Dietary management of Polycystic ovary syndrome.

Abstract

Background Polycystic ovary syndrome (PCOS) is a common endocrine condition in women associated with obesity, reproductive and metabolic abnormalities. It improves with weight loss, however currently no specific dietary recommendations exist and there may be abnormalities in appetite regulation in PCOS that contribute to difficulty in weight management. Aims To assess the effect of 1) short and long-term weight loss and weight maintenance strategies on weight loss, reproductive and metabolic parameters in overweight women with PCOS and to 2) assess the relative effect of weight loss on cardiovascular risk factors and 3) postprandial appetite, appetite hormones (ghrelin, CCK, PYY) and food intake in overweight women with and without PCOS. Results Overweight women with PCOS followed an 8-week weight loss (2 meal replacements/day, 4904.4±127 kJ, n=32) followed by a 6 month carbohydrate (<120 g/day) or fat restricted (<50 g/day) weight maintenance regime (n=23). Reductions in weight (5.6±2.4 kg) and improvements in body composition, insulin, reproductive hormones and menstrual cyclicity occurred and were sustained equivalently for both diet groups. We then assessed the effect of weight loss (4.2±0.7 kg over 8 weeks as described above) in overweight women with (n=15) and without (n=17) PCOS on cardiovascular risk factors. All subjects had similar improvements in body composition, triglycerides, reproductive hormones and fasting and post-prandial insulin. C-reactive protein decreased with weight loss for non-PCOS women (-1.2±0.5 mg/L, P=0.025) but not for PCOS women. We finally assessed appetite regulation in PCOS. Women with (n=20) and without (n=12) PCOS followed a standard protein (55% carbohydrate, 15% protein) or high protein diet (40% carbohydrate, 30% protein) for 16 weeks (~6000 kJ/day). Non-PCOS subjects were more satiated (P=0.001) and less hungry (P=0.007) after the test meals and had a 70% higher fasting baseline ghrelin (P=0.011), a greater increase in fasting ghrelin (57.5 versus 34.0%, P=0.033), a greater post-prandial ghrelin decrease at week 16 (113.5±46.3 versus 49.3±12.2 pg/mL, P=0.05) and a greater maximal decrease in post-prandial ghrelin (-144.1±58.4 versus -28.9±14.2 pg/mL, P=0.02) following weight loss than subjects with PCOS. Lastly, women with (n=14) and without (n=14) PCOS undertook an 8-week weight loss regime (4.2±0.7 kg as described above). At week 0 and 8, women with PCOS again displayed lower ghrelin levels (P=0.01 and P=0.097 respectively) and a lesser post-prandial ghrelin decrease (P=0.048 and P=0.069 respectively) but similar post-prandial appetite, buffet consumption and fasting or post-prandial peptide YY and cholecystokinin compared to women without PCOS. Conclusion Meal replacements and moderate macronutrient restriction are effective strategies for the dietary management of PCOS. Equivalent weight losses improved cardiovascular risk factors similarly for overweight women with and without PCOS with the exception of CRP which did not decrease with weight loss for overweight women with PCOS. PCOS status is associated with altered fasting and post-prandial ghrelin levels but is not consistently associated with other impairments in post-prandial gut peptides or food intake. Further investigation is required to assess if appetite regulation is impaired in PCOS and the optimal strategies and amount of weight loss for improvement of reproductive and metabolic parameters in PCOS.