Chart validation of inpatient International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) administrative diagnosis codes for venous thromboembolism (VTE) among intravenous immune globulin (IGIV) users in the Sentinel Distributed Database

Long-term incidence, risk factors and complications for venous thromboembolism in patients with systemic lupus erythematosus

AIM

To compare frequency, incidence rates (IR), risk factors and outcomes of a first venous thromboembolic event (VTE) between patients with systemic lupus erythematosus (SLE) and controls.

METHODS

Using state-wide longitudinal hospital data from Western Australia (WA), we recorded venous thrombosis (VT) and pulmonary embolism (PE) in patients with SLE (n = 1854, median age 40, 86% female) and matched hospitalised controls (n = 12,107, median age 40 years, females 88.6%) in the period 1985-2015. Results presented are medians, frequency, IR per 1000 person years (PY) and odds, rate, or adjusted hazard ratios (OR/RR/a-HR) with 95% confidence intervals (CI).

RESULTS

Patients with SLE had significantly higher odds (12.8 vs 3.3%; OR 4.26, CI 3.60-5.05) and IR for a first VTE (10.09 vs 1.52; RR 6.64; CI 5.56-7.79). Over the three study decades, the IR for PE declined in patients with SLE from 7.74 to 3.75/1000 PY (p < .01) with no changes observed for VT or in controls. VTE recurred more frequently in patients with SLE (24.1% vs 10.2 %) (p < .01). Antiphospholipid antibodies (aPL) (a-HR 4.24, CI 2.50-7.19), serositis (a-HR 2.70, CI 1.86-3.91), lupus nephritis (a-HR 1.75 CI 1.25-2.33) and thrombocytopenia (a-HR 1.65 (1.10-2.49) were the strongest disease risk factors for VTE only in patients with SLE, while arterial hypertension, smoking and obesity were independent VTE risk factors for both groups. VTE was not associated with an increased risk for arterial events, but PE increased the risk for pulmonary hypertension (PH) in both patients with SLE (a-HR 6.47, CI 3.73-11.23) and controls (a-HR 9.09, CI 3.50-23.63). VTE increased the risk of death in both patients with SLE (a-HR 2.02, CI 1.50-2.70) and controls (a-HR 6.63, CI 5.21-8.42) after 10 years of follow-up.

CONCLUSIONS

VTE affected 12.8% of patients with SLE at six times the VTE rate in controls with aPL as the strongest, but not the only risk factor in SLE. The risk of PH was increased in both groups following PE, but VTE did not associate with an increased risk of arterial events.

Risk of Arterial and Venous Thrombotic Events Among Patients with COVID-19: A Multi-National Collaboration of Regulatory Agencies from Canada, Europe, and United States

Purpose

Few studies have examined how the absolute risk of thromboembolism with COVID-19 has evolved over time across different countries. Researchers from the European Medicines Agency, Health Canada, and the United States (US) Food and Drug Administration established a collaboration to evaluate the absolute risk of arterial (ATE) and venous thromboembolism (VTE) in the 90 days after diagnosis of COVID-19 in the ambulatory (eg, outpatient, emergency department, nursing facility) setting from seven countries across North America (Canada, US) and Europe (England, Germany, Italy, Netherlands, and Spain) within periods before and during COVID-19 vaccine availability.

Patients and Methods

We conducted cohort studies of patients initially diagnosed with COVID-19 in the ambulatory setting from the seven specified countries. Patients were followed for 90 days after COVID-19 diagnosis. The primary outcomes were ATE and VTE over 90 days from diagnosis date. We measured country-level estimates of 90-day absolute risk (with 95% confidence intervals) of ATE and VTE.

Results

The seven cohorts included 1,061,565 patients initially diagnosed with COVID-19 in the ambulatory setting before COVID-19 vaccines were available (through November 2020). The 90-day absolute risk of ATE during this period ranged from 0.11% (0.09-0.13%) in Canada to 1.01% (0.97-1.05%) in the US, and the 90-day absolute risk of VTE ranged from 0.23% (0.21-0.26%) in Canada to 0.84% (0.80-0.89%) in England. The seven cohorts included 3,544,062 patients with COVID-19 during vaccine availability (beginning December 2020). The 90-day absolute risk of ATE during this period ranged from 0.06% (0.06-0.07%) in England to 1.04% (1.01-1.06%) in the US, and the 90-day absolute risk of VTE ranged from 0.25% (0.24-0.26%) in England to 1.02% (0.99-1.04%) in the US.

Conclusion

There was heterogeneity by country in 90-day absolute risk of ATE and VTE after ambulatory COVID-19 diagnosis both before and during COVID-19 vaccine availability.

Validity of Routine Health Data To Identify Safety Outcomes of Interest For Covid-19 Vaccines and Therapeutics in the Context of the Emerging Pandemic: A Comprehensive Literature Review

Introduction

Regulatory guidance encourages transparent reporting of information on the quality and validity of electronic health record data being used to generate real-world benefit-risk evidence for vaccines and therapeutics. We aimed to provide an overview of the availability of validated diagnostic algorithms for selected safety endpoints for Coronavirus disease 2019 (COVID-19) vaccines and therapeutics in the context of the emerging pandemic prior to December 2020.

Methods

We reviewed the literature up to December 2020 to identify validation studies for various safety events of interest, including myocardial infarction, arrhythmia, myocarditis, acute cardiac injury, vasculitis/vasculopathy, venous thromboembolism, stroke, respiratory distress syndrome (RDS), pneumonitis, cytokine release syndrome (CRS), multiple organ dysfunction syndrome, and renal failure. We included studies published between 2015 and 2020 that were considered high quality assessed with QUADAS and that reported positive predictive values (PPVs).

Results

Out of 43 identified studies, we found that diagnostic algorithms for cardiovascular outcomes were supported by the highest number of validation studies (n=17). Accurate algorithms are available for myocardial infarction (median PPV 80%; IQR 22%), arrhythmia (PPV range >70%), venous thromboembolism (median PPV: 73%) and ischaemic stroke (PPV range ≥85%). We found a lack of validation studies for less common respiratory and cardiac safety outcomes of interest (eg, pneumonitis and myocarditis), as well as for COVID-specific complications (CRS, RDS).

Conclusion

There is a need for better understanding of barriers to conducting validation studies, including data governance restrictions. Regulatory guidance should promote embedding validation within real-world EHR research used for decision-making.

Concepts of Designing and Implementing Pharmacoepidemiology Studies on the Safety of Systemic Treatments in Dermatology Practice

The U.S. Food and Drug Administration and clinical guidelines use evidence from pharmacoepidemiology studies to inform prescribing decisions and fill evidence gaps left by randomized controlled trials (RCTs). The long-term safety and infrequent adverse reactions are not well-understood when RCTs are short and involve few patients, as is the case for most systemic immunomodulating drugs in dermatology. A better understanding of the design and implementation of pharmacoepidemiology studies will help practitioners assess the accuracy of etiologic findings and use them with confidence in clinical practice. Conducting pharmacoepidemiology studies follows a structured approach, which we discuss in this article: (i) a design layer connects the research question with the appropriate study design, and considering which hypothetical RCT one ideally would want to conduct reduces inadvertent investigator errors; (ii) a measurement layer transforms longitudinal patient-level data into variables that identify the study population, patient characteristics, treatment, and outcomes; and (iii) the analysis focuses on the causal treatment effect estimation. The review and interpretation of pharmacoepidemiology studies should consider issues beyond a typical review of RCTs, chiefly the lack of baseline randomization and the use of secondary data. Well-designed and well-conducted pharmacoepidemiologic studies complement dermatology practice with critical information on prescribing systemic medications.

The prevalence of thrombocytopenia in patients with acute cancer-associated thrombosis

Venous thromboembolism (VTE) and thrombocytopenia are frequently encountered complications in patients with cancer. Although there are several studies evaluating the safety and efficacy of anticoagulation regimens in patients with cancer-associated thrombosis (CAT) with thrombocytopenia, there is a paucity of data assessing the scope of the concurrent diagnoses. This study evaluates the prevalence of thrombocytopenia among patients with acute CAT. A retrospective cohort analysis of adult patients with cancer was conducted at Beth Israel Deaconess Medical Center between 2010 and 2021 with CAT (acute VTE within 6 months after new diagnosis of malignancy). VTE included acute deep vein thrombosis, pulmonary embolism, abdominal or intrathoracic venous thrombosis, and cerebral sinus thrombosis. The lowest platelet count within 2 weeks of (before or after) the index VTE event was identified to assess the frequency and grade of concurrent thrombocytopenia. We identified 3635 patients with CAT (80% solid tumors, 18% hematologic malignancies, and 2% multiple concurrent cancer diagnoses). Thrombocytopenia (defined as platelet count <100 000/μL) occurred in 22% (95% CI 21%-24%) of patients with CAT with solid tumors diagnoses and 47% (95% CI 43%-51%) of patients with CAT and hematologic malignancies. Severe thrombocytopenia (platelet count <50 000/μL) occurred in 7% (95% CI 6%-8%) of patients with solid tumors and 30% (95% CI 27%-34%) of patients with hematologic malignancies. Concurrent diagnoses of CAT and thrombocytopenia are very common, especially among patients with hematologic malignancies.

Venous Thromboembolism in Patients With Bullous Pemphigoid

Importance

Studies have linked bullous pemphigoid (BP) with venous thromboembolism (VTE) across several data sources finding 6-fold to 15-fold increased incidence rates.

Objective

To determine the incidence of VTE in patients with BP compared with similar controls.

Design, Setting, and Participants

This cohort study used insurance claims data from a nationwide US health care database from January 1, 2004, through January 1, 2020. Patients with dermatologist-recorded BP were identified (≥2 diagnoses of BP [International Classification of Diseases, Ninth Revision (ICD-9) 694.5 and ICD-10 L12.0] recorded by dermatologists within 1 year). Risk-set sampling identified comparator patients without BP and free of other chronic inflammatory skin diseases. Patients were followed-up until the first of the following events occurred: VTE, death, disenrollment, or end of data stream.

Exposures

Patients with BP compared with those without BP and free of other chronic inflammatory skin diseases (CISD).

Main outcome

Venous thromboembolism events were identified and incidence rates were computed before and after propensity-score (PS) matching to account for VTE risk factors. Hazard ratios (HRs) compared the incidence of VTE in BP vs non-CISD.

Results

Overall, 2654 patients with BP and 26 814 comparator patients without BP or another CISD were identified. The mean (SD) age in the BP group was 73.0 (12.6) years and 55.0 (18.9) years in the non-CSID group. With a median follow-up time was 2 years, the unadjusted incidence rate (per 1000 person-years) of outpatient or inpatient VTE was 8.5 in the BP group compared with 1.8 in patients without a CISD. Adjusted rates were 6.7 in the BP group compared with 3.0 in the non-CISD group. Age-specific adjusted incidence rates (per 1000 person-years) in patients aged 50 to 74 years was 6.0 (vs 2.9 in the non-CISD group) and in those aged 75 years or older was 7.1 (vs 4.53 in the non-CISD group). After 1:1 propensity-score matching including 60 VTE risk factors and severity markers, BP was associated with a 2-fold increased risk of VTE (2.24 [1.26-3.98]) vs those in the non-CISD group. When restricting to patients aged 50 years or older, the adjusted relative risk of VTE was 1.82 (1.05-3.16) for the BP vs non-CISD groups.

Conclusions

In this nationwide US cohort study, BP was associated with a 2-fold increased incidence of VTE after controlling for VTE risk factors in a dermatology patient population.

Risk of admission to hospital with arterial or venous thromboembolism among patients diagnosed in the ambulatory setting with covid-19 compared with influenza: retrospective cohort study

Objective

To measure the 90 day risk of arterial thromboembolism and venous thromboembolism among patients diagnosed with covid-19 in the ambulatory (ie, outpatient, emergency department, or institutional) setting during periods before and during covid-19 vaccine availability and compare results to patients with ambulatory diagnosed influenza.

Design

Retrospective cohort study.

Setting

Four integrated health systems and two national health insurers in the US Food and Drug Administration's Sentinel System.

Participants

Patients with ambulatory diagnosed covid-19 when vaccines were unavailable in the US (period 1, 1 April-30 November 2020; n=272 065) and when vaccines were available in the US (period 2, 1 December 2020-31 May 2021; n=342 103), and patients with ambulatory diagnosed influenza (1 October 2018-30 April 2019; n=118 618).

Main outcome measures

Arterial thromboembolism (hospital diagnosis of acute myocardial infarction or ischemic stroke) and venous thromboembolism (hospital diagnosis of acute deep venous thrombosis or pulmonary embolism) within 90 days after ambulatory covid-19 or influenza diagnosis. We developed propensity scores to account for differences between the cohorts and used weighted Cox regression to estimate adjusted hazard ratios of outcomes with 95% confidence intervals for covid-19 during periods 1 and 2 versus influenza.

Results

90 day absolute risk of arterial thromboembolism with covid-19 was 1.01% (95% confidence interval 0.97% to 1.05%) during period 1, 1.06% (1.03% to 1.10%) during period 2, and with influenza was 0.45% (0.41% to 0.49%). The risk of arterial thromboembolism was higher for patients with covid-19 during period 1 (adjusted hazard ratio 1.53 (95% confidence interval 1.38 to 1.69)) and period 2 (1.69 (1.53 to 1.86)) than for patients with influenza. 90 day absolute risk of venous thromboembolism with covid-19 was 0.73% (0.70% to 0.77%) during period 1, 0.88% (0.84 to 0.91%) during period 2, and with influenza was 0.18% (0.16% to 0.21%). Risk of venous thromboembolism was higher with covid-19 during period 1 (adjusted hazard ratio 2.86 (2.46 to 3.32)) and period 2 (3.56 (3.08 to 4.12)) than with influenza.

Conclusions

Patients diagnosed with covid-19 in the ambulatory setting had a higher 90 day risk of admission to hospital with arterial thromboembolism and venous thromboembolism both before and after covid-19 vaccine availability compared with patients with influenza.

Use of Structured Electronic Health Records Data Elements for the Development of Computable Phenotypes to Identify Potential Adverse Events Associated with Intravenous Immunoglobulin Infusion

INTRODUCTION

Detection of adverse reactions to drugs and biologic agents is an important component of regulatory approval and post-market safety evaluation. Real-world data, including insurance claims and electronic health records data, are increasingly used for the evaluation of potential safety outcomes; however, there are different types of data elements available within these data resources, impacting the development and performance of computable phenotypes for the identification of adverse events (AEs) associated with a given therapy.

OBJECTIVE

To evaluate the utility of different types of data elements to the performance of computable phenotypes for AEs.

METHODS

We used intravenous immunoglobulin (IVIG) as a model therapeutic agent and conducted a single-center, retrospective study of 3897 individuals who had at least one IVIG administration between 1 January 2014 and 31 December 2019. We identified the potential occurrence of four different AEs, including two proximal AEs (anaphylaxis and heart rate alterations) and two distal AEs (thrombosis and hemolysis). We considered three different computable phenotypes: (1) an International Classification of Disease (ICD)-based phenotype; (2) a phenotype-based on EHR-derived contextual information based on structured data elements, including laboratory values, medication administrations, or vital signs; and (3) a compound phenotype that required both an ICD code for the AE in combination with additional EHR-derived structured data elements. We evaluated the performance of each of these computable phenotypes compared with chart review-based identification of AEs, assessing the positive predictive value (PPV), specificity, and estimated sensitivity of each computable phenotype method.

RESULTS

Compound computable phenotypes had a high positive predictive value for acute AEs such as anaphylaxis and bradycardia or tachycardia; however, few patients had both ICD codes and the relevant contextual data, which decreased the sensitivity of these computable phenotypes. In contrast, computable phenotypes for distal AEs (i.e., thrombotic events or hemolysis) frequently had ICD codes for these conditions in the absence of an AE due to a prior history of such events, suggesting that patient medical history of AEs negatively impacted the PPV of computable phenotypes based on ICD codes.

CONCLUSIONS

These data provide evidence for the utility of different structured data elements in computable phenotypes for AEs. Such computable phenotypes can be used across different data sources for the detection of infusion-related adverse events.

Association of COVID-19 vs Influenza With Risk of Arterial and Venous Thrombotic Events Among Hospitalized Patients

IMPORTANCE

The incidence of arterial thromboembolism and venous thromboembolism in persons with COVID-19 remains unclear.

OBJECTIVE

To measure the 90-day risk of arterial thromboembolism and venous thromboembolism in patients hospitalized with COVID-19 before or during COVID-19 vaccine availability vs patients hospitalized with influenza.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of 41 443 patients hospitalized with COVID-19 before vaccine availability (April-November 2020), 44 194 patients hospitalized with COVID-19 during vaccine availability (December 2020-May 2021), and 8269 patients hospitalized with influenza (October 2018-April 2019) in the US Food and Drug Administration Sentinel System (data from 2 national health insurers and 4 regional integrated health systems).

EXPOSURES

COVID-19 or influenza (identified by hospital diagnosis or nucleic acid test).

MAIN OUTCOMES AND MEASURES

Hospital diagnosis of arterial thromboembolism (acute myocardial infarction or ischemic stroke) and venous thromboembolism (deep vein thrombosis or pulmonary embolism) within 90 days. Outcomes were ascertained through July 2019 for patients with influenza and through August 2021 for patients with COVID-19. Propensity scores with fine stratification were developed to account for differences between the influenza and COVID-19 cohorts. Weighted Cox regression was used to estimate the adjusted hazard ratios (HRs) for outcomes during each COVID-19 vaccine availability period vs the influenza period.

RESULTS

A total of 85 637 patients with COVID-19 (mean age, 72 [SD, 13.0] years; 50.5% were male) and 8269 with influenza (mean age, 72 [SD, 13.3] years; 45.0% were male) were included. The 90-day absolute risk of arterial thromboembolism was 14.4% (95% CI, 13.6%-15.2%) in patients with influenza vs 15.8% (95% CI, 15.5%-16.2%) in patients with COVID-19 before vaccine availability (risk difference, 1.4% [95% CI, 1.0%-2.3%]) and 16.3% (95% CI, 16.0%-16.6%) in patients with COVID-19 during vaccine availability (risk difference, 1.9% [95% CI, 1.1%-2.7%]). Compared with patients with influenza, the risk of arterial thromboembolism was not significantly higher among patients with COVID-19 before vaccine availability (adjusted HR, 1.04 [95% CI, 0.97-1.11]) or during vaccine availability (adjusted HR, 1.07 [95% CI, 1.00-1.14]). The 90-day absolute risk of venous thromboembolism was 5.3% (95% CI, 4.9%-5.8%) in patients with influenza vs 9.5% (95% CI, 9.2%-9.7%) in patients with COVID-19 before vaccine availability (risk difference, 4.1% [95% CI, 3.6%-4.7%]) and 10.9% (95% CI, 10.6%-11.1%) in patients with COVID-19 during vaccine availability (risk difference, 5.5% [95% CI, 5.0%-6.1%]). Compared with patients with influenza, the risk of venous thromboembolism was significantly higher among patients with COVID-19 before vaccine availability (adjusted HR, 1.60 [95% CI, 1.43-1.79]) and during vaccine availability (adjusted HR, 1.89 [95% CI, 1.68-2.12]).

CONCLUSIONS AND RELEVANCE

Based on data from a US public health surveillance system, hospitalization with COVID-19 before and during vaccine availability, vs hospitalization with influenza in 2018-2019, was significantly associated with a higher risk of venous thromboembolism within 90 days, but there was no significant difference in the risk of arterial thromboembolism within 90 days.

Risk factors for portal vein thrombosis or venous thromboembolism in a large cohort of hospitalized cirrhotic patients

BACKGROUND

Portal vein thrombosis (PVT) and venous thromboembolism (VTE) are fearsome complications of liver cirrhosis.

OBJECTIVES

To assess the prevalence and the main risk factors for venous thrombotic complications in hospitalized cirrhotic patients.

PATIENTS/METHODS

We retrospectively reviewed electronic administrative discharge data of 19461 cirrhotic patients hospitalized over a 35-year period; univariate and multivariate logistic regression was used to asses risk factors for PVT or VTE and their impact on hospital stay and mortality.

RESULTS

382 out of 7445 patients (5.1%) were diagnosed with PVT and 95 (1.3%) with VTE. Liver cirrhosis complications were observed in 45% of patients. Hepatic encephalopathy (HE) (OR 13.88 [10.76-17.98] p < 0.0001), endoscopic signs of portal hypertension (OR 1.33 [1.02-1.75] p = 0.02), hepatocellular carcinoma (HCC) (OR 4.59 [3.6-5.84] p < 0.0001), diabetes (OR 1.68 [1.27-2.22] p = 0.0001), abdominal surgery/invasive procedures (OR 2.03 [1.56-2.64] p < 0.0001) emerged as independent predictors of PVT. Higher risk of VTE was observed in patients with HE (OR 3.21 [1.78-5.79] p < 0.0001), HCC (OR 1.98 [1.23-3.19] p = 0.002) or other tumors (OR 2.48 [1.42-4.32] p = 0.001), acute illnesses (infections OR 3.01 [1.84-5.05] p = 0.0001; cardiac/respiratory insufficiency OR 2.4 [1.27-4.53] p = 0.003; acute myocardial infarction/stroke OR 7.86 [1.76-35.12] p = 0.003). VTE was the only independent predictor of in-hospital mortality (OR 4.45 [1.05-18.81] p = 0.042).

CONCLUSIONS

Liver disease complications related to portal hypertension, HCC or other tumors, diabetes, acute illnesses (i.e. infections, cardiac/pulmonary insufficiency, acute myocardial infarction/stroke) and abdominal interventions are associated with increased risk of PVT or VTE in hospitalized cirrhotic patients, and should be considered to define personalized preemptive approaches.

Large-scale evidence generation and evaluation across a network of databases for type 2 diabetes mellitus (LEGEND-T2DM): a protocol for a series of multinational, real-world comparative cardiovascular effectiveness and safety studies

INTRODUCTION

Therapeutic options for type 2 diabetes mellitus (T2DM) have expanded over the last decade with the emergence of cardioprotective novel agents, but without such data for older drugs, leaving a critical gap in our understanding of the relative effects of T2DM agents on cardiovascular risk.

METHODS AND ANALYSIS

The large-scale evidence generations across a network of databases for T2DM (LEGEND-T2DM) initiative is a series of systematic, large-scale, multinational, real-world comparative cardiovascular effectiveness and safety studies of all four major second-line anti-hyperglycaemic agents, including sodium-glucose co-transporter-2 inhibitor, glucagon-like peptide-1 receptor agonist, dipeptidyl peptidase-4 inhibitor and sulfonylureas. LEGEND-T2DM will leverage the Observational Health Data Sciences and Informatics (OHDSI) community that provides access to a global network of administrative claims and electronic health record data sources, representing 190 million patients in the USA and about 50 million internationally. LEGEND-T2DM will identify all adult, patients with T2DM who newly initiate a traditionally second-line T2DM agent. Using an active comparator, new-user cohort design, LEGEND-T2DM will execute all pairwise class-versus-class and drug-versus-drug comparisons in each data source, producing extensive study diagnostics that assess reliability and generalisability through cohort balance and equipoise to examine the relative risk of cardiovascular and safety outcomes. The primary cardiovascular outcomes include a composite of major adverse cardiovascular events and a series of safety outcomes. The study will pursue data-driven, large-scale propensity adjustment for measured confounding, a large set of negative control outcome experiments to address unmeasured and systematic bias.

ETHICS AND DISSEMINATION

The study ensures data safety through a federated analytic approach and follows research best practices, including prespecification and full disclosure of results. LEGEND-T2DM is dedicated to open science and transparency and will publicly share all analytic code from reproducible cohort definitions through turn-key software, enabling other research groups to leverage our methods, data and results to verify and extend our findings.

COVID-19 is associated with higher risk of venous thrombosis, but not arterial thrombosis, compared with influenza: Insights from a large US cohort

Introduction

Infection with SARS-CoV-2 is typically compared with influenza to contextualize its health risks. SARS-CoV-2 has been linked with coagulation disturbances including arterial thrombosis, leading to considerable interest in antithrombotic therapy for Coronavirus Disease 2019 (COVID-19). However, the independent thromboembolic risk of SARS-CoV-2 infection compared with influenza remains incompletely understood. We evaluated the adjusted risks of thromboembolic events after a diagnosis of COVID-19 compared with influenza in a large retrospective cohort.

Methods

We used a US-based electronic health record (EHR) dataset linked with insurance claims to identify adults diagnosed with COVID-19 between April 1, 2020 and October 31, 2020. We identified influenza patients diagnosed between October 1, 2018 and April 31, 2019. Primary outcomes [venous composite of pulmonary embolism (PE) and acute deep vein thrombosis (DVT); arterial composite of ischemic stroke and myocardial infarction (MI)] and secondary outcomes were assessed 90 days post-diagnosis. Propensity scores (PS) were calculated using demographic, clinical, and medication variables. PS-adjusted hazard ratios (HRs) were calculated using Cox proportional hazards regression.

Results

There were 417,975 COVID-19 patients (median age 57y, 61% women), and 345,934 influenza patients (median age 47y, 66% women). Compared with influenza, patients with COVID-19 had higher venous thromboembolic risk (HR 1.53, 95% CI 1.38–1.70), but not arterial thromboembolic risk (HR 1.02, 95% CI 0.95–1.10). Secondary analyses demonstrated similar risk for ischemic stroke (HR 1.11, 95% CI 0.98–1.25) and MI (HR 0.93, 95% CI 0.85–1.03) and higher risk for DVT (HR 1.36, 95% CI 1.19–1.56) and PE (HR 1.82, 95% CI 1.57–2.10) in patients with COVID-19.

Conclusion

In a large retrospective US cohort, COVID-19 was independently associated with higher 90-day risk for venous thrombosis, but not arterial thrombosis, as compared with influenza. These findings may inform crucial knowledge gaps regarding the specific thromboembolic risks of COVID-19.

Validation Study of Algorithms to Identify Malignant Tumors and Serious Infections in a Japanese Administrative Healthcare Database

BACKGROUND

This retrospective observational study validated case-finding algorithms for malignant tumors and serious infections in a Japanese administrative healthcare database.

METHODS

Random samples of possible cases of each disease (January 2015-January 2018) from two hospitals participating in the Medical Data Vision Co., Ltd. (MDV) database were identified using combinations of ICD-10 diagnostic codes and other procedural/billing codes. For each disease, two physicians identified true cases among the random samples of possible cases by medical record review; a third physician made the final decision in cases where the two physicians disagreed. The accuracy of case-finding algorithms was assessed using positive predictive value (PPV) and sensitivity.

RESULTS

There were 2,940 possible cases of malignant tumor; 180 were randomly selected and 108 were identified as true cases after medical record review. One case-finding algorithm gave a high PPV (64.1%) without substantial loss in sensitivity (90.7%) and included ICD-10 codes for malignancy and photographing/imaging. There were 3,559 possible cases of serious infection; 200 were randomly selected and 167 were identified as true cases after medical record review. Two case-finding algorithms gave a high PPV (85.6%) with no loss in sensitivity (100%). Both case-finding algorithms included the relevant diagnostic code and immunological infection test/other related test and, of these, one also included pathological diagnosis within 1 month of hospitalization.

CONCLUSIONS

The case-finding algorithms in this study showed good PPV and sensitivity for identification of cases of malignant tumors and serious infections from an administrative healthcare database in Japan.

Incidence of venous thromboembolism in patients with obstructive sleep apnea: a cohort study

BACKGROUND

Previous studies suggesting that obstructive sleep apnea (OSA) may be an independent risk factor for venous thromboembolism (VTE) have been limited by reliance on administrative data and lack of adjustment for clinical variables, including obesity.

RESEARCH QUESTION

Does OSA confer an independent risk of incident VTE among a large clinical cohort referred for sleep disordered breathing evaluation?

STUDY DESIGN AND METHODS

We analyzed the clinical outcomes of 31,309 patients undergoing overnight polysomnography within a large hospital system. We evaluated the association of OSA severity with incident VTE using Cox proportional hazards modeling accounting for age, sex, body mass index (BMI), and common comorbid conditions.

RESULTS

Patients were of mean age 50.4 years and 50.1% female. There were 1,791 VTE events identified over a mean follow-up of 5.3 years. In age and sex-adjusted analyses, each 10 event/hr increase in the apnea hypopnea index (AHI) was associated with a 4% increase in incident VTE risk (hazard ratio [HR] 1.04, 95% confidence interval [CI] 1.02-1.05). After adjusting for BMI, this association disappeared (HR 1.01, 95% CI 0.99-1.03). In contrast, nocturnal hypoxemia had an independent association with incident VTE. Patients with >50% sleep time spent with oxyhemoglobin saturation <90% are at 48% increased VTE risk compared to those without nocturnal hypoxemia (HR 1.48, 95% CI 1.16-1.69).

INTERPRETATION

In this large cohort, we found that patients with more severe OSA as measured by the AHI are more likely to have incident VTE. Adjusted analyses suggest that this association is explained due to confounding by obesity. However, severe nocturnal hypoxemia may be a mechanism by which OSA heightens VTE risk.

COVID-19 is associated with higher risk of venous thrombosis, but not arterial thrombosis, compared with influenza: Insights from a large US cohort

Introduction

Infection with SARS-CoV-2 is typically compared with influenza to contextualize its health risks. SARS-CoV-2 has been linked with coagulation disturbances including arterial thrombosis, leading to considerable interest in antithrombotic therapy for Coronavirus Disease 2019 (COVID-19). However, the independent thromboembolic risk of SARS-CoV-2 infection compared with influenza remains incompletely understood. We evaluated the adjusted risks of thromboembolic events after a diagnosis of COVID-19 compared with influenza in a large retrospective cohort.

Methods

We used a US-based electronic health record (EHR) dataset linked with insurance claims to identify adults diagnosed with COVID-19 between April 1, 2020 and October 31, 2020. We identified influenza patients diagnosed between October 1, 2018 and April 31, 2019. Primary outcomes [venous composite of pulmonary embolism (PE) and acute deep vein thrombosis (DVT); arterial composite of ischemic stroke and myocardial infarction (MI)] and secondary outcomes were assessed 90 days post-diagnosis. Propensity scores (PS) were calculated using demographic, clinical, and medication variables. PS-adjusted hazard ratios (HRs) were calculated using Cox proportional hazards regression.

Results

There were 417,975 COVID-19 patients (median age 57y, 61% women), and 345,934 influenza patients (median age 47y, 66% women). Compared with influenza, patients with COVID-19 had higher venous thromboembolic risk (HR 1.53, 95% CI 1.38–1.70), but not arterial thromboembolic risk (HR 1.02, 95% CI 0.95–1.10). Secondary analyses demonstrated similar risk for ischemic stroke (HR 1.11, 95% CI 0.98–1.25) and MI (HR 0.93, 95% CI 0.85–1.03) and higher risk for DVT (HR 1.36, 95% CI 1.19–1.56) and PE (HR 1.82, 95% CI 1.57–2.10) in patients with COVID-19.

Conclusion

In a large retrospective US cohort, COVID-19 was independently associated with higher 90-day risk for venous thrombosis, but not arterial thrombosis, as compared with influenza. These findings may inform crucial knowledge gaps regarding the specific thromboembolic risks of COVID-19.

Long-term safety of extended levonorgestrel-containing oral contraceptives in the United States

OBJECTIVES

To compare the safety profile of Seasonique, a 91-day levonorgestrel-containing combined oral contraceptive (COC_LNG), to 28-day COC_LNG regarding the risk of venous thromboembolism (VTE) and arterial thromboembolism (ATE).

STUDY DESIGN

A new user cohort study was conducted in a US health care database from 2006 to 2017. Each 91-day COC_LNG treatment episode in females was matched to up to four 28-day COC_LNG treatment episodes by propensity score. We identified VTE cases in either (1) an inpatient setting with ICD-9 and ICD-10 diagnosis codes of PE and/or DVT in the primary position, or (2) an outpatient setting with ICD-9 or ICD-10 diagnosis codes of DVT in conjunction with an anticoagulant medication dispensing or alteplase (thrombolytic) during the 30-day period following the date of DVT diagnosis. VTE was validated using medical records. We assessed the study endpoints in the two cohorts using incidence rates and Cox proportional hazards models adjusted for potential confounders.

RESULTS

Of the 25,593 treatment episodes in 91-day COC_LNG and 76,586 treatment episodes in 28-day COC_LNG, 35 and 68 patients had VTEs, respectively, corresponding to a hazard ratio (HR) of 1.40 (95% confidence interval [CI], 0.90-2.19). The VTE algorithm had a positive predictive value of 76.4% (95% CI, 66.2%-84.8%). ATEs were recorded in 13 and 28 episodes, respectively, with a corresponding HR of 1.21 (95% CI, 0.58-2.53).

CONCLUSIONS

These results do not indicate a significant difference between 91-day COC_LNG and 28-day COC_LNG in terms of VTE or ATE risk.

IMPLICATIONS

Compared to use of 28-day COC_LNG, use of 91-day extended COC_LNG was not associated with a significant difference in risk of venous and arterial thromboembolism.

COVID-19 Outcomes in Patients With Systemic Autoimmune Rheumatic Diseases Compared to the General Population: A US Multicenter, Comparative Cohort Study

OBJECTIVE

Patients with systemic autoimmune rheumatic diseases (ARDs) continue to be concerned about risks of severe coronavirus disease 2019 (COVID-19) outcomes. This study was undertaken to evaluate the risks of severe outcomes in COVID-19 patients with systemic ARDs compared to COVID-19 patients without systemic ARDs.

METHODS

Using a large multicenter electronic health record network, we conducted a comparative cohort study of patients with systemic ARDs diagnosed as having COVID-19 (identified by diagnostic code or positive molecular test result) compared to patients with COVID-19 who did not have systemic ARDs, matched for age, sex, race/ethnicity, and body mass index (primary matched model) and additionally matched for comorbidities and health care utilization (extended matched model). Thirty-day outcomes were assessed, including hospitalization, intensive care unit (ICU) admission, mechanical ventilation, acute renal failure requiring renal replacement therapy, ischemic stroke, venous thromboembolism, and death.

RESULTS

We initially identified 2,379 COVID-19 patients with systemic ARDs (mean age 58 years; 79% female) and 142,750 comparators (mean age 47 years; 54% female). In the primary matched model (2,379 patients with systemic ARDs and 2,379 matched comparators with COVID-19 without systemic ARDs), patients with systemic ARDs had a significantly higher risk of hospitalization (relative risk [RR] 1.14 [95% confidence interval (95% CI) 1.03-1.26]), ICU admission (RR 1.32 [95% CI 1.03-1.68]), acute renal failure (RR 1.81 [95% CI 1.07-3.07]), and venous thromboembolism (RR 1.74 [95% CI 1.23-2.45]) versus comparators but did not have a significantly higher risk of mechanical ventilation or death. In the extended model, all risks were largely attenuated, except for the risk of venous thromboembolism (RR 1.60 [95% CI 1.14-2.25]).

CONCLUSION

Our findings indicate that COVID-19 patients with systemic ARDs may be at a higher risk of hospitalization, ICU admission, acute renal failure, and venous thromboembolism when compared to COVID-19 patients without systemic ARDs. These risks may be largely mediated by comorbidities, except for the risk of venous thromboembolism.

Incidence of Venous Thromboembolism in Patients With Dermatologist-Diagnosed Chronic Inflammatory Skin Diseases

Importance

Several studies have linked chronic inflammatory skin diseases (CISDs) with venous thromboembolism (VTE) in a range of data sources with mixed conclusions.

Objective

To examine the incidence of VTE in patients with vs without CISD.

Design, Setting, and Participants

A cohort study using commercial insurance claims data from a nationwide US health care database from January 1, 2004, through 2019 was conducted. A total of 158 123 patients with dermatologist-recorded psoriasis, atopic dermatitis, alopecia areata, vitiligo, or hidradenitis suppurativa were included. Risk-set sampling identified patients without a CISD. Patient follow-up lasted until the first of the following occurred: VTE, death, disenrollment, or end of data stream.

Exposures

Patients with vs without CISD.

Main Outcomes and Measures

Venous thromboembolism events were identified with validated algorithms. Incidence rates were computed before and after 1:1 propensity-score matching to account for VTE risk factors. Hazard ratios were estimated to compare the incidence of VTE in the CISD vs non-CISD cohorts.

Results

A total of 158 123 patients were identified with CISD: with psoriasis (n = 96 138), atopic dermatitis (n = 30 418), alopecia areata (n = 17 889), vitiligo (n = 7735), or HS (n = 5934); 9 patients had 2 of these conditions. A total of 1 570 387 patients were without a CISD. The median follow-up time was 1.9 years (interquartile range, 0.8-4.0 years) in patients with CISD. The incidence rate (per 1000 person-years) of outpatient or inpatient VTE was 1.57 in psoriasis, 1.83 in atopic dermatitis, 0.94 in alopecia areata, 0.93 in vitiligo, 1.65 in HS and 1.53 in CISD overall, compared with 1.76 in patients without a CISD. Incidence rates increased in patients aged 50 years or older (2.3 per 1000 person-years) and decreased in those aged 18 to 49 years (0.8 per 1000 person-years). After propensity-score matching to patients without a CISD, the hazard ratio (HR) of VTE was 0.86 (95% CI, 0.75-0.99) in psoriasis, 1.19 (95% CI, 0.95-1.48) in atopic dermatitis, 0.97 (95% CI, 0.65-1.46) in alopecia areata, 0.90 (95% CI, 0.49-1.65) in vitiligo, 1.64 (95% CI, 0.82-3.27) in hidradenitis suppurativa, and 0.94 (95% CI, 0.84-1.05) in CISD overall.

Conclusions and Relevance

In this large-scale cohort study, CISDs were not associated with an increased incidence of VTE after controlling for relevant VTE risk factors in a representative dermatology patient population.

Validation of an electronic algorithm for Hodgkin and non-Hodgkin lymphoma in ICD-10-CM

PURPOSE

Lymphoma is a health outcome of interest for drug safety studies. Studies using administrative claims data require the accurate identification of lymphoma cases. We developed and validated an International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM)-based algorithm to identify lymphoma in healthcare claims data.

METHODS

We developed a three-component algorithm to identify patients aged ≥15 years who were newly diagnosed with Hodgkin (HL) or non-Hodgkin (NHL) lymphoma from January 2016 through July 2018 among members of four Data Partners within the FDA's Sentinel System. The algorithm identified potential cases as patients with ≥2 ICD-10-CM lymphoma diagnosis codes on different dates within 183 days; ≥1 procedure code for a diagnostic procedure (e.g., biopsy, flow cytometry) and ≥1 procedure code for a relevant imaging study within 90 days of the first lymphoma diagnosis code. Cases identified by the algorithm were adjudicated via chart review and a positive predictive value (PPV) was calculated.

RESULTS

We identified 8723 potential lymphoma cases via the algorithm and randomly sampled 213 for validation. We retrieved 138 charts (65%) and adjudicated 134 (63%). The overall PPV was 77% (95% confidence interval: 69%-84%). Most cases also had subtype information available, with 88% of cases identified as NHL and 11% as HL.

CONCLUSIONS

Seventy-seven percent of lymphoma cases identified by an algorithm based on ICD-10-CM diagnosis and procedure codes and applied to claims data were true cases. This novel algorithm represents an efficient, cost-effective way to target an important health outcome of interest for large-scale drug safety and public health surveillance studies.

Impact of a digital Modified Checklist for Autism in Toddlers-Revised on likelihood and age of autism diagnosis and referral for developmental evaluation

LAY ABSTRACT

This was a project in primary care for young children (1-2 years old). We tested a parent questionnaire on a tablet. This tablet questionnaire asked questions to see whether the child may have autism. We compared the paper and pencil version of the questionnaire to the tablet questionnaire. We read the medical charts for the children until they were 4 years old to see whether they ended up having autism. We found that doctors were more likely to recommend an autism evaluation when a parent used the tablet questionnaire. We think that the tablet's automatic scoring feature helped the doctors. We also think that the doctors benefited from the advice the tablet gave them.