http://informahealthcare.com/gye ISSN: 0951-3590 (print), 1473-0766 (electronic) Gynecol Endocrinol, 2014; 30(10): 697–700 ! 2014 Informa UK Ltd. DOI: 10.3109/09513590.2014.922948
OVARIAN RESERVE AND CARDIOVASCULAR RISK
Is there any relationship between cardiovascular risk markers and young women with diminished ovarian reserve? Fatma Ferda Verit1, Seda Keskin1, Beyhan Omer2, Sener Yalcinkaya1, and Nafi Sakar1 1
Gynecol Endocrinol Downloaded from informahealthcare.com by Michigan University on 02/13/15 For personal use only.
Department of Obstetrics & Gynecology, Infertility Research & Treatment Center, Suleymaniye Maternity, Research & Training Hospital, Istanbul, Turkey and 2Department of Biochemistry, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
Abstract
Keywords
Objective: It has been widely known that cardiovascular disease (CVD) risk is increased in menopause. The aim of the study was to evaluate whether this risk was elevated in young women with diminished ovarian reserve (DOR). Methods: A hundred women with DOR and 100 women with normal ovarian reserve (NOR) attending the infertility unit at Suleymaniye Maternity, Research &Training Hospital, were enrolled in the study. CVD risk markers such as insulin resistance (defined by the homeostasis model assessment ratio [HOMA-IR]), C-reactive protein (CRP), low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (TC), and triglyceride (TG) were assessed. Results: HOMA-IR, CRP, TG, LDL levels were higher and HDL was lower among patients with DOR compared to the controls (p50.05 for all). There were positive associations between DOR and HOMA-IR, CRP, TG, LDL levels and a negative correlation with HDL (p50.05 for all). However, multivariate logistic regression analysis showed that HOMA-IR, CRP, TG, and HDL were independent variables that were associated with DOR. Conclusions: CVD risk markers were increased in women with DOR. Further studies with larger groups are needed to investigate the nature of the link in these patients.
Cardiovascular risk, C-reactive protein, diminished ovarian reserve, dyslipidemia, insulin resistance
Introduction Diminished ovarian reserve (DOR) is an ovarian dysfunction that is characterized by decreased oocyte quality and quantity [1]. The prevalence of DOR was reported to be 10% in young women [2]. The normal physiological aging shifts toward younger age as declining ovarian reserve markers in these patients and premature ovarian aging is observed. Cardiovascular disease (CVD) is the one of the leading cause of morbidity and mortality in the world and atherosclerosis is known to be the main reason for the increased cardiovascular risk. It has been reported that inflammation plays an important role in atherosclerosis [3]. Inflammatory factors such as monocyte/ macrophage colony stimulating factor, transforming growth factor-b1, interleukin-6 and C-reactive protein (CRP) are shown to be related with atherogenesis [4]. CRP was found to be strongly associated with coronary artery disease and ischemic stroke in a meta-analysis [5]. Furthermore, CRP was found to be correlated with fatal and non-fatal CVD in another study [6]. Insulin resistance is an important co-factor in the pathophysiology of CVD [7]. It is related with obesity, dyslipidemia and it is known to be one of the components of the metabolic syndrome [8]. It is also associated with low-grade chronic inflammation [9]. Cardiovascular insulin resistance leads to endothelial dysfunction,
Address for correspondence: Fatma Ferda Verit, Department of Obstetrics and Gynecology, Suleymaniye Maternity, Research &Training Hospital, Istanbul, Turkey. Tel: +90 212 6645355. Fax: +90 212 4169814. E-mail: [email protected]
History Received 29 January 2014 Revised 10 April 2014 Accepted 7 May 2014 Published online 10 June 2014
impaired cardiac diastolic, and vascular relaxation, decreased coronary blood flow and increased susceptibility to ischemia [10]. It has been reported that CVD is increased with ‘ovarian aging or accelerated follicular loss’ such as primary ovarian insufficiency and menopause [11]. Estrogen has been suggested to offer some cardiovascular protective effect in premenopausal women [12]. Reduced estrogen production from ovaries may contribute to dyslipidemia, adverse effects in glucose and insulin metabolism, body fat distribution, coagulation and fibrinolysis and dysfunction in vascular endothelium [13]. However, the risk of CVD in young women with DOR has not been studied in detail. The aim of the study was to investigate whether there was any relationship between young women with DOR and CVD with cardiovascular risk markers such as insulin resistance, CRP and dyslipidemia.
Materials and methods This prospective study was performed in the infertility unit at Suleymaniye Maternity, Research & Training Hospital with a total of 200 infertile patients who met our eligibility criteria and gave informed consent at the initiation of the study between August 2012 and April 2013. Of these, a hundred were women with DOR and 100 of them were women with Normal Ovarian Reserve (NOR). NOR group consisted of infertile patients such as unexplained infertility, tubal or male factor. All the infertile patients had undergone IVF treatment. The study was approved by Institutional Review Board. Patients were considered to have DOR if they have antral follicle count (AFC) 5 combined with serum FSH levels 8 IU/L and/or E2480 pg/mL on day 3 of a spontaneous cycle.
Gynecol Endocrinol Downloaded from informahealthcare.com by Michigan University on 02/13/15 For personal use only.
698
F. F. Verit et al.
NOR group had AFC6 and serum Day3 FSH levels58 IU/L and/or E2580 pg/mL. While on day 3 FSH levels 10 U/L had been used in the definition of DOR, we used cut-off FSH 8 IU/L specific to our study population of women 35 years [14]. The primary exclusion criteria were hypothalamic amenorrhea, premature ovarian failure, congenital adrenal hyperplasia, androgen-secreting tumors or ovarian tumor, Cushing syndrome, CVD, diabetes mellitus, insulin resistance, metabolic syndrome, hypertension, obesity (body mass index [BMI] greater than or equal to 30 kg/m2), hyperlipidemia, history of major depression, using any psychoactive medications, cocaine or opiates, age above 35 years, the presence of neoplastic disease, infectious diseases, autoimmune diseases, liver or kidney disease, smoking and alcohol consumption. CVD was defined according to 2013 American College of Cardiology/American Heart Association Guidelines [15]. Hypertension was defined as a systolic blood pressure (SBP) of 140 mm Hg or a diastolic blood pressure (DBP) of 90 mm Hg or those who were receiving antihypertensive therapy at the time of the examination. Insulin resistance was estimated by the homeostasis model assessment of insulin resistance (HOMA-IR) using the following formula: fasting blood sugar (mg/dL) fasting insulin (mIU/mL)/ 405 [16]. The patients were classified as insulin resistant if HOMA-IR44 [16]. Metabolic syndrome was defined (based on the guidelines from the 2005 National Cholesterol Education program (NCEP) [Adult Treatment Panel (ATP III)] as the presence of at least three of the following criteria: – Abdominal obesity (WC greater than 88 cm in women). – Serum triglyceride (TG) 150 mg/dl or taking any medication for hypertriglyceridemia – Serum high-density lipoprotein (HDL) 550 mg/dl or taking any medication for reduced HDL level – Blood pressure (BP) 130/85 mmHg or taking any medication for hypertension – Fasting blood glucose 100 mg/dl or taking any medication for hyperglycemia [17]. All the participants underwent standardized initial clinical, sonographic and endocrine screening. Clinical screening included age, cycle history, BMI, waist to hip ratio (WHR), duration of infertility, and previous medication, and/or surgery. Endocrine screening included serum assays for glucose, insulin, prolactin, FSH, LH, TSH, estradiol, progesterone and total testosterone (T). Studies were performed between the menstrual cycle day 3 and 5. Fasting venous blood samples were taken between 08.00–10.00 h after a 12 h overnight fast. Then the blood samples were centrifuged within 2 h after withdrawal and assessed on the same day.
Gynecol Endocrinol, 2014; 30(10): 697–700
transformed for all analyses. A power analysis was calculated for each cardiovascular risk markers that were assessed in this study. The projected sample-size changed from 18 to 78 (a level ¼ 0.05) with a power of 80% in each group. Laboratory and anthropometric parameters of patients were compared by Student’s-t test for continuous variables and 2 test for categorical variables. Correlations between DOR and fasting glucose, fasting insulin, HOMA-IR, CRP, TG, LDL and HDL were assessed by Spearman’s rank test. In addition, multivariate logistic regression analysis was applied to analyze the association between cardiovascular risk markers and DOR. Data were considered significant at p50.05.
Results Baseline characteristics of the study and control groups were demonstrated in Table 1. There were no differences in terms of age, BMI, WHR, duration of infertility, previous pregnancies and duration of treatment (p40.05) (Table 1). Women with DOR had significantly higher levels of day 3 FSH, day 3 E2, total dose of FSH used, however, antral follicle count and number of oocytes retrieved were significantly lower in that group (p50.05, for all; Table 1). Biochemical parameters of the groups were summarized in Table 2. Fasting glucose, insulin, HOMA-IR, CRP, TG and LDL levels were significantly elevated in women with DOR (p50.05, for all; Table 2). There was no difference in TC levels in both
Table 1. Baseline characteristics of the groups.
Variables Age (years) BMI (kg/m2) WHR Duration of infertility (years) Previous pregnancies Day 3 FSH (mIU/mL) Day 3 E2 (pg/mL) Antral follicle count Total dose of FSH used (IU) Duration of treatment (days) Number of oocytes retrieved
Women with DOR (n ¼ 100) (mean ± SD)
Women with NOR (n ¼ 100) (mean ± SD)
p
30.5 ± 3.1 24.9 ± 2.7 0.7 ± 0.0 6.0 ± 1.9
30.0 ± 3.3 24.5 ± 2.4 0.7 ± 0.0 5.7 ± 1.7
0.24 0.31 0.30 0.32
9 (9.0%) 10.1 ± 3.8 90.3 ± 18.4 3.9 ± 1.0 4080.4 ± 916.3
10 (10.0%) 5.7 ± 1.4 48.6 ± 14.3 13.0 ± 4.5 2850.5 ± 717.7
0.80 50.0001 50.0001 50.0001 50.0001
9.7 ± 1.6
9.3 ± 1.5
0.13
2.0 ± 1.4
11.0 ± 3.0
50.0001
BMI:bodymassindex, WHR: waist to hip ratio.
Blood sample collection Blood samples were collected at 9:00 and 11:00 a.m. after an overnight fast. Then the blood samples were centrifuged within 2 h after withdrawal and assessed on the same day. CRP levels were determined by nephelometric assay (Siemens BN-Prospec Nephelometer; Siemens, Munich, Germany). Insulin was determined by electrochemiluminescent immunoassay (Cobas e411, Roche Diagnostics, Indianopolis, IN).The levels of triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL) and low density lipoprotein (LDL) were determined by using commercially available assay kits (Abbott) with an autoanalyzer (Aeroset, Abbott).
Table 2. Biochemical parameters of study and control groups.
Variables Fasting glucose (mg/dL) Fasting insulin (mg/dL) HOMA-IR CRP (mg/L) TG (mg/dL) HDL (mg/dL) LDL (mg/dL) TC (mg/dL)
Women with DOR (n ¼ 100) (mean ± SD)
Women with NOR (n ¼ 100) (mean ± SD)
p
99.8 ± 10.3 10.3 ± 4.0 2.5 ± 1.0 4.9 ± 1.7 134.1 ± 31.5 61.9 ± 10.6 100.9 ± 23.5 179.1 ± 32.7
95.4 ± 9.9 8.6 ± 3.1 2.0 ± 0.8 4.4 ± 1.4 121.6 ± 31.2 67.1 ± 10.6 92.9 ± 21.6 175.9 ± 31.4
0.003 0.001 50.0001 0.032 0.005 0.001 0.014 0.47
Statistical analysis Baseline characteristics of the groups were shown as the mean ± SD. Variables with a skewed distribution were log
HOMA-IR:homeostasis model assessment ratio LDL:lowdensitylipoprotein TC:total cholesterol, CRP:C- reactive protein, TG:triglyceride, HDL:highdensitylipoprotein.
Cardiovascular risk in diminished ovarian reserve
DOI: 10.3109/09513590.2014.922948
Table 3. Regression analysis of the variables that influenced DOR in the study. Variables
b
S.E
Wald
p
HOMA-IR CRP TG HDL LDL
0.7 0.2 0.0 0.0 0.0
0.1 0.1 0.0 0.0 0.0
14.4 3.9 8.4 5.5 1.9
50.0001 0.048 0.004 0.019 0.16
Gynecol Endocrinol Downloaded from informahealthcare.com by Michigan University on 02/13/15 For personal use only.
HOMA-IR:homeostasis model assessment ratio, CRP:C- reactive protein, TG:triglyceride, HDL:highdensitylipoprotein, LDL: lowdensitylipoprotein.
groups, but HDL levels were decreased in DOR group (p50.05; Table 2). There were positive associations between women with DOR and fasting glucose (r ¼ 0.22, p ¼ 0.001), insulin (r ¼ 0.21, p ¼ 0.003), HOMA-IR (r ¼ 0.25, p50.0001), CRP (r ¼ 0.16, p ¼ 0.020), LDL (r ¼ 0.17, p ¼ 0.022) and TG (r ¼ 0.18, p ¼ 0.011). HDL was negatively correlated with DOR (r ¼ 0.23, p ¼ 0.001) in the study. Multivariate logistic regression analysis was used to study the relationship between DOR and HOMA-IR, CRP, and dyslipidemia. HOMA-IR, CRP, TG, and HDL were the independent predictors that were associated with DOR (p50.005, for all). The test statistic for Hosmer-Lemeshow goodness-of-fit test had a value of 3.9 for with 8 degrees for freedom and a p value of 0.86 indicating that the model provided a good fit to the data.
Discussion In this study, we demonstrated that cardiovascular risk markers such as HOMA-IR, CRP and dyslipidemia were increased in young women with DOR. There were also positive associations between DOR and HOMA-IR, CRP, TG, LDL and a negative relationship with HDL. Of these markers, HOMA-IR, CRP, TG and HDL were independent variables that were associated with DOR. Oocyte pool is established at birth and declines with somatic and ovarian aging. A faster rate of ovarian aging is demonstrated after the follicle number drops to 1000 that were accepted as menopausal threshold. It has been known widely that the morbidity and mortality rate is increased with post-menopausal women. An inverse relationship was shown between the age at menopause and all-cause mortality rate [18]. CVD is one of the most common diseases that are increased with menopausal transition, since it has been widely known that women have the same risk of developing CVD with male counterparts after menopause. It has been reported that women with primary ovarian insufficiency were more prone to CVD, thus abnormal glucose metabolism and dyslipidemia were highly prevalent in these patients [11]. It has been suggested that reproductive aging may be accelerated in women with DOR and it may be linked with early menopause [19]. de Boer et al. reported that women who had low number of oocyte retrieval at first IVF treatment reach the natural menopause earlier [19]. The menopause age of the women with DOR was 6–7 years earlier compared with those with NOR [19]. It has been thought that ovarian aging first begins with subfertility, then infertility, increasing abortion rates, chromosomal aberrations, irregular menstrual cycles and finally menopause [20]. It is clear that the timing of these events is associated with decreasing quantity and quality of resting follicle pool that is also known as DOR. It has been demonstrated that women with DOR have higher urinary FSH levels in their early follicular phase and impaired
699
luteal phase urinary excretions of estradiol and progesterone metabolites are similar compared with women in menopausal transition [21]. Granulosa cell dysfunction is also seen in women with DOR [22]. Decreases in estrogen production and hypoestrogenism may underlie health morbidities such as proatherogenic profile, CVD and osteoporosis as it was seen in early menopause [23]. It has been shown that peri-menopausal women with DOR those have elevated FSH levels have dyslipidemia [24]. The association between AMH, ovarian reserve marker, and cardiometabolic risk factors such as HOMA-IR, TG, HDL, WHR and the hypertensive status in pre-menopausal women were evaluated in another study [25]. The study showed that lowand mid-levels of AMH were associated with a 52.1% and 46.0% increase in cardiometabolic risk factors respectively [25]. It has been concluded that women with high AMH and good ovarian reserve had healthier cardiometabolic risk-factor profile [25]. However, the relationship between cardiovascular risk markers and DOR in young infertile group without carrying any cardiovascular risk factors has not been studied before. In this study, we demonstrated that cardiovascular risk markers such as HOMA-IR, CRP and dyslipidemia were increased in young women with DOR. There were also positive associations between DOR and HOMA-IR, CRP, TG, LDL and a negative relationship with HDL. In this study, women with DOR were infertile patients that also have high-levels of psychologic stress such as depression and anxiety. This chronic stress has been known to affect pregnancy and live birth rates adversely [26]. Depression and anxiety may also alter immunomodulation and lead to vascular dysfunction that all contribute to CVD [27]. Insulin resistance and chronic inflammation are associated with cardiovascular risk and these could be used as CVD markers that were shown by many studies [6,7,9]. Both of those markers induce many changes in blood lipid levels leading to proatherogenic lipid profile [28,29]. Insulin resistance is also linked with hypertension, hypercoagulability, endothelial dysfunction and atherosclerosis [30]. CRP is reported to be an independent risk factor for myocardial infarction, stroke and peripheral vascular disease [31]. CRP was the strongest predictor of the CVD among 12 baseline measures, including lipids and homocysteine [32]. HOMA-IR, CRP, TG, LDL and HDL had close relationship with DOR in the study. Of these markers, HOMA-IR, CRP, TG and HDL were independent variables that were associated with DOR. These markers are components of metabolic syndrome and they are remarkable markers in detecting CVD. The strength of the study was that we studied with an nonobese young group without carrying any cardiovascular risk, to eliminate these factors on CVD markers. There were close relationship between DOR and cardiovascular risk-factors and most of them were independently associated with DOR. Moreover, the study showed that Hosmer-Lemeshow test provided a good fit to the data. One of the limitations of the study was that the study population was small and further studies with larger groups are warranted. Other weakness of the study was the absence of definite markers of atherosclerosis such as endothelial dysfunction and carotid intima thickness. In conclusion, we found that CVD risk may be increased in women with DOR. Cardiovascular consultation and lifestyle changes may be warranted in these patients. Further studies with larger groups are needed to investigate the nature of this link in young women with DOR.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
700
F. F. Verit et al.
Gynecol Endocrinol, 2014; 30(10): 697–700
Gynecol Endocrinol Downloaded from informahealthcare.com by Michigan University on 02/13/15 For personal use only.
References 1. Wang TT, Ke ZH, Song Y, Chen LT, et al. Identification of a mutation in GDF9 as a novel cause of diminished ovarian reserve in young women. Hum Reprod 2013;28:2473–81. 2. Nikolaou D, Templeton A. Early ovarian ageing: a hypothesis. Detection and clinical relevance. Hum Reprod 2003; 18:1137–9. 3. Bevc S, Sabic S, Hojs R. Atherosclerosis in hemodialysis patients – the role of microinflammation. Ren Fail 2008;30:1012–16. 4. Ikonomidis I, Stamatelopoulos K, Lekakis J, et al. Inflammatory and non-invasive vascular markers: the multimarker approach for risk stratification in coronary artery disease. Atherosclerosis 2008;199: 3–11. 5. Kaptoge S, Di Angelantonio E, Lowe G, et al. Emerging risk factors collaboration. C-reactive protein concentration and risk of coronary heart disease, stroke, and mortality: an individual participant metaanalysis. Lancet 2010;375:132–40. 6. van Wijk DF, Boekholdt SM, Wareham NJ, et al. C-reactive protein, fatal and nonfatal coronary artery disease, stroke, and peripheral artery disease in the prospective EPIC-Norfolk cohort study. Arterioscler Thromb Vasc Biol 2013;33:2888–94. 7. Despre´s JP, Lamarche B, Maurie`ge P, et al. Hyperinsulinemia as an independent risk factor for ischemic heart disease. N Engl J Med 1996;334:952–7. 8. Farin HM, Abbasi F, Kim SH, et al. The relationship between insulin resistance and dyslipidaemia in cigarette smokers. Diabetes Obes Metab 2007;9:65–9. 9. Kemp DM. Does chronic low-grade endotoxemia define susceptibility of obese humans to insulin resistance via dietary effects on gut microbiota? Adipocyte 2013;2:188–90. 10. Aroor A, McKarns S, Nistala R, et al. DPP-4 Inhibitors as therapeutic modulators of immune cell function and associated cardiovascular and renal insulin resistance in obesity and diabetes. Cardiorenal Med 2013;3:48–56. 11. Wellons M. Cardiovascular disease and primary ovarian insufficiency. Semin Reprod Med 2011;29:328–41. 12. Torng PL, Su TC, Sung FC, et al. Effects of menopause on intraindividual changes in serum lipids, blood pressure, and body weight – the Chin-Shan Community Cardiovascular Cohort study. Atherosclerosis 2002;161:409–15. 13. Spencer CP, Godsland H, Stevenson JC. Is there a menopausal metabolic syndrome? Gynecol Endocrinol 1977;11:341–55. 14. Kahapola Arachchige KM, Wardrop R, et al. Waiting for an elevated FSH – too late a marker of reduced ovarian reserve? Aust N Z J Obstet Gynaecol 2012;52:460–4. 15. Goff DC Jr, Lloyd-Jones DM, Bennett G, et al. 2013 ACC/AHA Guideline on the assessment of cardiovascular risk: a report of the American College of Cardiology/American Heart association task force on practice guidelines. Circulation 2013. [Epub ahead of print]. 16. Matthews DR, Hosker JP, Rudenski AS, et al. Homeostasis model assessment: insulin resistance and beta-cell function from fasting
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30. 31. 32.
plasma glucose and insulin concentrations in man. Diabetologia 1985;28:412–19. Grundy SM, Cleeman JI, Daniels SR, et al.; American Heart Association; National Heart, Lung, and Blood Institute. Diagnosis and management of the metabolic syndrome: an American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement. Circulation 2005;112:2735–52. Jacobsen BK, Heuch I, Kva˚le G. Age at natural menopause and allcause mortality: a 37-year follow-up of 19,731 Norwegian women. Am J Epidemiol 2003;157:923–9. de Boer EJ, den Tonkelaar I, te Velde ER, et al. OMEGA-project group. Increased risk of early menopausal transition and natural menopause after poor response at first IVF treatment. Hum Reprod 2003;18:1544–52. de Boer EJ, den Tonkelaar I, te Velde ER, et al.; OMEGA-project group. A low number of retrieved oocytes at in vitro fertilization treatment is predictive of early menopause. Fertil Steril 2002;77: 978–85. Pal L, Zhang K, Zeitlian G, Santoro N. Characterizing the reproductive hormone milieu in infertile women with diminished ovarian reserve. Fertil Steril 2010;93:1074–9. Greenseid K, Jindal S, Zapantis A, et al. Declining ovarian reserve adversely influences granulosa cell viability. Fertil Steril 2009;91: 2611–15. Matthews KA, Wing RR, Kuller LH, et al. Influence of the perimenopause on cardiovascular risk factors and symptoms of middle-aged healthy women. Arch Intern Med 1994;154:2349–55. Chu MC, Rath KM, Huie J, Taylor HS. Elevated basal FSH in normal cycling women is associated with unfavourable lipid levels and increased cardiovascular risk. Hum Reprod 2003;18:1570–3. Bleil ME, Gregorich SE, McConnell D, et al. Does accelerated reproductive aging underlie premenopausal risk for cardiovascular disease? Menopause 2013;20:1139–46. Gaikwad S, Garrido N, Cobo A, et al. Bed rest after embryo transfer negatively affects in vitro fertilization: a randomized controlled clinical trial. Fertil Steril 2013;100:729–35. Loftis JM, Huckans M, Morasco BJ. Neuroimmune mechanisms of cytokine-induced depression: current theories and novel treatment strategies. Neurobiol Dis 2010;37:519–33. Khovidhunkit W, Kim M, Memon R, et al. Effects of infection and inflammation on lipid and lipoprotein metabolism: mechanisms and consequences to the host. J Lipid Res 2004;45:1169–96. Rizzo M, Rizvi AA, Rini GB, Berneis K. The therapeutic modulation of atherogenic dyslipidemia and inflammatory markers in the metabolic syndrome: what is the clinical relevance? Acta Diabetol 2009;46:1–11. Ginsberg HN. Insulin resistance and cardiovascular disease. J Clin Invest 2000;106:453–8. Hansson GK. Atherosclerosis – an immune disease: the Anitschkov Lecture 2007. Atherosclerosis 2009;202:2–10. Kelly CC, Lyall H, Petrie JR, et al. Low grade chronic inflammation in women with polycystic ovarian syndrome. J Clin Endocrinol Metab 2001;86:2453–5.
OVARIAN RESERVE AND CARDIOVASCULAR RISK
Is there any relationship between cardiovascular risk markers and young women with diminished ovarian reserve? Fatma Ferda Verit1, Seda Keskin1, Beyhan Omer2, Sener Yalcinkaya1, and Nafi Sakar1 1
Gynecol Endocrinol Downloaded from informahealthcare.com by Michigan University on 02/13/15 For personal use only.
Department of Obstetrics & Gynecology, Infertility Research & Treatment Center, Suleymaniye Maternity, Research & Training Hospital, Istanbul, Turkey and 2Department of Biochemistry, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
Abstract
Keywords
Objective: It has been widely known that cardiovascular disease (CVD) risk is increased in menopause. The aim of the study was to evaluate whether this risk was elevated in young women with diminished ovarian reserve (DOR). Methods: A hundred women with DOR and 100 women with normal ovarian reserve (NOR) attending the infertility unit at Suleymaniye Maternity, Research &Training Hospital, were enrolled in the study. CVD risk markers such as insulin resistance (defined by the homeostasis model assessment ratio [HOMA-IR]), C-reactive protein (CRP), low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (TC), and triglyceride (TG) were assessed. Results: HOMA-IR, CRP, TG, LDL levels were higher and HDL was lower among patients with DOR compared to the controls (p50.05 for all). There were positive associations between DOR and HOMA-IR, CRP, TG, LDL levels and a negative correlation with HDL (p50.05 for all). However, multivariate logistic regression analysis showed that HOMA-IR, CRP, TG, and HDL were independent variables that were associated with DOR. Conclusions: CVD risk markers were increased in women with DOR. Further studies with larger groups are needed to investigate the nature of the link in these patients.
Cardiovascular risk, C-reactive protein, diminished ovarian reserve, dyslipidemia, insulin resistance
Introduction Diminished ovarian reserve (DOR) is an ovarian dysfunction that is characterized by decreased oocyte quality and quantity [1]. The prevalence of DOR was reported to be 10% in young women [2]. The normal physiological aging shifts toward younger age as declining ovarian reserve markers in these patients and premature ovarian aging is observed. Cardiovascular disease (CVD) is the one of the leading cause of morbidity and mortality in the world and atherosclerosis is known to be the main reason for the increased cardiovascular risk. It has been reported that inflammation plays an important role in atherosclerosis [3]. Inflammatory factors such as monocyte/ macrophage colony stimulating factor, transforming growth factor-b1, interleukin-6 and C-reactive protein (CRP) are shown to be related with atherogenesis [4]. CRP was found to be strongly associated with coronary artery disease and ischemic stroke in a meta-analysis [5]. Furthermore, CRP was found to be correlated with fatal and non-fatal CVD in another study [6]. Insulin resistance is an important co-factor in the pathophysiology of CVD [7]. It is related with obesity, dyslipidemia and it is known to be one of the components of the metabolic syndrome [8]. It is also associated with low-grade chronic inflammation [9]. Cardiovascular insulin resistance leads to endothelial dysfunction,
Address for correspondence: Fatma Ferda Verit, Department of Obstetrics and Gynecology, Suleymaniye Maternity, Research &Training Hospital, Istanbul, Turkey. Tel: +90 212 6645355. Fax: +90 212 4169814. E-mail: [email protected]
History Received 29 January 2014 Revised 10 April 2014 Accepted 7 May 2014 Published online 10 June 2014
impaired cardiac diastolic, and vascular relaxation, decreased coronary blood flow and increased susceptibility to ischemia [10]. It has been reported that CVD is increased with ‘ovarian aging or accelerated follicular loss’ such as primary ovarian insufficiency and menopause [11]. Estrogen has been suggested to offer some cardiovascular protective effect in premenopausal women [12]. Reduced estrogen production from ovaries may contribute to dyslipidemia, adverse effects in glucose and insulin metabolism, body fat distribution, coagulation and fibrinolysis and dysfunction in vascular endothelium [13]. However, the risk of CVD in young women with DOR has not been studied in detail. The aim of the study was to investigate whether there was any relationship between young women with DOR and CVD with cardiovascular risk markers such as insulin resistance, CRP and dyslipidemia.
Materials and methods This prospective study was performed in the infertility unit at Suleymaniye Maternity, Research & Training Hospital with a total of 200 infertile patients who met our eligibility criteria and gave informed consent at the initiation of the study between August 2012 and April 2013. Of these, a hundred were women with DOR and 100 of them were women with Normal Ovarian Reserve (NOR). NOR group consisted of infertile patients such as unexplained infertility, tubal or male factor. All the infertile patients had undergone IVF treatment. The study was approved by Institutional Review Board. Patients were considered to have DOR if they have antral follicle count (AFC) 5 combined with serum FSH levels 8 IU/L and/or E2480 pg/mL on day 3 of a spontaneous cycle.
Gynecol Endocrinol Downloaded from informahealthcare.com by Michigan University on 02/13/15 For personal use only.
698
F. F. Verit et al.
NOR group had AFC6 and serum Day3 FSH levels58 IU/L and/or E2580 pg/mL. While on day 3 FSH levels 10 U/L had been used in the definition of DOR, we used cut-off FSH 8 IU/L specific to our study population of women 35 years [14]. The primary exclusion criteria were hypothalamic amenorrhea, premature ovarian failure, congenital adrenal hyperplasia, androgen-secreting tumors or ovarian tumor, Cushing syndrome, CVD, diabetes mellitus, insulin resistance, metabolic syndrome, hypertension, obesity (body mass index [BMI] greater than or equal to 30 kg/m2), hyperlipidemia, history of major depression, using any psychoactive medications, cocaine or opiates, age above 35 years, the presence of neoplastic disease, infectious diseases, autoimmune diseases, liver or kidney disease, smoking and alcohol consumption. CVD was defined according to 2013 American College of Cardiology/American Heart Association Guidelines [15]. Hypertension was defined as a systolic blood pressure (SBP) of 140 mm Hg or a diastolic blood pressure (DBP) of 90 mm Hg or those who were receiving antihypertensive therapy at the time of the examination. Insulin resistance was estimated by the homeostasis model assessment of insulin resistance (HOMA-IR) using the following formula: fasting blood sugar (mg/dL) fasting insulin (mIU/mL)/ 405 [16]. The patients were classified as insulin resistant if HOMA-IR44 [16]. Metabolic syndrome was defined (based on the guidelines from the 2005 National Cholesterol Education program (NCEP) [Adult Treatment Panel (ATP III)] as the presence of at least three of the following criteria: – Abdominal obesity (WC greater than 88 cm in women). – Serum triglyceride (TG) 150 mg/dl or taking any medication for hypertriglyceridemia – Serum high-density lipoprotein (HDL) 550 mg/dl or taking any medication for reduced HDL level – Blood pressure (BP) 130/85 mmHg or taking any medication for hypertension – Fasting blood glucose 100 mg/dl or taking any medication for hyperglycemia [17]. All the participants underwent standardized initial clinical, sonographic and endocrine screening. Clinical screening included age, cycle history, BMI, waist to hip ratio (WHR), duration of infertility, and previous medication, and/or surgery. Endocrine screening included serum assays for glucose, insulin, prolactin, FSH, LH, TSH, estradiol, progesterone and total testosterone (T). Studies were performed between the menstrual cycle day 3 and 5. Fasting venous blood samples were taken between 08.00–10.00 h after a 12 h overnight fast. Then the blood samples were centrifuged within 2 h after withdrawal and assessed on the same day.
Gynecol Endocrinol, 2014; 30(10): 697–700
transformed for all analyses. A power analysis was calculated for each cardiovascular risk markers that were assessed in this study. The projected sample-size changed from 18 to 78 (a level ¼ 0.05) with a power of 80% in each group. Laboratory and anthropometric parameters of patients were compared by Student’s-t test for continuous variables and 2 test for categorical variables. Correlations between DOR and fasting glucose, fasting insulin, HOMA-IR, CRP, TG, LDL and HDL were assessed by Spearman’s rank test. In addition, multivariate logistic regression analysis was applied to analyze the association between cardiovascular risk markers and DOR. Data were considered significant at p50.05.
Results Baseline characteristics of the study and control groups were demonstrated in Table 1. There were no differences in terms of age, BMI, WHR, duration of infertility, previous pregnancies and duration of treatment (p40.05) (Table 1). Women with DOR had significantly higher levels of day 3 FSH, day 3 E2, total dose of FSH used, however, antral follicle count and number of oocytes retrieved were significantly lower in that group (p50.05, for all; Table 1). Biochemical parameters of the groups were summarized in Table 2. Fasting glucose, insulin, HOMA-IR, CRP, TG and LDL levels were significantly elevated in women with DOR (p50.05, for all; Table 2). There was no difference in TC levels in both
Table 1. Baseline characteristics of the groups.
Variables Age (years) BMI (kg/m2) WHR Duration of infertility (years) Previous pregnancies Day 3 FSH (mIU/mL) Day 3 E2 (pg/mL) Antral follicle count Total dose of FSH used (IU) Duration of treatment (days) Number of oocytes retrieved
Women with DOR (n ¼ 100) (mean ± SD)
Women with NOR (n ¼ 100) (mean ± SD)
p
30.5 ± 3.1 24.9 ± 2.7 0.7 ± 0.0 6.0 ± 1.9
30.0 ± 3.3 24.5 ± 2.4 0.7 ± 0.0 5.7 ± 1.7
0.24 0.31 0.30 0.32
9 (9.0%) 10.1 ± 3.8 90.3 ± 18.4 3.9 ± 1.0 4080.4 ± 916.3
10 (10.0%) 5.7 ± 1.4 48.6 ± 14.3 13.0 ± 4.5 2850.5 ± 717.7
0.80 50.0001 50.0001 50.0001 50.0001
9.7 ± 1.6
9.3 ± 1.5
0.13
2.0 ± 1.4
11.0 ± 3.0
50.0001
BMI:bodymassindex, WHR: waist to hip ratio.
Blood sample collection Blood samples were collected at 9:00 and 11:00 a.m. after an overnight fast. Then the blood samples were centrifuged within 2 h after withdrawal and assessed on the same day. CRP levels were determined by nephelometric assay (Siemens BN-Prospec Nephelometer; Siemens, Munich, Germany). Insulin was determined by electrochemiluminescent immunoassay (Cobas e411, Roche Diagnostics, Indianopolis, IN).The levels of triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL) and low density lipoprotein (LDL) were determined by using commercially available assay kits (Abbott) with an autoanalyzer (Aeroset, Abbott).
Table 2. Biochemical parameters of study and control groups.
Variables Fasting glucose (mg/dL) Fasting insulin (mg/dL) HOMA-IR CRP (mg/L) TG (mg/dL) HDL (mg/dL) LDL (mg/dL) TC (mg/dL)
Women with DOR (n ¼ 100) (mean ± SD)
Women with NOR (n ¼ 100) (mean ± SD)
p
99.8 ± 10.3 10.3 ± 4.0 2.5 ± 1.0 4.9 ± 1.7 134.1 ± 31.5 61.9 ± 10.6 100.9 ± 23.5 179.1 ± 32.7
95.4 ± 9.9 8.6 ± 3.1 2.0 ± 0.8 4.4 ± 1.4 121.6 ± 31.2 67.1 ± 10.6 92.9 ± 21.6 175.9 ± 31.4
0.003 0.001 50.0001 0.032 0.005 0.001 0.014 0.47
Statistical analysis Baseline characteristics of the groups were shown as the mean ± SD. Variables with a skewed distribution were log
HOMA-IR:homeostasis model assessment ratio LDL:lowdensitylipoprotein TC:total cholesterol, CRP:C- reactive protein, TG:triglyceride, HDL:highdensitylipoprotein.
Cardiovascular risk in diminished ovarian reserve
DOI: 10.3109/09513590.2014.922948
Table 3. Regression analysis of the variables that influenced DOR in the study. Variables
b
S.E
Wald
p
HOMA-IR CRP TG HDL LDL
0.7 0.2 0.0 0.0 0.0
0.1 0.1 0.0 0.0 0.0
14.4 3.9 8.4 5.5 1.9
50.0001 0.048 0.004 0.019 0.16
Gynecol Endocrinol Downloaded from informahealthcare.com by Michigan University on 02/13/15 For personal use only.
HOMA-IR:homeostasis model assessment ratio, CRP:C- reactive protein, TG:triglyceride, HDL:highdensitylipoprotein, LDL: lowdensitylipoprotein.
groups, but HDL levels were decreased in DOR group (p50.05; Table 2). There were positive associations between women with DOR and fasting glucose (r ¼ 0.22, p ¼ 0.001), insulin (r ¼ 0.21, p ¼ 0.003), HOMA-IR (r ¼ 0.25, p50.0001), CRP (r ¼ 0.16, p ¼ 0.020), LDL (r ¼ 0.17, p ¼ 0.022) and TG (r ¼ 0.18, p ¼ 0.011). HDL was negatively correlated with DOR (r ¼ 0.23, p ¼ 0.001) in the study. Multivariate logistic regression analysis was used to study the relationship between DOR and HOMA-IR, CRP, and dyslipidemia. HOMA-IR, CRP, TG, and HDL were the independent predictors that were associated with DOR (p50.005, for all). The test statistic for Hosmer-Lemeshow goodness-of-fit test had a value of 3.9 for with 8 degrees for freedom and a p value of 0.86 indicating that the model provided a good fit to the data.
Discussion In this study, we demonstrated that cardiovascular risk markers such as HOMA-IR, CRP and dyslipidemia were increased in young women with DOR. There were also positive associations between DOR and HOMA-IR, CRP, TG, LDL and a negative relationship with HDL. Of these markers, HOMA-IR, CRP, TG and HDL were independent variables that were associated with DOR. Oocyte pool is established at birth and declines with somatic and ovarian aging. A faster rate of ovarian aging is demonstrated after the follicle number drops to 1000 that were accepted as menopausal threshold. It has been known widely that the morbidity and mortality rate is increased with post-menopausal women. An inverse relationship was shown between the age at menopause and all-cause mortality rate [18]. CVD is one of the most common diseases that are increased with menopausal transition, since it has been widely known that women have the same risk of developing CVD with male counterparts after menopause. It has been reported that women with primary ovarian insufficiency were more prone to CVD, thus abnormal glucose metabolism and dyslipidemia were highly prevalent in these patients [11]. It has been suggested that reproductive aging may be accelerated in women with DOR and it may be linked with early menopause [19]. de Boer et al. reported that women who had low number of oocyte retrieval at first IVF treatment reach the natural menopause earlier [19]. The menopause age of the women with DOR was 6–7 years earlier compared with those with NOR [19]. It has been thought that ovarian aging first begins with subfertility, then infertility, increasing abortion rates, chromosomal aberrations, irregular menstrual cycles and finally menopause [20]. It is clear that the timing of these events is associated with decreasing quantity and quality of resting follicle pool that is also known as DOR. It has been demonstrated that women with DOR have higher urinary FSH levels in their early follicular phase and impaired
699
luteal phase urinary excretions of estradiol and progesterone metabolites are similar compared with women in menopausal transition [21]. Granulosa cell dysfunction is also seen in women with DOR [22]. Decreases in estrogen production and hypoestrogenism may underlie health morbidities such as proatherogenic profile, CVD and osteoporosis as it was seen in early menopause [23]. It has been shown that peri-menopausal women with DOR those have elevated FSH levels have dyslipidemia [24]. The association between AMH, ovarian reserve marker, and cardiometabolic risk factors such as HOMA-IR, TG, HDL, WHR and the hypertensive status in pre-menopausal women were evaluated in another study [25]. The study showed that lowand mid-levels of AMH were associated with a 52.1% and 46.0% increase in cardiometabolic risk factors respectively [25]. It has been concluded that women with high AMH and good ovarian reserve had healthier cardiometabolic risk-factor profile [25]. However, the relationship between cardiovascular risk markers and DOR in young infertile group without carrying any cardiovascular risk factors has not been studied before. In this study, we demonstrated that cardiovascular risk markers such as HOMA-IR, CRP and dyslipidemia were increased in young women with DOR. There were also positive associations between DOR and HOMA-IR, CRP, TG, LDL and a negative relationship with HDL. In this study, women with DOR were infertile patients that also have high-levels of psychologic stress such as depression and anxiety. This chronic stress has been known to affect pregnancy and live birth rates adversely [26]. Depression and anxiety may also alter immunomodulation and lead to vascular dysfunction that all contribute to CVD [27]. Insulin resistance and chronic inflammation are associated with cardiovascular risk and these could be used as CVD markers that were shown by many studies [6,7,9]. Both of those markers induce many changes in blood lipid levels leading to proatherogenic lipid profile [28,29]. Insulin resistance is also linked with hypertension, hypercoagulability, endothelial dysfunction and atherosclerosis [30]. CRP is reported to be an independent risk factor for myocardial infarction, stroke and peripheral vascular disease [31]. CRP was the strongest predictor of the CVD among 12 baseline measures, including lipids and homocysteine [32]. HOMA-IR, CRP, TG, LDL and HDL had close relationship with DOR in the study. Of these markers, HOMA-IR, CRP, TG and HDL were independent variables that were associated with DOR. These markers are components of metabolic syndrome and they are remarkable markers in detecting CVD. The strength of the study was that we studied with an nonobese young group without carrying any cardiovascular risk, to eliminate these factors on CVD markers. There were close relationship between DOR and cardiovascular risk-factors and most of them were independently associated with DOR. Moreover, the study showed that Hosmer-Lemeshow test provided a good fit to the data. One of the limitations of the study was that the study population was small and further studies with larger groups are warranted. Other weakness of the study was the absence of definite markers of atherosclerosis such as endothelial dysfunction and carotid intima thickness. In conclusion, we found that CVD risk may be increased in women with DOR. Cardiovascular consultation and lifestyle changes may be warranted in these patients. Further studies with larger groups are needed to investigate the nature of this link in young women with DOR.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
700
F. F. Verit et al.
Gynecol Endocrinol, 2014; 30(10): 697–700
Gynecol Endocrinol Downloaded from informahealthcare.com by Michigan University on 02/13/15 For personal use only.
References 1. Wang TT, Ke ZH, Song Y, Chen LT, et al. Identification of a mutation in GDF9 as a novel cause of diminished ovarian reserve in young women. Hum Reprod 2013;28:2473–81. 2. Nikolaou D, Templeton A. Early ovarian ageing: a hypothesis. Detection and clinical relevance. Hum Reprod 2003; 18:1137–9. 3. Bevc S, Sabic S, Hojs R. Atherosclerosis in hemodialysis patients – the role of microinflammation. Ren Fail 2008;30:1012–16. 4. Ikonomidis I, Stamatelopoulos K, Lekakis J, et al. Inflammatory and non-invasive vascular markers: the multimarker approach for risk stratification in coronary artery disease. Atherosclerosis 2008;199: 3–11. 5. Kaptoge S, Di Angelantonio E, Lowe G, et al. Emerging risk factors collaboration. C-reactive protein concentration and risk of coronary heart disease, stroke, and mortality: an individual participant metaanalysis. Lancet 2010;375:132–40. 6. van Wijk DF, Boekholdt SM, Wareham NJ, et al. C-reactive protein, fatal and nonfatal coronary artery disease, stroke, and peripheral artery disease in the prospective EPIC-Norfolk cohort study. Arterioscler Thromb Vasc Biol 2013;33:2888–94. 7. Despre´s JP, Lamarche B, Maurie`ge P, et al. Hyperinsulinemia as an independent risk factor for ischemic heart disease. N Engl J Med 1996;334:952–7. 8. Farin HM, Abbasi F, Kim SH, et al. The relationship between insulin resistance and dyslipidaemia in cigarette smokers. Diabetes Obes Metab 2007;9:65–9. 9. Kemp DM. Does chronic low-grade endotoxemia define susceptibility of obese humans to insulin resistance via dietary effects on gut microbiota? Adipocyte 2013;2:188–90. 10. Aroor A, McKarns S, Nistala R, et al. DPP-4 Inhibitors as therapeutic modulators of immune cell function and associated cardiovascular and renal insulin resistance in obesity and diabetes. Cardiorenal Med 2013;3:48–56. 11. Wellons M. Cardiovascular disease and primary ovarian insufficiency. Semin Reprod Med 2011;29:328–41. 12. Torng PL, Su TC, Sung FC, et al. Effects of menopause on intraindividual changes in serum lipids, blood pressure, and body weight – the Chin-Shan Community Cardiovascular Cohort study. Atherosclerosis 2002;161:409–15. 13. Spencer CP, Godsland H, Stevenson JC. Is there a menopausal metabolic syndrome? Gynecol Endocrinol 1977;11:341–55. 14. Kahapola Arachchige KM, Wardrop R, et al. Waiting for an elevated FSH – too late a marker of reduced ovarian reserve? Aust N Z J Obstet Gynaecol 2012;52:460–4. 15. Goff DC Jr, Lloyd-Jones DM, Bennett G, et al. 2013 ACC/AHA Guideline on the assessment of cardiovascular risk: a report of the American College of Cardiology/American Heart association task force on practice guidelines. Circulation 2013. [Epub ahead of print]. 16. Matthews DR, Hosker JP, Rudenski AS, et al. Homeostasis model assessment: insulin resistance and beta-cell function from fasting
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30. 31. 32.
plasma glucose and insulin concentrations in man. Diabetologia 1985;28:412–19. Grundy SM, Cleeman JI, Daniels SR, et al.; American Heart Association; National Heart, Lung, and Blood Institute. Diagnosis and management of the metabolic syndrome: an American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement. Circulation 2005;112:2735–52. Jacobsen BK, Heuch I, Kva˚le G. Age at natural menopause and allcause mortality: a 37-year follow-up of 19,731 Norwegian women. Am J Epidemiol 2003;157:923–9. de Boer EJ, den Tonkelaar I, te Velde ER, et al. OMEGA-project group. Increased risk of early menopausal transition and natural menopause after poor response at first IVF treatment. Hum Reprod 2003;18:1544–52. de Boer EJ, den Tonkelaar I, te Velde ER, et al.; OMEGA-project group. A low number of retrieved oocytes at in vitro fertilization treatment is predictive of early menopause. Fertil Steril 2002;77: 978–85. Pal L, Zhang K, Zeitlian G, Santoro N. Characterizing the reproductive hormone milieu in infertile women with diminished ovarian reserve. Fertil Steril 2010;93:1074–9. Greenseid K, Jindal S, Zapantis A, et al. Declining ovarian reserve adversely influences granulosa cell viability. Fertil Steril 2009;91: 2611–15. Matthews KA, Wing RR, Kuller LH, et al. Influence of the perimenopause on cardiovascular risk factors and symptoms of middle-aged healthy women. Arch Intern Med 1994;154:2349–55. Chu MC, Rath KM, Huie J, Taylor HS. Elevated basal FSH in normal cycling women is associated with unfavourable lipid levels and increased cardiovascular risk. Hum Reprod 2003;18:1570–3. Bleil ME, Gregorich SE, McConnell D, et al. Does accelerated reproductive aging underlie premenopausal risk for cardiovascular disease? Menopause 2013;20:1139–46. Gaikwad S, Garrido N, Cobo A, et al. Bed rest after embryo transfer negatively affects in vitro fertilization: a randomized controlled clinical trial. Fertil Steril 2013;100:729–35. Loftis JM, Huckans M, Morasco BJ. Neuroimmune mechanisms of cytokine-induced depression: current theories and novel treatment strategies. Neurobiol Dis 2010;37:519–33. Khovidhunkit W, Kim M, Memon R, et al. Effects of infection and inflammation on lipid and lipoprotein metabolism: mechanisms and consequences to the host. J Lipid Res 2004;45:1169–96. Rizzo M, Rizvi AA, Rini GB, Berneis K. The therapeutic modulation of atherogenic dyslipidemia and inflammatory markers in the metabolic syndrome: what is the clinical relevance? Acta Diabetol 2009;46:1–11. Ginsberg HN. Insulin resistance and cardiovascular disease. J Clin Invest 2000;106:453–8. Hansson GK. Atherosclerosis – an immune disease: the Anitschkov Lecture 2007. Atherosclerosis 2009;202:2–10. Kelly CC, Lyall H, Petrie JR, et al. Low grade chronic inflammation in women with polycystic ovarian syndrome. J Clin Endocrinol Metab 2001;86:2453–5.
