Relationship Between Biochemical Markers Of Bone Turnover And Pancreatic Islet Function And Retinopathy In Type 2 Diabetic Patients

Objective:To explore the relationships between the biochemical markers of bone turnover and the insulin resistance、insulin secretion and diabetic retinopathy (DR) with type 2 diabetes.Method:We selected 137 hospital patients in SUBEI hospital with type 2 diabetes (63 men,74 women, age:64.85±10.57 years) and 88 healthy people(42 men,46 women, age:62.30±9.77 years) with heath checkup in our hospital in the same period.25(OH)D、BAP、TRACP-5b were measured by radioimmunoassay and glycosylated hemoglobin (HbAlc)、fasting blood glucose (FPG)、fasting C peptide (FCP)、calcium (Ca), phosphorus (P), serum creatinine (CRE), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) were measured by high-performance liquid chromatography. Recorded of body weight, height. Calculated BMI、HOMA-β、HOMA-CR according to the formula.Result1 Independent samples T test25(OH)D 3 levels were lower in the diabetes mellitus type 2 patients than in the control group, being 43.25±21.09 nmmol/L and 66.43±32.47 nmmol/L, in the patient and control group (p< 0.05). TRACP-5b levels were higher in the diabetes mellitus type 2 patients than in the control group, being 4.70±1.05 U/L and 2.97±1.42 U/L, in the patient and control groups(p < 0.05). BAP levels were lower in the diabetes mellitus type 2 patients than in the control group, being 17.32±8.33 ug/L and 19.54±6.46 ug/L, in the patient and control groups, but the difference had no statistical significance (P>0.05). LnHOMA-β levels were lower in the diabetes mellitus type 2 patients than in the control group, being 4.70±0.70 and 7.86±0.68, in the patient and control groups (P<0.05). HOMA-CR levels were higher in the diabetes mellitus type 2 patients than in the control group, being 19.34±4.30 and 12.08±10.19, in the patient and control groups P<0.05). Patients with T2DM had no statistical significance in Ca (P=0.879)、 P (P=0.667)、CRE (P=0.532)、TG (P=0.473)、HDL-C (P=0.432)、LDL-C (P=0.587)、Age (P=0.156)、BMI (P=0.687) as compared to the control group.2 Correlation analysis25(OH)D levels were found to be positively associated with FCP (r=0.876, P≈ 0.000), LnHOMA-β (r=0.393, P≈0.000)、Ca (r=0.151, P=0.023) and inversely associated with FPG (r=-0.580, P≈0.000)、HBA1c (r=-0.481, P≈0.000)、 BMI (r=- 0.496, P≈ 0.000). BAP levels were found to be positively associated with HBAlc (r=0.149, P=0.025) and inversely associated with HOMA-CR (r=-0.157, P=0.018) TRACP5b levels were found to be positively associated with LnHOMA-P (r=0.161, P=0.016). LnHOMA-P levels were found to be positively associated with FCP (r=0.519, P≈ 0.000) and inversely associated with FPG (r=-0.679, P≈O.000), HBA1c (r=-0.716, P≈ 0.000), BMI (r=-0.222, P=0.001)、Age (r=-0.141, P=0.035). All above T2DM patient and control groups were analysed together.3 Logistic regression analysisTake FCP (X1), LnHOMA-β (X2)、BMI (X3) as the independent variables,25-(OH)D(Y) as dependent variable, the multiple regression equation is established: Y=31.929+19.722X1-1.258X2-0.859X3; Take HOMA-CR (X1)、HbA1c (X2) as the independent variables, BAP as dependent variable, the multiple regression equation is established:Y= 15.611-0.130X1+0.399X2; Take LnHOMA-P (X) as the independent variables, TRACP-5b as dependent variable, the regression equation is established: Y=1.695+0.211X. Take 25-(OH)D (X1)、FPG (X2)、HBA1c(X3) as the independent variables, LnHOMA-β(Y) as dependent variable, the multiple regression equation is established: Y=10.491-0.017X1-0.186X2-0.286X3; Take BAP (X) as the independent variables, HOMA-CR as dependent variable, the regression equation is established:Y= 18.195-0.187X.4 Chi-square testThe imorbidity of diabetic retinopathy is different between VDD group and NVDD group. The DR imorbidity of VDD group was higher than NVDD group, being 86.87% and 47.37%. There were significant differences and an ascending trend in prevalence of NDR, NPDR and PDR among deficiency rate of 25-(OH)D. The deficiency rate of 25(OH)D in PDR group was higher than that of NDR and NPDR groups.5 Analysis of varianceThere were significant differences and an descending trend in prevalence of NDR, NPDR and PDR among 25(OH)D 3 levels.25(OH)D 3 levels were lower in the PDR, NPDR group than in the NDR group, being 36.75±11.88 nmmol/L,43.28±15.08 nmmol/L and 54.22±17.67 nmmol/L in the PDR、NPDR and NDR groups (p< 0.05).Conclusion1.25(OH)D 3 levels decreased and TRACP-5b increased in the T2DM patients indicated that compared with those in control group, bone metabolism was abnormal in T2DM patients.2.25-(OH) D levels is associated with Islet function.3. The 25(OH)D levels had a relationship with the severity of Diabetic retinopathy, indicated that 25(OH)D levels is associated with the development of type 2 diabetes patients.