Abstract
BACKGROUND: Older adults were among the most affected by the COVID-19 pandemic, facing greater vulnerability to infection, hospitalization, and post-infection sequelae. However, evidence on its multidimensional impact on healthy aging remains limited, particularly in Latin America. This study examined the association of COVID-19 infection, hospitalization, and vaccination with healthy aging and functional impairment among older Mexican adults. METHODS: We analyzed longitudinal data from the Mexican Health and Aging Study (MHAS), comparing pre-pandemic (2018) and post-pandemic (2021) waves. Two outcomes were assessed: the Healthy Aging Score (HAS), a composite indicator of physical, mental, and social functioning (mean = 50, SD = 10), and functional impairment, defined as any limitation in basic or multiple instrumental activities of daily living. Random-effects regression models estimated associations with self-reported COVID-19 infection, hospitalization, and vaccination, adjusting for sociodemographic and health covariates. RESULTS: The sample included 8,239 participants (mean age = 72.5 years; 55.9% women). Those reporting prior infection were younger and had higher BMI. COVID-19-related hospitalization was significantly associated with lower HAS (β = -1.96; 95% CI - 3.65 to - 0.26). Infection and vaccination were not significantly associated with HAS. However, vaccination was linked to a reduced likelihood of functional impairment (OR = 0.75; 95% CI 0.53 to 0.95). CONCLUSIONS: Hospitalization due to COVID-19 was associated with poorer multidimensional aging outcomes, whereas vaccination appeared protective against functional decline. These findings highlight the importance of preventive strategies and sustained vaccination coverage to preserve functionality and promote healthy aging in post-pandemic populations.