Objectives(1) To establish the prevalence of sleep disorders in women with PCOS. (2) To establish the association between sleep disturbance and cardiovascular risk factors in women with PCOS.MethodsThe electronic databases PubMed and EMBASE were searched for observational studies of individuals with PCOS published in English from inception to 21 October 2021. The dichotomous outcome measure was presented as odds ratio (OR) and 95% confidence interval (CI). The mean difference (MD) in continuous variables was expressed for each study.ResultsA total of 18 articles were included in this meta-analysis, with a total of 16,152 participants from nine different countries. Women with PCOS had a high prevalence of sleep disturbance (OR = 6.22; 95% CI: 2.77, 13.97; p < 0.001), higher PSQI scores (MD = 2.10; 95% CI: 0.29, 3.90; p = 0.02), and shorter duration of sleep (MD = −15.65 min; 95% CI: −27.18, −4.13; p = 0.008). We found that body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), low-density lipoprotein cholesterol (LDL-c), fasting glucose, 2-h glucose, and waist circumference (WC) levels were significantly higher and high-density lipoprotein cholesterol (HDL-c) was significantly lower in PCOS with sleep disturbance than in PCOS without sleep disturbance.ConclusionsThe current study shows a high prevalence of sleep disturbance in women with PCOS and provides evidence of an association between cardiovascular risk factors and sleep disturbance among this population. Increased attention should be paid to sleep management in clinical guidelines for PCOS.Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022298040.

ObjectivesPolycystic ovary syndrome (PCOS) is one of the most common endocrinopathy disorders in premenopausal women, which is characterized by hyperandrogenemia, anovulation, and polycystic ovarian morphology (PCOM). Time-restricted feeding (TRF) is a new intermittent restriction dietary pattern, which has been shown to have positive benefits on obesity and glycolipid metabolism disorders. We aimed to explore the effect of the feeding regimen (ad libitum vs. TRF) on the glycolipid metabolism and reproductive endocrine disorders in a PCOS mouse model.MethodsPCOS mouse model was induced by continuous subcutaneous administration of dihydrotestosterone for 21 days. Mice were fed a high-fat diet (HFD) for 8 weeks on an ad libitum or time- restricted diet (from 10:30 p.m. to 6:30 a.m.).ResultsCompared to control mice, PCOS mice that received TRF treatment had significantly lower body weight, reduced adiposity, lower area under the curve (AUC) of glucose response in the oral glucose tolerance test (OGTT), and lower AUC in the insulin tolerance test (ITT). TRF also ameliorated lipid metabolism, as shown by a reduction in plasma lipid profiles (triglycerides and cholesterol) and the triglyceride content in the liver of PCOS mice. In terms of reproduction, the plasma androgen level, plasma estrogen (E2) level, and luteinizing hormone (LH)/follicle stimulating hormone (FSH) ratio in PCOS mice were significantly reduced after 8 weeks of TRF treatment. In addition, ovarian histology showed that TRF inhibits cyst formation and promotes corpus luteum formation.ConclusionIn conclusion, TRF improved metabolic and endocrine profiles in mice with PCOS.

STUDY QUESTION What is the association between late bedtime, night sleep duration, and lifetime cardiovascular disease (CVD) risk in women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER Both late bedtime (≥1:00) and short sleep duration (<7 h/night) were independently associated with a high-lifetime CVD risk among women with PCOS. WHAT IS KNOWN ALREADY Previous studies indicated that sleep disturbances, including altered sleep duration and staying up late (SUL), occurred more frequently among women with PCOS compared to women without PCOS. Studies have shown that both PCOS and sleep disturbances are associated with deterioration in cardiometabolic health in the longer term. However, there are limited data regarding the possible association between sleep disturbances and CVD risk among reproductive-aged women with PCOS. STUDY DESIGN, SIZE, DURATION From the original 393 women identified at our center, a total of 213 women with PCOS aged 18–40 years were enrolled in a cross-sectional study between March 2020 and July 2022. PARTICIPANTS/MATERIALS, SETTING, METHODS Bedtime and night sleep duration were obtained from a standardized self-administered questionnaire. The prediction for atherosclerotic CVD risk in the China risk model was applied to estimate the lifetime CVD risk in the PCOS population. Restricted cubic spline regression was applied to explore the non-linear association between sleep duration and lifetime CVD risk in a series of models. Multivariable logistic regression analyses were performed to determine the association between bedtime, night sleep duration, and lifetime CVD risk. MAIN RESULTS AND THE ROLE OF CHANCE In our study, we found that the proportion of SUL was 94.25% and the mean (±SD) of night sleep duration was 7.5 ± 1.1 h in women with PCOS. Restricted cubic spline regression analysis showed a U-shaped relation between sleep duration and lifetime CVD risk. After adjusting for occasional drinking, fasting insulin, triglyceride, low-density lipoprotein cholesterol, and testosterone in multivariable logistic analyses, compared with going to bed at 23–24 o’clock, those who went to bed after 1 o’clock were independently associated with high-lifetime CVD risk [odds ratio (OR) = 3.87, 95% CI: 1.56–9.62]; compared with optimal sleep duration (7–8 h/night), short sleep (<7 h/night) was also independently associated with high-lifetime CVD risk (OR = 2.46, 95% CI: 1.01–5.97). LIMITATIONS, REASONS FOR CAUTION Inferring causality is limited owing to the cross-sectional design. All sleep variables data were obtained from a standardized self-administered questionnaire rather than measurements using objective approaches. Even after adjusting for potential confounders, we still cannot completely rule out the possibility of residual confounding from unmeasured factors such as socioeconomic status. Future studies with larger sample sizes are needed to further explore the relation between long sleep duration and lifetime CVD risk. Although these findings are not generalizable to non-SUL PCOS populations, they could be used for guiding multidimensional treatment. Lastly, there is no non-PCOS group in the current cross-sectional study, which limits the interpretation of the findings from the PCOS group. WIDER IMPLICATIONS OF THE FINDINGS This is the first study to report that both late bedtime (≥1:00) and short sleep duration (<7 h/night) were independently associated with a high-lifetime CVD risk among reproductive-aged women with PCOS, in a sample of Chinese adults. Predicting cardiovascular risk and examining the association between sleep disturbances and predicted CVD risk among women with PCOS help to highlight the need for early interventions on sleep to improve their cardiovascular outcomes. STUDY FUNDING/COMPETING INTEREST(S) This study was funded by the Natural Science Foundation of Fujian Province (No. 2020J011242), the Fujian provincial health technology project (No. 2022CXB016), the Joint Research Projects of Health and Education Commission of Fujian Province (No. 2019-WJ-39), and the Medical and Health project of Xiamen Science & Technology Bureau (No. 3502Z20214ZD1001). The authors declare that they have no conflict of interest. TRIAL REGISTRATION NUMBER N/A.