Validation of an algorithm to identify heart failure hospitalisations in patients with diabetes within the veterans health administration

Accuracy of heart failure ascertainment using routinely collected healthcare data: a systematic review and meta-analysis

BACKGROUND

Ascertainment of heart failure (HF) hospitalizations in cardiovascular trials is costly and complex, involving processes that could be streamlined by using routinely collected healthcare data (RCD). The utility of coded RCD for HF outcome ascertainment in randomized trials requires assessment. We systematically reviewed studies assessing RCD-based HF outcome ascertainment against "gold standard" (GS) methods to study the feasibility of using such methods in clinical trials.

METHODS

Studies assessing International Classification of Disease (ICD) coded RCD-based HF outcome ascertainment against GS methods and reporting at least one agreement statistic were identified by searching MEDLINE and Embase from inception to May 2021. Data on study characteristics, details of RCD and GS data sources and definitions, and test statistics were reviewed. Summary sensitivities and specificities for studies ascertaining acute and prevalent HF were estimated using a bivariate random effects meta-analysis. Heterogeneity was evaluated using I2 statistics and hierarchical summary receiver operating characteristic (HSROC) curves.

RESULTS

A total of 58 studies of 48,643 GS-adjudicated HF events were included in this review. Strategies used to improve case identification included the use of broader coding definitions, combining multiple data sources, and using machine learning algorithms to search free text data, but these methods were not always successful and at times reduced specificity in individual studies. Meta-analysis of 17 acute HF studies showed that RCD algorithms have high specificity (96.2%, 95% confidence interval [CI] 91.5-98.3), but lacked sensitivity (63.5%, 95% CI 51.3-74.1) with similar results for 21 prevalent HF studies. There was considerable heterogeneity between studies.

CONCLUSIONS

RCD can correctly identify HF outcomes but may miss approximately one-third of events. Methods used to improve case identification should also focus on minimizing false positives.

Examining the Burden of Potentially Avoidable Heart Failure Hospitalizations

Background

Two-thirds of the 1 million annual US CHF hospitalizations are for diuresis only; some may be avoidable. We describe a population of low-severity short-stay (

Methods

We conducted a retrospective cohort study within the Premier Healthcare Database, 2016-2021. CHF was defined via an administrative code algorithm. High severity (CHF-H) was marked by cardiogenic shock, the need for respiratory or circulatory support, and/or a Charlson comorbidity index >2. We compared baseline characteristics, processes of care, and outcomes in low-severity (CHF-L) to CHF-H.

Results

Among 301,672 short-stay CHF patients, 135,304 (44.8%) were CHF-L. Compared to CHF-H, CHF-L was younger (70.5 ± 14.1 vs 72.1 ± 13.6 years, p < 0.001), more commonly female (48.6% vs 45.8%, p < 0.001), and more likely to receive IV ACE-I/ARB agents (0.5% vs 0.4%, p = 0.003). Most other IV medications were more common in CHF-H, and anticoagulation was the most prevalent non-diuretic IV therapy in both groups (23.8% vs 33.3%, p < 0.001). Hospital mortality (0.2% vs 1.5%, p < 0.001) and CHF-related 30-day readmissions (8.1% vs 10.5%, p < 0.001) were lower in CHF-L than CHF-H.

Conclusion

Among short-stay CHF patients, nearly ½ meet criteria for CHF-L, and are mainly admitted for fluid management. Avoiding these admissions could result in substantial savings.

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Key Words

• congestive heart failure
• costs
• epidemiology
• hospital
• outcomes

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MESH Headings Collapse

Grants

• scPharmaceuticals, Burlington, MA, USA

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Affiliation(s)

Marya D Zilberberg EviMed Research Group, LLC, Goshen, MA, USA
Brian H Nathanson OptiStatim, LLC, Longmeadow, MA, USA
Kate Sulham scPharmaceuticals, Burlington, MA, USA
John F Mohr scPharmaceuticals, Burlington, MA, USA
Matthew Goodwin scPharmaceuticals, Burlington, MA, USA
Andrew F Shorr Washington Hospital Center, Washington, DC, USA

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Primary Occurrence of Cardiovascular Events After Adding Sodium-Glucose Cotransporter-2 Inhibitors or Glucagon-like Peptide-1 Receptor Agonists Compared With Dipeptidyl Peptidase-4 Inhibitors: A Cohort Study in Veterans With Diabetes

BACKGROUND

The effectiveness of glucagon-like peptide-1 receptor agonists (GLP1RA) and sodium-glucose cotransporter-2 inhibitors (SGLT2i) in preventing major adverse cardiac events (MACE) is uncertain for those without preexisting cardiovascular disease.

OBJECTIVE

To test the hypothesis that MACE incidence was lower with the addition of GLP1RA or SGLT2i compared with dipeptidyl peptidase-4 inhibitors (DPP4i) for primary cardiovascular prevention.

DESIGN

Retrospective cohort study of U.S. veterans from 2001 to 2019.

SETTING

Veterans aged 18 years or older receiving care from the Veterans Health Administration, with data linkage to Medicare, Medicaid, and the National Death Index.

PATIENTS

Veterans adding GLP1RA, SGLT2i, or DPP4i onto metformin, sulfonylurea, or insulin treatment alone or in combination. Episodes were stratified by history of cardiovascular disease.

MEASUREMENTS

Study outcomes were MACE (acute myocardial infarction, stroke, or cardiovascular death) and heart failure (HF) hospitalization. Cox models compared the outcome between medication groups using pairwise comparisons in a weighted cohort adjusted for covariates.

RESULTS

The cohort included 28 759 GLP1RA versus 28 628 DPP4i weighted pairs and 21 200 SGLT2i versus 21 170 DPP4i weighted pairs. Median age was 67 years, and diabetes duration was 8.5 years. Glucagon-like peptide-1 receptor agonists were associated with lower MACE and HF versus DPP4i (adjusted hazard ratio [aHR], 0.82 [95% CI, 0.72 to 0.94]), yielding an adjusted risk difference (aRD) of 3.2 events (CI, 1.1 to 5.0) per 1000 person-years. Sodium-glucose cotransporter-2 inhibitors were not associated with MACE and HF (aHR, 0.91 [CI, 0.78 to 1.08]; aRD, 1.28 [-1.12 to 3.32]) compared with DPP4i.

LIMITATION

Residual confounding; use of DPP4i, GLP1RA, and SGLT2i as first-line therapies were not examined.

CONCLUSION

The addition of GLP1RA was associated with primary reductions of MACE and HF hospitalization compared with DPP4i use; SGLT2i addition was not associated with primary MACE prevention.

PRIMARY FUNDING SOURCE

VA Clinical Science Research and Development and supported in part by the Centers for Diabetes Translation Research.

Descriptive Epidemiology and Outcomes of Patients with Short Stay Hospitalizations for the Treatment of Congestive Heart Failure in the US

Background

Congestive heart failure (CHF) hospitalizations cost the US $35 billion annually. Two-thirds of these admissions, generally requiring </=3 days in the hospital, are solely for the purpose of diuresis, and may be avoidable.

Methods

Among patients discharged with CHF as the principal diagnosis (PD), we compared characteristics and outcomes between those with hospital length of stay (LOS) </=3 days (short, SLOS) and >3 days (long, LLOS) in a cross-sectional multicenter analysis within the 2018 National Inpatient Sample. We applied complex survey methods to calculate nationally representative results.

Results

Among 4,979,350 discharges with any CHF code, 1,177,910 (23.7%) had CHF-PD, of whom 511,555 (43.4%) had SLOS. Patients with SLOS were younger (>/=65 years: 68.3% vs 71.9%), less likely covered by Medicare (71.9% vs 75.4%), and had a lower comorbidity burden (Charlson: 3.9 [2.1] vs 4.5 [2.2) than patients with LLOS; they less frequently developed acute kidney injury (0.4% vs 2.9%) or a need for mechanical ventilation (0.7% vs 2.8%). A higher proportion with SLOS than with LLOS underwent no procedures (70.4% vs 48.4%). Mean LOS (2.2 [0.8] vs 7.7 [6.5]), direct hospital costs ($6150 [$4413]) vs $17,127 [$26,936]), and aggregate annual hospital costs $3,131,560,372 vs $11,359,002,072) were all lower with SLOS than LLOS. All comparisons reached alpha = 0.001.

Conclusion

Among patients admitted for CHF, nearly ½ have LOS </=3 days, and almost ¾ of them requires no inpatient procedures. A more aggressive outpatient heart failure management strategy may allow many patients to avoid hospitalizations and their potential complications and costs.

Evaluation of Medicare Claims for the Development of Heart Failure Diagnostics

BACKGROUND

Although claims data provide a large and efficient source of clinical events, validation is needed prior to use in heart failure (HF) diagnostic development.

METHODS AND RESULTS

Data from the Multisensor Chronic Evaluations in Ambulatory Heart Failure Patients (MultiSENSE) study, used to create the HeartLogic HF diagnostic, were linked with fee-for-service (FFS) Medicare claims. Events were matched by patient ID and date, and agreement was calculated between claims primary HF diagnosis codes and study event adjudication. HF events (HFEs) were defined as inpatient visits, or outpatient visits with intravenous decongestive therapy. Diagnostic performance was measured as HFE-detection sensitivity and false-positive rate (FPR). Linkage of 791 MultiSENSE subjects returned 320 FFS patients with an average follow-up duration of 0.94 years. Although study and claims deaths matched exactly (n = 14), matching was imperfect between study hospitalizations and acute inpatient claims events. Of 239 total events, 165 study hospitalizations (69%) matched inpatient claims events, 28 hospitalizations matched outpatient claims events (12%), 14 hospitalizations were study-unique (6%), and 32 inpatient events were claims-unique (13%). Inpatient HF classification had substantial agreement with study adjudication (κ = 0.823). Diagnostic performance was not different between claims and study events (sensitivity = 75.6% vs 77.6% and FPR = 1.539 vs 1.528 alerts/patient-year). HeartLogic-detected events contributed to > 90% of the HFE costs used for evaluation.

CONCLUSIONS

Acceptable event matching, good agreement of claims diagnostic codes with adjudication, and equivalent diagnostic performance support the validity of using claims for HF diagnostic development.

Ascertaining Framingham heart failure phenotype from inpatient electronic health record data using natural language processing: a multicentre Atherosclerosis Risk in Communities (ARIC) validation study

OBJECTIVES

Using free-text clinical notes and reports from hospitalised patients, determine the performance of natural language processing (NLP) ascertainment of Framingham heart failure (HF) criteria and phenotype.

STUDY DESIGN

A retrospective observational study design of patients hospitalised in 2015 from four hospitals participating in the Atherosclerosis Risk in Communities (ARIC) study was used to determine NLP performance in the ascertainment of Framingham HF criteria and phenotype.

SETTING

Four ARIC study hospitals, each representing an ARIC study region in the USA.

PARTICIPANTS

A stratified random sample of hospitalisations identified using a broad range of International Classification of Disease, ninth revision, diagnostic codes indicative of an HF event and occurring during 2015 was drawn for this study. A randomly selected set of 394 hospitalisations was used as the derivation dataset and 406 hospitalisations was used as the validation dataset.

INTERVENTION

Use of NLP on free-text clinical notes and reports to ascertain Framingham HF criteria and phenotype.

PRIMARY AND SECONDARY OUTCOME MEASURES

NLP performance as measured by sensitivity, specificity, positive-predictive value (PPV) and agreement in ascertainment of Framingham HF criteria and phenotype. Manual medical record review by trained ARIC abstractors was used as the reference standard.

RESULTS

Overall, performance of NLP ascertainment of Framingham HF phenotype in the validation dataset was good, with 78.8%, 81.7%, 84.4% and 80.0% for sensitivity, specificity, PPV and agreement, respectively.

CONCLUSIONS

By decreasing the need for manual chart review, our results on the use of NLP to ascertain Framingham HF phenotype from free-text electronic health record data suggest that validated NLP technology holds the potential for significantly improving the feasibility and efficiency of conducting large-scale epidemiologic surveillance of HF prevalence and incidence.

Hospitalization for Heart Failure Among Patients With Diabetes Mellitus and Reduced Kidney Function Treated With Metformin Versus Sulfonylureas: A Retrospective Cohort Study

Background Metformin and sulfonylurea are commonly prescribed oral medications for type 2 diabetes mellitus. The association of metformin and sulfonylureas on heart failure outcomes in patients with reduced estimated glomerular filtration rate remains poorly understood. Methods and Results This retrospective cohort combined data from National Veterans Health Administration, Medicare, Medicaid, and the National Death Index. New users of metformin or sulfonylurea who reached an estimated glomerular filtration rate of 60 mL/min per 1.73 m2 or serum creatinine of 1.5 mg/dL and continued metformin or sulfonylurea were included. The primary outcome was hospitalization for heart failure. Echocardiogram reports were obtained to determine each patient's ejection fraction (EF) (reduced EF <40%; midrange EF 40%-49%; ≥50%). The primary analysis estimated the cause-specific hazard ratios for metformin versus sulfonylurea and estimated the cumulative incidence functions for heart failure hospitalization and competing events. The weighted cohort included 24 685 metformin users and 24 805 sulfonylurea users with reduced kidney function (median age 70 years, estimated glomerular filtration rate 55.8 mL/min per 1.73 m2). The prevalence of underlying heart failure (12.1%) and cardiovascular disease (31.7%) was similar between groups. There were 16.9 (95% CI, 15.8-18.1) versus 20.7 (95% CI, 19.5-22.0) heart failure hospitalizations per 1000 person-years for metformin and sulfonylurea users, respectively, yielding a cause-specific hazard of 0.85 (95% CI, 0.78-0.93). Among heart failure hospitalizations, 44.5% did not have echocardiogram information available; 29.3% were categorized as reduced EF, 8.9% as midrange EF, and 17.2% as preserved EF. Heart failure hospitalization with reduced EF (hazard ratio, 0.79; 95% CI, 0.67-0.93) and unknown EF (hazard ratio, 0.84; 95% CI 0.74-96) were significantly lower in metformin versus sulfonylurea users. Conclusions Among patients with type 2 diabetes mellitus who developed worsening kidney function, persistent metformin compared with sulfonylurea use was associated with reduced heart failure hospitalization.

Accuracy of Japanese claims data in identifying diabetes-related complications

PURPOSE

To evaluate the accuracy of various claims-based definitions of diabetes-related complications (coronary artery disease [CAD], heart failure, cerebrovascular disease and dialysis).

METHODS

We evaluated data on 1379 inpatients who received care at the Niigata University Medical & Dental Hospital in September 2018. Manual electronic medical chart reviews were conducted for all patients with regard to diabetes-related complications and were used as the gold standard. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of each claims-based definition associated with diabetes-related complications based on Diagnosis Procedure Combination (DPC), International Classification of Diseases, Tenth Revision (ICD-10) codes, procedure codes and medication codes were calculated.

RESULTS

DPC-based definitions had higher sensitivity, specificity, and PPV than ICD-10 code definitions for CAD and cerebrovascular disease, with sensitivity of 0.963-1.000 and 0.905-0.952, specificity of 1.000 and 1.000, and PPV of 1.000 and 1.000, respectively. Sensitivity, specificity, and PPV were high using procedure codes for CAD and dialysis, with sensitivity of 0.963 and 1.000, specificity of 1.000 and 1.000, and PPV of 1.000 and 1.000, respectively. DPC and/or ICD-10 codes + medication were better for heart failure than the ICD-10 code definition, with sensitivity of 0.933, specificity of 1.000, and PPV of 1.000. The PPVs were lower than 60% for all diabetes-related complications using ICD-10 codes only.

CONCLUSION

The DPC-based definitions for CAD and cerebrovascular disease, procedure codes for CAD and dialysis, and DPC or ICD-10 codes with medication codes for heart failure could accurately identify these diabetes-related complications from claims databases.

Comprehensive review of ICD-9 code accuracies to measure multimorbidity in administrative data

Background

Quantifying the burden of multimorbidity for healthcare research using administrative data has been constrained. Existing measures incompletely capture chronic conditions of relevance and are narrowly focused on risk-adjustment for mortality, healthcare cost or utilization. Moreover, the measures have not undergone a rigorous review for how accurately the components, specifically the International Classification of Diseases, Ninth Revision (ICD-9) codes, represent the chronic conditions that comprise the measures. We performed a comprehensive, structured literature review of research studies on the accuracy of ICD-9 codes validated using external sources across an inventory of 81 chronic conditions. The conditions as a weighted measure set have previously been demonstrated to impact not only mortality but also physical and mental health-related quality of life.

Methods

For each of 81 conditions we performed a structured literature search with the goal to identify 1) studies that externally validate ICD-9 codes mapped to each chronic condition against an external source of data, and 2) the accuracy of ICD-9 codes reported in the identified validation studies. The primary measure of accuracy was the positive predictive value (PPV). We also reported negative predictive value (NPV), sensitivity, specificity, and kappa statistics when available. We searched PubMed and Google Scholar for studies published before June 2019.

Results

We identified studies with validation statistics of ICD-9 codes for 51 (64%) of 81 conditions. Most of the studies (47/51 or 92%) used medical chart review as the external reference standard. Of the validated using medical chart review, the median (range) of mean PPVs was 85% (39–100%) and NPVs was 91% (41–100%). Most conditions had at least one validation study reporting PPV ≥70%.

Conclusions

To help facilitate the use of patient-centered measures of multimorbidity in administrative data, this review provides the accuracy of ICD-9 codes for chronic conditions that impact a universally valued patient-centered outcome: health-related quality of life. These findings will assist health services studies that measure chronic disease burden and risk-adjust for comorbidity and multimorbidity using patient-centered outcomes in administrative data.

Incidence of statin use in older adults with and without cardiovascular disease and diabetes mellitus, January 2008- March 2018

Background

Data from randomized controlled trials and observational studies on older adults who take statins for primary prevention of atherosclerotic cardiovascular disease are limited. To determine the incidence of statin use in older adults with and without cardiovascular disease (CVD) and/or diabetes (DM), we conducted a descriptive observational study.

Methods

The cohort consisted of health plan members in the NIH Collaboratory Distributed Research Network aged >75 years who had continuous drug and medical benefits for ≥183 days during the study period, January 1, 2008- March 31, 2018. We defined DM and CVD using diagnosis codes, and identified statins using dispensing data. Statin use was considered incident if a member had no evidence of statin exposure in the claims during the previous 183 days, and the use was considered long-term if statins were supplied for ≥180 days. Incidence rates were reported among members with and without CVD and/or diabetes, and stratified by year, sex, and age group.

Results

Among 757,569 eligible members, 109,306 older adults initiated statins and 54,624 became long-term users. Health plan members with CVD had the highest incidence of statin use (143.9 initiators per 1,000 member-years for CVD & DM; 114.5 initiators per 1,000 member-years for CVD & No DM). Among health plan members without CVD, those with DM had rates of statin use that were over two times higher than members without DM (76.1 versus 34.5 initiators per 1,000 member-years, respectively). Statin initiation remained steady throughout 2008–2016, was slightly higher in males, and declined with increasing age.

Conclusion

Incidence of statin use varied by CVD and DM comorbidity, and was lowest among those without CVD. These results highlight the potential clinical equipoise to conduct large pragmatic clinical trials to generate evidence that could be used to inform future blood cholesterol guidelines.

Evaluation of Frailty as an Unmeasured Confounder in Observational Studies of Antidiabetic Medications

BACKGROUND

It is unknown whether observational studies evaluating the association between antidiabetic medications and mortality adequately account for frailty. Our objectives were to evaluate if frailty was a potential confounder in the relationship between antidiabetic medication regimen and mortality and how well administrative and clinical electronic health record (EHR) data account for frailty.

METHODS

We conducted a retrospective cohort study in a single Veterans Health Administration (VHA) healthcare system of 500 hospitalizations-the majority due to heart failure-of Veterans who received regular VHA care and initiated type 2 diabetes treatment from 2001 to 2008. We measured frailty using a modified frailty index (FI, >0.21 frail). We obtained antidiabetic medication regimen and time-to-death from administrative sources. We compared FI among patients on different antidiabetic regimens. Stepwise Cox proportional hazards regression estimated time-to-death by demographic, administrative, clinical EHR, and FI data.

RESULTS

Median FI was 0.22 (interquartile range 0.18, 0.27). Frailty differed across antidiabetic regimens (p < .001). An FI increase of 0.05 was associated with an increased risk of death (hazard ratio 1.45, 95% confidence interval 1.32, 1.60). Cox proportional hazards model for time-to-death including demographic, administrative, and clinical EHR data had a c-statistic of 0.70; adding FI showed marginal improvement (c-statistic 0.72).

CONCLUSIONS

Frailty was associated with antidiabetic regimen and death, and may confound that relationship. Demographic, administrative, and clinical EHR data, commonly used to balance differences among exposure groups, performed moderately well in assessing risk of death, with minimal gain from adding frailty. Study design and analytic techniques can help minimize potential confounding by frailty in observational studies.

Type 2 diabetes increases the risk of hospital admission for heart failure and reduces the risk of in hospital mortality in Spain (2001-2015)

BACKGROUND

To compare trends in incidence, clinical characteristics and outcomes of heart failure (HF) hospitalizations among patients with or without type 2 diabetes (T2DM) in Spain (2001-2015).

METHODS

We used national hospital discharge data to select hospital admissions for HF as primary diagnosis. Incidence, comorbidities, diagnostic and therapeutic procedures, and in hospital mortality (IHM) were analyzed.

RESULTS

We identified a total of 1,501,811 admissions for HF (36.87% with T2DM). Incidences were higher among those with T2DM than those without diabetes. The adjusted incidence of HF among T2DM patients was 4.93 higher than for non-diabetic subjects (IRR 4.93;95%CI 4.91-4.95). Jointpoint analysis showed that sex-age-adjusted admissions in T2DM patients with HF increased by 7.12% per year from 2001 to 2007 and stabilized afterwards. For non-diabetic patients a constant increase overtime of around 1% was found. Patients with T2DM were significantly younger than patients without diabetes (77.22 vs. 79.36 years) and had more coexisting medical conditions according to the Charlson Comorbidity Index (mean CCI 1.99 ± 0.88 vs. 1.90 ± 0.86). For the total time period, crude IHM was lower for T2DM patients than for non-diabetic people (8.35% vs, 10.57%; p < 0.05) and the association remained significant after multivariable adjustment ((OR, 0.84; 95%CI 0.83-0.86).). Female sex, older age and multiple comorbidities were significant risk factors for IHM.

CONCLUSIONS

T2DM increases the risk of admission for HF by five-fold. Our study demonstrates an increase in hospitalization for HF in diabetic patients from 2001 to 2007 and stabilization afterwards. T2DM was associated with a lower IHM after hospitalization for HF.