evaluation of 25-hydroxy vitamin d serum levels and thyroidrelated parameters in patients with type 2 diabetes mellitus and healthy people in shiraz, iran

Background and aim: the prevalence of type 2 diabetes mellitus (t2dm) is increasing globally. there is increasing evidence in the correlation between altered vitamin d levels, thyroid dysfunction, and t2dm. the goal of this study was to evaluate the association between serum 25-hydroxy vitamin d (25 (oh) d), lipid profile, glucose and thyroid-related parameters among patients with t2dm and non-diabetic individuals. methods: this case-control study was conducted on 228 individuals (110 type two diabetics and 118 healthy controls). the serum concentration of 25(oh) d was determined by chemiluminescence assay. photometric methods measured serum levels of fasting blood glucose (fbg), calcium, phosphorous, total cholesterol (tc), triacylglyceride (tg), high- density lipoprotein (hdl). low-density lipoprotein (ldl) and vldl levels were estimated from the friedewald equation (ldl-c=tc–hdl-c–(tg/5)). the elisa kit measured serum t4 and tsh. results: 80% of patients with t2dm and 71% of healthy individuals were suffering from vitamin d insufficiency. a non-significant relationship between tg (p=0.36), hdl (p=0.33), vldl (p=0.36), t4 (p=0.56) calcium (p=0.39) and phosphorus (p=0.41) levels were showed in control and diabetic groups. the levels of fbg (p=0.000), tc (p=0.001), ldl (p=0.004), tsh (p=0.000) were significantly higher, and the levels of 25 (oh) d (p=0.001) was significantly lower in the t2dm group compared to the non-diabetic group. conclusion: we revealed that the serum level of 25 (oh) d is lower in patients with t2dm, and the tsh level is significantly higher compared to the non - diabetic group. thyroid dysfunction and a low level of 25 (oh) d are associated with a high risk of t2dm.