Health and sociodemographic determinants of excess mortality in Spanish nursing homes during the COVID-19 pandemic: a 2-year prospective longitudinal study.

Background: Age, multimorbidity, immunodeficiency and frailty of older people living in nursing homes make them vulnerable to COVID-19 and overall mortality.

Objective: To estimate overall and COVID-19 mortality parameters and analyse their predictive factors in older people living in nursing homes over a 2-year period.

Method: Design: A 2-year prospective longitudinal multicentre study was conducted between 2020 and 2022.

Setting: This study involved five nursing homes in Central Catalonia (Spain).

Participants: Residents aged 65 years or older who lived in the nursing homes on a permanent basis.

Measurements: Date and causes of deaths were recorded. In addition, sociodemographic and health data were collected. For the effect on mortality, survival curves were performed using the Kaplan-Meier method and multivariate analysis using Cox regression.

Results: The total sample of 125 subjects had a mean age of 85.10 years (standard deviation = 7.3 years). There were 59 (47.2%) deaths at 24 months (95% confidence interval, CI, 38.6-55.9) and 25 (20.0%) were due to COVID-19, mostly in the first 3 months. In multivariate analysis, functional impairment (hazard ratio, HR 2.40; 95% CI 1.33-4.32) was a significant risk factor for mortality independent of age (HR 1.17; 95% CI 0.69-2.00) and risk of sarcopenia (HR 1.40; 95% CI 0.63-3.12).

Conclusion: Almost half of this sample of nursing home residents died in the 2‑year period, and one fifth were attributed to COVID-19. Functional impairment was a risk factor for overall mortality and COVID-19 mortality, independent of age and risk of sarcopenia.