The antiandrogenic effect of flutamide improves uterine perfusion in women with polycystic ovary syndrome

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1 FERTILITY AND STERILITY VOL. 77, NO. 6, JUNE 2002 Copyright 2002 American Society for Reproductive Medicine Published by Elsevier Science Inc. Printed on acid-free paper in U.S.A. The antiandrogenic effect of flutamide improves uterine perfusion in women with polycystic ovary syndrome Silvia Ajossa, M.D., Stefano Guerriero, M.D., Anna Maria Paoletti, M.D., Marisa Orrù, Ph.D., and Gian Benedetto Melis, M.D. Department of Obstetrics and Gynecology of the University of Cagliari, Cagliari, Italy Objective: To evaluate whether, by blocking androgen action, flutamide can decrease and normalize vascular resistance in the uterine artery in patients with polycystic ovary syndrome (PCOS). Design: Prospective and controlled study. Setting: Endocrinological Centre of the Department of Obstetrics and Gynecology of the University of Cagliari, Italy. Patient(s): Twenty-two patients with PCOS were enrolled in the study and randomly assigned to one of the following two treatments for 3 months: oral administration of flutamide (250 mg twice daily) or placebo. Intervention(s): Doppler flow measurement of the uterine artery and serum hormone concentration determination during the early follicular phase of the menstrual cycle before treatment and during the third month of treatment. Main Outcome Measure(s): Pulsatility index (PI) of the uterine artery before and during treatment. Result(s): The PI of the uterine artery decreased significantly during treatment. No difference was found in patients treated with placebo. Correlation was found only between the PI values of the uterine artery and DHEAS. Conclusion(s): The low uterine perfusion that characterizes patients with PCOS can be improved by the antiandrogenic effect of flutamide. (Fertil Steril 2002;77: by American Society for Reproductive Medicine.) Key Words: Androgens, DHEAS, flutamide, PCOS, uterine perfusion Received March 7, 2001; revised and accepted November 28, Reprint requests: Silvia Ajossa, M.D., Department of Obstetrics and Gynecology of the University of Cagliari, Ospedale San Giovanni di Dio, Via Ospedale 46, 09124, Cagliari, Italy (FAX: ; gineca.sajossa@tiscal.it) /02/$22.00 PII S (02) Polycystic ovary syndrome (PCOS) is a metabolic disorder that affects several body systems and requires comprehensive, longterm evaluation and management. The introduction of high-resolution pelvic ultrasound scanning has revolutionized research and revealed a wide range of PCOS presentations. It is important, therefore, to exactly define the criteria that may be used to precisely describe this syndrome. These should include oligomenorrhea, hirsutism, endocrinological patterns, and the characteristic ultrasound aspect of ovaries, that is, a large number of small subcapsular follicles, augmented ovarian volume, and increasingly echogenic ovarian stroma (1, 2). The recent application of color Doppler ultrasound technology has enabled investigators to gain new insight into PCOS. In fact, most investigators have observed an increased vascular resistance to uterine perfusion in patients with PCOS (2 6), which leads to reduced uterine perfusion, which is in turn associated with a lower reproductive probability in patients affected by PCOS (7). Many studies have been performed to investigate the causes of the high pulsatility index (PI) values of the uterine artery (2 6, 8), and high androgen levels seem to be the most important factor (2 6). Flutamide is a pure nonsteroidal antiandrogen with no glucocorticoid, progestational, androgenic, estrogenic, or antigonadotropic activity that has been shown to be effective in the treatment of hirsutism. Flutamide blocks the androgen receptors in the central nervous system as well as in the peripheral target organs without interfering with circulating levels of hormonal parameters (9 11). The aim of this study was to evaluate 1136

2 whether, by blocking androgen action, flutamide can decrease and normalize vascular resistance in the uterine artery of patients with PCOS. MATERIALS AND METHODS Study Design A total of 22 women from our Endocrinological Centre took part in the study, which was approved by the local ethics committee and by our institutional review board. All the women were volunteers and gave their informed consent to participate in the study. To avoid interference of the endocrine features of adolescence, only subjects over 20 years of age were enrolled (12), and to avoid interference with weight, only subjects with a normal body mass index were included (13). All the patients were affected by PCOS, which was diagnosed when three or more of the following features were present: oligoamenorrhea, LH:FSH ratio 2.5, high levels of total T, free T, or androstenedione (A), hirsutism score 10, and the typical ultrasound aspect of the PCOS ovaries ( 10 cysts 2 8 mm in diameter arranged around an echogenic stroma). Hirsutism was assessed using Ferriman and Gallwey s global system (14), in which a single observer (S.G.) rated hair growth in 11 body areas on a scale of 0 to 4. A score 10 was established as the threshold for hirsutism in our population (15, 16). All patients underwent transvaginal ultrasound associated with Doppler flow measurement of the uterine artery and serum hormone concentration determination during the early follicular phase (days 2 6 of the menstrual cycle). In patients with amenorrhea (n 5), vaginal bleeding was induced by oral administration of 5 mg of medroxyprogesterone acetate per day for 5 days. The last tablet was taken at least 6 7 days before the examination. All patients with PCOS were randomly assigned to one of the two following treatments: [1] oral administration of flutamide (250 mg twice daily) for 3 months; [2] oral administration of placebo (2 tablets of an inert compound, visually indistinguishable from tablets of the active compound) for 3 months. To study the effect of flutamide as a single agent, no oral contraceptives or any other additional treatment was given. Because of the teratogenic properties of flutamide, it was recommended that all sexually active women use a condom during intercourse. During the third month of treatment, the Doppler flow measurement and the hormonal assessment were repeated in the early follicular phase. Assessment of the Uterine Blood Flow The uterine vessels were visualized by color Doppler, and the ascending branch was identified lateral to the cervix at the level of the internal os. Then blood velocity waveforms were obtained by placing the Doppler gate on the target vessels, ensuring that the angle between the Doppler beam and the vessels was as close to 0 as possible. All ultrasound scans were performed using an Acuson XP/10 OB scanner (Acuson Inc., Mountain View, CA) with a 5-MHz endovaginal probe. Doppler ultrasound, both in color and spectral mode, had a frequency of 5 MHz. A high-pass filter of 125 Hz was used. The spatial peak temporal average intensity of ultrasound for B mode and Doppler examinations was 50 mw/cm 2, which is well within the safety limits recommended by the Bioeffects Committee of the American Institute of Ultrasound in Medicine. All blood flow evaluations were performed at the same time (between 8:00 and 10:00 A.M.) to avoid fluctuations due to the circadian rhythm of the uterine artery blood flow (17). The PI was electronically calculated according to the formula (peak systolic velocities peak diastolic velocities)/mean velocities. The use of a measure of pulsatility flow independent of the incident angle was chosen because it accurately reflects the blood flow impedance and can be used when the end diastolic frequency shift is absent (18). All Doppler measurements were performed by the same operator (S.A.), who did not know to which group the subject belonged, and each measurement was repeated at least three times and then averaged. These mean PI values were used for statistical analysis. A recording was considered satisfactory for measurement when there were at least five equally intense waveforms in a row. The reproducibility of Doppler measurements was tested in 10 patients, where the PI was measured by the same operator three times at 10-minute intervals and studied by analysis of variance. The coefficient of variation was 5.6%. We performed each evaluation only in the right portion of the uterus since some previous studies showed no difference between the right and the left uterine artery in spontaneous cycles (2, 17, 19 21). Hormonal Analysis Blood samples were collected from each patient on the same day as the Doppler flow analysis, and the sera obtained after refrigerated centrifugation were stored at 20 C until the following hormones were assayed: LH, FSH, prolactin (PRL), estradiol (E 2 ), total T, tree T, A, 17-alpha-hydroxyprogesterone (17-OHP), DHEAS, and sex-hormone binding globulin (SHBG). The LH and FSH assays were performed by IRMA (Radim, Pomezia, Rome, Italy), the total T and DHEAS assays by RIA (Radim), the E 2 and A assays by RIA (Biochem, Bologna, Italy), the PRL assay by IRMA (Biochem), the 17-OHP and free T assay by RIA (Medical System, Genoa, Italy), and the SHBG assay by IRMA (Medical System). Each subject also underwent a glucose and a c-peptide assay on the same day. For the 3 days preceding the test, the patients received a diet containing 250 g of glucose per day. Each blood sample was collected in two tubes: 3 ml FERTILITY & STERILITY 1137

3 TABLE 1 Demographic data of the two groups of patients with PCOS. Flutamide group (n 11) were collected in a tube containing lithium heparin (60 IU) and lithium iodoacetate, and 7 ml were collected in a tube containing gel and a clot activator. The samples in the tubes without heparin were immediately centrifuged in a refrigerated centrifuge, and the obtained sera were stored at 20 C. The insulin and c-peptide assay were performed by RIA (Biochem). To avoid interassay interference, blood samples were analyzed in the same assay by the same operator (M.O.). Statistical Analysis Student s t-test for unpaired data (when the same parameters of different groups of patients were analyzed) or paired data (when the same parameters of the same groups of patients were analyzed before and during treatment) were performed whenever appropriate. P.05 was considered statistically significant. The correlation between PI values and all hormonal parameters was evaluated by regression analysis. RESULTS Placebo group (n 11) Age, years Body mass index (hg/m 2 ) Fertility status Nulliparous (%) 10 (90.9) 11 (100) One child (%) 1 (9.1) 0 More than one child 0 0 Ovulatory status Amenorrhea (%) 3 (27.3) 2 (18.2) Oligomenorrhea (%) 8 (72.7) 9 (81.8) Normal cycle 0 0 Hirsutism score PCOS was confirmed in all included patients, and at the baseline there were no differences in the demographic and hormonal data between the two groups of patients (Table 1). In patients with PCOS treated with flutamide, a significant increase in uterine perfusion (P.05) was observed during treatment (Fig. 1), while no difference was found in patients with PCOS treated with placebo (Fig. 1). During treatment with flutamide, no significant changes in hormone assessment were observed even when DHEAS showed a nonsignificant decrease (Table 2). A correlation was found only between PI values of the uterine artery and DHEAS (r.68, P.03). FIGURE 1 Values (mean SD) of PI of uterine artery in patients affected by PCOS before (open bars) and during (solid bars) treatment (*P.05). Side effects did not occur in any of the patients, the treatment did not affect the menstrual cycle, and no changes in P levels were observed before or during treatment. DISCUSSION This study is the first to show that by blocking androgen action at the receptors, flutamide induces an increase in uterine perfusion in patients affected by PCOS. In the past, many investigators have attempted to define the factors that affect uterine perfusion. E 2 definitely plays an important role in moderating uterine vascularization (22, 23). Nevertheless, other factors may be involved in patients with PCOS. Androgens have been shown to exert a direct vasoconstrictive effect on vascular tissues by acting on specific receptors in the artery wall, and a fibrotic process partly mediated by androgen-dependent collagen and elastin deposition on smooth muscle cells has been described (24, 25). Moreover, chronic administration of the dopaminergic compound, cabergoline, induced normalization of the abnormally high adrenal and ovarian androgenin in women with PCOS. This is associated with an increase in uterine perfusion (3). Furthermore, a positive correlation has been found between the PI of the uterine artery and A, T, 17-OHP, and DHEAS (2 5). Insulin too has been hypothesized to interfere with vascular activity. In vitro insulin promotes the accumulation of lipids in the arteries and stimulates smooth muscle cell proliferation in rats. Moreover, it is known that there is a positive correlation between insulin and blood pressure (26 28). In spite of the fundamental role of hyperinsulinemia in inducing disorders of the ovarian function in women affected by PCOS, recent data (5) seem to disagree that it plays a key role in reducing uterine perfusion in these patients Ajossa et al. Flutamide and uterine perfusion in PCOS Vol. 77, No. 6, June 2002

4 TABLE 2 Hormonal parameters before and during treatment in patients with PCOS. Flutamide group Placebo group Hormone Before therapy During therapy Before therapy During therapy LH (IU/L) FSH (IU/L) LH:FSH E 2 I (pg/ml) P (ng/ml) PRL (ng/ml) Total T (ng/ml) Free T (pg/ml) DHEAS ( g/ml) OHP (ng/ml) A (ng/ml) Insulin (pmol/l) The present study seems to confirm this datum, as no correlation was found between insulin levels and PI. Moreover, administration of cabergoline, which is capable of reducing androgen levels and improving uterine perfusion in women with PCOS (3), does not seem to interfere significantly with hyperinsulinemia in women with PCOS (unpublished data). Like cabergoline, flutamide does not significantly interfere with hyperinsulinemia in women with PCOS (11) and can improve their uterine perfusion. Unlike cabergoline, flutamide does not change androgen secretion. However, it is known to have a specific antiandrogenic action, as it also reduces the hirsutism score (11). In fact, flutamide is a specific nonsteroidal antiandrogen compound with no intrinsic hormonal or antihormonal activity other than its ability to block androgen action at the receptor. This study therefore suggests that androgens are the most important factor in determining the resistance of the uterine artery in patients affected by PCOS. Analogously, DHEAS could also be directly or indirectly involved in the resistance of the uterine artery in patients affected by PCOS. In this study, the circulating levels of DHEAS decreased during flutamide treatment and their values were significantly and linearly correlated with the PI values of the uterine artery. Although further studies are needed to clarify the relationship between DHEAS and uterine perfusion, the results of this study suggest that in patients with PCOS normalization of androgen levels could be very important in restoring reproductive performance, since it not only improves menstrual cyclicity but also uterine perfusion (3). However, flutamide treatment is not advisable in patients with PCOS with infertility problems, as it is associated with the risk of feminization of the potential male fetus (9). Therefore, only the use of safer antiandrogenic drugs can be recommended in patients with PCOS seeking pregnancy. Acknowledgments: The authors thank Marina Mannias, M.D., and Stefano Floris, M.D., from the Department of Obstetrics and Gynecology of the University of Cagliari, Cagliari, Italy, for their help in the data collection. The authors are grateful to Mr. Anton Gerada, B.A., M.I.T.I., A.I.I.C., for the language revision of the English manuscript. References 1. Franks S. Polycystic ovary syndrome: a changing perspective. Clin Endocrinol 1989;31: Battaglia C, Artini PG, D Ambrogio G, Genazzani AD, Genazzani AR. The role of color Doppler imaging in the diagnosis of polycystic ovary syndrome. Am J Obstet Gynecol 1995;172: Ajossa S, Paoletti AM, Guerriero S, Floris S, Mannias M, Melis GB. Effect of chronic administration of cabergoline on uterine perfusion in women with polycystic ovary syndrome. Fertil Steril 1999;71: Battaglia C, Artini PG, Genazzani AD, Gremigni R, Salvatori M, Sgherzi MR, et al. Color Doppler analysis in oligo and amenorrheic women with polycystic ovary syndrome. Gynecol Endocrinol 1997;11: Battaglia C, Artini PG, Genazzani AD, Scherzi MR, Salvatori M, Guilini S, et al. Color Doppler analysis in lean and obese women with polycystic ovary syndrome. Ultrasound Obstet Gynecol 1996;7: Aalem F, Predanic M. Transvaginal color Doppler determination of the ovarian and uterine blood flow characteristics in polycystic ovary disease. Fertil Steril 1996;65: Chappel SC, Howles C. Reevaluation of the role of luteinizing hormone and follicle-stimulating hormone in the ovulatory process. Hum Reprod 1991;6: Vrtacnik-Bokal E, Meden-Vrtovec H. Utero-ovarian blood flow and hormonal profile in patients with polycystic ovary syndrome. Hum Reprod 1998;13: Couzinet B, Pholsena M, Young J, Schaison G. The impact of a pure anti-androgen (flutamide) on LH, FSH androgens and clinical status in idiopathic hirsutism. Clin Endocrinol 1993;39: Erenus M, Gurbuz O, Durmusoglu F, Demircay Z, Pekin S. Comparison of the efficacy of spironolactone versus flutamide in the treatment of hirsutism. Fertil Steril 1994;61: Paoletti AM, Cagnacci A, Orrù M, Ajossa S, Guerriero S, Melis GB. FERTILITY & STERILITY 1139

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