Bulent O. Yildiz
Hacettepe University
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Featured researches published by Bulent O. Yildiz.
Nature Reviews Disease Primers | 2007
Ricardo Azziz; Enrico Carmina; Zi-Jiang Chen; Andrea Dunaif; Joop S.E. Laven; Richard S. Legro; Daria Lizneva; Barbara Natterson-Horowtiz; Helena Teede; Bulent O. Yildiz
Polycystic ovary syndrome (PCOS) affects 5-20% of women of reproductive age worldwide. The condition is characterized by hyperandrogenism, ovulatory dysfunction and polycystic ovarian morphology (PCOM) - with excessive androgen production by the ovaries being a key feature of PCOS. Metabolic dysfunction characterized by insulin resistance and compensatory hyperinsulinaemia is evident in the vast majority of affected individuals. PCOS increases the risk for type 2 diabetes mellitus, gestational diabetes and other pregnancy-related complications, venous thromboembolism, cerebrovascular and cardiovascular events and endometrial cancer. PCOS is a diagnosis of exclusion, based primarily on the presence of hyperandrogenism, ovulatory dysfunction and PCOM. Treatment should be tailored to the complaints and needs of the patient and involves targeting metabolic abnormalities through lifestyle changes, medication and potentially surgery for the prevention and management of excess weight, androgen suppression and/or blockade, endometrial protection, reproductive therapy and the detection and treatment of psychological features. This Primer summarizes the current state of knowledge regarding the epidemiology, mechanisms and pathophysiology, diagnosis, screening and prevention, management and future investigational directions of the disorder.Polycystic ovary syndrome (PCOS) affects 5–20% of women of reproductive age worldwide. The condition is characterized by hyperandrogenism, ovulatory dysfunction and polycystic ovarian morphology (PCOM) — with excessive androgen production by the ovaries being a key feature of PCOS. Metabolic dysfunction characterized by insulin resistance and compensatory hyperinsulinaemia is evident in the vast majority of affected individuals. PCOS increases the risk for type 2 diabetes mellitus, gestational diabetes and other pregnancy-related complications, venous thromboembolism, cerebrovascular and cardiovascular events and endometrial cancer. PCOS is a diagnosis of exclusion, based primarily on the presence of hyperandrogenism, ovulatory dysfunction and PCOM. Treatment should be tailored to the complaints and needs of the patient and involves targeting metabolic abnormalities through lifestyle changes, medication and potentially surgery for the prevention and management of excess weight, androgen suppression and/or blockade, endometrial protection, reproductive therapy and the detection and treatment of psychological features. This Primer summarizes the current state of knowledge regarding the epidemiology, mechanisms and pathophysiology, diagnosis, screening and prevention, management and future investigational directions of the disorder.
Fertility and Sterility | 2012
Bart C.J.M. Fauser; Basil C. Tarlatzis; Robert W. Rebar; Richard S. Legro; Adam Balen; R.A. Lobo; Enrico Carmina; Jeffrey P. Chang; Bulent O. Yildiz; Joop S.E. Laven; Jacky Boivin; Felice Petraglia; C.N. Wijeyeratne; Robert J. Norman; Andrea Dunaif; Stephen Franks; Robert A. Wild; Daniel A. Dumesic; Kurt T. Barnhart
Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in females, with a high prevalence. The etiology of this heterogeneous condition remains obscure, and its phenotype expression varies. Two widely cited previous ESHRE/ASRM sponsored PCOS consensus workshops focused on diagnosis (published in 2004) and infertility management (published in 2008), respectively. The present third PCOS consensus report summarizes current knowledge and identifies knowledge gaps regarding various womens health aspects of PCOS. Relevant topics addressed-all dealt with in a systematic fashion-include adolescence, hirsutism and acne, contraception, menstrual cycle abnormalities, quality of life, ethnicity, pregnancy complications, long-term metabolic and cardiovascular health, and finally cancer risk. Additional, comprehensive background information is provided separately in an extended online publication.
Human Reproduction | 2012
Bulent O. Yildiz; Gurkan Bozdag; Zuhal Yapıcı; Ibrahim Esinler; Hakan Yarali
STUDY QUESTION What is the prevalence, phenotype and metabolic features of polycystic ovary syndrome (PCOS) in the same population according to three different diagnostic criteria? SUMMARY ANSWER The prevalence of PCOS under National Institutes of Health (NIH), Rotterdam and Androgen Excess and PCOS (AE-PCOS) Society criteria was 6.1, 19.9 and 15.3%, respectively. PCOS carried a 2-fold increased risk of metabolic syndrome regardless of the diagnostic criteria used. WHAT IS KNOWN AND WHAT THIS PAPER ADDS The prevalence rates of PCOS differ depending on the diagnostic criteria used to define the syndrome. The current paper gives the prevalence rates of the component and composite phenotypes of PCOS in the same population and reports similar rates of metabolic syndrome in women with PCOS under contrasting diagnostic criteria. DESIGN In this cross-sectional study, 392 women between the ages of 18 and 45 years were analyzed. PARTICIPANTS AND SETTING When the prevalence of PCOS according to NIH was set to 8% with a precision of 2.2% and confidence interval of 95%, the sample size required for a prevalence survey was found to be 400 subjects. The study was carried out in the General Directorate of Mineral Research and Exploration, a government-based institute, in which the largest number of female staff (n = 527) are employed within a single institute in Ankara, Turkey. The study was performed between 7 December 2009 and 30 April 2010. All female subjects between the ages of 18 and 45 years were invited to participate. Women older than 45 or younger than 18 years, post-menopausal women, women with a history of hysterectomy or bilateral oopherectomy and pregnant women were excluded. Totally, 392 of the employees were recruited for the final analyses. MAIN RESULTS AND THE ROLE OF CHANCE The prevalence of PCOS under NIH, Rotterdam and AE-PCOS Society criteria were 6.1, 19.9 and 15.3%, respectively. While the prevalence of metabolic syndrome was 6.1% in the whole study group, within the patients diagnosed as PCOS according to NIH, Rotterdam and AE-PCOS Society criteria, it was 12.5, 10.3 and 10.0%, respectively. BIAS, CONFOUNDING AND OTHER REASONS FOR CAUTION Even though we have included women working at a single institution with a high response rate for the participation, we cannot exclude potential selection bias due to undetermined differences between our sample and background community. We might have underestimated actual prevalence of metabolic syndrome in PCOS due to lack of oral glucose tolerance test 2 h glucose data. GENERALIZABILITY TO OTHER POPULATIONS Current results can be generalized to Caucasian populations and may present variations in other populations according to race and ethnicity. STUDY FUNDING/COMPETING INTEREST(S) This work was, in part, sponsored by Merck Serono. TRIAL REGISTRATION NUMBER Not applicable.
European Journal of Endocrinology | 2014
Gerard S. Conway; Evanthia Diamanti-Kandarakis; Héctor F. Escobar-Morreale; Stephen Franks; Alessandra Gambineri; Fahrettin Kelestimur; Djuro Macut; Dragan Micic; Renato Pasquali; Marija Pfeifer; Duarte Pignatelli; Michel Pugeat; Bulent O. Yildiz
Polycystic ovary syndrome (PCOS) is the most common ovarian disorder associated with androgen excess in women, which justifies the growing interest of endocrinologists. Great efforts have been made in the last 2 decades to define the syndrome. The presence of three different definitions for the diagnosis of PCOS reflects the phenotypic heterogeneity of the syndrome. Major criteria are required for the diagnosis, which in turn identifies different phenotypes according to the combination of different criteria. In addition, the relevant impact of metabolic issues, specifically insulin resistance and obesity, on the pathogenesis of PCOS, and the susceptibility to develop earlier than expected glucose intolerance states, including type 2 diabetes, has supported the notion that these aspects should be considered when defining the PCOS phenotype and planning potential therapeutic strategies in an affected subject. This paper offers a critical endocrine and European perspective on the debate on the definition of PCOS and summarises all major aspects related to aetiological factors, including early life events, potentially involved in the development of the disorder. Diagnostic tools of PCOS are also discussed, with emphasis on the laboratory evaluation of androgens and other potential biomarkers of ovarian and metabolic dysfunctions. We have also paid specific attention to the role of obesity, sleep disorders and neuropsychological aspects of PCOS and on the relevant pathogenetic aspects of cardiovascular risk factors. In addition, we have discussed how to target treatment choices based according to the phenotype and individual patients needs. Finally, we have suggested potential areas of translational and clinical research for the future with specific emphasis on hormonal and metabolic aspects of PCOS.
Human Reproduction | 2012
Bart C.J.M. Fauser; Basil C. Tarlatzis; Robert W. Rebar; Richard S. Legro; Adam Balen; R.A. Lobo; H. Carmina; R.J. Chang; Bulent O. Yildiz; Joop S.E. Laven; Jacky Boivin; Felice Petraglia; C.N. Wijeyeratne; Robert J. Norman; Andrea Dunaif; Stephen Franks; Robert A. Wild; Daniel A. Dumesic; Kurt T. Barnhart
Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in females with a high prevalence. The etiology of this heterogeneous condition remains obscure and its phenotype expression varies. Two, widely cited, previous ESHRE/ASRM-sponsored PCOS consensus workshops focused on diagnosis (published in 2004) and infertility management (published in 2008). The present third PCOS consensus paper summarizes current knowledge and identifies knowledge gaps regarding various womens health aspects of PCOS. Relevant topics addressed-all dealt with in a systematic fashion-include adolescence, hirsutism and acne, contraception, menstrual cycle abnormalities, quality of life, ethnicity, pregnancy complications, long-term metabolic and cardiovascular health and finally cancer risk. Additional, comprehensive background information is provided separately in an extended online publication.
Human Reproduction Update | 2010
Bulent O. Yildiz; Sheila Bolour; Keslie S. Woods; April Moore; Ricardo Azziz
BACKGROUND Hirsutism is the presence of excess body or facial terminal (coarse) hair growth in females in a male-like pattern, affects 5-15% of women, and is an important sign of underlying androgen excess. Different methods are available for the assessment of hair growth in women. METHODS We conducted a literature search and analyzed the published studies that reported methods for the assessment of hair growth. We review the basic physiology of hair growth, the development of methods for visually quantifying hair growth, the comparison of these methods with objective measurements of hair growth, how hirsutism may be defined using a visual scoring method, the influence of race and ethnicity on hirsutism, and the impact of hirsutism in diagnosing androgen excess and polycystic ovary syndrome. RESULTS Objective methods for the assessment of hair growth including photographic evaluations and microscopic measurements are available but these techniques have limitations for clinical use, including a significant degree of complexity and a high cost. Alternatively, methods for visually scoring or quantifying the amount of terminal body and facial hair growth have been in use since the early 1920s; these methods are semi-quantitative at best and subject to significant inter-observer variability. The most common visual method of scoring the extent of body and facial terminal hair growth in use today is based on a modification of the method originally described by Ferriman and Gallwey in 1961 (i.e. the mFG method). CONCLUSION Overall, the mFG scoring method is a useful visual instrument for assessing excess terminal hair growth, and the presence of hirsutism, in women.
Clinical Endocrinology | 2011
Renato Pasquali; Elisabet Stener-Victorin; Bulent O. Yildiz; Antoni J. Duleba; Kathleen M. Hoeger; Helen D. Mason; Roy Homburg; Theresa E. Hickey; S. Franks; Juha S. Tapanainen; Adam Balen; David H. Abbott; Evanthia Diamanti-Kandarakis; Richard S. Legro
Objective To summarize promising areas of investigation into polycystic ovary syndrome (PCOS) and to stimulate further research in this area.
The Journal of Clinical Endocrinology and Metabolism | 2013
U. Ezeh; Bulent O. Yildiz; Ricardo Azziz
BACKGROUND The described phenotype of the polycystic ovary syndrome (PCOS) has been primarily based on findings in a referred (self or otherwise) population. It is possible that the phenotype of PCOS would be different if the disorder were to be detected and studied in its natural (unbiased) state. OBJECTIVE Our objective was to compare the phenotype of PCOS detected in an unselected population with that identified in a referral population. PARTICIPANTS Participants included 292 PCOS patients identified at a tertiary care outpatient facility (referral PCOS) and 64 PCOS women (unselected PCOS) identified through the screening of a population of 668 seeking a pre-employment physical. Among the women undergoing a pre-employment physical, 563 did not demonstrate features of the disorder (unselected controls). All PCOS subjects met the National Institutes of Health 1990 criteria for the disorder. MAIN OUTCOME MEASURES We estimated prevalence of obesity and severity of disease burden. RESULTS Referral PCOS subjects had greater mean body mass index and hirsutism score and higher degrees of hyperandrogenemia, were more likely to be non-Hispanic White (83.90%), and demonstrated a more severe PCOS subphenotype than unselected PCOS or unselected controls. The prevalence of obesity and severe obesity in referral PCOS was 2.3 and 2.5 times greater than estimates of the same in unselected PCOS and 2.2 and 3.8 times greater than estimates in unselected controls, respectively. Alternatively, unselected PCOS subjects had a prevalence of obesity and severe obesity and a mean body mass index similar to those of the general population from which they were derived. CONCLUSION The phenotype of PCOS, including the racial/ethnic mix, severity of presentation, and rate of obesity, is affected significantly by whether the PCOS subject arises from a referral population or through unselected screening, likely reflecting the degree of patient concern and awareness and access to healthcare.
Reviews in Endocrine & Metabolic Disorders | 2007
Bulent O. Yildiz; Ricardo Azziz
Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders characterized by androgen excess, oligo-ovulation and polycystic ovaries. Although ovaries are the main source of increased androgens in the syndrome, between 20 and 30% of patients with PCOS have adrenal androgen (AA) excess, detectable primarily by elevated dehydroepiandrosterone sulfate (DHEAS) levels. Patients with PCOS demonstrate a generalized hypersecretion of adrenocortical products, basally and in response to ACTH stimulation. The mechanisms of these abnormalities are unclear although AA excess in PCOS is likely a complex trait, modulated by both intrinsic and acquired factors. To date, no specific genetic defects have been identified. The production of AAs in response to ACTH appears to be closely related to altered factors regulating glucose-mediated glucose disposal, increased peripheral metabolism of cortisol, and to a less extent to the effects of extra-adrenal androgens, insulin resistance, hyperinsulinemia or obesity. Finally, DHEAS levels and the response of AAs to ACTH are relatively constant over time and are closely correlated between PCOS patients and their siblings suggesting that this abnormality is an inherited trait in PCOS.
Human Reproduction | 2011
Nese Cinar; Muhammed Cemal Kizilarslanoglu; Ayla Harmanci; Duygu Yazgan Aksoy; Gurkan Bozdag; Basaran Demir; Bulent O. Yildiz
BACKGROUND Polycystic ovary syndrome (PCOS) is associated with psychological and metabolic disturbances. The aim of this study was to determine whether depression, anxiety and reduced health-related quality of life (HRQOL) are more common in women with PCOS and associated with metabolic risk. METHODS The study included 226 PCOS patients and 85 BMI-matched healthy control women. All participants completed standardized questionnaires assessing depression (Beck Depression Inventory), anxiety (State-Trait Anxiety Inventory) and both depression and anxiety (Hospital Anxiety and Depression Scale and General Health Questionnaire). Patients also completed a PCOS HRQOL questionnaire. Hirsutism scores, serum androgens and lipids were obtained. All subjects underwent a standard oral glucose tolerance test. RESULTS 28.6% of PCOS women versus 4.7% of control women had clinical depression scores indicating an 8.1-fold increased risk of depression in PCOS (P < 0.001). Depression and anxiety scores were higher in PCOS women than controls (P < 0.01 for all subscales). Obese PCOS subjects had higher depression scores and rates than non-obese PCOS women (P < 0.05). Depression scores were significantly correlated with insulin resistance and lipid parameters and with the number of components comprising the metabolic syndrome. Menstrual and hirsutism problems were the most serious concerns followed by emotional problems on the HRQOL. CONCLUSIONS Depression and anxiety are more common in patients with PCOS compared with healthy women. Depression in PCOS might be associated with obesity and metabolic abnormalities including insulin resistance and dyslipidemia.