Sex differences in physical performance by age, educational level, ethnic groups and birth cohort : The Longitudinal Aging Study Amsterdam

BACKGROUND: Older women perform consistently poorer on physical performance tests compared to men. Risk groups for this "female disadvantage" in physical performance and it's development over successive birth cohorts are unknown. This is important information for preventive strategies aimed to enhance healthy aging in all older women. This study aims to longitudinal investigate whether there are risk groups for a more apparent female disadvantage and study its trend over successive birth cohorts. METHODS: Data of the Longitudinal Aging Study Amsterdam (LASA) were used. All participants were aged 55-65 years at baseline. Longitudinal data of two birth cohorts with baseline measurements in 1992/1993 (n = 966, 24 year follow-up) and 2002/2003 (n = 1002, 12 year follow-up) were included. Follow-up measurements were repeated every three/four years. Cross-sectional data of two additional cohorts were included to compare ethnic groups: a Dutch cohort (2012/2013, n = 1023) and a Migration cohort (2013/2014, n = 478) consisting of migrants with a Turkish/Moroccan ethnicity. RESULTS: Mixed model analysis showed that women aged 55 years and older had a lower age- and height-adjusted gait speed (-0.03 m/s; -0.063-0.001), chair stand speed (-0.05 stand/s; -0.071--0.033), handgrip strength (-14,8 kg; -15.69--13.84) and balance (OR = 0.71; 0.547-0.916) compared to men. The sex difference in handgrip strength diminished with increasing age, but remained stable for gait speed, chair stand speed and balance. In general, results were consistent across different, educational levels and Turkish/Moroccan ethnic groups and birth cohorts. CONCLUSIONS: There is a consistent "female disadvantage" in physical performance among older adults, which remains stable with increasing age (except for handgrip strength) and is consistent across different educational levels, ethnic groups and successive birth cohorts. So, no specific risk groups for the female disadvantage in physical performance were identified. Preventive strategies aimed to enhance healthy aging in older women are needed and should target all older women