Altered Bone Metabolic Markers In Type 2 Diabetes Mellitus: Impact of Glycemic Control

Abstract

To study the influence of glycemic control on bone minerals and biochemical markers of bone metabolism in patients with type 2 diabetes mellitus. A Case-control study was conducted at Uhod Hospital, KSA from October 2003 to August 2004 to study 60 premenopausal, multipareous female patients with type 2 diabetes mellitus for >5 years, under oral anti-diabetics, with no diabetic complications. They were divided according to their glycemic control into: controlled group (n=22) and poorly controlled group (n=38) and were compared to 30 age matched healthy women. Osteocalcin (OC), urinary deoxypyridinoline (Dpd), Parathyroid hormone (PTH) were measured by chemiluminescent enzyme immunometric assay and 25 hydroxy vitamin D (25 OH-D) was measured by high performance liquid chromatography. In both diabetic groups, there were higher ALP (177± 39.88 & 287 ± 41.4 mg/dl) and PTH (49 ±9.87 & 56.25± 12.3 Pg/ml) than in controls (144 ± 22.54 mg/dl, 26.9± 5.60 Pg/ml respectively), but lower serum calcium (8.87± 0.3 & 8.79 ±0.7 mg/dl), and 25 OH-D (50.9±12.6, 45.4±18.9 μg/l) and osteocalcin (4.09 ± 1.48 & 1.89 ± 0.24 ng/ml) than controls (9.96± 1.9l, 57.9±13.6 μg/l, 6.5±1.5 ng/ml respectively), Urinary calcium and urinary Dpd were higher (270.66±41.7 & 300.56 ± 55.67 mg/d & 10.8 ± 4.6, 12.06±5.12 nM/mM creatinine) than in controls (244.23 ±51.5 mg/d, 6.2 ±0.8 nM/mM creatinine). Glycemic indices (FBG, HbA1C) showed significant positive correlation with ALP (r=0.290 & 0.294), urinary calcium (r=0.340 & 0.260) and Dpd (r=0.468 & 0.228). Our data give evidence of altered bone metabolic markers in both controlled and uncontrolled female patients with type 2 diabetes mellitus with more significant alterations in the uncontrolled group. This could reflect the strong impact of glycemic control on diabetic bone turnover.