Subclinical Hypothyroidism Impact on the Characteristics of Patients with Polycystic Ovary Syndrome. A Meta-Analysis of Observational Studies

Background/Aims: Definitive polycystic ovary syndrome (PCOS) diagnosis should exclude thyroid dysfunctions. The purpose of the study is to examine the impact of subclinical hypothyroidism on the characteristics of PCOS patients. Methods: A meta-analysis of the published observational studies was conducted. Medline, Scopus, and Cochrane database search was performed to identify the studies that compared euthyroid PCOS and subclinical hypothyroidism (SCH)-PCOS patients. A total of 9 studies were selected, totalizing the inclusion of 1,537 euthyroid PCOS and 301 SCH-PCOS. The data were expressed as raw mean difference and standard error, using the random-effects model. Heterogeneity among studies was examined using the Cochran's test (Q) and I-2 statistics. Results: Anthropometrical parameters were similar in both groups. Total cholesterol (TC) and triglyceride (TG) were higher in SCH-PCOS (p = 0.036 and p = 0.012). High-density lipoprotein cholesterol was lower in the SCH-PCOS group (p = 0.018). Fasting glucose was lower in euthyroid PCOS (p = 0.022). All androgen levels were similar in both group (p > 0.05 for all). Conclusion: TC, TG and fasting glucose were higher in SCH-PCOS patients. Because of the heterogeneity among studies, some summarized results should be interpreted with caution. Consistent data for future studies addressing PCOS diagnosis are provided. (C) 2017 S. Karger AG, Basel