The effect of glycaemic control in type 2 diabetic patients with subclinical hypothyroidism.

OBJECTIVE

The purpose of this study was to investigate the effect of glycaemic control on subclinical hypothyroidism (SCH) in Chinese type 2 diabetic patients.

METHODS

The study included 476 diabetic patients with SCH admitted for treatment of type 2 diabetes. The controls were selected euthyroid patients with similar characteristics regarding [age, body mass index (BMI), gender, previous hypertension or duration of diabetes, and smoke]. Total cholesterol (TC), LDL cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), the homeostatic model assessment of insulin resistance ratio (HOMA-IR), fasting plasma glucose, hemoglobin A (HbA), as well as plasma levels of thyrotrophin, and free thyroxine (FT4) were assessed at baseline and after 6 months of glycaemic control treatment.

RESULTS

The LDL-C level and HOMA-IR value were significantly higher in the SCH group. Glycaemic control reduced HOMA-IR, HbA, LDL-C, and TG level in patients with SCH. Furthermore, glycaemic control plays a negative effect on thyrotrophin in the SCH group, while this effect was not observed in euthyroid subjects. HbA plays a positive correlation with HOMA-IR (r = 0.048, p < 0.001), fasting plasma glucose (r = 0.086, p < 0.001), LDL-C (r = 0.062, p < 0.001) and TG (r = 0.021, p = 0.009).

CONCLUSION

Our study shows that glycaemic control may bring some benefits to type 2 diabetic patients with SCH.