Relationship between thyroid-stimulating hormone and blood lipids in patients with first-episode depression

Previous studies demonstrated thyroid stimulating hormone (TSH) plays an important role in regulating lipid metabolism, but the relationship between the two is controversial. Meanwhile, it has not been reported in a population with major depressive disorder (MDD).

We divided 1718 first-episode and drug naïve patients with MDD into a TSH abnormal group (TSH-AB) and a TSH normal group (TSH-NOR). The participants in the two groups were assessed by the Hamilton Depression Rating Scale (HAMD), Hamilton Anxiety Rating Scale (HAMA) and the positive subscale of Positive and Negative Syndrome Scale. The patients' blood was tested for TSH, free T3, free T4, fasting blood glucose, lipid indexes and body mass index was recorded.

The participants in the TSH-AB group had significantly higher HAMD scores, HAMA scores and total scores of positive symptoms, as well as higher incidence of suicide attempts than those in the TSH-NOR group, accompanied by significantly higher thyroglobulin antibodies, thyroid peroxidase antibodies, fasting blood glucose values, total cholesterol (TC), triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) levels compared with those of TSH-NOR patients. However, the high-density lipoprotein cholesterol (HDL-C) of TSH-AB patients was lower than those of TSH-NOR patients. TSH values were positively correlated with TC, TG, and LDL-C values, and negatively correlated with HDL-C value.

TSH was highly correlated with abnormal lipid metabolism in patients with MDD. The specific molecular mechanism of the relationship between TSH, lipid metabolism and the development of depression needs to be further in-depth investigation.