Midarm Muscle Measurements May Be a Practical Tool for Osteoporosis Diagnosis

Midarm muscle circumference measurements are a practical, cost-effective tool that can be used to screen and diagnose early osteoporosis, especially in older men, according to research results published in the Archives of Gerontology and Geriatrics.

Currently, there is no convenient, cost-effective tool that screens for osteoporosis.

To assess the efficacy of midarm muscle circumference, researchers assessed data of 10,090 eligible patients enrolled in the National Health and Nutrition Examination Survey III conducted from 1988 to 1994.

Mean age of the study cohort was 47.8±19.1 years; 47.7% were men. Mean midarm muscle circumference (calculated as mid-upper arm circumference) – 0.3142 × triceps skinfold thickness – was 25.9±3.9 cm. Patients were divided into 3 tertiles based on circumference: tertile 1 with a circumference of 13.8 to 23.1 cm (n=3331), tertile 2 with a circumference of 23.2 to 26.8 cm (n=3361), and tertile 3 with a circumference of 26.9 to 44.1 cm (n=3398).

Logistic regression analysis identified decreased odds ratios (ORs) for osteoporosis in men with increased midarm muscle circumference. Four models were assessed for multiple covariates (age, sex, race, body mass index, serum high-density lipoprotein, serum fasting glucose, serum total cholesterol, serum total bilirubin, serum aspartate amino-transferase, congestive heart failure, stroke, malignancy, and smoking). In Model 1, unadjusted ORs for tertile 2 vs tertile 1 osteoporosis risk were 0.20 (95% CI, 0.13-0.30; P <.001) and 0.61 (95% CI, 0.49-0.75; P <.001) for men and women, respectively. After adjusting for multiple covariates, results of model 2 through model 4 indicated that these trends were persistent, with no significant associations between osteoporosis and midarm muscle circumference in women.

When stratified by obesity, investigators found that as midarm muscle circumference increased, ORs for osteoporosis decreased in both groups. Lower ORs of osteoporosis, as midarm muscle circumference tertiles, increased in patient groups with ages 40 to 64 years and 65 to 90 years.

Study results also demonstrated a negative correlation between osteoporosis as midarm muscle circumference increased, which remained consistent after multivariate adjusted analyses.

Study limitations included a lack of generalizability outside of the patient population represented in the National Health and Nutrition Examination Survey III dataset, limitations inherent in observational research, potential inaccuracies in included data, and possible confounding factors.

“[T]he present study corroborates that increased [midarm muscle circumference] may be an indicator for osteoporosis in [the population of men],” the researchers concluded. “Utilization of [midarm muscle circumference] as a surrogate for lean muscle mass is practical and convenient for detecting osteoporosis for older men.”

Reference

Chao Y-P, Kao T-W, Chen W-L, Peng T-C, Wu L-W. Mid-arm muscle circumference as an indicator of osteoporosis in community-dwelling older men. Arch Gerontol Geriatr. 2019;12(87):103998.