Increased risk of fractures in patients with polycystic ovary syndrome: a nationwide population-based retrospective cohort study

Contrasting Bone Profiles in PCOS Are Related to BMI: A Systematic Review and Meta-analysis

CONTEXT

Controversial results have emerged regarding whether polycystic ovary syndrome (PCOS) is protective or increases the risk of bone frailty.

OBJECTIVE

This study investigated whether the PCOS condition affects bone parameters of premenopausal women. This is an update for a previous meta-analysis published in 2019.

DATA SOURCES

We searched MEDLINE and Embase.

STUDY SELECTION

Studies were considered eligible for the update if published in English between October 1, 2018, and December 31, 2023. The diagnosis of PCOS should be based on National Institutes of Health criteria, the Rotterdam Consensus, Androgen Excess & PCOS Society criteria, or International Classification of Diseases codes in women over 18 years old. Only records with the Newcastle-Ottawa Scale ≥ 6 were selected for data extraction.

DATA EXTRACTION

Data were extracted by 2 independent reviewers.

DATA SYNTHESIS

We identified 31 studies that met the inclusion criteria for qualitative analysis from 3322 studies in the whole period (1990-2023). Overall, cross-sectional studies included 1822 individuals with PCOS and 1374 controls, while cohort studies incorporated 30 305 women with PCOS and 10,1907 controls. Contrasting profiles emerged after stratification using a body mass index (BMI) cutoff of 27 kg/m2. Individuals with PCOS and a BMI <27 kg/m2 exhibited lower vertebral and nonvertebral bone density, reduced bone turnover marker (osteocalcin), and increased bone resorption marker (C-terminal type I collagen) levels. Conversely, individuals with PCOS and a BMI ≥27 kg/m2 exhibited increased vertebral and nonvertebral bone mineral density, with no significant changes in bone formation and resorption markers (except osteocalcin).

CONCLUSION

The findings of this study alert for a low bone mass, low bone formation, and increased bone resorption PCOS with a BMI <27 kg/m2.

Bone strength is reduced in a neonatal androgenized rat model

Background

Whether polycystic ovary syndrome (PCOS) affects bone health during a woman's lifespan remains controversial. An androgenized rodent model replicated many metabolic and reproductive features of women with PCOS, and we aimed to use it to investigate the impact of androgens on microarchitecture (by micro-CT), bone mechanical strength, bone formation and resorption markers in rats with intact ovaries (SHAM) who underwent oophorectomy.

Methods

Wistar rats (Rattus norvegicus albinus) were employed for the experiments in this study. The protocol of androgenization consisted of the application of 1.25 mg s.c. testosterone propionate beteween days 2-5 of life, while the controls received the same amount of corn oil s.c. as previously established. Androgenized SHAM rats exhibited chronic anovulation identified by vaginal cytology and a reduction in the proportion of corpus luteum in the ovary in comparison to control SHAM rats. The realization of the ovariectomy or SHAM procedure occurred on Day 100 of life. All groups (n = 8) were followed-up for 180 days to address the study endpoints.

Results

Micro-CT from androgenized female rats (SHAM) showed a divergence between the trabecular and cortical bone profiles. Compared to SHAM controls, these rats had an increase in trabecular bone mass with a diminution in bone resorption C-terminal telopeptide of type 1 collagen (CTX) (p < 0.05), a concomitant decrease in cortical area and thickness in the femur, and a reduction in the strength of the femur on the mechanical test (p < 0.01).

Conclusions

Our results suggest that a reduction in the cortical thickness and cortical area observed in PCOS model rats was associated with a reduced strength of the femur, despite increased trabecular formation. Ovariectomy in the androgenized OVX group limited the progression rate of cortical bone loss, resulting in bone resistance and cortical thickness comparable to those observed in the control OVX group.

Determinants of Bone Mineral Density in Iranian Women with Polycystic Ovary Syndrome

Background

Whether the endocrine aberrations caused by polycystic ovary syndrome (PCOS) might influence bone density in women of reproductive age is controversial.

Objectives

The present study aimed to compare PCOS women to a control group matched in terms of age and body mass index (BMI) regarding bone indices and to clarify the potential relationship between their hormonal changes and bone density.

Methods

This case-control study consisted of 61 PCOS patients, and 35 women with normal ovulatory function served as controls. Bone parameters, including bone mineral content (BMC) and bone mineral density (BMD) in addition to T- and Z-scores, were measured at the lumbar vertebrae, neck of the left femur, hip, and distal part of the radial bone, using dual-energy X-ray absorptiometry. Blood samples were taken to be tested for biochemical parameters and serum concentrations of insulin, osteocalcin, parathyroid hormone (PTH), vitamin D, follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone, dehydroepiandrosterone sulfate (DHEAS), and estradiol were measured. Insulin resistance was evaluated through the homeostatic model assessment of insulin resistance (HOMA-IR).

Results

The results revealed greater levels of HOMA-IR and total testosterone in PCOS women than in controls. Nevertheless, the two groups were comparable in terms of bone parameters. In the control group, BMI was the only determinant of bone density at most of the skeletal sites. Nonetheless, BMI and HOMA-IR were independently and positively associated with bone indices at the femoral neck (FN) and total hip in the PCOS group. Parathyroid hormone and vitamin D concentrations were not different in the two groups. However, phosphate levels were higher in PCOS patients (P = 0.025). Osteocalcin was inversely correlated to BMI, and both groups had a negative correlation between DHEAS and PTH. Serum phosphate was inversely and independently associated with estrogen in the PCOS group (r = -0.377, P = 0.004).

Conclusions

Body mass index and HOMA-IR were independent and positive determinants of FN and total hip bone density in the PCOS subjects. Nonetheless, in the non-PCOS women, BMI was the only independent determinant of bone density at most of the skeletal sites. Additionally, osteocalcin was inversely correlated with BMI in both groups.

Bone health and prevalent fractures in women with polycystic ovary syndrome: a meta-analysis and endocrine-context pathophysiology review

INTRODUCTION

Bone health in those with Polycystic Ovary Syndrome (PCOS) is complex, but the general consensus is that cortical areal bone mineral density (aBMD) sites will be higher in PCOS than in age- and BMI-similar controls. However, spine aBMD sites may be lower, especially in non-obese PCOS. Whether or not incident fracture risk is increased in PCOS is currently controversial; no meta-analysis has yet assessed prevalent fractures.

AREAS COVERED

We assessed the bone effects of PCOS-related ovarian hormone alterations, e.g. androgen excess, tonically normal/higher estradiol, and lower-than-normal progesterone levels. We also highlighted evidence that common PCOS medications (e.g. combined hormonal contraceptives [CHC], metformin, and spironolactone) have important bone effects. In adolescents, meta-analysis of CHC showed significant negative aBMD changes. Inflammation has negative PCOS bone effects and is linked with CHC use.

EXPERT OPINION

Is fracture risk altered by PCOS? Our meta-analysis showed a 25% increased risk of prevalent fracture in PCOS versus controls; this did not reach statistical significance. Future prospective research needs to collect and evaluate ovulation characteristics, progesterone exposure, and adolescent CHC use, in addition to the complex variables that may influence risks for prevalent or incident fragility fractures and/or for cortical and cancellous aBMD values in PCOS.

Effects of distinct Polycystic Ovary Syndrome phenotypes on bone health

Polycystic Ovary Syndrome (PCOS) is a highly prevalent and heterogenous endocrinopathy affecting 5-18% of women. Although its cardinal features include androgen excess, ovulatory dysfunction, and/or polycystic ovarian morphology, women often display related metabolic manifestations, including hyperinsulinaemia, insulin resistance, and obesity. Emerging data reveal that the hormonal alterations associated with PCOS also impact bone metabolism. However, inconsistent evidence exists as to whether PCOS is a bone-protective or bone-hindering disorder with an accumulating body of clinical data indicating that hyperandrogenism, hyperinsulinaemia, insulin resistance, and obesity may have a relative protective influence on bone, whereas chronic low-grade inflammation and vitamin D deficiency may adversely affect bone health. Herein, we provide a comprehensive assessment of the endocrine and metabolic manifestations associated with PCOS and their relative effects on bone metabolism. We focus principally on clinical studies in women investigating their contribution to the alterations in bone turnover markers, bone mineral density, and ultimately fracture risk in PCOS. A thorough understanding in this regard will indicate whether women with PCOS require enhanced surveillance of bone health in routine clinical practice.

Bone Health in Women With Polycystic Ovary Syndrome: A Narrative Review

Bone as an active connective and endocrine tissue is influenced by hormones, physical activity, inflammatory factors, minerals, dietary components, and body weight. Bone fractures are a major cause of decreased quality of life and mortality in humans. Polycystic ovary syndrome (PCOS), is one of the most common endocrine disorders in women of reproductive age worldwide. PCOS is associated with disturbances in androgen and estrogen levels, insulin resistance (IR), obesity, as well as low-grade chronic inflammation, and gut microbiota (GM) dysbiosis, all of which may negatively or positively affect bone metabolism. However, it has not yet been well clarified whether PCOS is bone-protective or bone-destructive. This study aimed to review the association between bone health and PCOS, and summarize its related factors. PubMed, Scopus, and Web of Science databases were searched to retrieve relevant English publications investigating the relationship between bone health and PCOS. Several disorders associated with PCOS can negatively or positively affect bone metabolism. Despite some positive effects of insulin, androgens, estrogens, and obesity on bone, IR, estrogen deficiency, low-grade chronic inflammation, and GM dysbiosis may adversely affect the bone metabolism in PCOS women. Studies comparing bone mineral density or bone metabolism and the risk of bone fractures in women with PCOS have controversial results. Further studies are required to understand the mechanisms underlying bone metabolism in PCOS subjects. Moreover, prospective studies are needed to estimate the risk of bone fractures and osteoporosis in PCOS subjects.

Exploring the relationship between osteoporosis and polycystic ovary syndrome based on bioinformatics

BACKGROUND

In recent years, clinical studies have found that there is a close relationship between osteoporosis and polycystic ovary syndrome. However, there are few literature on the pathogenesis of osteoporosis and polycystic ovary syndrome. In order to clarify their common pathogenic mechanism and provide potential targets for drugs to regulate them at the same time, bioinformatics methods are used to explore, so as to provide a new direction for the study of the relationship between diseases in the future.

METHODS

To screen the targets of osteoporosis and polycystic ovary syndrome by Genecards, Online Mendelian Inheritance in Man databases and Therapeutic Target Database to take the intersection of the two mappings and upload the intersection targets to the STRING database to construct protein-protein interaction network; to screen the core targets by degree value and import them to Metascape database for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis; and finally, to construct the visualization network of core targets and pathways by Cytoscape software. Ethical approval and informed consent of patients are not required because the data used in this study is publicly available and does not involve individual patient data or privacy.

RESULTS

The core targets of polycystic ovary syndrome and osteoporosis were insulin gene, insulin-like growth factor 1, CTNNB1, serine/threonine kinase 1, signal transducer and activator of transcription 3, LEP, etc. The biological processes involved include the regulation of protein phosphorylation, cell proliferation and differentiation, hormone endocrine, reproductive system and skeletal system. The related pathways were concentrated in Foxo signaling pathway, HTLV-I infection, PI3K-AKT signaling pathway, MAPK signaling pathway and AGE-RAGE signaling pathway in diabetic complications.

CONCLUSIONS

There is a close relationship between osteoporosis and polycystic ovary syndrome in terms of target and molecular mechanism. This study used bioinformatics to clarify their targets and mechanisms, providing potential targets for drugs to regulate both diseases simultaneously and providing new directions to explore the relationship between the diseases.

The role of androgens in women's health and wellbeing

Androgens in women, as well as in men, are intrinsic to maintenance of (i) reproductive competency, (ii) cardiac health, (iii) appropriate bone remodeling and mass retention, (iii) muscle tone and mass, and (iv) brain function, in part, through their mitigation of neurodegenerative disease effects. In recognition of the pluripotency of endogenous androgens, exogenous androgens, and selected congeners, have been prescribed off-label for several decades to treat low libido and sexual dysfunction in menopausal women, as well as, to improve physical performance. However, long-term safety and efficacy of androgen administration has yet to be fully elucidated. Side effects often observed include (i) hirsutism, (ii) acne, (iii) deepening of the voice, and (iv) weight gain but are associated most frequently with supra-physiological doses. By contrast, short-term clinical trials suggest that the use of low-dose testosterone therapy in women appears to be effective, safe and economical. There are, however, few clinical studies, which have focused on effects of androgen therapy on pre- and post-menopausal women; moreover, androgen mechanisms of action have not yet been thoroughly explained in these subjects. This review considers clinical effects of androgens on women's health in order to prevent chronic diseases and reduce cancer risk in gynecological tissues.

Vitamin D, Bone Metabolism, and Fracture Risk in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among premenopausal women. PCOS may have reproductive, metabolic, cardiovascular, and psychological implications. Vitamin D deficit is often encountered in PCOS women and may contribute to the pathophysiology of this disorder. As of the key role of vitamin D in bone and mineral metabolism, and because the vitamin D status appears to be closely linked with the PCOS manifestations including insulin resistance, obesity, ovulatory and menstrual irregularities, oxidative stress and PTH elevation, hypovitaminosis D may directly and indirectly via the different facets of PCOS impair bone health in these women. Although limited data are available on life-long fracture risk in women with PCOS, the importance of preserving bone health in youth and adults to prevent osteoporosis and related fractures is also recognized in PCOS women. Evidence of the association between vitamin D and the clinical hallmarks of PCOS are summarized and discussed. Vitamin D arises as a cornerstone in women with PCOS and contributes to the pathophysiological link between PCOS and bone metabolism.

The Relationship Between Polycystic Ovarian Syndrome, Periodontal Disease, and Osteoporosis

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder to affect women in their reproductive years. There has been growing concern that women with PCOS may suffer from long-term metabolic consequences due to the high degree of insulin resistance that is often present in PCOS. However, few longitudinal studies exist in this area and there is a paucity of data on whether women with PCOS are at risk of other chronic diseases as they age. Specifically, current evidence suggests that reproductive-age women with PCOS may be at increased risk for both osteoporosis and periodontal disease (PD)-both these chronic diseases can have serious implications for health and quality of life. However, few studies have addressed how risk factors for osteoporosis and PD may be altered by aging in PCOS. The PCOS phenotype of women beyond reproductive years is poorly understood, and it is not known whether the metabolic profile of older women with PCOS results in an increased risk of osteoporosis and PD. The objective of this review is to discuss the relationships between PCOS, osteoporosis, and PD, and how these relationships could be impacted during aging. The long-term goal of this review is to provide direction for future research that is needed to more clearly elucidate these relationships and eventually provide a basis for evidence-based health recommendations.

Negative impact of polycystic ovary syndrome on bone health: a systematic review and meta-analysis

BACKGROUND

Polycystic ovary syndrome (PCOS) has reproductive and metabolic aspects that may affect bone health. Controversial results from different studies regarding the risk of fractures, bone mineral density (BMD) or bone markers led to uncertainty whether PCOS might improve or deteriorate bone health.

OBJECTIVE AND RATIONALE

This study aimed to investigate the impact of PCOS on bone markers, BMD and fracture risk.

SEARCH METHODS

A systematic review and a meta-analysis were carried out. PubMed, EMBASE and Cochrane databases were searched for eligible studies from 1st of January of 1990 to 9th of October of 2018. Eligible studies enrolled women older than 18 years with PCOS, which should be diagnosed according to the Rotterdam Consensus, the Androgen Excess Society, the National Institutes of Health Consensus or the International Classification of Diseases. The studies were grouped according to patient mean BMI: <27 kg/m2 or ≥27 kg/m2. The results were polled as mean difference (MD), standardized MD (SMD) and hazard ratio (HR).

OUTCOMES

Overall, 921 studies were retrieved, and 31 duplicated studies were removed. After screening the titles and abstracts, 80 studies were eligible for full text reading. Of those, 23 studies remained for qualitative synthesis. With the exception of one study, all studies were considered high quality based on the Newcastle-Ottawa scale (NOS; score ≥6). Meta-analysis was performed in 21 studies, with a total of 31 383 women with PCOS and 102 797 controls. Women with PCOS with BMI <27 kg/m2 had lower BMD of the total femur (MD, -0.04; 95% CI, -0.07 to 0.00; I2 = 31%; P = 0.22) and spine (MD, -0.07; 95% CI, -0.13 to -0.01; I2 = 70%; P < 0.01) when compared with the control group, whereas for women with BMI ≥27 kg/m2 no difference was observed (femur: MD, 0.02; 95% CI, -0.02 to 0.05; I2 = 20%, P = 0.29; spine: MD, 0.02; 95% CI, -0.06 to 0.05; I2 = 0%; P = 0.84). Osteocalcin was remarkably reduced in women with PCOS with BMI <27 kg/m2 (SMD, -2.68; 95% CI, -4.70 to -0.67; I2 = 98%; P < 0.01), but in women with BMI ≥27 kg/m2, there were no differences between PCOS and controls. Few studies (n = 3) addressed the incidence of bone fractures in women with PCOS. The HR for total bone fractures did not identify differences between women with PCOS and controls.

WIDER IMPLICATIONS

On the basis of the available evidence, it is possible to assume that PCOS in women with BMI <27 kg/m2 is associated with reduced BMD in the spine and femur, and decreased bone formation, as manifested by lower levels of circulating osteocalcin. These findings suggest that bone parameters in PCOS may be linked, to some extent, to adiposity. These studies included premenopausal women, who have already achieved peak bone mass. Hence, further prospective studies are necessary to clarify the existence of increased risk of fractures in women with PCOS.

Androgens and Androgen Receptor Actions on Bone Health and Disease: From Androgen Deficiency to Androgen Therapy

Androgens are not only essential for bone development but for the maintenance of bone mass. Therefore, conditions with androgen deficiency, such as male hypogonadism, androgen-insensitive syndromes, and prostate cancer with androgen deprivation therapy are strongly associated with bone loss and increased fracture risk. Here we summarize the skeletal effects of androgens—androgen receptors (AR) actions based on in vitro and in vivo studies from animals and humans, and discuss bone loss due to androgens/AR deficiency to clarify the molecular basis for the anabolic action of androgens and AR in bone homeostasis and unravel the functions of androgen/AR signaling in healthy and disease states. Moreover, we provide evidence for the skeletal benefits of androgen therapy and elucidate why androgens are more beneficial than male sexual hormones, highlighting their therapeutic potential as osteoanabolic steroids in improving bone fracture repair. Finally, the application of selective androgen receptor modulators may provide new approaches for the treatment of osteoporosis and fractures as well as building stronger bones in diseases dependent on androgens/AR status.