Introduction Metformin is one of the safest, first-line oral hypoglycemic agents used in type-2 diabetes mellitus patients. This study aims to study the effect of metformin on thyroid-stimulating hormone (TSH) in hypothyroid and euthyroid individuals, as both these diseases have an increased prevalence and coexistence. Method This hospital-based study was conducted in Jinnah Allama Iqbal Institute of Diabetes and Endocrinology (JAIDE), Allama Iqbal Medical College/Jinnah Hospital Lahore, Pakistan, from October 2019 to April 2020. One hundred and sixty type-2 diabetic participants, aged 25-60 years and meeting the inclusion criteria were enrolled in the study after informed consent. They were divided into two groups, the hypothyroid group who were already on levothyroxine therapy and had a stable TSH in the normal range, and a euthyroid group who had no thyroid dysfunction. Both the groups were started on metformin therapy for the control of type-2 diabetes mellitus and followed for six months. Their blood samples for TSH and free thyroid hormone (fT4) were drawn both prior to and after the study period. Results Out of the 160 type-2 diabetic patients, TSH levels showed a significant reduction in the hypothyroid patients (2.33 ± 0.70, p < 0.001) with no significant changes in the euthyroid patients (3.87 ± 0.40, p = 0.206) following six months of metformin therapy. However, there was no significant difference in the fT4 levels in either of the groups. Conclusion Metformin has the effect of significantly lowering TSH levels in hypothyroid individuals. However, no such effect was observed in euthyroid patients.

Background: Polycystic ovary syndrome (PCOS) is the most frequent pathology among women of reproductive age characterized by menstrual irregularities, hyperandrogenism and polycystic ovaries on ultrasound. Evidence suggests that high androgen levels are the fundamental factor in the pathogenesis of PCOS. The objectives of the present study was to determine serum free testosterone levels in polycystic ovarian syndrome patients, and observe its correlation with clinical hyperandrogenism. Patients and methods: This cross-sectional study was conducted at Jinnah Allama Iqbal Institute of Diabetes and Endocrinology Lahore, Pakistan from 15th May 2019 to 15th November 2019. The study included 140 patients of PCOS diagnosed as per Rotterdam criteria. Serum testosterone levels were determined in these patients by ELISA method. Ferriman-Gallwey (FG) score was used to assess severity of clinical hyperandrogenism in the form of hirsutism. Patients were categorized into three groups, mild (FG score 8-15), moderate (FG score 15-25) and severe (FG score >25). Correlation between clinical (hirsutism) and biochemical hyperandrogenism (serum free testosterone levels) was assessed using Fisher exact test. Data was analyzed using SPSS version 25. Results: Biochemical hyperandrogenism in the form of raised free testosterone levels was present in 46 (32.9%) PCOS patients. Out of 12 patients having Ferriman Gallwey score >25, 10 (83.3%) had biochemical hyperandrogenism. Out of 70 patients having Ferriman Gallwey score 15-25, 22 (31.4%) had biochemical hyperandrogenism whereas out of 58 patients having Ferriman Gallwey score 8-15, only 14 (24.1%) patients had biochemical hyperandrogenism. Conclusion: Prevalence of biochemical hyperandrogenism in PCOS patients in our studied population was significantly low when compared to the population studied worldwide making it less reliable as diagnostic tool in this part of the world. Also there was significant positive correlation between free testosterone levels and degree of hirsutism which means that diagnostic accuracy of free testosterone in PCOS patients is considerably high in those having clinical hyperandrogenism.