Baseline serum total adiponectin level is positively associated with changes in bone mineral density after 1-year treatment of type 2 diabetes mellitus

Although recent clinical studies have shown that serum adiponectin level was negatively associated with bone mineral density (BMD), serum adiponectin action on bone metabolism in humans is still unclear. We investigated the relationships between serum levels of total and high-molecular weight (HMW) adiponectin and its ratio (HMW-total ratio) vs chronological changes in BMD at the lumbar spine, femoral neck (FN), and one third of the radius after 1-year treatment of type 2 diabetes mellitus in 32 Japanese patients. Serum total adiponectin, but not HMW adiponectin or HMW-total ratio, was significantly and positively correlated with percentage change in FN-BMD (r = 0.35, P < .05). Multiple regression analysis adjusted for age, duration of diabetes, sex, body height, body weight, waist circumference, serum creatinine, and hemoglobin A_1c showed that serum total adiponectin was still significantly and positively correlated with percentage change in FN-BMD (r = 0.65, P < .01). On the other hand, no significant relationships were found between serum levels of hemoglobin A_1c, pentosidine, bone formation markers (bone-specific alkaline phosphatase and osteocalcin), or a bone resorption marker (urinary N-terminal cross-linked telopeptide of type-I collagen) vs percentage change in BMD at any site. These findings suggest that serum total adiponectin could be clinically useful for predicting BMD change during treatment of type 2 diabetes mellitus. Adiponectin might protect against BMD reduction in patients with type 2 diabetes mellitus.