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 and 287 +/- 41.4 mg/dl] and PTH [49 +/- 9.87 and 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 and 8.79 +/- 0.7 mg/dl], and 25 OH-D [50.9 +/- 12.6, 45.4 +/- 18.9 micro g/l] and osteocalcin [4.09 +/- 1.48 and 1.89 +/- 0.24 ng/ml] than controls [9.96 +/- 1.9l, 57.9 +/- 13.6 micro g/l, 6.5 +/- 1.5 ng/ml respectively], Urinary calcium and urinary Dpd were higher [270.66 +/- 41.7 and 300.56 +/- 55.67 mg/d and 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 and 0.294], urinary calcium [r=0.340 and 0.260] and Dpd [r=0.468 and 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