Stages of sarcopenia, bone mineral density, and the prevalence of osteoporosis in older women.

A better understanding of the relationship between osteoporosis and sarcopenia may help to develop effective preventive and therapeutic strategies. In the present study, the association between different stages of sarcopenia, BMD, and osteoporosis was examined. The salient findings indicate that a dose-response relationship exists between sarcopenia stages and bone-related phenotypes.

PURPOSE: To assess the association between sarcopenia stages, bone mineral density (BMD), and the prevalence of osteoporosis in older women.

METHODS: Two hundred thirty-four women (68.3 ± 6.3 years) underwent body composition and BMD measurements using dual-energy X-ray absorptiometry. Quadriceps isokinetic torque was evaluated, and the timed up-and-go test was conducted as a measure of function. Sarcopenia stages were classified according to European Working Group on Sarcopenia in Older People (EWGSOP): nonsarcopenia, presarcopenia, sarcopenia, and severe sarcopenia. Osteoporosis was defined as BMD value (hip or spine) 2.5 standard deviations below a young-adult reference population. Between-group differences were examined using ANOVA for continuous variables and chi-squared for categorical variables. Logistic regression was performed to evaluate the association between sarcopenia stages and osteoporosis.

RESULTS: Rates of osteoporosis were 15.8%, 19.2%, 35.3%, and 46.2% for nonsarcopenia, presarcopenia, sarcopenia, and severe sarcopenia, respectively (P = 0.002). Whole-body and femoral neck BMD values were significantly lower among all sarcopenia stages when compared to nonsarcopenia (all P values < 0.05, η2 p 0.113 to 0.109). The severe sarcopenia group also showed significantly lower lumbar spine BMD values and T-scores (both P values < 0.05; η2 p 0.035 and 0.037, respectively). When clustered, sarcopenia and severe sarcopenia exhibited lower BMD values for all sites (all P values < 0.01), and presented a significantly higher risk for osteoporosis (odds ratio 3.445; 95% CI 1.521-7.844).

CONCLUSION: The observed results provide support for the concept that a dose-response relationship exists between sarcopenia stages, BMD, and the presence of osteoporosis. These findings strengthen the clinical significance of the EWGSOP sarcopenia definition and indicate that severe sarcopenia should be viewed with attention by healthcare professionals.