Hyperhomocysteinemia causes various diseases including cardiovascular disease, osteoporotic fracture and dementia. Although there have been reports that hyperhomocysteinemia decreases physical performance, findings are inconsistent on the association of homocysteine, folate, vitamin B12 and physical performance. Considering that lower physical performance increases the risk of fall and fracture in the elderly, the effect of nutritional status on physical function must be clarified. This is a cross-sectional study conducted from April 2015 to November 2016. Eighty-six residents and users in five care facilities were evaluated for their blood homocysteine, folate and vitamin B12 concentrations and indices for physical performance; lower limb muscle strength, handgrip strength and gait speed. Analyses of physical performance were done in women only, considering the high proportion of women in the study population and the muscular gender difference. In the third tertile of plasma homocysteine concentration, handgrip strength was significantly lower than in the first tertile (p=0.027). In the first tertile of serum folate concentration, handgrip strength was significantly lower than in the third tertile (p=0.002). Although not statistically significant, lower limb muscle strength in the third tertile of folate was higher than in the first (p=0.061) and second (p=0.057) tertile. In the multiple regression analysis, however, only serum folate concentration was a significant contributor except for age. In subjects with their serum folate and vitamin B12 concentrations both exceeding the median, lower limb muscle strength was higher. Low serum folate concentration is a risk factor for lower physical performance independent of homocysteine in elderly women.
Keywords: elderly; folate; homocysteine; physical performance; vitamin B12.