Moving beyond Weight: A Narrative Review of the Dietary and Lifestyle Management for Reducing Cardiometabolic Risk in Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder experienced by women. PCOS is a lifelong condition associated with reproductive, metabolic, and psychological presentations. PCOS is also linked with increased prevalence of cardiometabolic risk factors. While an association between body weight and PCOS has been noted, cardiometabolic risk factors are prevalent in individuals with PCOS across body weights. Currently, no consensus exists as to the most appropriate lifestyle strategy for mitigating cardiometabolic risk in PCOS. A large proportion of the literature is focused on weight loss for individuals with PCOS who are overweight or experience obesity, despite PCOS being prevalent across body sizes. The aim of this narrative review is to assess dietary and lifestyle interventions aimed at reducing cardiometabolic risk in individuals with PCOS across body sizes. A total of 51 articles are included in this review. Overall, randomized controlled trials are limited and most studies focus on weight loss, excluding individuals classified within a healthy body weight range. Studies that modified the dietary pattern without an energy deficit saw improvements in cardiometabolic risk. Thus, less restrictive dietary approaches may be effective at reducing cardiometabolic risk in this population. This review also highlights the need for more sustainable lifestyle interventions that meet the needs of individuals with PCOS of varying body weights.

Use of the Single Cell Gel Electrophoresis Assay for the Detection of DNA-protective Dietary Factors: Results of Human Intervention Studies

The single cell gel electrophoresis technique is based on the measurement of DNA migration in an electric field and enables to investigate via determination of DNA-damage the impact of foods and their constituents on the genetic stability. DNA-damage leads to adverse effects including cancer, neurodegenerative disorders and infertility. In the last 25 years approximately 90 human intervention trials have been published in which DNA-damage, formation of oxidized bases, alterations of the sensitivity towards reactive oxygen species and chemicals and of repair functions were investigated with this technique. In approximately 50% of the studies protective effects were observed. Pronounced protection was found with certain plant foods (spinach, kiwi fruits, onions), coffee, green tea, honey and olive oil. Also diets with increased contents of vegetables caused positive effects. Small amounts of certain phenolics (gallic acid, xanthohumol) prevented oxidative damage of DNA; with antioxidant vitamins and cholecalciferol protective effects were only detected after intake of doses that exceed the recommended daily uptake values. The evaluation of the quality of the studies showed that many have methodological shortcomings (lack of controls, no calibration of repair enzymes, inadequate control of the compliance and statistical analyses) which should be avoided in future investigations.

Lifestyle management in polycystic ovary syndrome - beyond diet and physical activity

Polycystic ovary syndrome (PCOS) is a common condition affecting reproductive-aged women with reproductive, metabolic and psychological consequences. Weight and lifestyle (diet, physical activity and behavioural) management are first-line therapy in international evidence-based guidelines for PCOS. While these recommend following population-level diet and physical activity guidelines, there is ongoing interest and research in the potential benefit of including psychological and sleep interventions, as well as a range of traditional, complimentary and integrative medicine (TCIM) approaches, for optimal management of PCOS. There is limited evidence to recommend a specific diet composition for PCOS with approaches including modifying protein, carbohydrate or fat quality or quantity generally having similar effects on the presentations of PCOS. With regards to physical activity, promising evidence supports the provision of vigorous aerobic exercise, which has been shown to improve body composition, cardiorespiratory fitness and insulin resistance. Psychological and sleep interventions are also important considerations, with women displaying poor emotional wellbeing and higher rates of clinical and subclinical sleep disturbance, potentially limiting their ability to make positive lifestyle change. While optimising sleep and emotional wellbeing may aid symptom management in PCOS, research exploring the efficacy of clinical interventions is lacking. Uptake of TCIM approaches, in particular supplement and herbal medicine use, by women with PCOS is growing. However, there is currently insufficient evidence to support integration into routine clinical practice. Research investigating inositol supplementation have produced the most promising findings, showing improved metabolic profiles and reduced hyperandrogenism. Findings for other supplements, herbal medicines, acupuncture and yoga is so far inconsistent, and to reduce heterogeneity more research in specific PCOS populations, (e.g. defined age and BMI ranges) and consistent approaches to intervention delivery, duration and comparators are needed. While there are a range of lifestyle components in addition to population-recommendations for diet and physical activity of potential benefit in PCOS, robust clinical trials are warranted to expand the relatively limited evidence-base regarding holistic lifestyle management. With consumer interest in holistic healthcare rising, healthcare providers will be required to broaden their knowledge pertaining to how these therapies can be safely and appropriately utilised as adjuncts to conventional medical management.

Changes in anthropometric, biochemical, oxidative, and DNA damage parameters after 3-weeks-567-kcal-hospital-controlled-VLCD in severely obese patients with BMI ≥ 35 kg m-2

BACKGROUND & AIMS

Severe obesity and its comorbidities relate to increased genomic instability/cancer risk. Obesity in Croatia is rapidly increasing, and long diets are sometimes the reason for obese to quit health improvement programs. A shorter diet with more strict calorie reduction could also lead to weight reduction and health improvements, but data are scarce. We tested for the first time if a very low-calorie diet (VLCD) can improve anthropometric, biochemical and genomic stability parameters in severely obese with BMI ≥ 35 kg m^-2.

METHODS

22 participants were chosen among those regularly attending the hospital for obesity control, with no other previous treatment for bodyweight reduction. Under 24 h medical surveillance, patients received 3-weeks-567-kcal-hospital-controlled-VLCD composed of 50-60% complex carbohydrates, 20-25% proteins, and 25-30% fat, with the attention to food carbo-glycemic index, in 3 meals freshly prepared in hospital. We analyzed changes in body weight, BMI, basal metabolism rate, waist-hip ratio, visceral fat level, body fat mass, percent body fat, skeletal muscle mass, basal metabolism, energy intake, lipid profile, thyroid hormones, TSH, and genomic instability (alkaline and oxidative FPG comet assay) before and on the last VLCD day.

RESULTS

Diet caused BMI reduction (in average 3-4 BMI units' loss), excessive weight loss (between 10 and 35%), significant weight loss (average 9 kg, range 4.8-14.4 kg) and a significant decrease in glucose, insulin, urea, cholesterol, HDL-c, LDL-c, oxidative (FPG) and DNA damage (alkaline comet assay) levels.

CONCLUSIONS

The diet can lead to ≥10% excessive weight loss, significant health, and genomic stability improvement, and keep severely obese interest in maintaining healthy habits. The study was registered at ClinicalTrials.gov as NCT05007171 (10.08.2021).

Does Organic Sprouted Whole Wheat Grain Flourless Bread Decreases DNA Damage in Diabetic Patients?

Diabetes is one of the main health concerns, especially in developed countries. During the last few decades, the percentage of diabetic persons is constantly increasing. Although the genetic factors have a strong influence in the development of diabetes, environmental influence (physical inactivity, inadequate nutrition leading to obesity) also have an important impact. The main objective of this investigation was to evaluate the possible influence of organic sprouted whole wheat grain flourless bread Tonus® (product of Trivit, Becej, Serbia) on DNA damage at various stages of progression through type 2 diabetes mellitus (T2DM). In addition to control (non-diabetic) subjects we analyzed obese, pre-diabetic and diabetic patients, for a total of four experimental groups. All subjects used to eat Mediterranean diet for at least two years before being included in our study. In each of four groups we had five persons practicing the Mediterranean diet but instead of bread they consumed flourless bread Tonus®. The DNA damage was evaluated on peripheral blood mononuclear cells by alkaline single cell gel electrophoresis (Comet) assay at the very beginning (before starting the Tonus® bread diet), and after exactly the three months of consumption of Tonus® bread. Statistical analysis revealed that only in patients with type 2 diabetes, Tonus® bread intake led to decreased DNA damage compared to the level of DNA damage of these patients before they started Tonus® bread diet. We assume that decrease of body weight and hyperinsulinemia caused by Tonus® bread in the diet might be one of the main causes of decreased DNA damage.

Dietary and Physical Activity Habits in Adolescent Girls with Polycystic Ovary Syndrome (PCOS)-HAstudy

The role of inappropriate lifestyle in the etiology of polycystic ovary syndrome (PCOS) and its metabolic and reproductive complications has attracted much attention in recent years; however, most studies involve adult patients. Thus, the study aimed to compare dietary patterns, physical activity, metabolic, anthropometric and inflammatory markers of 14-18-year-old girls with and without PCOS (n = 61 and n = 35, respectively) as well as to assess correlations between concentrations of metabolic and inflammatory markers and macronutrient intake and to identify the independent predictors of PCOS, related to diet and physical activity (PA). Compared to the control group, PCOS girls consumed significantly more total fat (p = 0.0005), including both saturated (SFA) (p = 0.03), monounsaturated (MUFA) (p = 0.0003) and polyunsaturated fatty acids (PUFA) (p = 0.01). A significantly higher percentage of PCOS patients consumed high and medium glycemic index (GI) foods (p = 0.03) and represented a low level of PA, both during school and in leisure time (41.67 vs. 6.06%; p = 0.0001 and 32.79 vs. 5.71%; p = 0.003, respectively). The PCOS group had also significantly higher waist circumference (WC), C-reactive protein (CRP) (p = 0.01), LDL cholesterol (p = 0.01), fasting insulin (p = 0.002) and HOMA-IR (p = 0.006) levels. There was an inverse correlation between fiber intake and fasting insulin, (p = 0.0002, r = -0.37), HOMA-IR (p = 0.0004, r = -0.35), WC (p = 0.029; r = -0.222) and a positive relationship between high and medium GI diet and insulin concentration (p = 0.003; r = 0.3). An increase of 10 g/day in total fat intake per day increases the probability of PCOS by 1.4 times. If the SFA or MUFA intakes increase by 10 g, the probability of PCOS increase 1.7-fold and 2.5-fold, respectively. The consumption of foods with a medium GI raises the probability of PCOS by more than 3 times, after adjusting for age. The odds ratio decreased for the moderate and high PA at school/work and in leisure time. Further research in girls with PCOS is needed to test whether low GI and dietary fatty acid reduction combined with increased PA is effective in the nonpharmacological treatment and prevention of PCOS complications. ClinicalTrial.gov Identifier: NCT04738409.

Metabolic profile of women with PCOS in Brazil: a systematic review and meta-analysis

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disease affecting women of reproductive age and associated with reproductive and metabolic dysfunction. Few studies are available regarding metabolic traits in Brazilian women with PCOS. The aim of this systematic review and meta-analysis was to summarize the available evidence regarding metabolic traits and comorbidities in Brazilian women with polycystic ovary syndrome (PCOS).

METHODS

We systematically searched PubMed, Cochrane Central Register of Controlled Trials, and Embase for cross-sectional, case-control, or cohort studies focusing on populations of different regions from Brazil, published until July 31, 2019. Studies were selected if they reported PCOS diagnostic criteria. Studies without a control group were included if they presented relevant metabolic data.

RESULTS

Of 4856 studies initially identified, 27 were included in the systematic review and 12 were included in the meta-analysis, for a total of 995 women with PCOS defined by Rotterdam criteria and 2275 controls from different regions of Brazil. Obesity, metabolic syndrome and IGT were prevalent, and standard mean differences for BMI (SMD 0.67, 95% CI, 0.29, 1.05), waist circumference (SMD 0.22, 95% CI 0.02, 0.41), systolic (SMD 0.66, 95% CI 0.30, 1.01) and diastolic blood pressure (SMD 0.55, 95% CI 0.24, 0.87), glucose (SMD 0.21, 95% CI 0.04, 0.38) and HOMA (SMD 0.78, 95% CI 0.52, 1.04) were significantly higher in Brazilian women with PCOS compared to controls. Lipid profile was more adverse in PCOS vs. non-PCOS women. Between-study heterogeneities were low/moderate for glucose and HOMA and moderate/high for the other variables.

CONCLUSIONS

The data of this systematic review and meta-analysis indicate that Brazilian women with PCOS have a worse metabolic profile than women without PCOS with no important regional differences. The prevalence of metabolic changes is intermediate in Brazil vs. other countries.

Metabolic Features of Women With Polycystic Ovary Syndrome in Latin America: A Systematic Review

BACKGROUND

Polycystic ovary syndrome (PCOS) is an endocrine disorder that commonly affects women of childbearing age and has been associated with metabolic and reproductive abnormalities. Only a few studies have investigated metabolic traits in women with PCOS in Latin America. Therefore, we conducted a systematic review to provide an overview of the available evidence on the metabolic profile of Latin American women with PCOS.

METHODS

We searched PubMed, Cochrane Central Register of Controlled Trials, and Embase databases for cross-sectional, case-control, or cohort studies focusing on populations of countries in South and Central America and Mexico, published until October 31, 2019. We selected studies that reported the diagnostic criteria for PCOS. In the absence of a control group, we included studies if they reported relevant metabolic data.

RESULTS

The initial search yielded 4878 records, of which 41 studies were included in the systematic review. Sample sizes ranged from 10 to 288 in PCOS groups and from 10 to 1500 in control groups. The prevalence of phenotypes A and B (classic PCOS) ranged from 65.8% to 87.5% as reported in studies from Argentina, Brazil, and Chile. Metabolic syndrome ranged from 33.3% to 44.0% for phenotype A, from 15.0% to 58.0% for phenotype B, from 11.9% to 36.0% for phenotype C, and from 14.2% to 66.0% for phenotype D. Women with PCOS had higher body mass index, waist circumference, blood pressure, glucose, and homeostasis model assessment index as well as a more adverse lipid profile than those without PCOS.

CONCLUSIONS

Evidence from the present systematic review suggests that anthropometric and metabolic profiles are worse in women with PCOS who live in different Latin American countries than in women without PCOS living in the same region. Additional studies assessing metabolic comorbidities, such as diabetes, and distinct PCOS phenotypes in different Latin American countries are warranted and may produce invaluable information for primary and secondary prevention of PCOS in the region. This systematic review was registered with PROSPERO under number CRD42016038537.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, identifier CRD42016038537.

Risk Factors of Overweight and Obesity Related to Diet and Disordered Eating Attitudes in Adolescent Girls with Clinical Features of Polycystic Ovary Syndrome

Background: We aimed to find the difference between girls with clinical features of Polycystic ovary syndrome (PCOS), divided into two groups: Overweight/obesity (Ov/Ob) and normal weight (N), related to diet, disordered eating attitudes (DEA), metabolic and hormonal differences, and to identify the risk factors of being overweight or obese. Methods: Seventy-eight adolescents with PCOS, aged 14-18 years, were divided into Ov/Ob and N groups. Patients underwent blood tests for determination of follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone, DHEA-S, estradiol, of sex hormone-binding globulin (SHBG), fasting glucose, insulin, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), and lipid profile. Nutrition was evaluated using a 3-day food record. To examine the level of DEA, the Eating Attitudes Test-26 (EAT-26) was used. We defined an EAT-26 score ≥20 as positive for DEA. Logistic regression was carried out to identify the independent predictors of being overweight and obese. Results: An increase of 10 g in plant protein intake decreased the probability of being overweight and of obesity (OR = 0.54; p = 0.036). EAT-26 score ≥20 was correlated with a 7-fold (OR = 6.88; p = 0.02) increased odds of being overweight or of obesity. Conclusion: Being overweight and obesity in adolescents with PCOS may be associated with DEA and the type and amount of protein intake.

Adherence to diet quality indices in relation to semen quality and reproductive hormones in young men

STUDY QUESTION

Is adherence to an a priori defined diet quality indices [Alternate Healthy Index 2010 (AHEI-2010), relative Mediterranean diet score (rMED) or dietary approaches to stop hypertension (DASH)] associated with semen quality and reproductive hormone levels in young men?

SUMMARY ANSWER

Greater adherence to the DASH diet is related to higher sperm counts.

WHAT IS KNOWN ALREADY

Studies assessing the relationship between dietary intake and male reproductive function have mainly been focused on specific nutrients, food groups or data-driven dietary patterns, but the evidence on a priori defined dietary indices is still scarce.

STUDY DESIGN, SIZE, DURATION

Cross-sectional study of 209 male university students recruited from October 2010 to November 2011 in Murcia Region (Southern Spain).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Healthy young men aged 18-23 years were included in this study. Diet was assessed using a validated food frequency questionnaire and three a priori-defined dietary indices (AHEI-2010, rMED and DASH) were calculated. Linear regression was used to analyze the relation between the three dietary indices and semen quality parameters and reproductive hormone levels accounting for potential confounders and covariates.

MAIN RESULTS AND THE ROLE OF CHANCE

We found statistically significant positive associations between the DASH index and sperm concentration (P, trend = 0.04), total sperm count (P, trend = 0.04) and total motile sperm count (P, trend = 0.02). No associations were observed for other semen parameters or male reproductive hormones.

LIMITATIONS, REASONS FOR CAUTION

Even though we adjusted for several known and suspected confounders we cannot exclude the possibility of residual or unmeasured confounding or chance findings. Subjects were blinded to the study outcomes thus reducing the potential influence on their report of diet. Our sample size may be too small to rule out associations with other semen parameters or reproductive hormones. Causal inference is limited, as usual with all observational studies.

WIDER IMPLICATIONS OF THE FINDINGS

The results suggest that greater adherence to the DASH may help improve sperm counts. This study was carried out on young men from the general population. However, results may differ among other populations (e.g. infertile men). Therefore, further research is needed to confirm these findings and extend these results to other populations.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by Fundación Séneca, grants No 08808/PI/08 and No 19443/PI/14; Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III (AES), grants No PI10/00985 and No PI13/01237; and grant P30DK046200 from the National Institutes of Health. Authors have no competing interests to declare.

Influence of bariatric surgery induced weight loss on oxidative DNA damage

Obesity is associated with elevated cancer risk, which may be represented by elevated genomic damage. Oxidative stress plays a key role in obesity related detrimental health consequences including DNA oxidation damage. The elevated cancer risk in obesity may be a consequence. Weight loss has been shown to reduce genomic damage, but the role of oxidative stress in that has not been clarified. The aim of this study is therefore to investigate the influence of bariatric surgery induced weight loss on DNA oxidation damage in morbidly obese subjects. For this aim, we used cryopreserved peripheral blood mononuclear cells in the FPG comet assay. Advanced protein oxidation products and 3-nitrotyrosine were measured as oxidative and nitrative protein stress markers. Furthermore, expression of oxidative stress related proteins HSP70 and Nrf2 as well as mitochondrial enzyme citrate synthase and NADPH oxidase subunit p22 phox were analysed. Our findings revealed significantly reduced DNA strand breaks, but DNA base oxidation was not reduced. We observed significant reduction in plasma AOPPs and 3-nitrotyrosine, which indicated an improvement in oxidative/nitrative stress. However, expression of HSP70 and Nrf2 were not altered after weight loss. In addition, expression of citrate synthase and p22 phox were also unaltered. Overall, bariatric surgery induced significant reduction in excess body weight and improved the patients' health status, including reduced DNA strand breaks and slightly improved antioxidant status in some of the investigated endpoints, while cellular ROS formation and DNA oxidation damage stayed unaltered. This complex situation may be due to combined beneficial effects of weight loss and burdening of the body with fat breakdown products. In the future, collecting samples two years after surgery, when patients have been in a weight plateau for some time, might be a promising approach.

Diets with lower carbohydrate concentrations improve insulin sensitivity in women with polycystic ovary syndrome: A meta-analysis

OBJECTIVE

Women with polycystic ovary syndrome (PCOS) are associated with increased levels of insulin resistance (IR). Other than treatment with insulin-sensitizing drugs, specialized diets have also been implemented to reduce the patient's IR. However, the capacity of certain diets, concerning with the severity of the patient's IR, to improve insulin sensitivity has not fully been explored. Therefore, we conducted a meta-analysis to determine in PCOS subjects from low to severe IR, if hypocaloric diets improve insulin sensitivity.

STUDY DESIGN

PubMed, SCOPUS, EBSCO, and LILACS databases and retrieved studies' bibliographies were searched for prospective studies that investigated the association between diets and IR in PCOS women until October 2018. Diet was defined as a modification of the patients' nutrition intake according to caloric restriction, change in protein intake, or by using a specialized diet. IR measures (HOMA1-IR), pre- and post-intervention were extracted. Using Comprehensive Meta-Analysis software, depending on the level heterogeneity, determined by the ψ²-based Q-test and the I²-test, fixed-effects or random-effects models were used to calculate the pooled standard paired differences (SPD) and 95 %CI.

RESULTS

20 publications (25 studies) fulfilled the inclusion criteria. Due to the heterogeneity of the diets, the random-effects model was used. In 48 % of the studies, the diets led to a decrease of IR, where 44 % had no effect. In 2 studies, the diets increased IR. Overall, the diets decreased IR (SPD=-0.58; 95 %CI: -0.81 to -0.36). Subjects with severe IR (HOMA1-IR>4.2) had a marked improvement (SPD=-1.22; 95 %CI: -1.61 to -0.84). Moreover, diets low in carbohydrate (<50 %) was also determined to improve IR (SPD=-0.86; 95 %CI: -1.23 to -0.50).

CONCLUSIONS

Here, we demonstrate that diets are more likely to improve IR in PCOS women with severe IR. Therefore, it is crucial to determine a subject's IR status before considering any intervention containing a diet.

TNF-α G-308A genetic variants, serum CRP-hs concentration and DNA damage in obese women

Obesity is associated with inflammation, which can disturb genome stability. Tumor necrosis factor (TNF-α) polymorphism was found to affect TNF-α protein production and inflammation. Therefore, the present study illustrates the relationship between TNF-α polymorphism, the degree of inflammation assessed by serum high sensitivity C-reactive protein concentration (CRP-hs) and basal DNA damage in patients with obesity (BMI 30–34.9 kg/m²) and control subjects with proper body mass (BMI < 25 kg/m²). A total of 115 participants (75 obese premenopausal women; and 40 age-, and gender-matched controls) were included. Biochemical parameters (serum concentrations of total-cholesterol, HDL-cholesterol, LDL- cholesterol, triglycerides, glucose, apolipoprotein AI, CRP-hs) and endogenous DNA damage (determined by comet assay) were measured. TNF-α G-308A polymorphism (rs1800629) was analyzed by PCR-RFLP (PCR-restriction fragments length polymorphism). An effect of TNF-α genotype on serum CRP-hs concentration was noted (p = 0.031). In general, carriers of the rare A allele of the TNF-α G-308A polymorphism had significantly lower endogenous DNA damage and serum CRP-hs concentrations than GG homozygotes, however, the protective effect of the A allele was especially visible in non-obese women. Serum CRP-hs concentrations and levels of DNA damage (% DNA in tail) were significantly higher in obese than in controls (p = 0.001 and p < 0.0001, respectively). The adjusted multiple linear regression analyses revealed a significant, independent impact of obesity on DNA damage (p = 0.00000) and no effect of other covariates i.e. age, TNF-α genotype and serum CRP-hs concentration. Our study showed that obesity has a significant impact on the levels of endogenous DNA damage. Obesity abolished the protective effect of A allele of the TNF-α G-308A polymorphism on DNA damage and on inflammation development observed in non-obese A allele carriers.

Reduction of DNA damage in peripheral lymphocytes of obese patients after bariatric surgery-mediated weight loss

Obesity is associated with several detrimental health consequences, among them an increased risk for development of cancer, and an overall elevated mortality. Multiple factors like hyperinsulinemia, chronic microinflammation and oxidative stress may be involved. The comet assay has been proven to be very sensitive for detection of DNA damage and has been used to explore the relationship between overweight/obesity and DNA damage, but results are controversial. Very few investigations have been performed to correlate weight loss of obese individuals and possible reduction of DNA damage and these studies have not provided clear results. As currently, only surgical interventions (metabolic/bariatric surgery) enable substantial and sustained weight loss in the vast majority of morbidly obese patients, we analyzed whole blood samples of 56 subsequent patients prior, 6 and 12 months after bariatric surgery. No reduction of DNA damage was observed in comet assay analysis after 6 months despite efficient weight loss, but a significant reduction was observed 12 months after surgery. Concurrently, the ferric-reducing antioxidant power assay showed a significant reduction after 6 and 12 months. The level of oxidised glutathione and lipid peroxidation products were increased at 6 months but normalised at 12 months after surgery. As conclusion, a significant weight reduction in obese patients may help to diminish existing DNA damage besides improving many other health aspects in these patients.

DNA damage in obesity: Initiator, promoter and predictor of cancer

Epidemiological evidence linking obesity with increased risk of cancer is steadily growing, although the causative aspects underpinning this association are only partially understood. Obesity leads to a physiological imbalance in the regulation of adipose tissue and its normal functioning, resulting in hyperglycaemia, dyslipidaemia and inflammation. These states promote the generation of oxidative stress, which is exacerbated in obesity by a decline in anti-oxidant defence systems. Oxidative stress can have a marked impact on DNA, producing mutagenic lesions that could prove carcinogenic. Here we review the current evidence for genomic instability, sustained DNA damage and accelerated genome ageing in obesity. We explore the notion of genotoxicity, ensuing from systemic oxidative stress, as a key oncogenic factor in obesity. Finally, we advocate for early, pre-malignant assessment of genome integrity and stability to inform surveillance strategies and interventions.

Application of receiver operating characteristic curve in the assessment of the value of body mass index, waist circumference and percentage of body fat in the Diagnosis of Polycystic Ovary Syndrome in childbearing women

BACKGROUND

There are various parameters to analyze obesity, however, no standard reference to predict, screen or diagnose PCOS with various obesity parameters has been established, and the accuracy of these parameters still needs to be studied.This study was to use the receiver operating characteristic (ROC) curve to explore the different values of three obesity parameters, body mass index (BMI), waist circumference (WC) and percentage of body fat (PBF) in the diagnosis of polycystic ovary syndrome (PCOS) in Chinese childbearing women.

METHODS

Three hundred patients who were diagnosed with PCOS at Center of Reproductive Medicine and Genetics of Peking University First Hospital were enrolled in this study, and 110 healthy age-matched women were enrolled as controls. The characteristics of BMI, WC and PBF in PCOS patients were analyzed.

RESULTS

Compared with the control group, all the three obesity parameters were significantly increased in PCOS group. In terms of ROC area under the curve, WC > PBF > BMI, and they were all significantly different from those of the control. At a cut-off point of 80.5 cm, WC has a sensitivity of 73.6 % and a specificity of 85 % in diagnosis of PCOS; At a cut-off point of 29 %, PBF has a sensitivity of 88.2 % and a specificity of 57.7 % in diagnosis of PCOS; and at a cut-off point of 26.6 kg/m(2), BMI has a sensitivity of 54.5 % and a specificity of 98 % in diagnosis of PCOS.

CONCLUSION

WC, BMI and PBF are valuable in screening and diagnosis of PCOS in Chinese childbearing women. PBF can be used to screen PCOS as it has a better sensitivity, while BMI can be used in the diagnosis of PCOS as it has a better specificity.