Polyunsaturated fatty acids in relation to incident mobility disability and decline in gait speed; the Age, Gene/Environment Susceptibility-Reykjavik Study

BACKGROUND/OBJECTIVES: Low intake of long chain polyunsaturated fatty acids (PUFAs) are associated with physical disability; however, prospective studies of circulating PUFAs are scarce. We examined associations between plasma phospholipid n-3 and n-6 PUFAs with risk of incident mobility disability and gait speed decline. SUBJECTS/METHODS: Data are from a subgroup of the Age, Gene/Environment Susceptibility-Reykjavik Study, a population- based study of risk factors for disease and disability in old age. In this subgroup (n = 556, mean age 75.1 [+ or -]5.0 years, 47.5% men), plasma phospholipid PUFAs were assessed at baseline using gas chromatography. Mobility disability and usual gait speed were assessed at baseline and after 5.2 [+ or -]0.2 years. Mobility disability was defined as the following: having much difficulty, or being unable to walk 500 m or climb up 10 steps; decline in gait speed was defined as change [greater than or equal to] 0.10 m/s. Logistic regression analyses were performed to determine associations between sex-specific s.d. increments in PUFAs with risk of incident mobility disability and gait speed decline. Odds ratios (95% confidence intervals) adjusted for demographics, follow-up time, risk factors and serum vitamin D were reported. RESULTS: In women, but not men, every s.d. increment increase of total n-3 PUFAs and docosahexaenoic acid (DHA) was associated with lower mobility disability risk, odds ratio 0.48 (0.25; 0.93) and odds ratio 0.45 (0.24; 0.83), respectively. There was no association between n-6 PUFAs and the risk of incident mobility disability or gait speed decline. CONCLUSIONS: Higher concentrations of n-3 PUFAs and, particularly, DHA may protect women from impaired mobility but does not appear to have such an effect in men. European Journal of Clinical Nutrition (2015) 69, 489-493; doi: 10.1038/ejcn.2014.277; published online 14 January 2015
INTRODUCTION Aging is associated with loss of physical function. (1) With the aging of the general population and the considerable prevalence of older persons with mobility disability, identifying modifiable factors [...]