BACKGROUND: Several early-life factors have been associated with higher risk of developing dementia. It is unclear whether season of birth (SOB) can affect cognitive aging in older adults or not. OBJECTIVE: We aimed to study the association of SOB with the level of cognitive performance as well as with the rate of cognitive decline. METHODS: We studied 70,203 individuals who participated in the Survey of Health, Aging and Retirement in Europe. Cognition was measured with tests on verbal fluency and immediate and delayed recall. We assessed the association of SOB with the level of cognitive performance using multiple linear regression and with the rate of cognitive decline using linear mixed-effects models. RESULTS: When compared to individuals born in winter and adjusted for sociodemographic and health-related characteristics, being born in summer was associated with a higher level of delayed recall (B 0.05; 95%CI 0.01 to 0.09) and verbal fluency (B 0.15; 95%CI 0.00 to 0.29) and being born in fall with a higher level of immediate recall (B 0.04; 95%CI 0.01 to 0.08) and verbal fluency (B 0.15; 95%CI 0.01 to 0.29). Individuals born in summer had a higher yearly decline in delayed recall (B -0.005; 95%CI -0.009 to 0.000), while the scores in delayed recall in participants born in spring showed an inverse trend (B 0.005; 95%CI 0.000 to 0.010). CONCLUSION: Individuals born in winter seem to carry a life-long disadvantage in a lower level of cognitive performance; however, being born in winter does not seem to affect the rate of cognitive decline.

2nd Faculty of Medicine Charles University Prague Czech Republic

3rd Faculty of Medicine Charles University Prague Czech Republic

National Institute of Mental Health Klecany Czech Republic

Citace poskytuje Crossref.org

Season of birth has no effect on symptoms of depression and anxiety in older adults