Plasma Homocysteine and Insulin Resistance in Polycystic Ovary Syndrome

1. Plasma Homocysteine and Insulin Resistance in Polycystic Ovary Syndrome I. A. Hossain1, A. Sultana2, H. Chowdhury1, N. Sultana1 , S. Akter3, F. Jebunnesa3, L. Ali1,3. 1Dept of Biochemistry and Cell Biology, Biomedical Research Group, Dhaka, Bangladesh, 2Dept of Obstetrics and Gynecology, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic disorders, Dhaka, Bangladesh, 3Dept of Biochemistry and Cell Biology, Bangladesh Institute of Health Sciences, Dhaka, Bangladesh.

2. Background: • Polycystic ovary syndrome (PCOS) is the commonest endocrine disorder affecting 5-10% women of reproductive age. • Both genetic and environmental factors contribute to the development of PCOS.

3. Cont….. • Many studies suggest that PCOS may increase the risk of -Type 2 diabetes -Dyslipidemia -Hypertension -Cardiovascular disease • Exploration of the CVD risk factors in this disorder has lead to the suggestion that Hcy may be one of the important biochemical risk factors for PCOS and it is associated with insulin resistance and/or hyperinsulinemia • The observation has been debated and ethnic variation has also been reported

4. Cont…. • Therefore, plasma Hcy level and insulin resistance in PCOS subjects in our population needs to be investigated

5. Hypothesis • Plasma homocysteine is raised in PCOS women and it is associated with insulin resistance.

6. OBJECTIVES General Objective: • To investigate the homocysteinemic status in polycystic ovary syndrome and its association with insulin resistance Specific Objectives: • To measure the fasting plasma homocysteine level in subjects with PCOS. • To assess the glycemic and insulinemic status in polycystic ovary syndrome. • To investigate the association between plasma homocysteine and insulin resistance in polycystic ovary syndrome.

7. MATERIALS AND METHODS Study Design: • Cross-sectional study with case-control design. Place of the Study: • Dept of Gynecology & Obstetrics, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka and Biomedical Research Group, (BIRDEM), Dhaka

8. Cont…. Study population • After taking informed consent a total number of 215 women (121 PCOS women and 94 controls) were included • The final sample size was 146 (88 cases and 58 controls).

9. Cont…. Inclusion Criteria: • Cases were Bangladeshi subjects with PCOS, age between 15-40 years. • Controls were healthy and age matched Exclusion Criteria: • PCOS with known diabetes. • Relatives of PCOS. • Liver and renal disease and • PCOS with known endocrinopathy like hyperadrenalism, hypo and hyperthyroidism etc.

10. Analytical Methods and Lab Analysis: • Serum glucose was estimated by Glucose Oxidase method • Total cholesterol, TG and HDL were measured by enzymatic colorimetric method. • The LDL- Cholesterol level was calculated by using Friedewald formula [Friedewald WT 1972].

11. Analytical Methods and Lab Analysis: • Fasting serum C-peptide was estimated by ELISA (Millipore, USA) • Serum total L-homocysteine was measured by flourescence polarization immunoassay (FPIA) • Insulin secretion and sensitivity were calculated by homeostasis model assessment (HOMA) using HOMA–CIGMA software

12. Statistical method • The data expressed as the mean±SD and median (range) • Student’s Unpaired t test, Spearman's correlation and multiple linear regression were used for data analysis • All statistical analysis were performed with the SPSS software for windows 11.5

13. RESULTS Table 1: Anthropometric and Clinical characteristics of the study subjects

14. Table 2: Biochemical characteristics of the study subjects

15. Table 3: Glycemic, insulinemic and homocysteinemic status of the study subjects Results were expressed as Mean±SD. Means compared using Student’s Unpaired t-test. n=number of subjects; F Glu, Fasting glucose; AG, Serum glucose 2 hrs after 75 gm glucose load; C-pep:glu, C-peptide-glucose ratio; HOMA %B, B cell function assessed by homeostasis model assessment; HOMA %S, Insulin sensitivity assessed by homeostasis model assessment. Hcy, Homocysteine; PCOS, Polycystic ovary syndrome; R-PCOS, Relatives of PCOS subjects.

16. Table 4: Spearman’s Correlation of homocysteine with different variables in PCOS subjects The level of significance at p<0.05; r, Correlation coefficient.

17. Table 5: Spearman’s Correlation of homocysteine with different variables in the Control subjects The level of significance at p<0.05; r, Correlation coefficient

18. Table 6: Multiple linear regression taking serum homocysteine as dependent variable Dependent Variable: Hcy; Adjusted R2 =0.015

19. Conclusions: • PCOS is associated with hyperhomocysteinemia in Bangladeshi subjects • Both hyperinsulinemia and insulin resistance are present in PCOS, but the degree of hyperinsulinemia is disproportionately higher in PCOS compared to insulin resistance • Hyperhomocysteinemia in PCOS has mild degree of association with insulin resistance, but it seems to have strong association with hyperinsulinemia.

20. RECOMMENDATIONS • Measurement of Hcy and insulinemic status in PCOS subjects may be introduced in clinical practice to assess cardiovascular risk. • Large scale prospective studies should be undertaken to address the causal relationship between Hcy and insulinemic status.

21. Thank You

22. Sample Size Calculation The sample size was calculated according to the following formula (Bland, 2000): (µ1-µ2)2=f(α, P)σ2(1/n1+1/n2) Where, µ1-µ2=Difference between population means f(α, P)=[µα+µ2(1-P)]2, P=Power (80%) α=Significance level (0.05) σ2=Variance/mean difference within the group, n=Sample size

23. (µ1-µ2)2=f(α, P)σ2(1/n1+1/n2) (1.0)2= 7.9×(3.1)2(1/n+1/n) n= 7.9×8.0×9.61×2 n=152 Where, µ1-µ2=1.0 f(α, P)=[µα+µ2(1-P)]2, P= 7.9 (80%) α=Significance level (0.05) σ2=2.83,

24. LIMITATIONS • Due to lack of SHBG data Free Androgen Index could not be calculated and used in the diagnosis of PCOS. • Elaborate multivariate analysis, to get more insight regarding the risk factors, could not be done due to relatively smaller sample size.