Impact of premature natural menopause on body composition and physical function in elderly women: A Korean frailty and aging cohort study

Induced premature menopause accelerates the rate of body composition changes (decrease in skeletal muscle mass and increase in fat mass) and deteriorating physical function. However, few studies have focused on the impact of premature natural menopause. This study aimed to investigate the impact of age at natural menopause (ANM) on body composition and physical function in elderly women. Using data from the Korean Frailty and Aging Cohort Study, 765 community-dwelling elderly women aged 70 to 85 years who experienced natural menopause were recruited in this study. Body composition was measured using dual-energy X-ray absorptiometry. Physical function was evaluated by grip strength, the timed up and go test (TUG), and the short physical performance battery (SPPB). Participants were categorized into 4 groups according to their ANM: <40 (premature natural menopause, PNM), 40 to 44 (early natural menopause, ENM), 45 to 54 (normal menopause, NM), and ≥55 (late menopause, LM) years. There were no significant differences in the body composition parameters, such as the appendicular skeletal muscle mass index (PNM: 5.90 ± 0.90 vs ENM: 5.91 ± 0.70 vs NM: 5.85 ± 0.73 vs LM: 5.90 ± 0.75, kg/m(2), P = .75) and trunk fat mass index (PNM: 19.4 ± 3.9 vs ENM: 19.9 ± 4.4 vs NM: 19.9 ± 3.9 vs LM: 20.0 ± 3.8, %, P = .87) between the groups. In the physical function evaluation, there was no significant difference between the groups in grip strength (PNM: 19.8 ± 0.6 vs ENM: 20.3 ± 0.4 vs NM: 20.6 ± 0.2 vs LM: 20.6 ± 0.4, kg, P = .53). However, in the TUG (PNM: 11.8 ± 0.4 vs ENM: 10.3 ± 0.3 vs NM: 10.6 ± 0.1 vs LM: 10.2 ± 0.3, seconds, P < .01) and SPPB (PNM: 10.0 ± 0.2 vs ENM: 10.5 ± 0.2 vs NM: 10.6 ± 0.1 vs LM: 10.8 ± 0.2, points, P < .05), the PNM group showed significantly lower values than the other groups did. There was no difference in physical function between the groups except the PNM. Premature natural menopause did not affect the body composition in elderly women but was associated with physical function deterioration. Therefore, more attention should be paid to the prevention of the physical function deterioration caused by premature natural menopause in elderly women.