Introduction: Ghrelin is a novel peptide involved in the regulation of appetite and energy balance. Dysregulation of ghrelin may play a role in the development of obesity in polycystic ovary syndrome (PCOS). Due to the strong association between BMI and PCOS, we hypothesised that obese women with PCOS have abnormal fasting and post-glucose load ghrelin levels compared with BMI-matched control women.
Methods: Datasets included 18 women with PCOS, all with polycystic ovarian (PCO) morphology, hyperandrogenaemia and oligo-amenorrhoea (inter-menstrual interval >42 days). Controls were 18 BMI-matched women without PCO morphology, and with regular menstrual cycles. All women were of Europid origin and none were on medications likely to affect hormone concentrations. Fasting and +30 minute post-oral (75 g) glucose samples were taken.
Results: All variables were log transformed. Between PCOS and control groups, there were significant differences in ghrelin, both fasting (P<0.0001 unadjusted, P=0.01 adjusted) and 30 minute post-glucose (P=0.003 unadjusted, P=0.05 adjusted; Table 1). Linear regression multivariate analysis showed that HOMA IR (P=0.01) and testosterone (P=0.01) significantly and independently correlate with fasting ghrelin.
|Age (years)||BMI (Kgm−2)||G (fasting) (μg/ml)||G (+30 min) (μg/ml)||HOMAIR||T (nmol/l)|
|PCOS||30.1 (5.8)||33.8 (26.8, 42.8)||1098 (768, 1571)||936 (655, 1340)||2.09 (1.01, 4.31)||2.33 (1.68, 3.23)|
|Control||41.0 (3.6)||33.4 (27.9,39.9)||1807 (1310,2492)||1324 (1008,1740)||1.91 (1.02, 3.57)||1.60 (1.27, 2.01)|
|3t-test adjusted for age and BMI; G=Ghrelin; T=Testosterone|
Conclusion: Ghrelin levels (fasting and post-glucose) are significantly lower in PCOS women than BMI-matched controls. HOMA IR and serum testosterone significantly, independently and inversely correlate with fasting ghrelin, implying that ghrelin may have a role in PCOS aetiology.