Study On The Correlation Between Vitamin D Level And Metabolic Index And Chronic Complications In Patients With Type 2 Diabetes Mellitus

Objective: To determine the level of serum vitamin D(VD)in patients with type 2 diabetes mellitus(T2DM).To explore the correlation between VD and metabolic index and chronic complications in patients with T2 DM,and to further explore the possible influencing factors of VD deficiency or insufficiency in diabetic patients.Methods:1.In this study,115 patients with T2 DM admitted to the endocrinology department of the affiliated hospital of north Sichuan medical college from April to October 2018 were selected as the observation group,including 53 males and 62 females,with an average age(64.42±10.98 years)and an average course of disease(12.26±7.53 years).In addition,81 subjects who underwent physical examination in our hospital during the same period were randomly selected as the normal control group,including 34 males and 47 females,with an average age(64.21±9.02 years).All subjects signed the informed consent.2.Serum 25(OH)D level of all subjects was determined by chemical immunization method.And their height,weight,systolic blood pressure(SBP),Diastolic blood pressure(DBP),fasting blood glucose(FPG),glycated hemoglobin(HbAlc),fasting insulin(INS),aspartate aminotransferase(AST),alanine aminotransferase(ALT),Blood urea nitrogen(BUN),creatinine(Cr),Urinary Albumin creatinine ratio(UACR),Blood uric acid(UA),glycerol Triglyceride(TG),Cholesterol(TC),High Density Lipoprotein Cholesterol(HDL-C),Low Density Lipoprotein Cholesterol(LDL-C),blood calcium,phosphorus and high-sensitivity C-reactive protein(hs-CRP),etc.body mass index(BMI)was calculated.Calculating insulin resistance index(HOMA-IR)and islet beta-cell function(HOMA-?)by Homeostasis model.The eGFR was calculated by simplified MDRD formula.3.According to the 2011 American endocrine society definition standard of VD level the normal range,the patients were divided into two groups according to the serum levels of 25(OH)D: VD deficiency/insufficiency group(25(OH)D <30 ng/mL)and VD normal group(25(OH)D?30 ng/mL).The general information,metabolic index,and chronic complications were analyzed between the two groups,and the influencing factors of VD deficiency/insufficiency in T2 DM patients was analyzed.4.SPSS 20.0 statistical analysis software was used to analyze all the data,and the results were expressed as mean soil standard deviation((?)±s).The measurement data were tested by t-test and the numeration data were tested by Chi-square tests.Pearson correlation analysis was used for correlation analysis Logistic regression was used to analyze the main influencing factors of VD deficiency/ insufficiency in T2 DM patients.P< 0.05 was considered statistically significant.Results:1.The VD level in the T2 DM group was significantly lower than that in the control group,and the average serum concentrations of 25(OH)D were(30.09±17.32)ng/ml and(62.97±21.48)ng/ml(P<0.05);Both the T2 DM group and the control group showed lower VD level in females than males(P<0.05);Compared with the control group,BMI,SBP,FPG,HbAlc,TG,TC and LDL-C were increased,while HDL-C was decreased inte T2 DM group(P<0.05).2.Compared with the VD deficiency/insufficiency group and the VD normal group,there were statistically significant differences in gender,the use of insulin,BMI,HbAlc,TG and LDL-C between the two groups(P<0.05);The proportion of women in the VD deficiency/insufficiency group was higher than that in VD normal group(P<0.05);The proportion of the using insulin was higher in the VD normal group(P<0.05);BMI,HbAlc,TG and LDL-C in the VD deficiency/insufficiency group were higher than those in the VD normal group(P <0.05).3.Correlation analysis showed that 25(OH)D was negatively correlated with BMI,HbAlc,TG and LDL-C(r=-0.332,-0.285,-0.292,-0.309,P<0.05).4.The prevalence of diabetic nephropathy,diabetic retinopathy and diabetic peripheral neuropathy were higher in the VD deficiency/deficiency group than in the VD normal group,and the prevalence of these three complications were respectively(44.6%vs24.4%)?(45.9%vs24.4%)?(56.8%vs36.6%)(P<0.05).5.Logistic regression analysis showed that HbAlc and LDL-C were risk factors of VD deficiency/ insufficiency in the T2 DM patients(OR=1.212,3.803,P<0.05).Using insulin was a protective factors of VD deficiency/ insufficiency in T2 DM patients(OR=0.099,P<0.05).Conclusions: The level of VD in T2 DM patients is generally lower than healthy people,and the lack of VD in female patients is more serious than male patients.The deficiency/ insufficiency of VD in T2 DM patients will affect the disorder of glucose and lipid metabolism,increase the morbidity of chronic complications such as diabetic nephropathy,diabetic retinopathy and diabetic peripheral neuropathy.Poor control of glucose,dyslipidemia and may also aggravate VD deficiency.Using insulin may help improve VD level.This study shows that serum VD level may be correlated with glucose and lipid metabolism and chronic complications in T2 DM patients.However,whether improving VD deficiency/deficiency status in T2 DM patients can better control blood glucose and lipid levels and prevent or delay the occurrence of chronic complications remains to be further studied.