Résumé
Life satisfaction (LS) is associated with lower morbidity and mortality. However, the evidence linking LS to dementia remains limited, with no studies from Europe. Prior studies also differ in the measurement of LS, dementia ascertainment and follow-up length. This study examined the prospective association between LS and dementia risk in samples of older adults from 15 European countries and combined the findings with the published literature in a meta-analysis.
Participants from the English Longitudinal Study of Ageing (ELSA; N = 6979; 56.1% female; Meanage = 65.35) and the Survey of Health, Ageing and Retirement in Europe (SHARE; N = 24,098; 55.8% female; Meanage = 64.50) reported their LS at baseline (2004-05 for ELSA; 2006-10 for SHARE). Dementia was ascertained through self-reported diagnosis or the Informant Questionnaire on Cognitive Decline in the Elderly up to 2023 for ELSA and with self and/or proxy-reported doctor diagnosis up to 2022 for SHARE.
In both samples, accounting for age and sex, greater LS was associated with a lower risk of dementia (ELSA; hazard ratio [HR] = 0.80, 95% CI = 0.73-0.87; SHARE; HR = 0.82, 95% CI = 0.79-0.86). The association persisted, accounting for other dementia risk factors (physical inactivity, smoking, obesity, diabetes, hypertension and depression), and was similar across sociodemographic groups and European regions. The random-effects meta-analysis (k = 7; total N = 74 392) supported the association between LS and lower dementia risk (HR = 0.76, 95% CI = 0.67-0.84).
Across Europe and other world regions, the findings are consistent that LS is related to a lower risk of dementia. LS could be a valuable target for promoting healthier cognitive outcomes in older adults.