[Subclinical hypothyroidism and endocrine metabolic characteristics in women with polycystic ovary syndrome].

To explore associations of subclinical hypothyroidism (SCH) with endocrine metabolic characteristics in women with polycystic ovary syndrome (PCOS).
 Methods: A total of 321 women who were newly diagnosed as PCOS were recruited from two endocrine outpatient clinics. The diagnosis of PCOS was established according to the 2003 Rotterdam consensus criteria. Thyroid function was examined by chemiluminescent immunoassay. Patients who had normal free thyroxine (FT4) were divided into different SCH subgroups according to two thyroid stimulating hormone (TSH) cutoff points (4.2 and 2.5 mU/L). Endocrine metabolic characteristics in different subgroups were compared and analyzed.
 Results: In PCOS women with normal FT4, the patients with TSH≥4.2 mU/L had higher prolactin (PRL), luteinizing hormone-to-follicle stimulating hormone ratio, and visceral adipose index (all P<0.05). There were trends toward an increase in triglyceride (P=0.085) and a decrease in high-density lipoprotein cholesterol (HDL-C) (P=0.060) in the patients with TSH≥4.2 mU/L compared with that in the patients with TSH<4.2 mU/L. Also in PCOS women with normal FT4, the patients with TSH≥2.5 mU/L had higher body mass index, PRL, triglyceride, visceral adipose index and lower HDL-C in comparison of that in the patients with TSH<2.5 mU/L (all P<0.05).
 Conclusion: SCH is associated with more severe endocrine abnormality, dyslipidemia, and visceral obesity in PCOS women. PCOS women with normal FT4 and endocrine metabolic characteristics are more prone to be different between the SCH group and the euthyroid group when setting 2.5 mU/L as a TSH cutoff for SCH, indicating that 2.5 mU/L is a good TSH cutoff for SCH in PCOS women.