Protective role of serum uric acid for bone loss in postmenopausal women

Abstract

Researchers had found that there is an association between oxidative stress and osteoporosis. Postmenopausal osteoporosis causes major public health problems. Since Uric acid has strong antioxidant properties, it will improve bone quality. This cross-sectional observational study was done to determine the association of Uric Acid and Bone Mineral Density of 75 healthy postmenopausal women who came for a master health checkup. The mean age was 60.5 years. After ethical clearance and informed consent, women were recruited for the study at Saveetha Medical Hospital Chennai. Women with medical conditions or who were using drugs affecting bone metabolism or uric acid were excluded. Basic investigations were Hb, serum UA, blood urea, serum creatinine, serum calcium and alkaline phosphatase, blood glucose and glycosylated Hb. Total Cholesterol, HDL, LDL, VLDL, 25 hydroxy Vitamin D were also done. Serum UA levels were graded as <3.9, 3.9–4.9, 5–6.1, and ≥6.2 mg/dl. Bone Mineral Density (BMD) was calculated with Dual Energy X-ray Absorptiometer (DXA). Osteoporosis was defined as BMD T-score −2.5 and below. BMD with a T-score of -1 −2.5 was classified as osteopenia (WHO). In women with high UA, there were significantly higher levels of low-density lipoprotein, and calcium, as compared to women with low UA group (p<0.05). High UA group, as compared to the low UA group, also had lower levels of high-density lipoprotein (p<0.001). Women with higher Uric acid levels had lower BMI, lesser years of duration of Menopause and increased BMD. Serum UA level had a positive correlation with the Lumbar BMD T score and Right Femoral Neck BMD T Score. In UA >5.4mg/dl group Osteoporosis was nil.