Bone turnover markers, glucose and lipid metabolism in relation to atherosclerosis in type-2 diabetic patients: a longitudinal study

Abstract

Background: Bone metabolism is affected by risk factors of atherosclerosis and hyperglycemia induced low bone turnover with osteoblastic dysfunction. Limited information is available on the relationship between bone turnover markers (BTMs) and atherosclerosis or its related risk factors in patients with Type-2 diabetes mellitus (T2DM). Methods: A total of 135 patients (men=62; women=73) (age≥50 years) with poorly controlled T2DM [indicated by haemoglobin-A1c (HbA1c)] were followed-up over 12 months during glycemic control evaluation. Each patient (at baseline and visits on 3, 6, 9 and 12 months) provided fasting blood sample and second-void morning urine samples for the measurements of BTMs [serum osteocalcin (s-OC), bone alkaline phosphatase (s-bone ALP), procollagen type 1 Nterminal propeptide (s-PINP), crosslinked C-terminal telopeptide of type 1 collagen (sCTX), tartarate-resistance acid phosphatase isoform 5b (s-TRACP-5b) and urinary Ntelopeptide of type 1 collagen (u-NTX)]. Various hormones, HbA1c; lipids, glucose and creatinine were measured. Bone mineral density was determined at baseline visit and at 12-month visit. Also, the plaque score (PS) was calculated. Results: Multiple regression analysis showed that changes in s-OC were negatively correlated with HbA1c (r=-0.46, Pb0.001). Baseline s-OC levels were negatively correlated with changes in triglyceride levels (r=-0.37, Pb0.001) and positively with high-density lipoprotein-cholesterol (HDL-c) (r=0.44, Pb0.001). Changes in s-OC correlated positively with baseline PS (r=0.49, Pb0.001) and negatively with changes in PS (r=-0.41, Pb0.001) independent of other potential atherosclerosis risk factors. Conclusions: Association between s-OC with glucose, lipid metabolic indicators and PS independently of other atherosclerosis-related risk factors in patients with T2DM. This article is part of a Special Issue entitled ECTS 2012. Disclosure of interest: None Declared. doi:10.1016/j.bone.2012.02.442 PP254 Volumetric bone mineral density (vbmd) at tibia site and vitamin d status in premenopausal south asian and caucasian women O.A. Hakim⁎, A. Darling, K. Hart, J.L. Berry, S. Lanham-New Nutrition, University of Surrey, Guildford, UK Vitamin D Research Group, University of Manchester, Manchester, UK Abstract: Recent studies indicate thatwomenof European origin have higher areal bone mineral density (BMD) than South Asianwomen. However this has been explained by ethnic variation in bone size [1]. Few data exist on true volumetric BMD in premenopausal South Asianwomen and nodata is available at the tibia site. As part of theD-FINES (VitaminD, Food Intake,Nutrition andExposure to Sunlight in SouthernEngland) study,which investigates the interaction betweendiet and sunlight exposure and vitaminD status,we aimed to investigate differences in volumetric bone mineral density (vBMD) between South Asian (SA) and Caucasian (C)womenat the tibia and determine if there is an association betweenvBMDand serum 25(OH)D. Thirty five healthy premenopausal women (21 C and 14 SA), age ranges 1855 yrs, were scanned by peripheral Quantitative Computed Tomography (pQCT) at the tibia (non-dominant) using a Stratec XCT 2000 pQCT machine. Fasted blood samples were Recent studies indicate thatwomenof European origin have higher areal bone mineral density (BMD) than South Asianwomen. However this has been explained by ethnic variation in bone size [1]. Few data exist on true volumetric BMD in premenopausal South Asianwomen and nodata is available at the tibia site. As part of theD-FINES (VitaminD, Food Intake,Nutrition andExposure to Sunlight in SouthernEngland) study,which investigates the interaction betweendiet and sunlight exposure and vitaminD status,we aimed to investigate differences in volumetric bone mineral density (vBMD) between South Asian (SA) and Caucasian (C)womenat the tibia and determine if there is an association betweenvBMDand serum 25(OH)D. Thirty five healthy premenopausal women (21 C and 14 SA), age ranges 1855 yrs, were scanned by peripheral Quantitative Computed Tomography (pQCT) at the tibia (non-dominant) using a Stratec XCT 2000 pQCT machine. Fasted blood samples were collected for vitamin D analysis. SA women were significantly shorter (pb0.001), and slightly heavier than C women; Therefore SA had significantly higher BMI (pb0.05) than C women. SA women had significantly lower 25(OH)D concentration than C women (pb0.001) with mean values of 31.53[16.32] and 80.91[20.08] (nmol/l) respectively. SA women had significantly smaller bone size and higher vBMD than C women (pb0.05) for total, trabecular, and cortical bone at the 4% site. SA women had significantly lower total vBMD at 14% site (pb0.05) and the 38% site (pb0.01) than Caucasians. SA had significantly lower cortical density at site 14% than Caucasians (pb0.05).This was also lower at the 38% site but this was not statistically significant. There was a trend for a negative association between 25(OH)D and total area, trabecular area, and cortical area at the 4% site in the Asian group only (p=0.06). There was no correlation between 25(OH)D and vBMD at any site in either ethnic group. Our finding of differences in vBMD at the tibia for SA and C premenopausal women is novel and now requires further investigation. This article is part of a Special Issue entitled ECTS 2012. Disclosure of interest: None Declared.