Director, Pharmacoepidemiology Regeneron Pharmaceuticals, United States
Background: COVID-19 vaccines and treatments have potential adverse effects. Data on background incidence rates (IR) of cardiovascular (CV) events in high-risk populations are sparse and/or examine smaller databases. Here, we report background rates in large databases that can detect rare events and offer better generalizability. Background rates are critical for contextualizing safety signals arising from COVID-related interventions in investigational or real-world settings.
Objectives: To estimate the background rates of CV events in a population of US adults at high risk for progression to severe COVID-19 (“high-risk”).
Methods: Using data from medical and pharmacy claims in the HealthVerity (HV) and Optum datasets, we built a cohort of adults indexed on the date they first met CDC “high-risk” criteria between Jan 1, 2018 and July 31, 2021, regardless of COVID-19 diagnosis history. To estimate background rates of CV events prior to and during the pandemic, annual IR were estimated for acute myocardial infarction (AMI), pulmonary embolism (PE), myocarditis/pericarditis (MC/PC), non-hemorrhagic stroke (NHS), and hemorrhagic stroke (HS). No statistical comparisons were made. Updated results in HV through Dec 31, 2022 will be available at ICPE.
Results: The HV cohort included 12,513,664 patients. The most common criteria for high-risk classification were age ≥65 years (35.3%), obesity (18.6%), and diabetes mellitus (13.1%). Mean age in this cohort was 54.0 years; 56.8% were female. Optum data included 11,551,622 patients. The most common criteria for high-risk classification were age ≥65 years (55.7%), immunosuppression (14.9%), and obesity (10.1%). Mean age in this cohort was 60.8 years; 55.7% were female. Annual IR (95% CI) per 1000 person-years in HV data, for 2018-2021, were: AMI 7.9 (7.8, 8.0); 6.8 (6.8, 6.9); 5.9 (5.9, 6.0); and 7.2 (7.1, 7.3); PE: 3.0 (3.0, 3.1); 2.6 (2.5, 2.6); 2.4 (2.4, 2.4); and 3.0 (3.0, 3.1); MC/PC: 0.5 (0.5, 0.5); 0.4 (0.4, 0.4); 0.4 (0.3, 0.4); and 0.4 (0.4, 0.4); NHS: 6.5 (6.4, 6.6); 5.6 (5.6, 5.7); 4.7(4.7, 4.8); and 5.8 (5.7, 5.9); HS: 2.0 (2.0, 2.1); 1.7 (1.7, 1.7); 1.5 (1.4, 1.5); and 1.8 (1.8, 1.9). Rates were higher in Optum (results not shown) than HV but the trends were similar.
Conclusions: In our analysis of two large claims databases, background rates of CV events declined from 2018-2020 but increased in the first half of 2021, perhaps due to changes in healthcare resource use rather than in true incidence. Higher rates in Optum may be due to an older population, highlighting the importance of a multi-database approach when contextualizing potential safety signals from COVID-related and other interventions.
