Risk factors for SARS-CoV-2 infection among the older adult population in Germany from June 2021 to April 2022

Background: Older people were among the most affected by the pandemic. However, there are few studies analyzing risk factors for COVID-19 infection in the outpatient older population during the pandemic in a population-representative manner. This study aims to identify COVID-19 infection-associated risk factors among older adults in Germany.

Methods: This is an analysis of the first wave of the population-representative survey on the health of older people in Germany (Gesundheit 65+) conducted between June 2021 and April 2022 by the Robert Koch Institute, including participants aged between 65 and 100. The present analysis includes 3,639 individuals who provided information on their infection status as ever having a COVID-19 infection confirmed by a test. We considered sociodemographic variables age, sex, and education, health risk factors (obesity, smoking, COVID-19 vaccination, and chronic diseases), and variables revealing regular face-to-face contact with other people (needing help to perform the basic activities of daily living (ADL), living in an assisted living facility, living with other people in the same household, having contact with a steady partner or partaking in face-to-face activities such as attending or receiving family or friends visits, attending religious or cultural events, attending paid or volunteer work or caring for children. We estimated the weighted prevalence with 95% confidence intervals (CI) of COVID-19 infection and conducted a univariable and multivariable logistic regression to explore the strength of association (odds ratio (OR)) between different variables with SARS-CoV-2 infection.

Results: The overall prevalence of COVID-19 infection was 3.9% (3.1-5.0). Prevalence of infection was higher among the oldest age group (85 years or older) (6.6%), individuals who did not get at least 2 doses of the vaccine against COVID-19 (17.5%), residents of assisted living facilities (17.6%), people who received help to perform ADL (8.2%), and non-smokers (4.3%). In multivariable analysis, living in an assisted living facility (OR 2.7; 95%CI 1.2-6.3), not having a vaccine against COVID-19 (OR 7.9; 95%CI 4.2-15.0), and receiving formal care (OR 2.9; 95%CI 1.3-6.3) were independently associated to a higher risk of COVID-19 infection.

Conclusion: During the years 2021-2022, free testing centers and a vaccination campaign against COVID-19 were established in Germany. Restrictive measures were slowly being lifted. By this time, multiple risk factors for COVID-19 infection had been studied in the overall population. However, this study fills a crucial gap by providing insights into the risk factors for the older portion of the population. Older adults most vulnerable to SARS-CoV-2 infection are people in need of formal care. Vaccination is the most effective preventive measure. Our results reinforce the importance of closing the knowledge gap concerning pandemic preparedness among people receiving long-term care in institutions or their homes in Germany.

Publication History

Article published online:
11 March 2025