(A-217) Observed rate of safety outcomes, vaccinations, and healthcare utilization in elderly persons with Commercial vs Medicare Advantage insurance in a US Claims Database

Background: Many US claims data sources include Commercial claims (such as employer-sponsored insurance and Medigap/supplemental plans) or Medicare Advantage (MA) claims but lack Medicare Fee-for-Service (FFS) data, leading to potential gaps in healthcare resource utilization (HCRU) information for dual enrollees.

Objectives: To evaluate the utility of Commercial claims for real-world evidence (RWE) studies on vaccine safety in adults ≥65 by comparing the observed rates of safety outcomes, vaccinations, and HCRU in Commercial and MA cohorts.

Methods: This study utilized Optum’s de-identified Clinformatics® Data Mart Database (July 1, 2023 – June 30, 2024) and included adults aged ≥65 with at least 180 days of baseline enrollment. Commercial and MA enrollees were 1:1 exactly matched by age, and inverse probability of treatment weighting (IPTW) by propensity score was applied to ensure covariate balance between groups. Weighted incidence rates (IRs) per 100,000 person-years, along with 95% confidence intervals (CIs), were calculated for 10 safety outcomes among individuals without a prior diagnosis of the applicable condition during baseline. Weighted rates and 95% CIs were also calculated for vaccinations and HCRU outcomes.

Results: The cohort included 535,536 adults (267,768 individuals in each cohort). Over 85% of participants were younger than 74 years. The MA cohort had more females (56.5% vs. 46.1%) and higher mean (standard deviation) Deyo-Charlson Comorbidity Scores [1.63 (2.06) vs. 1.13 (1.71)]. After IPTW, most safety outcomes had lower IRs in the Commercial cohort vs. MA, with no difference for Guillain-Barre syndrome and transverse myelitis. The largest IR differences were observed for myocardial infarction and non-hemorrhagic stroke, with lower rates in the Commercial cohort vs. MA [695.11 (95% CI: 658.29, 733.98) vs 1049.43 (95% CI: 1009.74, 1090.68) and 384.66 (95% CI: 357.69, 413.66) vs. 571.47 (95% CI: 541.93, 602.62), respectively]. Vaccination rates for influenza, COVID-19, RSV, and zoster were lower in the Commercial cohort but higher for hepatitis A/B and Tdap. HCRU was lower in Commercial vs. MA [at least one outpatient visit: 92.3% vs. 95.4%].

Conclusions: Rates of safety outcomes, vaccinations, and HCRU were lower in the Commercial cohort despite matching for age and controlling for baseline health status. These findings suggest potential data gaps in Commercial claims and highlight the need for robust data sources like MA for RWE studies in adults ≥65.