Study On Correlation Between 25-hydroxy Vitamin D3 Level And Metabolic Syndrome In Patients With Type 2 Diabetes Mellitus In Shenzhen

BackgroundDiabetes is one of the most common and severe chronic diseases.China has a significant number of diabetes patients in the world.Metabolic syndrome and vitamin D deficiency have received clinical attention.The prevalence of Metabolic syndrome（Met S）in patients with Type 2 diabetes mellitu（T2DM）is significantly higher than in the general population.The causal relationship and correlation between them are still not completely clear.ObjectiveTo investigate the influencing factors of T2DM patients complicated with Met S in Shenzhen,and to explore the correlation between 25-hydroxy vitamin D₃ level and T2DM complicated with Met S and related indexes.MethodsOne thousand two hundred two inpatients admitted to the Department of Endocrinology of Shenzhen Second People’s Hospital from January to December 2020were selected,and 592 patients with T2DM were selected according to the inclusion and exclusion criteria.According to the diagnostic criteria of Met S,the patients were divided into the Met S group and the non-Met S group.They were divided into VD sufficient group,VD insufficient group,and VD deficient group according to the 25-hydroxy vitamin D₃.The differences in clinical indicators in each group were compared.Lasso regression was used to analyze the influencing factors of Met S in T2DM.Spearman correlation was used to analyze the correlation between 25-hydroxy vitamin D₃ and Met S and diabetic vascular complications in T2DM.Smooth curve fitting and threshold effect analysis were performed for the relationship between 25-hydroxyvitamin D₃ and Met S.Results1.Among 592 patients,71.11%（n=421）were male,28.89%（n=171）were female,67.23%（n=398）were Met S,16.89%（n=100）were diabetic macrovascular disease.The prevalence of diabetic macrovascular disease was 73.31%（n=434）,the median age was54.00（47.00-61.00）years old,the median body mass index was 24.95（22.62-27.05）kg/m²,and the median waist-to-hip ratio was 0.94（0.90-0.98）.The median glycated hemoglobin was 8.75（7.10-11.00）%,the median 25-hydroxy vitamin D₃ was 24.89（20.22-30.10）ng/ml,the insufficient/deficient vitamin D rate was 74.83%,the non-standard blood glucose rate was 80.57%,and the non-standard blood lipid rate was81.93%.The rate of body mass index not meeting the standard was 59.97%.2.Compared with the non-Mets group（n=194）,the proportion of males,the proportion of hypertension,body mass index,waistline,hipline,waist-to-hip ratio,fasting blood glucose,triglyceride,homocysteine,24-hour urinary albumin,serum creatinine,and serum uric acid were significantly increased in the Met S group（n=398）.The levels of 25hydroxy vitamin D₃ and high density lipoprotein cholesterol were significantly reduced.3.592 patients with T2DM were randomly divided into two unequal groups:training set（n=429）and validation set（n=163）at 75%and 25%,respectively.Lasso regression combined with multivariate Logistic regression analysis showed that:coronary heart disease,cerebrovascular disease,stenosis or occlusion of the neck or lower limb arteries,age,duration of diabetes,body mass index,waist-to-hip ratio,fasting blood glucose,triglyceride,low density lipoprotein cholesterol and serum uric acid were risk factors for T2DM with Met S.25-hydroxy vitamin D₃ and high density lipoprotein cholesterol are protective factors of T2DM complicated with Met S.The nomogram prediction model was established,and the AUC of the training set and validation set for predicting the risk of T2DM combined with Met S was 0.899（95%CI 0.870～0.929）and 0.926（95%CI0.886～0.967）,respectively.DCA showed that in the training set and validation set,when the threshold probability was>0.06 and>0.04,respectively,the net benefit of predicting the risk of T2DM combined with Met S was higher.4.Spearman correlation conducted a correlation analysis between the continuous variables in 25-hydroxy vitamin D₃ and diabetes-related index;the results showed that25-hydroxy vitamin D₃ level and Met S,fasting blood glucose,triglyceride,low density lipoprotein cholesterol and 24-hour urinary albumin levels showed a negative correlation.Conclusion1.The prevalence of Met S is high in hospitalized patients with T2DM in this study,and the proportion of diabetic microvascular complications is high.There is apparent vitamin D insufficiency/deficiency.2.The vitamin D level in T2DM patients with Met S is lower,and blood glucose and lipid control are worse.Vitamin D is a protective factor for T2DM complicated with Met S.3.The rate of blood glucose compliance in T2DM patients with vitamin D insufficiency/deficiency is lower,and the number of Met S components is more.There was a negative linear correlation between vitamin D and Met S.As vitamin D level increased,the risk of developing Met S decreased.