High prevalence of polycystic ovary syndrome characteristics in girls with euthyroid chronic lymphocytic thyroiditis: a case–control study

ObjectiveThe aim was to find the prevalence of polycystic ovary syndrome (PCOS) phenotype in adolescent euthyroid girls with chronic lymphocytic thyroiditis (CLT).DesignThis was a prospective case–control study as part of an ongoing community-wide thyroid survey in Indian schools.MethodsOne hundred and seventy-five girls with euthyroid CLT and 46 age-matched non-CLT girls underwent clinical, biochemical, hormonal, and ultrasonographic evaluation for diagnosis of PCOS by Rotterdam 2003 criteria. All subjects underwent serum sampling for LH, FSH, testosterone, DHEAS, free thyroxine, TSH, and anti-thyroid peroxidase (TPO) antibodies. Oral glucose tolerance test (OGTT) was undertaken for plasma glucose and insulin.ResultsSignificantly higher prevalence of PCOS was noted in girls with euthyroid CLT when compared to their control counterparts (46.8 vs 4.3%,P=0.001). The CLT girls had higher body mass index, waist circumference, and systolic blood pressure (P=0.001). Mean number of menstrual cycles/year was 8.4±3.5 vs 10.1±1.4, and mean Ferriman–Gallwey score was 11.9±3.5 vs 3.0±2.4 (P=0.001) in cases versus controls respectively. The fasting and postprandial glucose and serum cholesterol were also higher in the cases (P=0.001). Homeostasis model assessment-insulin resistance was 4.4±4.2 vs 2.3±2.7 in the cases versus controls (P=0.001).ConclusionHigher prevalence of PCOS characteristics in euthyroid CLT girls when compared to controls suggest possible role of autoimmune phenomenon in the etiopathogenesis of PCOS. Further studies are required to understand the pathogenic link between these two disorders.