Association between basal metabolic function and bone metabolism in postmenopausal women with type 2 diabetes

• Basal metabolic rate and bone metabolism were evaluated in postmenopausal women with type 2 diabetes.
• Bone metabolism was associated with resting energy expenditure.
• Serum vitamin D was associated with respiratory quotient and insulin requirement.

ObjectiveDiabetes is a risk factor for osteoporosis, and glycemic control is critical during osteoporosis treatment in patients with type 2 diabetes (T2D). However, diabetic therapies have potentially adverse effects on bone metabolism. Additionally, biomarkers for bone metabolism are directly affected by drug therapies for osteoporosis. This study examined resting energy expenditure (REE) and respiratory quotient (RQ) as indices of bone metabolism in postmenopausal Japanese women with T2D.MethodsForty-six postmenopausal Japanese women with T2D were examined. Procollagen type 1 N-terminal propeptide (P1NP, a fasting serum bone formation marker) and carboxy-terminal collagen cross-links-1 (CTX-1, a resorption marker) were evaluated, along with intact parathyroid hormone, 25-hydroxyvitamin D (25[OH]D), urine microalbumin, motor nerve conduction velocity, sensory nerve conduction velocity, R-R interval, body composition, REE, RQ, and bone mineral density at the nondominant distal radius.ResultsThe mean T-score was low with high variance (−1.7 ± 1.6), and 18 patients (39%) met the criteria for osteoporosis. REE was positively correlated with body mass index (β = 0.517; r2 = 0.250), serum calcium (β = 0.624; r2 = 0.200), glycated hemoglobin A1C for the previous 6 mo (β = 0.395; r2 = 0.137), and the serum P1NP/CTX-1 ratio (β = 0.380; r2 = 0.144). RQ was positively correlated with serum 25(OH)D (β = 0.387; r2 = 0.131).ConclusionThe basal metabolic rate and diabetic pathophysiology are interrelated with bone turnover.