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. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1282329 / Thesis (Ph.D.) -- University of Adelaide, School of Paediatrics and Reproductive Health, 2007

Thesis (MNutr)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The role of fructose restriction in addition to dietary modifications for weight loss and lifestyle improvement, on fertility outcome and other markers of metabolic syndrome, in obese women with polycystic ovarian syndrome (PCOS) Introduction: At the time at which the current study was undertaken no data, as yet, existed on whether restriction of fructose, while treating obese patients with PCOS for weight loss, improves the clinical symptoms and metabolic/anthropometric profile so as to promote fertility. Objectives: To evaluate the baseline intake of fructose, as well as the effect of restricting fructose intake from fruit and soft beverages to less than 20 g daily, as well as to provide guidelines for weight loss on anthropometric measurements, for improving subjective clinical symptoms, and for promoting fertility outcome in obese patients with PCOS, who seek to become fertile. Methods: The study was conducted in the Tygerberg Hospital Infertility Clinic, as an experimental cohort. Patients with a body mass index (BMI) higher than 27, seeking fertility after diagnosis with PCOS, were referred for dietary consultation, and followed up 3 monthly over 1 year. At each visit anthropometric measurements and a detailed dietary history were taken and a questionnaire for clinical symptoms was completed. Results: Baselinely, 86 patients were included in the study. Averages for weight and BMI were 99.8 ± 24.3 kg and 39.2 ± 8.7kg/m2, respectively. Average baseline daily fructose intake was 167 ± 116.8g. At baseline, significant relationships were shown between fructose intake and burning feet (ρ=0.02) and frequent waking (ρ=0.02), with a trend towards nightly eating (ρ=0.07). The dropout rate after visit 1 was 50%, with a further dropout of 41% after visit 2. After 3 visits (n=18), fructose intake significantly reduced (ρ=0.018), with the significant relationships with clinical symptoms having disappeared by visit 2. After 3 visits (n=18), both weight and BMI decreased significantly (ρ=0.017) and (ρ=0.019), respectively. Fructose was tested as a covariate to BMI, with high significance (ρ=0.006) in said population group. Conclusion: Dietary intervention to reduce fructose intake proved significant for weight loss and BMI after 3 visits. Reduced fructose intake was associated with reduced clinical symptoms. With fructose being a significant covariate to BMI, it can be concluded that fructose overconsumption could possibly contribute to both clinical symptoms and elevated BMI in said study population. / AFRIKAANSE OPSOMMING: Die rol wat die beperking van fruktose speel bykomend tot dieetaanpassings en lewenstylverbetering vir gewigsverlies by oorgewig vroue met polisistiese ovariële sindroom (PCOS) in die uitkoms van fertiliteit en ander merkers van metaboliese sindroom. Inleiding: Met die aanvang van hierdie studie was daar is geen data beskikbaar oor die invloed van die beperking van fruktose in die dieet van oorgewig pasiënte met PCOS wat vir gewigsverlies behandel word nie. Dit was ook nie bekend of laasgenoemde pasiënte se kliniese simptome en metaboliese/antropometriese profiel sou verbeter met die beperking van fruktose sodat fertiliteit by hierdie pasiënte terselfdertyd ook bevorder word nie. Doelwitte: Die evaluering van die aanvanklike inname van fruktose, sowel as die beperking van fruktose afkomstig van eetbare vrugte en versoete drankies en sap tot ’n inname van minder as 20 g daagliks, tesame met riglyne vir gewigsverlies. Die uitkoms hiervan is bepaal deur antropometriese metings, die verbetering in subjektiewe kliniese simptome en die fertiliteituitkoms by oorgewig pasiënte wat hulp met fertiliteit verlang. Metodes: Die studie het as ’n eksperimentele kohort by die Infertiliteitskliniek by Tygerberg Hospitaal plaasgevind. Pasiënte wat na diagnose met PCOS fertiliteitsbehandeling verlang het en ’n BMI hoër as 27 gehad het , is vir dieetbehandeling verwys en driemaandeliks oor ’n tydperk van een jaar opgevolg. Tydens elke besoek is antropometriese metings en ’n omvattende dieetgeskiedenis geneem en ’n vraelys oor kliniese simptome ingevul. Resultate: Aanvanklik is 86 pasiënte by die studie ingesluit. Gemiddeldes vir gewig en BMI was 99.8 ± 24.3 kg en 39.2 ± 8.7 kg/m2 respektiewelik. Gemiddelde aanvanklike daaglikse inname van fruktose was 167 ± 116.8 g. Oorspronklik het betekenisvolle verhoudings tussen fruktose en die volgende bestaan: brandvoete (ρ=0.02) en veelvuldige episodes van nagtelike wakkerheid (ρ=0.02), met ’n neiging na nagtelike etery (ρ=0.07). Die uitvalsyfer na een besoek was 50% met ’n verdere uitvalsyfer van 41% na die tweede besoek. Na drie besoeke (n=18) het sowel die gewig as die BMI betekenisvolle afname getoon (ρ= 0.017) en (ρ=0.019), respektiewelik. Fruktose is as ’n belangrike kovariant vir BMI (ρ= 0.006) vir hierdie populasiegroep geïdentifiseer. Gevolgtrekking: Dieetintervensie vir die vermindering van die inname van fruktose was beduidend vir gewigsverlies en afname in BMI na drie besoeke. Verminderde fruktose-inname het gelei tot die vermindering van kliniese simptome. Met fruktose as beduidende kovariant vir BMI kan die gevolgtrekking gemaak word dat die oor-inname van fruktose by hierdie studiepopulasie waarskynlik tot sowel kliniese simptome as BMI bygedra het.