ABSTRACT
Objective:
To investigate the association between body mass index (BMI) and bone mineral density (BMD) in postmenopausal women.
Methods:
Observational study with postmenopausal women who underwent bone densitometry in Palmeira das Missões - RS. Sociodemographic data, risk for osteoporosis and food intake were assessed through a specific form. BMI was calculated according to WHO criteria. The assessment of BMD was performed by dual-energy X-ray absorptiometry (DXA) and classified according to WHO. Statistical analysis was performed using prevalence ratios (PR) and their respective 95% confidence intervals for the factors studied. Variables associated with p < 0.20 with the different outcomes (osteopenia and osteoporosis) were included in a Poisson regression model with robust variance to adjust for potential confounding factors. A 5% significance level was considered.
Results:
393 postmenopausal women with a mean age of 59.6 ± 8.2 years participated.After the adjustments, the normal weight women had 1.2 times the prevalence of osteopenia of obese women (PR = 1.2; CI 95% 1.3-1.5). Considering osteoporosis, the PR of euthophic women was twice the PR of obese women (PR = 2; CI 95% 1.4-2.9) and was 1.7 times greater for overweight group compared to obese category (PR = 1.7; CI 95% 1.2-2.5).
Conclusion:
Obese women had lower prevalence of osteopenia compared with normal weight subjects and also with lower prevalence of osteoporosis as compared to normal- and overweight women.
Keywords:
Osteoporosis; Body mass index; Women; Bone mineral density