[Analysis of prevalence and related factors of osteoporosis in retired population based on Dongfeng-Tongji Cohort].

Objective: To investigate the prevalence and related factors of osteoporosis among retired population in Dongfeng-Tongji cohort. Methods: 27 009 retired participants were recruited from Dongfeng Motor Corporation in Hubei Province in 2008 and followed up from April to October in 2013. newly retired participants also were recruited. Data were collected by using questionnaire, physical examination, serum hepatase detection and bone densitometry. Totally, 30 916 participants were included for data analysis after excluding participants with severe bone metabolic diseases, taking hormone drugs, incomplete follow-up data and who were under 45 years old. Age-standardized prevalence of osteoporosis was calculated according to data of the 2010 Sixth National Population Census. Multivariate logistic regression analysis was applied to explore the associated factors of osteoporosis. Results: Prevalence of osteoporosis was 42.3% (13 083/30 916) and age standardized prevalence was 40.7%: 35.0% (4 854/13 878) and 34.8% for males; 48.3% (8 229/17 038) and 47.1% for females. Significantly associated factors with osteoporosis for both males and females included: older age (male: OR=1.67, 95%CI: 1.40-1.99; female:OR=3.34, 95%CI: 2.70-4.13), lower BMI (male: OR=1.70, 95%CI: 1.40-2.06; female: OR=1.27, 95%CI: 1.04-1.53), exercise (male: OR=0.69, 95%CI: 0.61-0.78; female: OR=0.87, 95%CI: 0.80-0.96), abnormal elevated serum alkaline phosphatase (ALP) (male: OR=1.12, 95%CI: 1.01-1.24; female: OR=1.15, 95%CI: 1.06-1.25), γ-glutamyltransferase (γ-GT) (male: OR=1.16, 95%CI: 1.02-1.30; female: OR=1.13, 95%CI: 1.03-1.24) and aspartate transaminase/alanine aminotransferase (AST/ALT) (male: OR=1.15, 95%CI: 1.05-1.25; female: OR=1.28, 95%CI: 1.19-1.38). Smoking (OR=1.27, 95%CI: 1.07-1.39) and drinking (OR=1.11, 95%CI: 1.08-1.16) were associated factors for males while menopausal (OR=1.67, 95%CI: 1.47-1.89) for females. There were positive dose-response correlation relationships of serum levels of ALP, γ-GT and AST/ALT with osteoporosis (all P values<0.05). Conclusion: Osteoporosis was relatively common among retired population in Dongfeng-Tongji cohort. In addition to known factors such as older age, lower BMI and exercise, abnormal elevated serum ALP, γ-GT and AST/ALT were also associated with osteoporosis.