Prevalence of osteoporosis by educational level in a cohort of postmenopausal women.

To evaluate whether the prevalence of osteoporosis and related risk factors might be influenced by the level of education, as has been demonstrated for many other chronic diseases, 6160 postmenopausal women at their first densitometric referral were interviewed about reproductive variables, past and current use of estrogens, prevalence of chronic diseases, and lifestyle factors such as calcium intake, physical activity, smoking and overweight. This sample was stratified by years of formal education. Densitometric evaluation was performed by dual-energy X-ray absorptiometry. Age at menarche, past exposure to oral contraceptives, use of hormone replacement therapy, prevalence of chronic diseases, physical activity, overweight and smoking showed significant trends according to the years of education. The prevalence of osteoporosis showed an inverse relationship with level of education, ranging from 18.3% for the most educated to 27.8% for the least educated women. Multiple logistic regression analysis demonstrated a predictive role toward osteoporosis by age, age at menarche and menopause, hormone replacement therapy, calcium intake, physical activity and body mass index. Using the lowest educational level as reference category, increases in educational status were associated with a significantly reduced risk for osteoporosis (OR = 0.76, 95% CI 0.65-0.90 for 6-8 years of schooling; OR = 0.68, 95% CI 0.57-0.82 for 9 years or more). This study shows differences in the prevalence of osteoporosis among educational classes and the protective role played by increases in formal education. If these results are confirmed in other population studies, public health intervention programs will have to consider the socioeconomic and cultural background of the population strata that run a greater risk of osteoporosis.