Does polycystic ovary syndrome affect cognition? A functional magnetic resonance imaging study exploring working memory

Possible cognition changes in women with polycystic ovary syndrome: a narrative review

Nowadays, polycystic ovary syndrome (PCOS) and cognitive dysfunction are major health problems among female. This narrative review aimed to investigate cognitive dysfunction in female with PCOS. English and Persian articles published in PubMed, Scopus, Web of Science, Google Scholar, PsycINFO, Scientific Information Database, and Cochrane Database of Systematic Reviews until May 2022 were searched. Sixteen studies involving 850 female with PCOS and 974 controls were assessed. In these studies, the association between biochemical factors and symptoms of PCOS and memory, attention, executive functioning, information processing speed, and visuospatial skills was evaluated. The literature review revealed the possible cognitive changes in female with PCOS. This study summarized the different aspects of cognitive function in female with PCOS due to medication, psychological problems (mood disorders caused by disease symptoms and complications), and biochemical markers, such as metabolic and sex hormone abnormalities. Considering the existing scientific gap regarding the possibility of cognitive complications in female with PCOS, further biological studies should be conducted to evaluate the potential mechanisms involved.

Hypothalamic neuroglial plasticity is regulated by anti-Müllerian hormone and disrupted in polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common reproductive-endocrine disorder affecting between 5 and 18% of women worldwide. An elevated frequency of pulsatile luteinizing hormone (LH) secretion and higher serum levels of anti-Müllerian hormone (AMH) are frequently observed in women with PCOS. The origin of these abnormalities is, however, not well understood.

METHODS

We studied brain structure and function in women with and without PCOS using proton magnetic resonance spectroscopy (MRS) and diffusion tensor imaging combined with fiber tractography. Then, using a mouse model of PCOS, we investigated by electron microscopy whether AMH played a role on the regulation of hypothalamic structural plasticity.

FINDINGS

Increased AMH serum levels are associated with increased hypothalamic activity/axonal-glial signalling in PCOS patients. Furthermore, we demonstrate that AMH promotes profound micro-structural changes in the murine hypothalamic median eminence (ME), creating a permissive environment for GnRH secretion. These include the retraction of the processes of specialized AMH-sensitive ependymo-glial cells called tanycytes, allowing more GnRH neuron terminals to approach ME blood capillaries both during the run-up to ovulation and in a mouse model of PCOS.

INTERPRETATION

We uncovered a central function for AMH in the regulation of fertility by remodeling GnRH terminals and their tanycytic sheaths, and provided insights into the pivotal role of the brain in the establishment and maintenance of neuroendocrine dysfunction in PCOS.

FUNDING

INSERM (U1172), European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement n° 725149), CHU de Lille, France (Bonus H).

Review of the effects of polycystic ovary syndrome on Cognition: Looking beyond the androgen hypothesis

Polycystic-ovary syndrome (PCOS) is the most common endocrine disorder affecting women of reproductive age, and many features associated with PCOS - such as elevated androgens, insulin resistance and inflammation - are known to affect cognition. However, effects of PCOS on cognition are not well-understood. Here we review the current literature on PCOS and cognition, note the extent of PCOS symptomatology studied in relation to cognitive outcomes, and identify key research gaps and common methodological concerns. Findings indicate a pattern of worse performance across cognitive domains and brain measures in women with PCOS relative to non-PCOS controls, as well as a lack of evidence for the common assumption that women with PCOS will have higher performance on tasks with a demonstrated male-advantage due to high testosterone levels. We suggest strategies for moving beyond the focus on elevated androgens, in favor of research practices that account for the nuances and heterogeneity of PCOS symptoms.

EEG-ERP Correlates of Cognitive Dysfunction in Polycystic Ovarian Syndrome

Background

Polycystic ovarian syndrome (PCOS) has been shown to affect the psychological and cognitive status of a woman. However, amidst various conflicting reports in this regard, very few studies attempted to assess these aspects objectively using electroencephalography (EEG) and event-related potential (ERP).

Purpose

To assess changes in neurocognitive and psychological parameters of PCOS women without any other comorbidities.

Methods

PCOS women aged 18 years to 35 years, diagnosed from obstetrics and gynecology OPD who are otherwise free of any other comorbidities, were assessed for psychological status (anxiety and depression using the State-Trait Anxiety Inventory and Beck Depression Inventory, respectively). Thereafter, a cognitive assessment was done subjectively by the Montreal Cognitive Assessment (MoCA) questionnaire and objectively by using EEG [absolute and relative power of alpha, beta, and theta waves along with theta/beta ratios (TBR) and theta/alpha ratio (TAR)] and P300 amplitude and latency of ERP during a visual oddball paradigm task in control ( n = 30) and PCOS ( n = 37) subjects.

Results

PCOS women showed significantly higher anxiety and depression scores along with low MoCA scores. Significantly reduced absolute alpha, increased frontal beta, and markedly increased theta (relative) power with increased TAR in the PCOS group were seen. Also, a significant reduction in P300 amplitude with prolonged latency during the visual oddball paradigm task was evident in them.

Conclusion

Reduced alpha and higher theta activity with increased TAR are indicative of poor neural processing ability. Reduced P300 amplitude with more latency also suggests a cognitive decline, which is corroborated by reduced MoCA scores. Our study objectively indicates the presence of subclinical cognitive impairment in PCOS patients even without any comorbidities.

Polycystic Ovary Syndrome Can Lead to Neurocognitive Changes in Female Rats Treated with Letrozole

Background: Polycystic ovary syndrome (PCOS) is a common endocrine disorder in premenopausal women. Brain functions may be affected in PCOS, and studies reported that PCOS patients are at greater risk for developing mental health conditions, including anxiety or depression. Objectives: This study was designed to evaluate the neurocognitive changes in letrozole-induced PCOS model. Methods: Twenty female Wistar rats (eight-week-old; 160 ± 10 g) were divided into two groups. Group one received vehicle only (carboxymethyl cellulose, orally) once daily, and group two received letrozole (1 mg/kg, orally) once daily. Drugs or vehicles were administered for 21 days. Afterward, behavioral tests, including forced swimming test, open field test, and Y-maze alteration task, were performed. Ovaries were removed after behavioral tests and assessed histologically to confirm the induction of PCOS. Results: Animals with PCOS developed depressive-like behaviors compared with control in forced swimming test (P < 0.001). Anxiety-like behaviors were detected in letrozole-induced PCOS group (P < 0.05). Moreover, animals with PCOS exhibited memory impairment in comparison to normal animals in Y-maze memory assessment (P < 0.05). Conclusions: Rats with PCOS showed a neurocognitive decline in the model of letrozole administration. Future studies should be conducted to clarify the exact mechanisms of these changes and possible approaches to restore them.

Sex hormones and cognition in aging

Hormones of the hypothalamic-pituitary-gonadal axis that regulate reproductive function are also potent neurosteriods that have multiple effects on the development, maintenance and function of the brain. There is a growing body of evidence linking sex hormones to cognitive functioning across the lifespan. Both subjective and objective cognitive changes can occur with aging. For women, cognitive complains are commonly associated with the menopause transition-a time of significant hormone flux. Sex differences in neurodegenerative conditions associated with cognitive dysfunction, such as Alzheimer's disease and Parkinson's disease, suggest a potential link between sex hormones and cognitive decline. Evidence for the effects of hormone therapy on cognition is growing, but remains inconclusive. This chapter provides an overview of sex hormones and cognition in association with healthy aging, including a focus on the menopause transition, as well as reviewing findings linking sex hormones to cognitive decline associated with Alzheimer's disease and Parkinson's disease. An overview of hormone therapy and cognition is also provided.

Polycystic Ovary Syndrome and Brain: An Update on Structural and Functional Studies

CONTEXT

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder of women in reproductive age and is associated with reproductive, endocrine, metabolic, cardiovascular, and psychological outcomes. All these disorders are thought to be affected by central mechanisms which could be a major contributor in pathogenesis of PCOS.

EVIDENCE ACQUISITION

This mini-review discusses the relevance of central nervous system imaging modalities in understanding the neuroendocrine origins of PCOS as well as their relevance to understanding its comorbidities.

EVIDENCE SYNTHESIS

Current data suggest that central nervous system plays a key role in development of PCOS. Decreased global and regional brain volumes and altered white matter microstructure in women with PCOS is shown by structural imaging modalities. Functional studies show diminished reward response in corticolimbic areas, brain glucose hypometabolism, and greater opioid receptor availability in reward-related regions in insulin-resistant patients with PCOS. These structural and functional disturbances are associated with nonhomeostatic eating, diminished appetitive responses, as well as cognitive dysfunction and mood disorders in women with PCOS.

CONCLUSION

Structural and functional brain imaging is an emerging modality in understanding pathophysiology of metabolic disorders such as diabetes and obesity as well as PCOS. Neuroimaging can help researchers and clinicians for better understanding the pathophysiology of PCOS and related comorbidities as well as better phenotyping PCOS.

Liraglutide mends cognitive impairment by averting Notch signaling pathway overexpression in a rat model of polycystic ovary syndrome

AIMS

Polycystic ovary syndrome (PCOS), the rifest endocrine disorder in women, is involved in disrupting many metabolic processes. However, the impact of PCOS on cognitive deficits is still uncertain. Recently, Notch signaling pathway was identified as a key modifier in regulating the pathological process in the ovary and various neurodegenerative disorders. Liraglutide has favourable neuroprotective effects that may protect against the possible cognitive dysfunction in PCOS.

MAIN METHODS

PCOS was induced in rats by administrating Letrozole orally for 21 successive days. Then, Liraglutide (LIR) was administered intraperitoneally for 30 days. Memory was examined using Y-maze, novel object recognition (NOR), and Morris water maze (MWM) tests. Western blotting, enzyme immunoassay, and quantitative real-time PCR were used to examine Notch signaling downstream targets, as well as assessing the expression of the components of various pathways cross talked with Notch signaling in memory impairment. Furthermore, histopathological examination was performed to examine neuronal changes.

KEY FINDINGS

Notch signaling was overexpressed in PCOS rats, which increased Aβ aggregation, apoptosis, and neuroinflammation. Additionally, histopathological examination showed neuronal degeneration, which was marked by diminished acetylcholine levels in the PCOS rats' hippocampi. Finally, serum levels of insulin and testosterone were elevated while estradiol was reduced. Treatment with LIR repaired Notch signaling-attributed changes and improved the PCOS-induced memory impairment in rats.

SIGNIFICANCE

The obtained findings confirm that Notch signaling activation in the hippocampus of rats impairs cognitive functions in PCOS, which is mitigated by LIR. Therefore, LIR may offer a novel therapeutic intervention to impede PCOS-induced dementia.

Animal Models to Understand the Etiology and Pathophysiology of Polycystic Ovary Syndrome

More than 1 out of 10 women worldwide are diagnosed with polycystic ovary syndrome (PCOS), the leading cause of female reproductive and metabolic dysfunction. Despite its high prevalence, PCOS and its accompanying morbidities are likely underdiagnosed, averaging > 2 years and 3 physicians before women are diagnosed. Although it has been intensively researched, the underlying cause(s) of PCOS have yet to be defined. In order to understand PCOS pathophysiology, its developmental origins, and how to predict and prevent PCOS onset, there is an urgent need for safe and effective markers and treatments. In this review, we detail which animal models are more suitable for contributing to our understanding of the etiology and pathophysiology of PCOS. We summarize and highlight advantages and limitations of hormonal or genetic manipulation of animal models, as well as of naturally occurring PCOS-like females.

Exploratory study of a screening measure for polycystic ovarian syndrome, quality of life assessment, and neuropsychological evaluation

Background

The universally adopted 2018 PCOS medical diagnostic and treatment guidelines for Polycystic Ovarian Syndrome (PCOS) cites the need for a brief screening measure that can be easily administered in the clinical care setting. We evaluate a 12-item questionnaire emphasizing the medical symptoms of PCOS with a group of women with PCOS as well as comparison samples of college women not diagnosed with PCOS.

Method

Of 120 undergraduate psychology women 18 to 41 years of age, 86 screened negative on a 12-item PCOS symptoms inventory. They were compared to a group of PCOS patients diagnosed medically in a manner consistent with the Teede et al. (2018) evidence-based diagnostic guidelines. The screen-positive, screen-negative, and PCOS-confirmed groups were compared on the PCOS Quality-of-Life (QoL) questionnaire, Zung Self-Rating Depression Scale (ZDS), Spielberg State-Trait Anxiety Inventory (STAI), Fatigue Symptom Inventory (FSI), Spiritual well-being and Spiritual Beliefs Inventories, the computerized Automated Neuropsychological Assessment Metric (ANAM) battery, and an experimental tachistoscopic Bilateral Perceptual Asymmetries Letter and Dots Matching Bilateral Field Advantage (BFA) test (to evaluate the effects of early brain androgenization possible from PCOS). For each questionnaire and neuropsychological performance principal outcome, the Linear Mixed Effects (LME) model was employed to evaluate the predictive significance of demographic characteristics and group membership (confirmed cases, screen negative and screen positive cases) for these outcomes.

Results

The PCOS-confirmed women scored more poorly than the screen-negative (reference) and screen-positive groups on all the measures of physical, emotional, social, and spiritual well-being measures. On the ANAM neuropsychological battery, PCOS-confirmed women did more poorly on Sternberg Memory and Stimulus Response throughput measures. They also had slower correct response speed for both the unilateral and bilateral dot- and letter-matching tachistoscopic stimulus presentations. However, the bilateral field advantage throughput performance ratio did not differ among groups, which is a global measure of bilateral versus unilateral brain/behavior asymmetries.

Conclusion

PCOS screening can be a feasible and important part of women’s healthcare. PCOS-confirmed women should receive not only the medical standard of care from the 2018 guidelines, but also comprehensive psychosocial and neurocognitive support to enhance their quality of life.

Plasma luteinizing hormone level affects the brain activity of patients with polycystic ovary syndrome

OBJECTIVE

Cognitive function has been reported to be impaired in women with polycystic ovary syndrome (PCOS). This study aimed to investigate the effect of PCOS on brain activity and explore the relationship between brain activity and sex hormone levels in women with PCOS (WPCOS).

METHODS

Twenty-one women aged 18-45 years old with new-diagnosed PCOS were enrolled. Plasma levels of six sex hormones including luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were tested during the 2-5 days of their menstrual periods. Twenty-seven healthy controls (HC) were recruited. Every subject underwent a resting-state functional magnetic resonance imaging (fMRI). The amplitude of low-frequency fluctuation (ALFF) of the whole brain was evaluated followed by the functional connectivity (FC) analysis. Finally, the correlation between the ALFF, FC of the significant areas and the plasma hormone levels were analyzed.

RESULTS

The patients showed increased ALFF value in the left inferior temporal gyrus (ITG.L) and decreased ALFF value in the left inferior occipital gyrus (IOG.L) as well as the superior frontal gyrus (SFG.R, P < 0.005). For the FC analysis, patients showed decreased FC in SFG.R with the right middle frontal gyrus (MFG.R, P < 0.05). The FC between SFG.R and MFG.R was negatively correlated with LH level (R=-0.594, P = 0.005) and with the LH/FSH ratio (R=-0.521, P = 0.015).

CONCLUSION

PCOS can induce changes in activities of brain regions responsible for visuospatial working memory, face processing and episodic memory. The reduced functional connectivity within the right frontal lobe is related with the high LH level in WPCOS.

Changes in Resting-State Cerebral Activity in Women With Polycystic Ovary Syndrome: A Functional MR Imaging Study

BACKGROUND

Previous studies have found that women with polycystic ovary syndrome (PCOS) have some degree of brain function change as well as cognitive function and emotions, such as poor executive functioning and memory, anxiety and depressive symptoms. However, the neurobiological mechanisms underlying these alterations have not yet been clarified.

METHOD

Fasting serum hormone testing, neuropsychological testing and resting-state magnetic resonance imaging (rs-fMRI) were performed in 41 women with newly diagnosed PCOS and 41 healthy controls matched by age and education during their 2-5 days of menstrual period. Analysis of the amplitude of low-frequency fluctuation (ALFF) was used to calculate the seed points. Then, the functional connectivity (FC) values between these abnormal seed points and other voxels in the whole brain were calculated. Finally, the correlations among clinical indexes, neuropsychological evaluation scores, and neuroimaging data were analyzed.

RESULTS

Compared with the control group, the PCOS group showed higher luteinizing hormone (LH) and serum insulin levels, worse sleep quality, increased depressive and anxiety state scores, and memory and executive function impairments. Pearson's correlation analysis showed that the decreased ALFF value in the left middle frontal gyrus (MFG.L), which is related to poor executive performance and depressive disorders, was negatively correlated with the plasma insulin level in subjects with insulin resistance. Furthermore, the increased FC strength between the MFG.L and left inferior frontal gyrus (IFG.L) was positively correlated with the serum testosterone level. The enhanced FC strength between the left posterior cingulate gyrus (PCG.L) and triangular part of the left inferior frontal gyrus (IFGtriang.L) was negatively correlated with the plasma LH level. When use the right middle occipital gyrus (MOG.R) as the seed point, the FC strength with the right inferior occipital gyrus (IOG.R), which is associated with impaired memory, was decreased.

CONCLUSION

The ALFF and FC results elucidated brain functional abnormalities at the regional and network levels in women with PCOS, while correlation analyses simultaneously demonstrated that these alterations were associated with serum hormones and cognitive function. These results may provide useful information regarding the potential mechanisms of cognitive impairment and emotional changes in this population.

The impact of sex hormones and metabolic markers on depressive symptoms and cognitive functioning in PCOS patients

The aim of the study was to analyze associations between cognitive deficits and such factors like hormone levels and metabolic risk factors in PCOS women. Fifty-five PCOS patients aged 17-30 underwent analyses for FSH, LH, 17-beta-estradiol, DHEAS, androstenedione, SHBG, lipid profile during the follicular phase. Fasting glucose and insulin concentrations were also measured, as well as their levels after oral-glucose administration. All participants underwent an assessment with: Trail Making Test A and B, Stroop Test, Verbal and Categorical Fluency Test. The intensity of depressive symptoms was measured by the Beck Depression Inventory (BDI). We observed a positive correlation of the depression scores with the OGTT 120' and triglycerides, and a negative correlation of the depression scores with serum HDL. The higher were the insulin levels at 120 min; the more pronounced were the deficits of the verbal psychomotor speed. Higher free testosterone correlated with better verbal psychomotor speed. Androstenedione level was associated with worse scores in executive functions assessment. 17-OH-P levels positively correlated with phonology verbal fluency scores and higher plasma cortisol level at 10 p.m. correlated with worse verbal processing speed. Endocrine and metabolic parameters seem to be important factors mediating cognitive deficits in PCOS.

Dysglycemia, Not Altered Sex Steroid Hormones, Affects Cognitive Function in Polycystic Ovary Syndrome

Context

Polycystic ovary syndrome (PCOS) is a complex endocrine condition characterized by multiple reproductive and metabolic abnormalities. Because individual reproductive and metabolic abnormalities modulate working memory in the general population, there is growing interest in whether cognitive function is dually and negatively affected in PCOS.

Objective

To examine the association of reproductive and metabolic features with cognitive function in women with and without PCOS.

Design

An observational, cross-sectional study was conducted at an academic clinical research center in North America between 2006 and 2009. Common tests of working memory (i.e., manual dexterity, perceptual speed, and visuospatial ability) were performed by women with PCOS (n = 40) and control subjects (n = 40). Markers of sex steroid hormones, ovulatory function, and cardiometabolic health were also assessed.

Results

Reduced visuospatial ability was observed in women with PCOS compared with control subjects (P < 0.01). Reduced visuospatial ability was linked to higher levels of hemoglobin A1c in the entire study cohort, independent of body mass index or PCOS status. No associations were observed between visuospatial ability and reproductive features, after controlling for confounding variables.

Conclusion

Our findings support a role for glycemic control, and not PCOS per se, in cognitive dysfunction in women of reproductive age. Additional studies are needed to understand the short- and long-term effects of dysglycemia on brain health in women with PCOS, given their increased propensity for metabolic comorbidities, compared with control subjects.

Neurosteroid Actions in Memory and Neurologic/Neuropsychiatric Disorders

Memory dysfunction is a symptomatic feature of many neurologic and neuropsychiatric disorders; however, the basic underlying mechanisms of memory and altered states of circuitry function associated with disorders of memory remain a vast unexplored territory. The initial discovery of endogenous neurosteroids triggered a quest to elucidate their role as neuromodulators in normal and diseased brain function. In this review, based on the perspective of our own research, the advances leading to the discovery of positive and negative neurosteroid allosteric modulators of GABA type-A (GABA_A), NMDA, and non-NMDA type glutamate receptors are brought together in a historical and conceptual framework. We extend the analysis toward a state-of-the art view of how neurosteroid modulation of neural circuitry function may affect memory and memory deficits. By aggregating the results from multiple laboratories using both animal models for disease and human clinical research on neuropsychiatric and age-related neurodegenerative disorders, elements of a circuitry level view begins to emerge. Lastly, the effects of both endogenously active and exogenously administered neurosteroids on neural networks across the life span of women and men point to a possible underlying pharmacological connectome by which these neuromodulators might act to modulate memory across diverse altered states of mind.

Sympathovagal imbalance and neurophysiologic cognitive assessment using evoked potentials in polycystic ovary syndrome in young adolescents - a cross-sectional study

Background Altered lifestyle and urbanization have potentially increased the prevalence of polycystic ovary syndrome (PCOS) among the women in India. The aim of the present study was to evaluate the autonomic function and subclinical cognition impairment using evoked potentials in PCOS-affected young adolescents. Methods This was a cross-sectional study, approved by Indian Medical of Council Research as a short-term student project. The study was performed with adolescent girls (age group, 10-18 years) diagnosed as having PCOS, attending the Department of Obstetrics and Gynecology at Sri Manakula Vinayagar Medical College and Hospital, Puducherry. Autonomic function was evaluated using heart rate variability and cognition employing auditory evoked potentials (P300 latency and amplitude) among the control group (n=30) and the PCOS group (n=30). Results Our study reports indicated that autonomic functions were significantly affected among the PCOS group compared to the control group (p=0.03), with sympathetic dominance and decreased vagal tone. P300 latency was prolonged and amplitude was decreased among the PCOS group, but the results were not statistically significant when compared to the control group. Body mass index showed significant correlation with sympathovagal imbalance. Conclusion The study indicates that autonomic functions are significantly altered in the PCOS group. Subclinical cognition impairment is seen among the PCOS group but is not pronounced enough to be proven statistically. This study informs adolescent girls to make early lifestyle changes as soon as possible before any significant clinical impairment occurs.

Polycystic ovary syndrome: Understanding the role of the brain

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder and the leading cause of anovulatory infertility. Characterised by hyperandrogenism, menstrual dysfunction and polycystic ovaries, PCOS is a broad-spectrum disorder unlikely to stem from a single common origin. Although commonly considered an ovarian disease, the brain is now a prime suspect in both the ontogeny and pathology of PCOS. We discuss here the neuroendocrine impairments present in PCOS that implicate involvement of the brain and review evidence gained from pre-clinical models of the syndrome about the specific brain circuitry involved. In particular, we focus on the impact that developmental androgen excess and adult hyperandrogenemia have in programming and regulating brain circuits important in the central regulation of fertility. The studies discussed here provide compelling support for the importance of the brain in PCOS ontogeny and pathophysiology and highlight the need for a better understanding of the underlying mechanisms involved.