The Associations between Bone Mineral Density and Oxidative Stress Biomarkers in Postmenopausal Women.

ABSTRACT

BACKGROUND: Oxidative stress plays an essential role in bone health among postmenopausal women. This study aimed to compare the oxidative stress biomarkers among postmenopausal women aged 50-65 years with normal bone mineral density, osteopenia, and osteoporosis. METHODS: In this observational study, 120 women with normal bone mineral density, 82 with osteopenia, and 86 with osteoporosis were selected based on the densitometry data obtained from the dual-energy X-ray absorptiometry method. The serum total antioxidant capacity (TAC), superoxide dismutase (SOD) activity, and malondialdehyde (MDA) levels were measured using biochemical methods. A binary logistic regression model adjusted for confounders was used to estimate the risk of osteopenia and osteoporosis. The P-value of <0.05 was considered statistically significant. RESULTS: There were significant differences between the three groups in age, menopausal age, body mass index, and education (P<0.05). According to the binary logistic regression model, higher SOD activity and serum TAC levels were associated with a lower risk of osteoporosis (adjusted odds ratio [aOR], 0.991; 95% confidence intervals [CI], 0.986 to 0.996; and aOR, 0.373; 95% CI, 0.141 to 0.986, respectively). MDA was a significant risk factor for osteopenia in postmenopausal women (aOR, 1.702; 95% CI, 1.125 to 2.576). CONCLUSION: Higher SOD activity and serum TAC levels in the studied postmenopausal women were associated with a significantly lower risk of osteoporosis. Moreover, the risk of osteopenia increased significantly with higher serum MDA levels.