Mortality Trends in Pre-COVID-19 and COVID-19 Eras Among Oldest Veterans.

Background: The COVID-19 pandemic has had a profound impact on older adults, particularly those with existing comorbidities. To inform targeted healthcare strategies for this heterogeneous group, this study seeks to analyze and compare mortality trends among various geriatric age groups within the Veterans Affairs (VA) Health Care System, both during the COVID-19 era and the pre-COVID era, while accounting for demographic and clinical factors such as age, gender, race, and comorbidities.

Methods: A retrospective cohort study using Veterans Affairs Informatics and Computing Infrastructure (VINCI) data. Two samples were analyzed: Veterans alive during the pre-COVID era (January 2019 - December 2019) and during the COVID era (January 2020 - December 2020). Propensity score matching was used to control for age, sex, race, BMI, and comorbidities.

Results: The primary outcome was mortality. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to compare mortality across age groups. Unmatched analyses, adjusted for age, sex, race, BMI, and comorbidities, showed that mortality significantly increased during the COVID era for age groups 70-79 (OR 1.38), 80-89 (OR 1.14), and 90-99 (OR 1.20), all with p-values < 0.0001. No significant increase was observed in centenarians (OR 1.103, 95% CI 0.90-1.35, p=0.345). Matched analysis confirmed these findings.

Conclusions: In a large cohort of older Veterans, COVID-19 had a significant impact on mortality in older adults aged 70-99, highlighting the need for targeted public health interventions. The lack of significant increase in mortality for centenarians is notable and warrants further study to identify possible protective factors in this unique population.