Is waist circumference a negative predictor of calcaneal bone mineral density in adult Chinese men with normal weight?

Background: Our study aimed to evaluate the association between waist circumference (WC) and calcaneal bone mineral density (BMD) in adult Chinese men with normal weight.

Methods: This was a cross-sectional study. A total of 4,663 male participants aged 40 years or older residing in Ningde and Wuyishan, two cities locating in Fujian province of China, were randomly recruited between 2011 and 2012. Each participant should complete a standard questionnaire, undergo anthropometric and calcaneus quantitative ultrasound (QUS) measurements and have blood sample taken. Anthropometric, biochemical and calcaneal QUS parameters of 1,583 male participants with BMI ranging from 18.5 to 22.9 were included in the analysis. WC was divided into quartiles (Q1-Q4: <71, 71-75, 75-78, >78 cm). The relationship between WC (quartiles) and BMD was analyzed by multiple linear regression models.

Results: Mean age of the whole population was 54.6±9.8 years. Anthropometric and biochemical parameters were almost normal. Multiple linear regression analysis showed that BMD was negatively associated with increasing WC quartiles except for Q2 after adjusting for age and BMI, and this relationship remained negative except for Q2 when further adjustment was made for other covariates. Multiple logistic regression model also showed that the risks of osteopenia and osteoporosis increased across WC quartiles.

Conclusions: The present study indicated that WC was a negative predictor of calcaneal BMD in adult Chinese men with normal weight. It suggests that, even for the normal-weight Asian males, monitoring accrual of abdominal adipose is still helpful for the purpose of preventing bone loss.