Lisa J. Moran

Impaired glucose tolerance, type 2 diabetes and metabolic syndrome in polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND Polycystic ovary syndrome (PCOS) is a common condition in reproductive-aged women associated with impaired glucose tolerance (IGT), type 2 diabetes mellitus (DM2) and the metabolic syndrome. METHODS A literature search was conducted (MEDLINE, CINAHL, EMBASE, clinical trial registries and hand-searching) identifying studies reporting prevalence or incidence of IGT, DM2 or metabolic syndrome in women with and without PCOS. Data were presented as odds ratio (OR) [95% confidence interval (CI)] with fixed- and random-effects meta-analysis by Mantel-Haenszel methods. Quality testing was based on Newcastle-Ottawa Scaling and The Cochrane Collaborations risk of bias assessment tool. Literature searching, data abstraction and quality appraisal were performed by two investigators. RESULTS A total of 2192 studies were reviewed and 35 were selected for final analysis. Women with PCOS had increased prevalence of IGT (OR 2.48, 95% CI 1.63, 3.77; BMI-matched studies OR 2.54, 95% CI 1.44, 4.47), DM2 (OR 4.43, 95% CI 4.06, 4.82; BMI-matched studies OR 4.00, 95% CI 1.97, 8.10) and metabolic syndrome (OR 2.88, 95% CI 2.40, 3.45; BMI-matched studies OR 2.20, 95% CI 1.36, 3.56). One study assessed IGT/DM2 incidence and reported no significant differences in DM2 incidence (OR 2.07, 95% CI 0.68, 6.30). One study assessed conversion from normal glucose tolerance to IGT/DM2 (OR 2.4, 95% CI 0.7, 8.0). No studies reported metabolic syndrome incidence. CONCLUSIONS Women with PCOS had an elevated prevalence of IGT, DM2 and metabolic syndrome in both BMI and non-BMI-matched studies. Few studies have determined IGT/DM2 or metabolic syndrome incidence in women with and without PCOS and further research is required.

Polycystic ovary syndrome: a complex condition with psychological, reproductive and metabolic manifestations that impacts on health across the lifespan

Polycystic ovary syndrome (PCOS) is of clinical and public health importance as it is very common, affecting up to one in five women of reproductive age. It has significant and diverse clinical implications including reproductive (infertility, hyperandrogenism, hirsutism), metabolic (insulin resistance, impaired glucose tolerance, type 2 diabetes mellitus, adverse cardiovascular risk profiles) and psychological features (increased anxiety, depression and worsened quality of life). Polycystic ovary syndrome is a heterogeneous condition and, as such, clinical and research agendas are broad and involve many disciplines. The phenotype varies widely depending on life stage, genotype, ethnicity and environmental factors including lifestyle and bodyweight. Importantly, PCOS has unique interactions with the ever increasing obesity prevalence worldwide as obesity-induced insulin resistance significantly exacerbates all the features of PCOS. Furthermore, it has clinical implications across the lifespan and is relevant to related family members with an increased risk for metabolic conditions reported in first-degree relatives. Therapy should focus on both the short and long-term reproductive, metabolic and psychological features. Given the aetiological role of insulin resistance and the impact of obesity on both hyperinsulinaemia and hyperandrogenism, multidisciplinary lifestyle improvement aimed at normalising insulin resistance, improving androgen status and aiding weight management is recognised as a crucial initial treatment strategy. Modest weight loss of 5% to 10% of initial body weight has been demonstrated to improve many of the features of PCOS. Management should focus on support, education, addressing psychological factors and strongly emphasising healthy lifestyle with targeted medical therapy as required. Monitoring and management of long-term metabolic complications is also an important part of routine clinical care. Comprehensive evidence-based guidelines are needed to aid early diagnosis, appropriate investigation, regular screening and treatment of this common condition. Whilst reproductive features of PCOS are well recognised and are covered here, this review focuses primarily on the less appreciated cardiometabolic and psychological features of PCOS.

Effects of energy-restricted high-protein, low-fat compared with standard-protein, low-fat diets: a meta-analysis of randomized controlled trials

BACKGROUND It is currently unclear whether altering the carbohydrate-to-protein ratio of low-fat, energy-restricted diets augments weight loss and cardiometabolic risk markers. OBJECTIVE The objective was to conduct a systematic review and meta-analysis of studies that compared energy-restricted, isocaloric, high-protein, low-fat (HP) diets with standard-protein, low-fat (SP) diets on weight loss, body composition, resting energy expenditure (REE), satiety and appetite, and cardiometabolic risk factors. DESIGN Systematic searches were conducted by using MEDLINE, EMBASE, PubMed, and the Cochrane Central Register of Controlled Trials to identify weight-loss trials that compared isocalorically prescribed diets matched for fat intake but that differed in protein and carbohydrate intakes in participants aged ≥18 y. Twenty-four trials that included 1063 individuals satisfied the inclusion criteria. RESULTS Mean (±SD) diet duration was 12.1 ± 9.3 wk. Compared with an SP diet, an HP diet produced more favorable changes in weighted mean differences for reductions in body weight (-0.79 kg; 95% CI: -1.50, -0.08 kg), fat mass (FM; -0.87 kg; 95% CI: -1.26, -0.48 kg), and triglycerides (-0.23 mmol/L; 95% CI: -0.33, -0.12 mmol/L) and mitigation of reductions in fat-free mass (FFM; 0.43 kg; 95% CI: 0.09, 0.78 kg) and REE (595.5 kJ/d; 95% CI: 67.0, 1124.1 kJ/d). Changes in fasting plasma glucose, fasting insulin, blood pressure, and total, LDL, and HDL cholesterol were similar across dietary treatments (P ≥ 0.20). Greater satiety with HP was reported in 3 of 5 studies. CONCLUSION Compared with an energy-restricted SP diet, an isocalorically prescribed HP diet provides modest benefits for reductions in body weight, FM, and triglycerides and for mitigating reductions in FFM and REE.

Treatment of obesity in polycystic ovary syndrome: a position statement of the Androgen Excess and Polycystic Ovary Syndrome Society

OBJECTIVE To summarize current evidence on lifestyle management (dietary, exercise, or behavioral interventions) of obesity in women with polycystic ovary syndrome (PCOS), to indicate gaps in knowledge, and to review the medical and surgical alternatives for weight management. DESIGN Expert panel appointed by the Androgen Excess and PCOS Society (AEPCOS Society) to review the literature and draft the initial report after a consensus process via electronic communication. The initial report was reviewed and critiqued by all expert panel members and the AEPCOS Society Board of Directors and modified based on their comments. CONCLUSION(S) Lifestyle management should be used as the primary therapy in overweight and obese women with PCOS for the treatment of metabolic complications. For reproductive abnormalities, lifestyle modification may improve ovulatory function and pregnancy. Data are preliminary for improvement in pregnancy and live-birth rates, and further research is needed. There is currently no evidence that modifying dietary macronutrient composition offers additional benefits over conventional dietary approaches for weight loss, and further research is needed. Emerging evidence suggests that exercise offers additional benefits to dietary energy restriction for reproductive features of PCOS.

The role of lifestyle modification in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine condition with reproductive and metabolic consequences, including anovulation, infertility and an increased prevalence of diabetes mellitus. Obesity, central obesity and insulin resistance are strongly implicated in its etiology and reduction of these risk factors should be a central treatment focus. Short-term weight loss has been consistently successful in reducing insulin resistance and restoring ovulation and fertility. However, problems arise with maintaining weight loss and precisely quantifying the associated long-term benefits of risk factor change. Although recent research indicates modest long-term lifestyle changes might reduce the extent of impaired glucose tolerance and delay the conversion to diabetes mellitus in the general population, this has not yet been examined in women with PCOS. Current conservative treatment should emphasize sustainable weight loss through dietary modification and exercise. Modifying additional lifestyle factors, including alcohol consumption, psychosocial stressors and smoking, are also crucial in long-term treatment of PCOS.

Overweight, obesity and central obesity in women with polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND Polycystic ovary syndrome (PCOS) is closely associated with obesity but the prevalence of obesity varies between published studies. The objective of this research was to describe the prevalence of overweight, obesity and central obesity in women with and without PCOS and to assess the confounding effect of ethnicity, geographic regions and the diagnostic criteria of PCOS on the prevalence. METHODS MEDLINE, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL) and PSYCINFO were searched for studies reporting the prevalence of overweight, obesity or central obesity in women with and without PCOS. Data were presented as prevalence (%) and risk ratio (RR) [95% confidence interval (CI)]. Random-effect models were used to calculate pooled RR. RESULTS This systematic review included 106 studies while the meta-analysis included 35 studies (15129 women). Women with PCOS had increased prevalence of overweight [RR (95% CI): 1.95 (1.52, 2.50)], obesity [2.77 (1.88, 4.10)] and central obesity [1.73 (1.31, 2.30)] compared with women without PCOS. The Caucasian women with PCOS had a greater increase in obesity prevalence than the Asian women with PCOS compared with women without PCOS [10.79 (5.36, 21.70) versus 2.31 (1.33, 4.00), P < 0.001 between subgroups). CONCLUSIONS Women with PCOS had a greater risk of overweight, obesity and central obesity. Although our findings support a positive association between obesity and PCOS, our conclusions are limited by the significant heterogeneity between studies and further studies are now required to determine the source of this heterogeneity. Clinical management of PCOS should include the prevention and management of overweight and obesity.

Metabolic features of the reproductive phenotypes of polycystic ovary syndrome

BACKGROUND Polycystic ovary syndrome (PCOS) is a common condition in women of reproductive age with well established metabolic abnormalities. There are numerous diagnostic criteria generating several reproductive diagnostic phenotypes [National Institute of Health (NIH) hyperandrogenic anovulatory PCOS and non-NIH PCOS including hyperandrogenic ovulatory or non-hyperandrogenic anovulatory PCOS]. There is ongoing debate regarding the optimal diagnostic criteria for PCOS and on the metabolic implications of newer non-NIH PCOS phenotypes. METHODS We reviewed the literature on the presence of risk factors for type 2 diabetes (DM2) and cardiovascular disease (CVD) across the reproductive diagnostic phenotypes of PCOS with the aims of comparing the metabolic features of the NIH and non-NIH groups and identifying potential high metabolic risk phenotypes of PCOS. RESULTS NIH PCOS patients present with greater obesity, abdominal obesity, insulin resistance (IR) and risk factors for DM2 and CVD compared with non-NIH ovulatory and non-hyperandrogenic PCOS patients. Where differences in metabolic features exist between the phenotypes, they are generally related to the degree of total and abdominal obesity. There is emerging evidence suggesting ovulatory and non-hyperandrogenic PCOS have greater metabolic abnormalities than controls primarily linked to abdominal adiposity. There is currently no evidence that non-hyperandrogenic PCOS is associated with a less adverse metabolic profile than ovulatory PCOS. CONCLUSIONS Current metabolic evidence appears to justify the inclusion of both non-NIH PCOS groups (ovulatory and non-hyperandrogenic) as PCOS subgroups. NIH PCOS is associated with a more adverse metabolic profile including greater total and abdominal obesity, IR and risk factors for CVD and DM2 than non-NIH phenotypes.

Assessment and management of polycystic ovary syndrome: summary of an evidence-based guideline.

Helena J Teede, Marie L Misso, Amanda A Deeks, Lisa J Moran, Bronwyn G A Stuckey, Jennifer L A Wong, Robert J Norman and Michael F Costello on behalf of the Guideline Development Groups

The effect of obesity on polycystic ovary syndrome: a systematic review and meta‐analysis

While many women with polycystic ovary syndrome (PCOS) are overweight, obese or centrally obese, the effect of excess weight on the outcomes of PCOS is inconsistent. The review aimed to assess the effects of overweight, obesity and central obesity on the reproductive, metabolic and psychological features of PCOS. MEDLINE, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL) and PSYCINFO were searched for studies reporting outcomes according to body mass index categories or body fat distribution. Data were presented as mean difference or risk ratio (95% confidence interval). This review included 30 eligible studies. Overweight or obese women with PCOS had decreased sex hormone‐binding globulin (SHBG), increased total testosterone, free androgen index, hirsutism, fasting glucose, fasting insulin, homeostatic model assessment‐insulin resistance index and worsened lipid profile. Obesity significantly worsened all metabolic and reproductive outcomes measured except for hirsutism when compared to normal weight women with PCOS. Overweight women had no differences in total testosterone, hirsutism, total‐cholesterol and low‐density lipoprotein‐cholesterol compared to normal weight women and no differences in SHBG and total testosterone compared to obese women. Central obesity was associated with higher fasting insulin levels. These results suggest that prevention and treatment of obesity is important for the management of PCOS.

Exercise therapy in polycystic ovary syndrome: a systematic review

BACKGROUND Polycystic ovary syndrome (PCOS) is a common endocrine disorder, affecting 8-12% of women. Lifestyle modification, including increased physical activity, is the first-line approach in managing PCOS. A systematic review was performed to identify and describe the effect of exercise as an independent intervention on clinical outcomes in PCOS. METHODS Five databases were searched with no time limit. A pre-specified definition of PCOS was not used. Studies were included if exercise therapy (aerobic and/or resistance) could be evaluated as an independent treatment against a comparison group. Outcomes measured included cardiovascular risk factors [insulin resistance (IR), lipid profiles, blood pressure and weight] and reproductive measures (ovulation, menstrual regularity and fertility outcomes). Quality analysis was performed based on the Cochrane Handbook of Systematic Reviews and the Quality of Reporting of Meta-Analyses checklist. RESULTS Eight manuscripts were identified (five randomized controlled trials and three cohort studies). All studies involved moderate intensity physical activity and most were of either 12 or 24 weeks duration with frequency and duration of exercise sessions ranging between studies. The most consistent improvements included improved ovulation, reduced IR (9-30%) and weight loss (4.5-10%). Improvements were not dependant on the type of exercise, frequency or length of exercise sessions. CONCLUSIONS Exercise-specific interventions in PCOS are limited. Studies vary considerably in design, intensity and outcome measures; therefore conclusive results remain elusive. Larger, optimally designed studies are needed to both gain insights into the mechanisms of exercise action and to evaluate the public health impact of exercise of PCOS.