Sterol metabolism and protein metabolism are differentially correlated with sarcopenia in Asian Chinese men and women

Abstract

Objectives: Our aim was to investigate the prevalence and predictive variables of sarcopenia.

Methods: We recruited participants from the Peking Union Medical College Hospital Multicenter Prospective Longitudinal Sarcopenia Study (PPLSS). Muscle mass was quantified using bioimpedance, and muscle function was quantified using grip strength and gait speed. Logistic regression revealed the relationships between sarcopenia and nutritional, lifestyle, disease, psychosocial and physical variables.

Results: The prevalence of sarcopenia and sarcopenic obesity was 9.2%-16.2% and 0.26%-9.1%, respectively. Old age, single status, undernourishment, higher income, smoking, low physical activity, poor appetite and low protein diets were significantly associated with sarcopenia. Multiple logistic regression analysis showed that age was a risk factor for all stages of sarcopenia, and participants above 80 years were greater than fivefold more susceptible to sarcopenia, while lower physical activity was an independent risk factor. The optimal cut-off value for age was 71 years, which departs from the commonly accepted cut-off of 60 years. Female participants were greater than twofold less susceptible to sarcopenia than male participants. The sterol derivative 25-hydroxyvitamin D was associated with fourfold lower odds of sarcopenia in male participants. Several protein intake variables were also correlated with sarcopenia. Based on these parameters, we defined a highly predictive index for sarcopenia.

Conclusions: Our findings support a predictive index of sarcopenia, which agglomerates the complex influences that sterol metabolism and nutrition exert on male vs female participants.

Keywords: BMI; hand grip strength; predictive model; sarcopenia; testosterone; vitamin D.

FIGURE 1

Flow chart of participants in the study. Samples for this study were enrolled from the Peking Union Medical College Hospital (PUMCH) Multicenter Prospective Longitudinal Sarcopenia Study (PPLSS). All samples selected were based on the relevant inclusion and exclusion criteria at every step

FIGURE 2

Testosterone levels and muscle parameters in men. Histogram of the testosterone levels in different age groups of male participants. Correlation r is adjusted for age and BMI

FIGURE 3

Correlation between serum 25‐hydroxyvitamin D and muscle parameters. Correlation r is adjusted for age, gender and BMI. A, Serum levels of 25‐hydroxyvitamin D in sarcopenic and non‐sarcopenic subjects. B, Prevalence of sarcopenia based on the levels of serum 25‐hydroxyvitamin D and the dietary reference intake for vitamin D. C, Correlation between serum 25‐hydroxyvitamin D and hand grip strength in men. D, Correlation between serum 25‐hydroxyvitamin D and muscle mass in men. E, Correlation between serum 25‐hydroxyvitamin D and hand grip strength in women. F, Correlation between serum 25‐hydroxyvitamin D and muscle mass in women

FIGURE 4

Distribution of important dietary parameters for elderly men and women. Histograms of the dietary parameters statistically significant for men and women

FIGURE 5

Correlations between body composition parameters and muscle parameters. Correlation r is adjusted for age and gender. BMI, body mass index; RSMMI, relative skeletal muscle mass index

FIGURE 6

Receiver operating characteristic (ROC) curve analyses of various anthropometric indicators for sarcopenia, based on the AWGS definition. ROC curves are shown for (A) males ≥ 60 years, (B) males 60‐69 years, (C) males 70‐79 years, (D) males ≥ 80 years, (E) females ≥ 60 years, (F) females 60‐69 years, (G) females 70‐79 years, (H) females ≥ 80 years. AC, abdominal circumference; AWGS, Asian Working Group for Sarcopenia; BMI, body mass index; CC, calf circumference; HG, hand grip; MAC, mid‐upper arm circumference