Evaluation of the Relationship Between Equol Production and the Risk of Locomotive Syndrome in Very Elderly Women

This study aimed to evaluate whether equol production status has an impact on the risk of locomotive syndrome in very elderly (≥85 years old) women. In this retrospective observational study, 116 very elderly women were recruited from those who lived in nursing homes for the elderly from June 2018 to November 2019. Equol production status was determined by measuring spot urine levels of equol, and risks of locomotive syndrome were evaluated by vulnerable fracture history and loco-check, a simple questionnaire comprising seven questions that can describe locomotive syndrome. Equol production (≥1 μmol/L in a spot urine sample) was found in 46 women (39.6%). Loss of equol production contributes to some lococheck items, which correlate with weakness of lower limb muscle strength (P < 0.05). In this study population, 57 women (49.1%) had previous vulnerable fractures. However, equol production status was not significantly related to the vulnerable fracture in this study population (P = 0.159). Equol production might contribute to the induction of locomotive syndrome, at least in part. However, equol deficiency as a mechanism of locomotive syndrome induction might not be the primary cause of a previous vulnerable fracture in very elderly women who live in nursing homes.