Is cardiorespiratory fitness impaired in PCOS women? A review of the literature

Health-related physical fitness in women with polycystic ovary syndrome versus controls: a systematic review and meta-analysis

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a common endocrinopathy associated with cardiometabolic dysfunction.

PURPOSE

(1) To compare HRPF indices, including cardiorespiratory fitness (CRF), muscle strength, and muscle endurance, between women with and without PCOS (i.e., controls). (2) To explore the impact of moderating factors, i.e., insulin sensitivity, androgen levels, physical activity levels, and body mass index, on these indices.

METHODS

Articles comparing HRPF between PCOS and control groups were identified until February 27th, 2022. Random-effects meta-analyses were conducted and moderating factors were explored with subgroup and meta-regression analyses.

RESULTS

Twenty studies were included. Compared to controls, CRF was lower in women with PCOS (n = 15, - 0.70 [- 1.35, - 0.05], P = 0.03, I2 = 95%). Meta-regression analyses demonstrated that fasting insulin (P = 0.004) and homeostatic model assessment of insulin resistance (P = 0.006) were negatively associated with CRF, while sex-hormone binding globulin levels (P = 0.003) were positively associated. Absolute muscle strength was not different between PCOS and controls (n = 7, 0.17 [- 0.10, 0.45], P = 0.22, I2 = 37%). One study evaluated muscle endurance and reported lower core endurance in PCOS subjects compared to controls.

CONCLUSION

These data suggest that PCOS may be associated with impaired CRF. It remains unclear whether muscle strength and endurance differ between women with PCOS and controls. As this data set was limited by a small sample size, potential for bias, and inconsistent findings, additional studies accounting for the heterogeneous presentation of PCOS as well as improved matching between PCOS and controls for characteristics known to affect HRPF would help elucidate the impact of PCOS on indices of HRPF.

PROSPERO REGISTRATION NUMBER

CRD42020196380.

The Effect of Tailored Short Message Service (SMS) on Physical Activity: Results from a Three-Component Randomized Controlled Lifestyle Intervention in Women with PCOS

This analysis of secondary outcome measures of a randomized controlled trial was conducted to study the effect of a one-year three-component (cognitive behavioural therapy, diet, exercise) lifestyle intervention (LSI), with or without additional Short Message Service (SMS) support, on physical activity and aerobic capacity in overweight or obese women with polycystic ovary syndrome (PCOS). Women diagnosed with PCOS and a BMI > 25 kg/m² were randomly assigned to LSI with SMS support (SMS+, n = 60), LSI without SMS support (SMS-, n = 63) or care as usual (CAU, n = 60) in order to lose weight. Based on results from the International Physical Activity Questionnaire (IPAQ), we found a significant within-group increase after one year for SMS+ in the high physical activity category (+31%, p < 0.01) and sitting behaviour decreased (Δ -871 min/week, p < 0.01). Moreover, the peak cycle ergometer workload increased within SMS+ (Δ +10 watts, p < 0.01). The SMS+ group also demonstrated a significantly different increase in walking metabolic equivalent of task minutes (METmin)/week compared with CAU after one year (Δ 1106 METmin/week, p < 0.05). Apart from this increase in walking activity, no other between-group differences were found in this trial. Overall, based on within-group results, SMS support seemed to help with improving physical activity and aerobic capacity and decreasing sedentary behaviour.

Time to Load Up-Resistance Training Can Improve the Health of Women with Polycystic Ovary Syndrome (PCOS): A Scoping Review

BACKGROUND

Guidelines for the management of polycystic ovary syndrome (PCOS) focus on lifestyle changes, incorporating exercise. Whilst evidence suggests that aerobic exercise may be beneficial, less is known about the effectiveness of resistance training (RT), which may be more feasible for those that have low fitness levels and/or are unable to tolerate/participate in aerobic exercise.

OBJECTIVES

To identify the available evidence on RT in women with PCOS and to summarise findings in the context of a scoping review.

ELIGIBILITY CRITERIA

Studies utilising pre-post designs to assess the effectiveness of RT in PCOS; all outcomes were included.

SOURCES OF EVIDENCE

Four databases (PubMed, CENTRAL, CINAHL and SportDiscus) were searched and supplemented by hand searching of relevant papers/reference lists.

CHARTING METHODS

Extracted data were presented in tables and qualitatively synthesised.

RESULTS

Searches returned 42 papers; of those, 12 papers were included, relating to six studies/trials. Statistical changes were reported for multiple pertinent outcomes relating to metabolic (i.e., glycaemia and fat-free mass) and hormonal (i.e., testosterone and sex hormone-binding globulin) profiles.

CONCLUSIONS

There is a striking lack of studies in this field and, despite the reported statistical significance for many outcomes, the documented magnitude of changes are small and the quality of the evidence questionable. This highlights an unmet need for rigorously designed/reported and sufficiently powered trials.

Do Androgenic Pattern, Insulin State and Growth Hormone Affect Cardiorespiratory Fitness and Strength in Young Women with PCOS?

In this study, cardiorespiratory fitness (CRF) and strength level were assessed in women with and without polycystic ovary syndrome (PCOS), matched for age, body composition, androgenic pattern and insulinemic pattern. Patients with and without PCOS were evaluated at the Endocrinology Unit and Sport Medicine Division to assess endocrinological (insulinemic, androgenic pattern and growth hormone), anthropometric (with DEXA) and functional parameters (with cardiopulmonary exercise test and handgrip test), as well as physical activity level (with the Global Physical Activity Questionnaire). A total of 31 patients with PCOS and 13 controls were included. No statistically significant differences were found between groups in terms of age, body mass index, body composition, androgenic pattern, insulin state, growth hormone and physical activity level. The PCOS group demonstrated significantly better cardiorespiratory fitness (VO₂max per kg (30.9 ± 7.6 vs. 24.8 ± 4.1 mL/kg/min; p = 0.010), VO₂max per kg of fat-free mass (52.4 ± 8.9 vs. 45.3 ± 6.2 mL/kg/min; p = 0.018)), strength levels (handgrip per kg (0.36 ± 0.09 vs. 0.30 ± 0.08; p = 0.009), handgrip per kg of fat-free mass (13.03 ± 2.32 vs. 11.50 ± 1.91; p = 0.001)) and exercise capacity (METs at test (14.4 ± 2.72 vs. 12.5 ± 1.72 METs; p = 0.019)). In this study, women with PCOS showed a better cardiorespiratory fitness and strength than the control group. The only determinant that could explain the differences observed seems to be the presence of the syndrome itself. These results suggest that PCOS per se does not limit exercise capacity and does not exclude good functional capacity.

The Effect of Exercise on Cardiometabolic Risk Factors in Women with Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

Background: Polycystic Ovary Syndrome (PCOS), a common endocrine disorder in women of reproductive age, increases the risk for cardiometabolic morbidity. While regular exercise is effective in reducing cardiometabolic risk, women with PCOS may experience condition-specific barriers to exercise thereby limiting its efficacy. Aim: To determine the effect of exercise on cardiometabolic risk factors in women with PCOS. Methods: Five databases (Cochrane, EMBASE, Medline, Scopus and SPORTDiscus) were searched up to December of 2021. Eligible studies included: a randomised controlled design; participants with a diagnosis of PCOS; aerobic and/or resistance exercise intervention lasting ≥4 weeks; cardiometabolic outcomes. Meta-analyses were performed to determine the effect of exercise versus non-exercising control on cardiometabolic outcomes. Results: Of the 4517 studies screened, 18 studies were analysed involving 593 participants. When compared with control, exercise significantly improved cardiorespiratory fitness (weighted mean difference {WMD} = 4.00 mL/kg/min, 95% CI: 2.61 to 5.40, p < 0.001) and waist circumference (WMD = −1.48 cm, 95% CI: −2.35 to −0.62, p = 0.001). Systolic blood pressure, fasting blood glucose, insulin resistance, and lipid profiles remained unchanged. Conclusions: Regular exercise may improve cardiorespiratory fitness and waist circumference in women with PCOS. Further large-scale studies are required to determine whether exercise interventions improve various biochemical and anthropometric parameters in women with PCOS and more severe cardiometabolic abnormalities.

Improvement of anti-Müllerian hormone and oxidative stress through regular exercise in Chinese women with polycystic ovary syndrome

PURPOSE

Structured exercise is shown to be one of the most effective lifestyle interventions for women with polycystic ovary syndrome (PCOS). Anti-Müllerian hormone (AMH) has been proposed as a marker of ovarian dysfunction, and oxidative stress plays an important role in the development of PCOS. We sought to investigate whether there was any effect of aerobic exercise on AMH levels and oxidative stress in Chinese PCOS women.

METHODS

Thirty-eight PCOS women were enrolled and divided into two groups. The exercise group carried out a 12-week exercise program, while the control group maintained their normal lifestyle. All women underwent blood tests and cardiopulmonary exercise tests (CPETs) at enrollment and at 12-week follow-up.

RESULTS

At baseline, there was no statistically significant difference between the two groups in clinical characteristics, AMH, oxidative biomarkers, and CPET parameters. After 12 weeks, body mass index (BMI) and cardiovascular fitness indexes of the exercise group were improved. We also found a decrease in AMH (P = 0.021) and malondialdehyde (MDA) (P = 0.002) and an increase in superoxide dismutase (SOD) (P = 0.009) and total antioxidant capacity (TAC) (P = 0.012) in the exercise group, while there was no change in the control group. Moreover, the change of AMH was positively associated with the change of MDA (r = 0.23, P = 0.003) in the exercise group.

CONCLUSIONS

Our findings demonstrated that 12 weeks of aerobic exercise produced beneficial effects on BMI, cardiovascular fitness, AMH, and oxidative stress in PCOS women. Favorable modification of oxidative stress might thus be an effective method for improvement of AMH in these women, which deserves further exploration in the future.

Association of Angiotensin-Converting Enzyme gene polymorphism in Pakistani women with the atypical steroidogenesis in Polycystic ovarian syndrome: A case-control study

Background

Polymorphism in the angiotensin-converting enzyme gene (ACE) is responsible for elevated ACE concentrations in plasma. High ACE levels induce insulin resistance and hyperandrogenism, which are the main attributes of polycystic ovary syndrome (PCOS). Therefore, it was hypothesized that I/D polymorphism plays a role in the pathogenesis of PCOS.

Objective

A case-control study was designed to investigate the association of I/D polymorphism of the ACE gene with PCOS in Pakistani women of reproductive age.

Methods

ACE I/D polymorphism was assessed in 252 women of age group 16–40 years. For genotypic analysis, PCR amplification of genomic DNA was carried out. Statistical analysis was performed to interpret the results using SPSS software.

Results

Our study showed that PCOS women were more likely to have a high body mass index and waist circumferences. Most PCOS patients had menstrual irregularities 99.3%, hirsutism 75.2% and cysts in ovaries 66.6%, along with other hyperandrogenic conditions (P-value = 0.001). The genotypic and allelic frequencies were significantly different between patients and controls. There was a significant association of three genotypes with the ratio of LH: FSH among PCOS patients (P = 0.05). Anthropometric characters, comorbidities, clinical symptoms, and PCOS conditions showed no statistical significance with ACE polymorphism.

Conclusions

ACE I/D polymorphism was not found associated with clinical conditions of PCOS in women of reproductive age. However, it was associated with atypical steroidogenesis. So, it indicates that ACE I/D polymorphism aggravates the pathogenesis of PCOS.

Association of SOD2 A16V and PON2 S311C polymorphisms with polycystic ovary syndrome in Chinese women

PURPOSE

To investigate the relationship between superoxide dismutase 2 (SOD2) A16V and paraoxonase 2 (PON2) S311C gene variants and the risk of polycystic ovary syndrome (PCOS) and evaluate the effects of the genotypes on clinical, hormonal, metabolic and oxidative stress indexes in Chinese women.

METHODS

This is a cross-sectional study of 932 patients with PCOS and 745 control women. For the clinical and metabolic association study of genotypes, 631 patients and 492 controls were included after excluding the subjects with interferential factors. Genotypes were determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis. Serum total oxidant status, total antioxidant capacity (T-AOC), oxidative stress index and malondialdehyde (MDA) levels, and clinical and metabolic parameters were also analyzed.

RESULTS

The prevalence of the A allele of SOD2 A16V polymorphism was significantly greater in patients with PCOS than in control subjects. Genotype (AA + AV) remained a significant predictor for PCOS in prognostic models including age, body mass index, insulin resistance index, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides (TGs) as covariates. Patients carrying the A allele had significantly higher serum luteinizing hormone (LH) levels, and the ratio of LH to follicle-stimulating hormone compared with patients with the VV genotype. We also showed that patients carrying the C allele of the PON2 S311C polymorphism had lower T-AOC compared with patients carrying the SS genotype. However, no significant differences were observed in the frequencies of the S311C genotypes and alleles of the PON2 gene between PCOS and control groups.

CONCLUSION

The SOD2 A16V, but not PON2 S311C, polymorphism may be one of the genetic determinants for PCOS in Chinese women.

High copper levels in follicular fluid affect follicle development in polycystic ovary syndrome patients: Population-based and in vitro studies

Although the adverse effects of copper overexposure on the liver, kidney, spleen and intestinal organs are well known, information about the impact of copper toxicity on human reproduction is limited. A total of 348 infertile patients were enrolled in our present study, including 89 with polycystic ovary syndrome (PCOS), 145 with fallopian tube obstruction and 114 controls. The follicular fluid concentrations of 22 trace elements were measured by inductively coupled plasma mass spectrometry (ICP-MS). Principal component analysis was used to identify trace element profile alterations in different groups. The mRNA levels of steroidogenesis-related genes were measured by real-time PCR. Our results showed that the trace element profile in follicular fluid was obviously altered in PCOS patients. Copper concentrations were significantly (p < .05) higher in the PCOS group than in the other two groups. Increased copper levels in follicular fluid were associated with a higher number of retrievable oocytes in the PCOS group (B = 1.785, p = .001) but a lower rate of high-quality embryos (B = -6.360, p = .050). Moreover, follicular fluid copper levels were positively correlated with follicular fluid progesterone levels (r = 0.275, p = .010) and testosterone levels (r = 0.250, p = .022). Cultured human granulosa cells overexposed to copper showed significantly (p < .05) increased estradiol secretion and decreased testosterone levels. Real-time quantitative PCR revealed a significant (p < .05) increase in CYP19A1 and HSD3b mRNA expression. Our results indicate that increased copper levels in follicular fluid could affect follicle development in PCOS patients, and the mechanism may be related to copper-induced abnormalities in steroidogenesis.

Exercise, or exercise and diet for the management of polycystic ovary syndrome: a systematic review and meta-analysis

BACKGROUND

Typically, management of PCOS focuses on lifestyle changes (exercise and diet), aiming to alleviate symptoms, and lower the associated risk of type 2 diabetes and cardiovascular disease. Our objective was to analyse evidence on the effectiveness of exercise in the management of PCOS, when compared to (i) usual care, (ii) diet alone, and (iii) exercise combined with diet, and also exercise combined with diet, compared to (i) control or usual care and (ii) diet alone.

METHODS

Relevant databases were searched (June 2017) with no time limit for trial inclusion. Eligible trials employed a randomised or quasi-randomised design to measure the chronic effects of exercise, or exercise and diet in women with PCOS.

RESULTS

Searches returned 2390 articles; of those, 27 papers from 18 trials were included. Results are presented as mean difference (MD) and 95% confidence intervals (95% CI). Compared with control, exercise had a statistical effect on change from baseline fasting insulin (MD - 2.44 μIU/mL, 95% CIs - 4.24 to - 0.64; very low-quality evidence), HOMA-IR (- 0.57, - 0.99 to - 0.14; very low-quality evidence), total cholesterol (- 5.88 mg/dL, - 9.92 to - 1.83; low-quality evidence), LDL cholesterol (- 7.39 mg/dL, - 9.83 to - 4.95; low-quality evidence), and triglycerides (- 4.78 mg/dL, - 7.52 to - 2.05; low-quality evidence). Exercise also improved VO₂ max (3.84 ml/kg/min, 2.87 to 4.81), waist circumference (- 2.62 cm, - 4.13 to - 1.11), and body fat percentage (- 1.39%, - 2.61 to - 0.18) when compared with usual care. No effect was found for change value systolic/diastolic blood pressure, fasting glucose, HDL cholesterol (all low-quality evidence), or waist-to-hip ratio. Many favourable change score findings were supported by post-intervention value analyses: fasting insulin (- 2.11 μIU/mL, - 3.49 to - 0.73), total cholesterol (- 6.66 mg/dL, - 11.14 to - 2.17), LDL cholesterol (- 6.91 mg/dL, - 12.02 to - 1.80), and VO₂ max (5.01 ml/kg/min, 3.48 to 6.54). Statistically lower BMI (- 1.02 kg/m², - 1.81 to - 0.23) and resting heart rate (- 3.26 beats/min - 4.93 to - 1.59) were also revealed in post-intervention analysis. Subgroup analyses revealed the greatest improvements in overweight/obese participants, and more outcomes improved when interventions were supervised, aerobic in nature, or of a shorter duration. Based on limited data, we found no differences for any outcome between the effects of exercise and diet combined, and diet alone. It was not possible to compare exercise vs diet or exercise and diet combined vs diet.

CONCLUSION

Statistically beneficial effects of exercise were found for a range of metabolic, anthropometric, and cardiorespiratory fitness-related outcomes. However, caution should be adopted when interpreting these findings since many outcomes present modest effects and wide CIs, and statistical effects in many analyses are sensitive to the addition/removal of individual trials. Future work should focus on rigorously designed, well-reported trials that make comparisons involving both exercise and diet.

SYSTEMATIC REVIEW REGISTRATION

This systematic review was prospectively registered on the Prospero International Prospective Register of Systematic Reviews ( CRD42017062576 ).

The effect of vitamin D supplementation in combination with low-calorie diet on anthropometric indices and androgen hormones in women with polycystic ovary syndrome: a double-blind, randomized, placebo-controlled trial

PURPOSE

Polycystic ovary syndrome (PCOS) is known as the most common endocrine disorder in reproductive age women. The aim of this studywas to evaluate the effects of vitamin D supplementation in combination with low-calorie diet on anthropometric indices, reproductive hormones and menstrual regularity in overweight and obese PCOS women.

METHODS

In this randomized controlled clinical trial, 60 PCOS women with vitamin D insufficiency were randomly assigned to 12 weeks of either (1) weight-loss intervention + 50,000 IU/week oral vitamin D3 or (2) weight-loss intervention + placebo. At the beginning and end of the study, the anthropometric indices, body composition, 25-hydroxyvitamin D, total testosterone, dehydroepiandrosterone sulfate (DHEAS), sex hormone-binding globulin (SHBG) and free androgen index (FAI) were measured and regularity of menses was compared among the two groups.

RESULT

After 12-week intervention, median of serum 25-hydroxyvitamin D3 significantly increased from 18.5 (10.75-20) ng/ml to 42.69 (34-53.25) ng/ml in vitamin D group compared to placebo group (p < 001). Moreover, there was a significant improvement in frequency regular menstrual cycle (p = 0.01). Mean of weight, body mass index, fat mass, waist and hip circumference and waist-to-hip ratio significantly decreased in both groups, but was not different between two groups. Mean of total testosterone insignificantly decreased from 0.7 to 0.5 ng/ml in vitamin D group (p = 0.18). In addition, we did not observe significant differences regarding DHEAS, FAI and SHBG between two groups.

CONCLUSIONS

In women with PCOS, androgen profile did not change with vitamin D supplementation when combined with low-calorie diet, but menstrual frequency significantly improved.

CLINICAL TRIAL REGISTRATION NUMBER

IRCT2016062710826N19.