Relationship of serum vitamin D levels with diabetic microvascular complications in patients with type 2 diabetes mellitus / 中华医学杂志(英文版)

BACKGROUND@#Vitamin D deficiency has been reported to be associated with diabetic microvascular complications, but previous studies have only focused on the relationship between vitamin D and specific complications. Therefore, we aimed to explore the relationship between vitamin D level and diabetic microvascular complications in general, including diabetic retinopathy (DR), diabetic nephropathy (DN), and diabetic peripheral neuropathy (DPN).@*METHODS@#This was a cross-sectional study of 815 patients with type 2 diabetes mellitus (T2DM). Clinical information and laboratory results were collected from the medical records. The relationship between vitamin D and the three diabetic microvascular complications was investigated.@*RESULTS@#The serum 25-hydroxyvitamin D (25 [OH] D) level of patients with DPN and/or DN was significantly lower than that of T2DM patients without any microvascular complications (P < 0.01). Univariate analysis showed that the 25 (OH) D level was related to DPN and DN, but not DR. After adjustment, the 25 (OH) D level was confirmed to be an independent protective factor for DPN (odds ratio [OR]: 0.968, P = 0.004]) and DN (OR: 0.962, P = 0.006). The prevalence of DPN and DN increased significantly as the serum 25 (OH) D levels decreased. Furthermore, patients with both DPN and DN had the lowest concentration of serum 25 (OH) D (P < 0.001), and the prevalence of macroalbuminuria increased more abruptly than that of microalbuminuria across the 25 (OH) D tertiles. Among the patients with vitamin D insufficiency, those with DPN presented more comorbid macroalbuminuria than those without DPN (15.32% vs. 4.91%; P = 0.001).@*CONCLUSIONS@#Vitamin D deficiency is independently associated with higher risk of DPN and DN, but not DR, in T2DM patients. Further, it may be a potential predictor for both the occurrence and severity of DPN and DN.

Relationship between SLC12A3 gene Arg913Gln polymorphism and type 2 diabetic nephropathy in Han population of Shanghai / 上海第二医科大学学报

Objective To explore the relationship between Arg913Gln(G→A) polymorphism of solute carrier family 12 member 3 (SLC12A3) gene and diabetic nephropathy (DN) in type 2 diabetes mellitus (T2DM) in Han population of Shanghai. Methods Two hundred and fifty-eight Han ethnic people in Shanghai with T2DM (T2DM group) were divided into non-DN group (DN0 group, n=95) and DN group (n=163) according to 24 h urine albumin excretion rate (AER), and those in DN group were subdivided into microalbuminuria group (DN1 group, n=95) and macroalbuminuria group (DN2 group, n=68). Besides, 82 people with normal results of oral glucose tolerance test (OGTT), without diabetes mellitus and nephropathy were served as controls. PCR-sequencing was used to detect the genotypes of Arg913Gln polymorphism of SLC12A3 gene. Genotypic and allelic frequencies and clinical characteristics were compared among groups. Results Three genotypes (GG, GA and AA) were detected. The frequencies of GA+AA genotype and A allele in T2DM group were higher than those in control group, while there was no significant difference between groups (P>0.05). There was no significant difference in genotypic or allelic frequencies among subgroups of T2DM group (P>0.05). The level of triglyeeride (TG), AER, level of fasting insulin (FINS) and HOMA-IR in patients with GA+AA genotype were significantly higher than those in patients with GG genotype in T2DM group (P<0.05). Conclusion Arg913Gln(G→A) polymorphism of SLC12A3 gene is not significantly associated with T2DM and DN in Han population of Shanghai. The AER of people with GA+AA genotype is significantly higher than that with GG genotype. Arg913Gln (G→A) polymorphism of SLC12A3 gene may predict the risk of increase of albuminuria in patients with T2DM in Han population of Shanghai.