Background: Polycystic ovary syndrome (PCOS) is a complex,
multifactorial endocrine disorder affecting 5%- 10% of all women of
reproductive age. Insulin resistance (IR), a subnormal target tissue response
to a given amount of insulin, is a common feature, but not a diagnostic
criterion of PCOS. Due to the severe consequences PCOS exerts on the health and
lifestyle of the affected women and IR adding upon those risks, it is of utmost
importance to unravel the intricate pathophysiologic cross-link between PCOS
and IR.
Objectives: The aim of this study is to evaluate the
intricate pathophysiologic cross-link between PCOS and IR. To determine if
Homeostatic model assessment (HOMA) & Glucose insulin ratio (G:I) can be
used as a simple marker to identify PCOS patients at risk for Impaired Glucose
Tolerance (IGT) and Type II diabetes mellitus (DM).
Methodology: This hospital-based cross-sectional study was
carried out in the Department of Biochemistry in collaboration with the
Gynaecology & Obstetrics Department, Rajarajeswari Medical College and
Hospital, Bengaluru. It was done over a period of 6 months from February 2015
to July 2015. The study was conducted with 85 women, 45 PCOS cases (USG
diagnosed) and 40 controls (with regular menstrual cycle) in the age group of
20-40 years. Insulin resistance indices, namely, Fasting Insulin, Glucose
insulin ratio (G:I) and Homeostatic model assessment (HOMA) were calculated
from the values of Fasting blood sugar and fasting Insulin estimated by
Chemiluminiscence immunoassay. Cases and controls were further subdivided based
on age as Group I (20-30 yrs) and Group II (31-40 yrs).
Results: Fasting blood sugar, fasting insulin, G:I and HOMA
were significantly higher (P = 0.0137, 0.0018, 0.0475 and 0.0047, respectively)
in cases than in controls. IR was found in 31 out of 45 (68.88%) by the G:I
ratio, 26 out of 45 (57.77%) cases by HOMA (<2.5) and 15 out of 45 (33.33%)
by Fasting Insulin. There was no significant difference between cases and
controls with respect to age, BMI and waist circumference (P = 0.7342, 0.3538
and 0.4841, respectively). When the cases were subdivided, BMI was significantly
higher (P 0.0001) in Group II as compared to Group I. IR markers like Fasting
insulin, and HOMA were higher in Group I compared to Group II, but not
statistically significant.
Conclusion: Fasting Insulin, HOMA and G:I can be used as a
simple, practical and effective marker to identify PCOS patients who are at
risk of Type II DM. The data suggests that patients having Fasting Insulin >
20 IU, HOMA >2.5 & G:I < 4.5 should be closely monitored and
considered as high risk for Type II DM. Since this study was cross-sectional, a
longitudinal study as a prospective cohort study, is needed to evaluate the
predictive value of HOMA and G:I ratios for future development of IGT and type
II diabetes in PCOS patients. Additionally, as the research was conducted at a
single centre with a small sample size, future studies should involve larger,
multicenter cohorts to further explore the intricate pathophysiologic
relationship between PCOS and insulin resistance.
Author(s) Details
Montey Naruka
Department of Biochemistry, Rajarajeswari Medical College and Hospital,
Bangalore, India.
S. M. R. Usha
Department of Biochemistry, Rajarajeswari Medical College and Hospital,
Bangalore, India.
B. M. Rupakala
Department of Gynecology and Obstetrics, Rajarajeswari Medical College and
Hospital, Bangalore, India.
P. Vijaya Lakshmi
Department of Biochemistry, Rajarajeswari Medical College and Hospital,
Bangalore, India.
Please see the book here :- https://doi.org/10.9734/bpi/cbrp/v8/6710
