Joint association of depression and physical activity with pre-frailty and frailty among European middle-aged and older adults

BACKGROUND: Frailty is a growing concern in ageing populations, linked to physical and mental health. Although physical activity (PA) attenuates frailty and depression, limited research has explored their joint association with frailty. This study investigated the joint association of depression and PA with pre-frailty and frailty among European adults ≥50 years. METHODS: Cross-sectional data from 39,647 participants in wave 8 of the Survey of Health, Ageing and Retirement in Europe (SHARE). Frailty was assessed with SHARE-Frailty Instrument (SHARE-FI). Depression was measured with EURO-D scale, and PA was categorised into four levels based on self-reported frequency. Multinomial logistic regressions examined the joint associations of depression and PA on frailty status. RESULTS: Depression was associated with higher odds (OR) of both pre-frailty and frailty. PA showed a protective effect, even among individuals with depression. The biggest odds reduction occurred in participants without depression and with very high PA (pre-frailty: OR = 0.016, 95% CI = 0.013, 0.019; frailty: OR = 0.001; 95% CI = 0.000, 0.001) compared to participants with depression and very low PA levels. CONCLUSIONS: PA is associated with lower odds of pre-frailty and frailty, even among individuals with depressive symptoms. This supports considering both PA and depressive symptoms when addressing frailty risk in ageing populations.