCLUSION

This study demonstrated the value of supplementing longitudinal site-based clinical studies with administrative claims data. Our results suggest that claims data together with network partner electronic health record data constitute an effective vehicle to capture patient outcomes since >30% of patients have non-fatal and fatal events outside of enrolling sites.

Use of Medicare Claims to Identify Adverse Clinical Outcomes After Mitral Valve Repair

BACKGROUND

Clinical event committees are commonly employed for event validation in clinical studies, but little is known about the comparative performance of administrative claims data versus clinician-triggered event adjudication for ascertainment of adverse events in structural heart disease studies.

METHODS AND RESULTS

Medicare claims were linked to 418 patients >65 years of age who underwent transcatheter mitral valve repair (MitraClip) for severe mitral regurgitation from 2007 to 2013 as part of the EVEREST II (Endovascular Valve Edge-to-Edge Repair Study II) High-Risk Registry or the REALISM (Real World Expanded Multicenter Study of the MitraClip System) Continued-Access Registry. Each registry adjudicated mortality, heart failure hospitalization, renal failure, ventilation, and bleeding/transfusion within 1 year. Concordance of claims-based outcomes with events was assessed in 3 ways: 1-year occurrence, cumulative incidence, and synchrony of first events. For event occurrence, positive predictive value (PPV) of claims versus adjudication was the highest for mortality (PPV=97%) and heart failure hospitalization (PPV=69%) but lower for bleeding (PPV=40%) and renal failure (PPV=19%). Whereas claims-based cumulative incidence for mortality, heart failure hospitalization, and renal failure were consistent with clinician-triggered adjudication, incidence curves for bleeding events and ventilation diverged, with claims identifying a greater number of events. When events were detected by both methods, however, over 75% of event dates matched exactly. Mitral valve reinterventions were identified through claims with perfect sensitivity and specificity relative to physician adjudication.

CONCLUSIONS

Ascertainment of mortality, heart failure hospitalization, and renal failure was highly concordant between physician adjudication and administrative claims. Further work is necessary to determine the role of administrative claims in event ascertainment in both prospective and retrospective studies of structural heart disease.

Association of Short Sleep Duration and Atrial Fibrillation

BACKGROUND

Short sleep may be a risk factor for atrial fibrillation. However, previous investigations have been limited by lack of objective sleep measurement and small sample size. We sought to determine the association between objectively measured sleep duration and atrial fibrillation.

METHODS

All 31,079 adult patients undergoing diagnostic polysomnography from 1999 to 2015 at multiple sites within a large hospital network were identified from electronic medical records. Prevalent atrial fibrillation was identified by continuous ECG during polysomnography. Incident atrial fibrillation was identified by diagnostic codes and 12-lead ECGs. Logistic regression and Cox proportional hazards modeling were used to examine the association of sleep duration and atrial fibrillation prevalence and incidence, respectively, adjusting for age, sex, BMI, hypertension, coronary artery disease, cerebrovascular disease, peripheral vascular disease, heart failure, and sleep apnea severity.

RESULTS

We identified 404 cases of prevalent atrial fibrillation among 30,061 individuals (mean age ± SD, 51.0 ± 14.5 years; 51.6% women) undergoing polysomnography. After adjustment, each 1-h reduction in sleep duration was associated with a 1.17-fold (95% CI, 1.11-1.30) increased risk of prevalent atrial fibrillation. Among 27,589 patients without atrial fibrillation at baseline, we identified 1,820 cases of incident atrial fibrillation over 4.6 years median follow-up. After adjustment, each 1-h reduction in sleep duration was associated with a 1.09-fold (95% CI, 1.05-1.13) increased risk for incident atrial fibrillation.

CONCLUSIONS

Short sleep duration is independently associated with prevalent and incident atrial fibrillation. Further research is needed to determine whether interventions to extend sleep can lower atrial fibrillation risk.

Use of Medicare Claims Data for the Identification of Myocardial Infarction: The Reasons for Geographic And Racial Differences in Stroke Study

OBJECTIVES

Assess the validity of Medicare claims for identifying myocardial infarction (MI).

METHODS

We used data from 9951 Medicare beneficiaries 65 years and above in the Reasons for Geographic And Racial Differences in Stroke study. Between 2003 and 2012, 669 participants had an MI identified and adjudicated through study procedures (ie, the gold standard), and 552 had an overnight inpatient claim with a code for MI (ICD-9 code 410.x0 or 410.x1) in any discharge diagnosis position.

RESULTS

Using Medicare claims with a discharge diagnosis code for MI in any position, the positive predictive value (PPV) was 84.3% [95% confidence interval (CI), 80.9%-87.3%] and the sensitivity was 49.0% (95% CI, 44.9%-53.1%). Sensitivity was lower for men (45.8%) versus women (55.1%), microsize MIs (13.7%) versus other MIs (64.7%), type 2 (30.9%), and 4-5 MIs (11.1%) versus type 1 MIs (76.6%), and MIs occurring in-hospital (28.8%) versus out-of-hospital (66.7%). Using Medicare claims with a code for MI in the primary discharge diagnosis position, the PPV was 89.7% (95% CI, 86.3%-92.5%) and sensitivity was 40.1% (95% CI, 36.1%-44.2%). The sensitivity of claims with a code for MI in the primary discharge diagnosis position was lower for microsize versus other MIs, type 2 and 4-5 MIs versus type 1 MIs and MIs occurring in-hospital versus out-of-hospital. Hazard ratios for MI associated with participant characteristics were similar using adjudicated MIs identified through study procedures or claims for MI without further adjudication.

CONCLUSIONS

Medicare claims have a high PPV but low sensitivity for identifying MI and can be used to investigate individual-level characteristics associated with MI.

Working Together to Address Women's Health in Research and Drug Development: Summary of the 2017 Women's Health Congress Preconference Symposium

Historically, women have been underrepresented in clinical research, requiring physicians to extrapolate medical recommendations for women from clinical research done in cohorts consisting predominantly of male participants. While government-funded clinical research has achieved gender parity in phase-3 clinical trials across many biomedical disciplines, improvements are still needed in several facets of women's health research, such as the inclusion of women in early-phase clinical trials, the inclusion of pregnant women and women with physical and intellectual disabilities, the consideration of sex as a biological variable in preclinical research, and the analysis and reporting of sex and gender differences across the full biomedical research continuum. The National Institutes of Health (NIH) Office of Research on Women's Health and the Office of Women's Health of the U.S. Food and Drug Administration (FDA) cosponsored a preconference symposium at the 25th Annual Women's Health Congress, held in Arlington, VA in April, 2017, to highlight gains made and remaining needs regarding the representation of women in clinical research, to introduce innovative procedures and technologies, and to outline revised policy for future studies. Six speakers presented information on a range of subjects related to the representation of women in clinical research and federal initiatives to advance precision medicine. Topics included the following: the return on investment from the NIH-funded Women's Health Initiative; progress in including women in clinical trials for FDA-approved drugs and products; the importance of clinical trials in pregnant women; FDA initiatives to report drug safety during pregnancy; the NIH-funded All of Us Research Program; and efforts to enhance FDA transparency and communications, including the introduction of Drug Trials Snapshots. This article summarizes the major points of the presentations and the discussions that followed.

Evaluation of the Pooled Cohort Risk Equations for Cardiovascular Risk Prediction in a Multiethnic Cohort From the Women's Health Initiative

IMPORTANCE

Atherosclerotic cardiovascular disease (ASCVD) kills approximately 1 in every 3 US women. Current cholesterol, hypertension, and aspirin guidelines recommend calculating 10-year risk of ASCVD using the 2013 Pooled Cohort Equations (PCE). However, numerous studies have reported apparent overestimation of risk with the PCE, and reasons for overestimation are unclear.

OBJECTIVE

We evaluated the predictive accuracy of the PCE in the Women's Health Initiative (WHI), a multiethnic cohort of contemporary US postmenopausal women. We evaluated the effects of time-varying treatments such as aspirin and statins, and ascertainment of additional ASCVD events by linkage with the Centers for Medicare and Medicaid Services (CMS) claims.

DESIGN, SETTING, AND PARTICIPANTS

The WHI recruited the largest number of US women (n = 161 808) with the racial/ethnic, geographic, and age diversity of the general population (1993-1998). For this study, we included women aged 50 to 79 (n = 19 995) participating in the WHI with data on the risk equation variables at baseline and who met the guideline inclusion and exclusion criteria. Median follow-up was 10 years.

MAIN OUTCOMES AND MEASURES

For this study, ASCVD was defined as myocardial infarction, stroke, or cardiovascular death.

RESULTS

Among the 19 995 women (mean [SD] age, 64 [7.3] years; 8305 [41.5%] white, 7688 [38.5%] black, 3491 [17.5%] Hispanic, 103 [0.5%] American Indian, 321 [1.6%] Asian/Pacific Islander, and 87 [0.4%] other/unknown), a total of 1236 ASCVD events occurred in 10 years and were adjudicated through medical record review by WHI investigators. The WHI-adjudicated observed risks were lower than predicted. The observed (predicted) risks for baseline 10-year risk categories less than 5%, 5% to less than 7.5%, 7.5% to less than 10%, and 10% or more were 1.7 (2.8), 4.4 (6.2), 5.3 (8.7), and 12.4 (18.2), respectively. Small changes were noted after adjusting for time-dependent changes in statin and aspirin use. Among women 65 years or older enrolled in Medicare, WHI-adjudicated risks were also lower than predicted, but observed (predicted) risks became aligned after including events ascertained by linkage with CMS for additional surveillance for events: 3.8 (4.3), 7.1 (6.4), 8.3 (8.7), and 18.9 (18.7), respectively. Similar results were seen across ethnic/racial groups. Overall, the equations discriminated risk well (C statistic, 0.726; 95% CI, 0.714-0.738).

CONCLUSIONS AND RELEVANCE

Without including surveillance for ASCVD events using CMS, observed risks in the WHI were lower than predicted by PCE as noted in several other US cohorts, but risks were better aligned after including CMS events.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00000611.

Leveraging electronic health records for clinical research

Electronic health records (EHRs) can be a major tool in the quest to decrease costs and timelines of clinical trial research, generate better evidence for clinical decision making, and advance health care. Over the past decade, EHRs have increasingly offered opportunities to speed up, streamline, and enhance clinical research. EHRs offer a wide range of possible uses in clinical trials, including assisting with prestudy feasibility assessment, patient recruitment, and data capture in care delivery. To fully appreciate these opportunities, health care stakeholders must come together to face critical challenges in leveraging EHR data, including data quality/completeness, information security, stakeholder engagement, and increasing the scale of research infrastructure and related governance. Leaders from academia, government, industry, and professional societies representing patient, provider, researcher, industry, and regulator perspectives convened the Leveraging EHR for Clinical Research Now! Think Tank in Washington, DC (February 18-19, 2016), to identify barriers to using EHRs in clinical research and to generate potential solutions. Think tank members identified a broad range of issues surrounding the use of EHRs in research and proposed a variety of solutions. Recognizing the challenges, the participants identified the urgent need to look more deeply at previous efforts to use these data, share lessons learned, and develop a multidisciplinary agenda for best practices for using EHRs in clinical research. We report the proceedings from this think tank meeting in the following paper.

Network-based approach to prediction and population-based validation of in silico drug repurposing

Here we identify hundreds of new drug-disease associations for over 900 FDA-approved drugs by quantifying the network proximity of disease genes and drug targets in the human (protein–protein) interactome. We select four network-predicted associations to test their causal relationship using large healthcare databases with over 220 million patients and state-of-the-art pharmacoepidemiologic analyses. Using propensity score matching, two of four network-based predictions are validated in patient-level data: carbamazepine is associated with an increased risk of coronary artery disease (CAD) [hazard ratio (HR) 1.56, 95% confidence interval (CI) 1.12–2.18], and hydroxychloroquine is associated with a decreased risk of CAD (HR 0.76, 95% CI 0.59–0.97). In vitro experiments show that hydroxychloroquine attenuates pro-inflammatory cytokine-mediated activation in human aortic endothelial cells, supporting mechanistically its potential beneficial effect in CAD. In summary, we demonstrate that a unique integration of protein-protein interaction network proximity and large-scale patient-level longitudinal data complemented by mechanistic in vitro studies can facilitate drug repurposing.

Repurposing approved drugs could accelerate treatment options for various diseases. Here, the authors use network proximity of disease gene products and drug targets in the human protein interactome to identify drug-disease associations for cardiovascular disease, and validate these using longitudinal healthcare data.

Injection testosterone and adverse cardiovascular events: A case-crossover analysis

CONTEXT

Exogenous testosterone administration may affect blood clotting, polycythaemia, and may increase atherosclerosis, though any association with cardiovascular events is unclear. While the literature is inconclusive, some studies have suggested testosterone use may increase short-term risk of cardiovascular events and stroke, and injection testosterone may convey higher risks than other dosage forms.

OBJECTIVE

We sought to evaluate the short-term cardiovascular risk of receiving injection testosterone.

DESIGN

We conducted a case-crossover analysis comparing injection testosterone exposure in the 7 days prior to an outcome event to referent windows in the past to estimate the acute association of cardiovascular outcomes with the receipt of testosterone injections.

PATIENTS

We identified adult male testosterone users hospitalized with myocardial infarction (MI), stroke or a composite of MI, stroke or unstable angina in US commercial claims (2000-2013) or Medicare (2007-2010) databases.

MEASUREMENTS

We identified testosterone use for the patients from pharmacy dispensing claims or in-office procedure codes in the insurance billing data.

RESULTS

We identified 2898 commercially insured men with events and recent testosterone use, and 339 from Medicare. Injected testosterone was associated with an increased risk of adverse events (composite outcome of myocardial infarction, stroke or unstable angina) in the immediate postinjection period for the older, Medicare population only: commercial insurance, odds ratios (OR) = 0.98 (95% confidence intervals [CI]: 0.86-1.12); Medicare, OR = 1.45 (1.07, 1.98). This association was either greatly attenuated or not present when evaluating receipt of any testosterone dosage forms (injection, gel, patch, implant): commercial insurance, OR = 1.01 (0.92, 1.11); Medicare, OR = 1.26 (95% CI: 0.98-1.63).

CONCLUSIONS

Testosterone injections were uniquely associated with short-term risk of acute cardio- and cerebrovascular events in older adult men following injection receipt.

Impact of hormone therapy on Medicare spending in the Women's Health Initiative randomized clinical trials

BACKGROUND

Randomized trials can compare economic as well as clinical outcomes, but economic data are difficult to collect. Linking clinical trial data with Medicare claims could provide novel information on health care utilization and cost.

METHODS

We linked data from Medicare claims of women ≥65 years old who had Medicare fee-for-service coverage with their clinical data from the Women's Health Initiative trials of conjugated equine estrogens plus medroxyprogesterone acetate (CEE+MPA) versus placebo and of CEE-alone versus placebo. The primary outcome was total Medicare spending during the intervention phase of the trial, and the secondary outcomes were spending on diseases hypothesized a priori to be sensitive to the effects of hormone therapy.

RESULTS

In the CEE+MPA trial, 4,557 participants ≥65 years old were included. Women randomly assigned to CEE+MPA had 4% higher mean Medicare spending overall ($45,690 vs $43,920, P = .08) but 0.5% lower spending for hormone-sensitive diseases ($3,526 vs $3,547, P = .07), with 73% higher spending for coronary heart disease (P = .045) and 122% higher spending for pulmonary embolism (P = .026). In the CEE-alone trial, 3,107 participants were included. Total spending among women randomly assigned to CEE was 3.3% higher ($75,411 vs $72,997, P = .16), and 1.7% higher spending for hormone-sensitive diseases ($5,213 vs $5,127, P = .57), but with 39% lower spending for hip fracture (p<0.03).

CONCLUSIONS

Menopausal hormone therapy increased spending for some diseases, but decreased spending for others. These offsetting effects led to modest (3%-4%), nonsignificant increases in overall spending among women aged 65 years and older.

Advancing a Framework for Regulatory Use of Real-World Evidence: When Real Is Reliable

There is growing interest in regulatory use of randomized pragmatic trials and noninterventional real-world (RW) studies of effectiveness and safety, but there is no agreed-on framework for assessing when this type of evidence is sufficiently reliable. Rather than impose a clinical trial-like paradigm on RW evidence, like blinded treatments or complete, source-verified data, the framework for assessing the utility of RW evidence should be grounded in the context of specific study objectives, clinical events that are likely to be detected in routine care, and the extent to which systematic error (bias) is likely to impact effect estimation. Whether treatment is blinded should depend on how well the outcome can be measured objectively. Qualification of a data source should be based on (1) numbers of patients of interest available for study; (2) if "must-have" data are likely to be recorded, and if so, how and where; (3) the accessibility of systematic follow-up data for the time period of interest; and (4) the potential for systematic errors (bias) in data collection and the likely magnitude of any such bias. Accessible data may not be representative of an entire population, but still may provide reliable evidence about the experience of typical patients treated under conditions of conventional care. Similarly, RW data that falls short of optimal length of follow-up or study size may still be useful in terms of its ability to provide evidence for regulators for subgroups of special interest. Developing a framework to qualify RW evidence in the context of a particular study purpose and data asset will enable broader regulatory use of RW data for approval of new molecular entities and label changes. Reliable information about diverse populations and settings should also help us move closer to more affordable, effective health care.

Chart validation of inpatient ICD-9-CM administrative diagnosis codes for acute myocardial infarction (AMI) among intravenous immune globulin (IGIV) users in the Sentinel Distributed Database

BACKGROUND

The Sentinel Distributed Database (SDD) is a large database of patient-level administrative health care records, primarily derived from insurance claims and electronic health records, and is sponsored by the US Food and Drug Administration for medical product safety evaluations. Acute myocardial infarction (AMI) is a common study endpoint for drug safety studies that rely on health records from the SDD and other administrative databases.

PURPOSE

In this chart validation study, we report on the positive predictive value (PPV) of inpatient International Classification of Diseases, Ninth Revision, Clinical Modification AMI administrative diagnosis codes (410.x1 and 410.x0) in the SDD.

METHODS

As part of an assessment of thromboembolic adverse event risk following treatment with intravenous immune globulin, charts were obtained for 103 potential post-intravenous immune globulin AMI cases. Charts were abstracted by trained nurses and physician-adjudicated based on prespecified diagnostic criteria.

RESULTS

Acute myocardial infarction status could be determined for 89 potential cases. The PPVs for the inpatient AMI diagnoses recorded in the SDD were 75% overall (95% CI, 65-84%), 93% (95% CI, 78-99%) for principal-position diagnoses, 88% (95% CI, 72-97%) for secondary diagnoses, and 38% (95% CI, 20-59%) for position-unspecified diagnoses (eg, diagnoses originating from separate physician claims associated with an inpatient stay). Of the confirmed AMI cases, demand ischemia was the suspected etiology more often for those coded in secondary or unspecified positions (72% and 40%, respectively) than for principal-position AMI diagnoses (21%).

CONCLUSIONS

The PPVs for principal and secondary AMI diagnoses were high and similar to estimates from prior chart validation studies. Position-unspecified diagnosis codes were less likely to represent true AMI cases.

Major Cardiovascular Events in Patients with Gout and Associated Cardiovascular Disease or Heart Failure and Chronic Kidney Disease Initiating a Xanthine Oxidase Inhibitor

BACKGROUND

Several observational studies and meta-analyses have suggested that treating hyperuricemia in patients with gout and moderate or severe chronic kidney disease (CKD) may improve renal and cardiovascular (CV) outcomes.

OBJECTIVE

To evaluate the impact of initiating allopurinol or febuxostat treatment on major CV events in patients with gout, preexisting CV disease (CVD) or heart failure (HF), and stage 3 or 4 CKD in a real-world setting.

METHODS

Patients with gout (aged >18 years) who initiated allopurinol or febuxostat treatment between 2009 and 2013 after a diagnosis of stage 3 or 4 CKD and CVD-including coronary artery disease (CAD), cerebrovascular disease, and peripheral vascular disease (PVD)-or HF were selected from the MarketScan databases. The major CV events included CAD-specific, cerebrovascular disease-specific, and PVD-specific events. Cox proportional hazards modeling identified the predictors of major CV events in aggregate, and of CAD, cerebrovascular disease, and PVD events, individually.

RESULTS

During follow-up, 2426 patients (370 receiving febuxostat and 2056 receiving allopurinol; 63% male; mean age, 73 years) had 162 major CV events (3.8% in those receiving febuxostat vs 7.2% in those receiving allopurinol; P = .015). The rates of major CV events per 1000 person-years were 51.8 (95% confidence interval [CI], 28-87) in patients initiating febuxostat and 99.3 (95% CI, 84-117) among those initiating allopurinol. Overall, 49.4% of patients had a CAD event, 32.5% had a PVD event, and 23.5% had a cerebrovascular disease-specific event. Febuxostat initiation was associated with a significantly lower risk for a major CV event versus patients who initiated allopurinol (hazard ratio, 0.52; P = .02), driven in large part by lower PVD-specific events (P = .026).

CONCLUSION

Patients with moderate-to-severe CKD and CVD or HF who initiated febuxostat treatment had a significantly lower rate of major CV events than patients who initiated allopurinol.

Synergies From Integrating Randomized Controlled Trials and Real-World Data Analyses

Analyses using administrative claims databases or national registries provide estimates of benefits and harms of medications in real-world settings for large and diverse patient populations. Whereas claims-based nonrandomized studies and randomized-controlled trials (RCTs) have distinct limitations, their strengths are complementary. Integrating RCT and claims data offers substantial synergies. We propose obtaining routinely collected longitudinal claims data from RCT participants and discuss the added value of the novel evidence that can be derived from this "information overlap."

Contemporary Time Trends in Use of Antiplatelet Agents Among Patients with Acute Coronary Syndrome and Comorbid Diabetes Mellitus or Chronic Kidney Disease

STUDY OBJECTIVE

To describe contemporary trends of P2Y12 inhibitor use in patients with acute coronary syndrome (ACS) and comorbid diabetes mellitus (DM) and/or chronic kidney disease (CKD) who have a higher risk of recurring ACS and may benefit from treatment with higher efficacy third-generation agents (prasugrel and ticagrelor).

DESIGN

Observational cohort study.

SETTING

A large U.S. commercial insurance program (2009-2015).

PATIENTS

P2Y12 inhibitor initiated within 2 weeks after an ACS event.

MEASUREMENTS AND MAIN RESULTS

We identified 98,649 P2Y12 inhibitor initiators, of whom 24.5% had comorbid DM (no CKD), 10.5% had CKD (no DM), and 12.6% had DM and CKD. Overall, 85.2% of patients initiated clopidogrel, followed by prasugrel (11.6%) and ticagrelor (3.2%). Prasugrel use decreased over time irrespective of preexisting DM and/or CKD; ticagrelor use increased. In logistic regression models accounting for patient demographics and clinical covariates, preexisting DM alone was not associated with prasugrel or ticagrelor versus clopidogrel treatment initiation; however, having CKD with or without DM significantly reduced the likelihood of receiving prasugrel versus clopidogrel (odds ratio [OR] 0.81, 95% confidence interval [CI] 0.74-0.88 for CKD alone; OR 0.91, 95% CI 0.83-0.98 for DM and CKD). Comorbid DM and CKD reduced the odds of initiating ticagrelor versus clopidogrel (OR 0.80, 95% CI 0.70-0.92).

PRINCIPAL CONCLUSIONS

We observed lower or similar use of prasugrel and ticagrelor compared with clopidogrel in patients with ACS and comorbid DM and/or CKD. Given the potential for worse clinical outcomes with clopidogrel in these patients, our findings highlight the need to investigate the implications of these trends on recurrent ACS and bleeding events.

Black-White Differences in Incident Fatal, Nonfatal, and Total Coronary Heart Disease

BACKGROUND

Blacks have higher coronary heart disease (CHD) mortality compared with whites. However, a previous study suggests that nonfatal CHD risk may be lower for black versus white men.

METHODS

We compared fatal and nonfatal CHD incidence and CHD case-fatality among blacks and whites in the Atherosclerosis Risk in Communities study (ARIC), the Cardiovascular Health Study (CHS), and the Reasons for Geographic and Racial Differences in Stroke study (REGARDS) by sex. Participants 45 to 64 years of age in ARIC (men=6479, women=8488) and REGARDS (men=5296, women=7822), and ≥65 years of age in CHS (men=1836, women=2790) and REGARDS (men=3381, women=4112), all without a history of CHD, were analyzed. Fatal and nonfatal CHD incidence was assessed from baseline (ARIC=1987-1989, CHS=1989-1990, REGARDS=2003-2007) through up to 11 years of follow-up.

RESULTS

Age-adjusted hazard ratios comparing black versus white men 45 to 64 years of age in ARIC and REGARDS were 2.09 (95% confidence interval, 1.42-3.06) and 2.11 (1.32-3.38), respectively, for fatal CHD, and 0.82 (0.64-1.05) and 0.94 (0.69-1.28), respectively, for nonfatal CHD. After adjustment for social determinants of health and cardiovascular risk factors, hazard ratios in ARIC and REGARDS were 1.19 (95% confidence interval, 0.74-1.92) and 1.09 (0.62-1.93), respectively, for fatal CHD, and 0.64 (0.47-0.86) and 0.67 (0.48-0.95), respectively, for nonfatal CHD. Similar patterns were present among men ≥65 years of age in CHS and REGARDS. Among women 45 to 64 years of age in ARIC and REGARDS, age-adjusted hazard ratios comparing blacks versus whites were 2.61 (95% confidence interval, 1.57-4.34) and 1.79 (1.06-3.03), respectively, for fatal CHD, and 1.47 (1.13-1.91) and 1.29 (0.91-1.83), respectively, for nonfatal CHD. After multivariable adjustment, hazard ratios in ARIC and REGARDS were 0.67 (95% confidence interval, 0.36-1.24) and 1.00 (0.54-1.85), respectively, for fatal CHD, and 0.70 (0.51-0.97) and 0.70 (0.46-1.06), respectively, for nonfatal CHD. Racial differences in CHD incidence were attenuated among older women. CHD case fatality was higher among black versus white men and women, and the difference remained similar after multivariable adjustment.

CONCLUSIONS

After accounting for social determinants of health and risk factors, black men and women have similar risk for fatal CHD compared with white men and women, respectively. However, the risk for nonfatal CHD is consistently lower for black versus white men and women.

Challenges in conducting clinical trials in nephrology: conclusions from a Kidney Disease-Improving Global Outcomes (KDIGO) Controversies Conference

Despite the high costs of treatment of people with kidney disease and associated comorbid conditions, the amount of reliable information available to guide the care of such patients is very limited. Some treatments have been assessed in randomized trials, but most such trials have been too small to detect treatment effects of a magnitude that would be realistic to achieve with a single intervention. Therefore, KDIGO convened an international, multidisciplinary controversies conference titled "Challenges in the Conduct of Clinical Trials in Nephrology" to identify the key barriers to conducting trials in patients with kidney disease. The conference began with plenary talks focusing on the key areas of discussion that included appropriate trial design (covering identification and evaluation of kidney and nonkidney disease outcomes) and sensible trial execution (with particular emphasis on streamlining both design and conduct). Break out group discussions followed in which the key areas of agreement and remaining controversy were identified. Here we summarize the main findings from the conference and set out a range of potential solutions. If followed, these solutions could ensure future trials among people with kidney disease are sufficiently robust to provide reliable answers and are not constrained by inappropriate complexities in design or conduct.

Validity of Cardiovascular Data From Electronic Sources: The Multi-Ethnic Study of Atherosclerosis and HealthLNK

BACKGROUND

Understanding the validity of data from electronic data research networks is critical to national research initiatives and learning healthcare systems for cardiovascular care. Our goal was to evaluate the degree of agreement of electronic data research networks in comparison with data collected by standardized research approaches in a cohort study.

METHODS

We linked individual-level data from MESA (Multi-Ethnic Study of Atherosclerosis), a community-based cohort, with HealthLNK, a 2006 to 2012 database of electronic health records from 6 Chicago health systems. To evaluate the correlation and agreement of blood pressure in HealthLNK in comparison with in-person MESA examinations, and body mass index in HealthLNK in comparison with MESA, we used Pearson correlation coefficients and Bland-Altman plots. Using diagnoses in MESA as the criterion standard, we calculated the performance of HealthLNK for hypertension, obesity, and diabetes mellitus diagnosis by using International Classification of Diseases, Ninth Revision codes and clinical data. We also identified potential myocardial infarctions, strokes, and heart failure events in HealthLNK and compared them with adjudicated events in MESA.

RESULTS

Of the 1164 MESA participants enrolled at the Chicago Field Center, 802 (68.9%) participants had data in HealthLNK. The correlation was low for systolic blood pressure (0.39; P<0.0001). In comparison with MESA, HealthLNK overestimated systolic blood pressure by 6.5 mm Hg (95% confidence interval, 4.2-7.8). There was a high correlation between body mass index in MESA and HealthLNK (0.94; P<0.0001). HealthLNK underestimated body mass index by 0.3 kg/m² (95% confidence interval, -0.4 to -0.1). With the use of International Classification of Diseases, Ninth Revision codes and clinical data, the sensitivity and specificity of HealthLNK queries for hypertension were 82.4% and 59.4%, for obesity were 73.0% and 89.8%, and for diabetes mellitus were 79.8% and 93.3%. In comparison with adjudicated cardiovascular events in MESA, the concordance rates for myocardial infarction, stroke, and heart failure were, respectively, 41.7% (5/12), 61.5% (8/13), and 62.5% (10/16).

CONCLUSIONS

These findings illustrate the limitations and strengths of electronic data repositories in comparison with information collected by traditional standardized epidemiological approaches for the ascertainment of cardiovascular risk factors and events.

Accuracy of the Atherosclerotic Cardiovascular Risk Equation in a Large Contemporary, Multiethnic Population

BACKGROUND

The accuracy of the 2013 American College of Cardiology/American Heart Association (ACC/AHA) Pooled Cohort Risk Equation for atherosclerotic cardiovascular disease (ASCVD) events in contemporary and ethnically diverse populations is not well understood.

OBJECTIVES

The goal of this study was to evaluate the accuracy of the 2013 ACC/AHA Pooled Cohort Risk Equation within a large, multiethnic population in clinical care.

METHODS

The target population for consideration of cholesterol-lowering therapy in a large, integrated health care delivery system population was identified in 2008 and followed up through 2013. The main analyses excluded those with known ASCVD, diabetes mellitus, low-density lipoprotein cholesterol levels <70 or ≥190 mg/dl, prior lipid-lowering therapy use, or incomplete 5-year follow-up. Patient characteristics were obtained from electronic medical records, and ASCVD events were ascertained by using validated algorithms for hospitalization databases and death certificates. We compared predicted versus observed 5-year ASCVD risk, overall and according to sex and race/ethnicity. We additionally examined predicted versus observed risk in patients with diabetes mellitus.

RESULTS

Among 307,591 eligible adults without diabetes between 40 and 75 years of age, 22,283 were black, 52,917 were Asian/Pacific Islander, and 18,745 were Hispanic. We observed 2,061 ASCVD events during 1,515,142 person-years. In each 5-year predicted ASCVD risk category, observed 5-year ASCVD risk was substantially lower: 0.20% for predicted risk <2.50%; 0.65% for predicted risk 2.50% to <3.75%; 0.90% for predicted risk 3.75% to <5.00%; and 1.85% for predicted risk ≥5.00% (C statistic: 0.74). Similar ASCVD risk overestimation and poor calibration with moderate discrimination (C statistic: 0.68 to 0.74) were observed in sex, racial/ethnic, and socioeconomic status subgroups, and in sensitivity analyses among patients receiving statins for primary prevention. Calibration among 4,242 eligible adults with diabetes was improved, but discrimination was worse (C statistic: 0.64).

CONCLUSIONS

In a large, contemporary "real-world" population, the ACC/AHA Pooled Cohort Risk Equation substantially overestimated actual 5-year risk in adults without diabetes, overall and across sociodemographic subgroups.

Efficient design of clinical trials and epidemiological research: is it possible?

Randomized clinical trials and large-scale, cohort studies continue to have a critical role in generating evidence in cardiovascular medicine; however, the increasing concern is that ballooning costs threaten the clinical trial enterprise. In this Perspectives article, we discuss the changing landscape of clinical research, and clinical trials in particular, focusing on reasons for the increasing costs and inefficiencies. These reasons include excessively complex design, overly restrictive inclusion and exclusion criteria, burdensome regulations, excessive source-data verification, and concerns about the effect of clinical research conduct on workflow. Thought leaders have called on the clinical research community to consider alternative, transformative business models, including those models that focus on simplicity and leveraging of digital resources. We present some examples of innovative approaches by which some investigators have successfully conducted large-scale, clinical trials at relatively low cost. These examples include randomized registry trials, cluster-randomized trials, adaptive trials, and trials that are fully embedded within digital clinical care or administrative platforms.