Lipid profiles as potential mediators linking body mass index to osteoporosis among Chinese adults: the Henan Rural Cohort Study.

ABSTRACT

This study is to examine the relationship between body mass index (BMI) and osteoporosis in rural areas of China, and then explore whether this association was mediated by lipid profiles. Results showed that with the increasing of BMI, the risk of osteoporosis was reduced, and lipid profiles mediate this association. INTRODUCTION: To examine the relationship between BMI and osteoporosis, and explore whether this association was mediated by lipid profiles. METHODS: A total of 8272 participants (18-79 years) were enrolled from the Henan Rural Cohort Study. The bone mineral density of the calcaneus was measured using an ultrasonic bone density apparatus. Logistic regression and restricted cubic splines were used to evaluate the odds ratio (OR) and 95% confidence intervals (95% CI). Mediation analysis using bootstrap was performed to examine the contribution of lipid profiles to BMI-related osteoporosis. RESULTS: The crude and age-standardized prevalence of osteoporosis were 15.93% and 11.77%, respectively. The mean BMIs were 24.12 kg/m2 for participants with osteoporosis and 25.06 kg/m2 for non-osteoporosis participants (P < 0.001). After adjusting for potential confounders, subjects with obesity had a lower OR of osteoporosis (0.493 [95% CI 0.405-0.600], Ptrend < 0.001) compared with normal-weight individuals. Mediation analysis showed that lipid profile partly mediated the relationship between BMI and osteoporosis with indirect effect OR (95% CI) of 0.985 (0.978-0.992), and the proportion explained of BMI was 15.48% for lipid profile. CONCLUSION: With the increasing of BMI, the risk of osteoporosis was reduced in the Chinese adult population, and lipid profiles may be a potential mediator linking reduced risk of osteoporosis. Elucidating the underlying mechanisms will facilitate developing feasible preventive and therapeutic measures for osteoporosis. Chinese clinical trial register ChiCTR-OOC-15006699.