Different cutoff points to diagnose low muscle mass and prediction of osteoporosis in postmenopausal women

Abstract

Objective: This study aimed to verify which of the different cutoff points of low muscle mass (LMM) based on appendicular lean mass (ALM) is associated with osteoporosis in postmenopausal women (PMW). Methods: Cross-sectional study. PMW (n = 355) were classified for the presence of osteoporosis (score <−2.5 standard deviations) at the femoral neck and lumbar spine and LMM (three cutoff points: ALM < 15 kg; ALM/height2 [ALM index] <5.67 kg/m2 and ratio between ALM and body mass index [ALMBMI] <0.512). Results: After adjustments for confounding factors, binary logistic regression showed that ALM and ALM index were associated with osteoporosis at the lumbar spine (odds ratio [OR] = 5.3 [95% CI: 2.3-12.5] and OR = 2.5 [95% CI: 1.0-6.2], respectively) and only ALM was associated with osteoporosis at the femoral neck (OR = 16.1 [95% CI: 4.1-62.5]). When women were classified as having osteoporosis in at least one site, only ALM was associated with osteoporosis (OR = 7.7 [95% CI: 3.3-15.6]). There was no association between ALMBMI and osteoporosis. The predictive value of ALM for osteoporosis decreased after BMI or height were included as a covariate in the model. Conclusion: Absolute ALM (<15 kg) seems to be the most suitable for predicting osteoporosis based on LMM in PMW.

Relationship of sarcopenia with bone geometry and mass among postmenopausal women

“…These associations are consistent with previous studies. 22,[43][44][45] This suggests that lower muscle function test performance may be "indirect" indicators of low bone strength (ie, impaired bone geometry and low aBMD). Furthermore, 5-STS and dynamometry are simple, quick, low cost, easy to apply, have good reproducibility, and can be used in a variety of clinical settings, making them ideal for outpatient clinics.…”

“…16 Indeed, muscle mass and function (strength and power) are important risk factors for low BMD, impaired bone geometry 21 and hip fracture. 22,23 Moreover, sarcopenia (progressive loss of muscle mass and strength with advancing age) is associated with increased risk of fractures, most frequently in the hip and in people with frailty. [23][24][25] Geometric adaptations (increased periosteal apposition) appear to occur during the menopausal transition, which may help to maintain bone strength following menopause.…”

“…Because of the interconnection between muscle and bone (mechanical and physiological), 13-20 the simultaneous deterioration of skeletal muscle (and function) and bone increases the risk of fracture 16 . Indeed, muscle mass and function (strength and power) are important risk factors for low BMD, impaired bone geometry 21 and hip fracture 22,23 . Moreover, sarcopenia (progressive loss of muscle mass and strength with advancing age) is associated with increased risk of fractures, most frequently in the hip and in people with frailty 23–25 …”

Associations between bone mass, hormone levels, and body composition in postmenopausal women

“…Menopause-related hormonal changes predispose women to bone loss, and the identification of risk factors in this population can help in the early diagnosis and preventive measures against low bone mass. Previous data suggest that low muscle mass and, particularly, appendicular lean mass (ALM) can be used as a predictor of postmenopausal osteoporosis considering the available sarcopenia cutoff points 23,24 . However, using the same cutoff indicated for sarcopenia assessment may not be sufficient for the early identification of women at higher risk for low bone mass after menopause.…”

“…Previous data suggest that low muscle mass and, particularly, appendicular lean mass (ALM) can be used as a predictor of postmenopausal osteoporosis considering the available sarcopenia cutoff points. 23,24 However, using the same cutoff indicated for sarcopenia assessment may not be sufficient for the early identification of women at higher risk for low bone mass after menopause. Taking these aspects into consideration, the present study aimed to assess the impact of ALM on BMD in apparently healthy postmenopausal women.…”