==== Front Ann Saudi MedAnn Saudi MedAnnals of Saudi Medicine0256-49470975-4466King Faisal Specialist Hospital and Research Centre 2406071110.5144/0256-4947.2013.339asm-4-339Original ArticleGender inequality in the clinical outcomes of equally treated acute coronary syndrome patients in Saudi Arabia Hersi Ahmad aAl-Habib Khalid aAl-Faleh Husam bAl-Nemer Khalid cAlSaif Shukri dTaraben Amir eKashour Tarek aAbuosa Ahmed Mohamed fAl-Murayeh Mushabab Ayedh g a Colllege of Medicine, King Saud University, Cardiac Science, King Khalid University Hospital, Riyadh, Saudi Arabia b Cardiology, King Khalid University Hospital, Riaydh, Saudi Arabia c Medicine, Security Forces Hospital, Riyadh, Saudi Arabia d Cardiology, Saud AlBabtain Cardiac Center, Dammam, Saudi Arabia e Medicine, King Faisal Specialist Hospital and Research Center, Jeddah, Saudi Arabia f Medicine, King Khalid National Guard Hospital, Jeddah, Saudi Arabia g Department of Cardiology, Armed Forces Hospital Southern Region, Aseer, Saudi ArabiaCorrespondence: Dr. Ahmad Hersi, Colllege of Medicine, King Saud University, Cardaic Science, King Khalid University Hospital, Riyadh 11472, Saudi Arabia, ahersi@ksu.edu.saJul-Aug 2013 33 4 339 346 Copyright © 2013, Annals of Saudi Medicine2013This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.BACKGROUND AND OBJECTIVES Gender associations with acute coronary syndrome (ACS), remain inconsistent. Gender-specific data in the Saudi Project for Assessment of Coronary Events registry, launched in December 2005 and currently with 17 participating hospitals, were explored. DESIGN AND SETTINGS A prospective multicenter study of patient with ACS in secondary and tertiary care centers in Saudi Arabia were included in this analysis. PATIENTS AND METHODS Patients enrolled from December 2005 until December 2007 included those presented to participating hospitals or transferred from non-registry hospitals. Summarized data were analyzed. RESULTS Of 5061 patients, 1142 (23%) were women. Women were more frequently diagnosed with non ST-segment elevation myocardial infarction (NSTEMI [43%]) than unstable angina (UA [29%]) or ST-segment elevation myocardial infarction (STEMI [29%]). More men had STEMI (42%) than NSTEMI (37%) or UA (22%). Men were younger than women (57 vs 63 years) who had more diabetes, hypertension, and hyperlipidemia. More men had a history of coronary artery disease. More women received angiotensin receptor blockers (ARB) and fewer had percutaneous coronary intervention (PCI). Gender differences in the subset of STEMI patients were similar to those in the entire cohort. However, gender differences in the subset of STEMI showed fewer women given β-blockers, and an insignificant PCI difference between genders. Thrombolysis rates between genders were similar. Overall, in-hospital mortality was significantly worse for women and, by ACS type, was significantly greater in women for STEMI and NSTEMI. However, after age adjustment there was no difference in mortality between men and women in patients with NSTEMI. The multivariate-adjusted (age, risk factors, treatments, door-to-needle time) STEMI gender mortality difference was not significant (OR=2.0, CI: 0.7–5.5; P=.14). CONCLUSION These data are similar to other reported data. However, differences exist, and their explanation should be pursued to provide a valuable insight into understanding ACS and improving its management. ==== Body Coronary artery disease (CAD) is well recognized as a most common cause of death in both women and men in large parts of the industrialized world.1 Over the past decade, the existence of sex/gender differences in terms of presentation of symptoms, validity of diagnostic tests, in-hospital medication, drug side effects, clinical outcomes, complications, and management of acute coronary syndrome (ACS) are frequently reported in the published reports.2–5 The prevalence of ACS diagnosed in emergency departments is lower for women than men,6 with rates dependent on clinical presentation at the time of admission. The percentage of women diagnosed with ACS can range from 33% to 45%.7 Furthermore, a smaller percentage of women than men presented with ST-elevation myocardial infarction (STEMI) (secondary to occlusive thrombus), but more presented with unstable angina (reflecting subtotal occlusion).1,8 Moreover, sex differences in symptoms of ACS exist, which might be explained by differences in anatomic, physiologic, bio logic, and psychologic characteristics among them.3,9 Previous studies demonstrating important differences in the outcomes of men and women with ACS have focused on the management and the performance of revascularization procedures.10–12 A systematic review of the diagnosis and treatment of CAD found significant evidence that women admitted to hospital with ACS are less likely to receive aspirin, β-blockers, or thrombolysis; less likely to undergo exercise stress testing; and also are less likely to undergo angiography or revascularization. 13 Although not all studies have found such gender differences, particularly after adjusting for important confounding factors such as age.14,15 Several studies are available from Western countries on gender disparities in ACS treatment and outcomes; however, no data is available from Saudi Arabia. Accordingly; our objective was to explore whether gender-related differences exist in the treatment and outcomes of patients presenting with ACS in Saudi Arabia. PATIENTS AND METHODS The Saudi Project for Assessment of Coronary Events study is a prospective registry and a quality improvement initiative of all consecutive ACS patients that were admitted to the participating hospitals.16 Ethical approval was obtained in all participating centers. The diagnosis of the different types of ACS was based on the definitions of the Joint Committee of the European Society of Cardiology/American College of Cardiology (ACC).16 Serum cardiac biomarkers used to assist in the diagnosis of myocardial injury were measured locally at each hospital’s laboratory using its own assays and reference ranges. Study design and population ACS patients include those with STEMI, non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina (UA). We report here the results of the 2 phases of the study that lasted from December 2005 until December 2007. There were 13 hospitals in phase-I and 17 in phase-II; one third of the hospitals were nontertiary care hospitals with no cardiac catheterization and/or cardiac surgery facilities. The details of these phases were outlined previously.17 In summary, phase-I extended over a 1-year period and included baseline registry of process of care, outcomes, and health care services. Subsequently, the overall and individual-hospital results were sent to each hospital to improve on the knowledge-care gap and get a comparison with national practices. Phase-II extended for another 1 year and data was collected using the Internet (www.space-ksa.com). Overall and individual-hospital results were also provided “real-time” during this on-line phase to all participating hospitals. Study organization A case report form (CRF) for each patient with suspected ACS was filled out on hospital admission by assigned physicians working in each hospital using standard definitions, and then was completed throughout the hospital stay. All CRFs were verified by a cardiologist and then sent to the principal coordinating center where the forms were further checked for incomplete data and mistakes before submission for final analysis. To avoid double-counting patients, each patient’s national identification number was used. An independent clinical research organization (Dubai Pharmaceutical, Dubai, UAE) was contracted to randomly audit all data collected from 20% of the hospitals in phase-I. Data accuracy was found to be more than 99%. Case report form data variables Data collected included the following variables: patients’ demographics, medical history, provisional diagnosis on admission and final discharge diagnosis, electrocardiographic findings, laboratory investigations, medical therapy, use of cardiac procedures and interventions, inhospital outcomes, and mortality. Statistics Differences in categorical variables between respective comparison groups were analyzed using the chi-square test or Fisher exact test. Continuous variables were analyzed using a t test or Mann-Whitney U test based on the satisfaction of normality assumption. P values were reported as 2-sided test results with a 5% level of significance for each test. Multiple logistic regression analysis was used to identify whether gender was an independent predictor of in-hospital mortality. Variables considered for inclusion were baseline demographic characteristics medical history diabetes mellitus, hypertension, hyperlipidemia, percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG), in-hospital therapies, and door-to-needle-time. All analyses were performed using STATA version 9 (StataCorp LP, United States). RESULTS A total of 5061 patients with the diagnosis of ACS were enrolled from 30 hospitals during the period between December 2005 and December 2007. Table 1 depicts the baseline characteristics of the whole cohort. A total of 77.4% (3919) were men and 22.3% (1142) were women. The mean age of women was 63 years compared with 57 years for men (P<.001) (Table 1). Women had significantly higher baseline risks like diabetes mellitus, hypertension, hyperlipidemia, higher body mass index and tachycardia in men (P<.001 for all comparisons). However, the prevalence of CAD in men was higher than in women (15.2% vs 11.2%; P=.001), but there was no difference in the rate of men and women who underwent PCI and CABG surgery without any disparity. A significant difference in presenting diagnosis based on gender was observed where STEMI was common in male patients (45.2% vs 28.6%, P<.001), whereas the NSTEMI (34.6% vs 42.6%; P<.001) and UA (20.1% vs 28.7%; P<.001) were more common in women patients (Figure 1). There was no significant difference between men and women in terms of symptoms at presentation to hospital (89.3% vs 81.9%; P=.4). Women were more likely than men to have more severe clinical abnormalities (i.e., lower systolic BP and higher pulse rate) but less likely than their male peers to have unusual chest pain. The incidence of cerebrovascular accident/transient ischemic attack and peripheral artery disease was not different between the 2 groups. Moreover, key diagnostic investigations like troponin and coronary angiogram were similar in both the genders. In-hospital medications and clinical outcome comparisons No significant differences were observed in the administration of aspirin, clopidogrel, angiotensin converting enzyme inhibitors/blockers, β-blocker, and lipid-lowering agents between female and male patients in the hospital. PCI was more significantly performed in men than women (36.3% vs 31.6%; P=.001); however, there was no significant difference in the rate of CABG between the 2 groups. The rate of in-hospital death was significantly more in women than men (5.2% vs 2.5%; P=.02), the rate of congestive heart failure (CHF) was significantly more in women than men (16.2% vs 8.6%, P<.001), and the rate of recurrent ischemia was also significantly more in women than men (14.5% vs 12.1%, P=.02). Moreover the rate of cardiogenic shock (5.3% vs 4.1%, P=.07), stroke (1.4% vs 0.8%, P=.07), major bleeding (1.9% vs 1.2%, P=.05), and re-MI (remyocardial infarction) (2.0% vs 1.4%, P=.12) were not significantly different between the 2 groups. Table 2 depicts the demographic, in-hospital treatment, and the outcomes of patients with STEMI. The mean age of women was significantly higher than of men (62.5 vs 56.7, P=.001). There was no difference in the use of evidence-based medication or the rate of thrombolytic and primary PCI between the 2 groups. Women had higher in–hospital mortality rate (11% vs 3.3% P<.001), higher CHF (20.2% vs 9.8%, P<.001), and higher cardiogenic shock rate (11% vs 6.95, P=.01) than men. However; there was no significant difference in the rate of major bleeding, stroke or re-MI between the 2 groups. In-hospital mortality Table 3 depicts the crude and age-adjusted odds ratios (OR) associated with the in-hospital mortality. The crude OR associated with the in-hospital mortality was higher in women 3.5 (95% CI: 2.3–5.5) for SETMI and was 2 (95% CI: 1.2–3.5) for NSTEMI. There was no significant difference in the mortality between the 2 groups in patients with UA. Age-adjusted OR for the in-hospital mortality was higher in women for STEMI 2.5 (95% CI: 1.5–3.8; P<.001) and was not significant for NSTEMI OR 1.5 (95% CI: 0.97–2.9; P=.060). Multiple logistic regression models were developed to adjust for potential confounders that may explain the gender variability in mortality (Table 4). When we adjusted for baseline characteristics or in-hospital treatments, excess mortality in women was significantly higher (adjusted odd ratio [AOR] 2 [95% CI: 1.2–3; P=.003] and AOR 2.5 [95% CI: 1.4–4.2; P=.001], respectively). When we adjusted for treatment and risk factors, excess mortality in women was significantly higher aand AOR was 2 (95% CI: 1.1–3.4; P=.017). Adding DNT time, the AOR was no longer significant, i.e., 2 (95% CI: 0.7–5.5; P=.14). DISCUSSION This study provides information on the demographics, in-hospital treatment, and outcomes of women presenting with ACS compared to men in Saudi Arabia. The main findings of the present study were that the Saudi women developed ACS at higher age, had a higher prevalence of traditional risk factor, equally treated with evidence-based therapies with a significant delay in the administration in these therapies, and had worse inhospital outcomes than men. Previous reports showed that women had their first cardiac event 6 to 10 years later than men and had higher attributable risk factors. 18 Furthermore, typically, more women with ACS present without chest pain or discomfort; however, the difference is not universal and prompted12,19,20 to emphasize that public health symptom messages should not be changed to include lesser chest pain in women. In the present study, neither the lesser frequency of ischemic chest pain nor the slightly greater frequency of atypical chest pain in women compared with men was significant. Saudi women presented more often with UA and NSTEMI, whereas men had more frequently STEMI, which is in accordance with earlier studies such as GUSTO IIb (Global Use of Strategies to Open Occluded Coronary Arteries in Acute Coronary Syndromes), TIMI IIIB (Thrombolysis In Myocardial Infarction), and the Euro Heart Survey.21–23 These gender- related differences may be accounted for the differences in anatomy, pathophysiology of CAD, and clinical characteristics in women versus men.21 Concerning patient management, there is conflicting evidence for a gender-related bias. Several studies documented a clear gender bias in referral to diagnostic procedures and treatment of coronary artery disease.24–26 American College of Cardiology/American Heart Association guidelines for NSTEMI ACS care at hospital discharge include aspirin, clopidogrel, β-blockers, ACE inhibitor, lipid-lowering agent, smoking cessation, dietary modification, counseling, and cardiac rehabilitation. In our study, in-hospital medications irrespective of gender followed the protocol treatment guidelines. However, more female patients were prescribed angiotensin receptor blockers compared to men, possibly for renal protection attributing to higher baseline risk factors such as diabetes.27,28 In addition, no significant differences were noted in the rate of CABG or thrombolytic therapies between the 2 groups; however, the rate of PCI was significantly lower in female patients than male. Like other reports,29 our study showed that CHF and recurrent ischemia were more often reported in the female group, whereas no significant gender difference was found in the occurrence of cardiogenic shock, stroke, major bleeding, and re-MI rate. For example, Maynard et al reported a higher incidence of CHF in women ACS patients during hospitalization,30–32 suggestive of diastolic dysfunction as a large component of the presentation of heart failure in ACS women.22 In one of the studies, a subset of women presented with STEMI showed higher rate of in-hospital mortality than men.7 This difference was attributed to their older age, higher baseline risks, more frequent comorbidities, and less frequent use of revascularization or undertreatment, or restricted to a subgroup of female patients (possibly related to smaller target vessel size, increased vessel tortuosity, and other biological differences). 33–36 Similar to our study several reports from randomized clinical trial (GUSTO, ISIS 3) and lager databases (RESCATE, Washington, NARMI) indicate that women gender is an independent risk factor for CHF, cardiogenic shock and in-hospital mortality after adjusting for age, comorbidities and evidence-based therapies for STEMI. In addition, it is argued that under-referral of women may have been the cause of increased morbidity and mortality in women, particularly associated with PCI procedure.37,38 However, there was no difference in rate of referral for PCI in our STEMI between the groups. Moreover, reports indicate that women with STEMI tend to delay seeking medical attention than men (GUSTO 1), upon arrival to the hospital they typically experience further delay in administration of thrombolytic therapy. Jacson et al reported that women waited a mean of 23 minutes longer before receiving thrombolytic therapy than men (112.2 [84.1] vs 89.6 [68.7]) minutes, P<.1; median 100 and 75 minutes, women and men, respectively. In our study there was a significant delay in administrating thrombolytic therapy to women, which is not explained by differences in symptoms at presentation (median 52 vs 71 minutes, men and women, respectively; P=.035). Adjusting for DTN time did remove the increased in-hospital mortality in women with STEMI. Limitations Our data is based on observational registry. The main limitation of such design is nonrandomized nature and unmeasured cofounders. However, well-designed registry data provide valid results. We did not systematically capture the time of onset of symptoms to hospital presentation, which perhaps confounded the findings of this study. In conclusion, women develop ACS at a higher age in Saudi and have higher attributable baseline risk factors. They predominantly present with NSTEMI and unstable angina. Saudi women with STEMI independently predicted poorer outcomes in terms of CHF, cardiogenic shock, and in-hospital mortality. In our study, this finding is related to delay in the administration of thrombolytic therapy. Hence physicians need to increase the awareness of prompted administration of effective therapy in women with STEMI. Acknowledgments This study was funded by Sanofi Aventis. Figure 1 Distribution of gender according to the ACS type. Table 1 Baseline characteristics of patients with ACS stratified by gender in Saudi Arabia. Variables Overall n=5061 n (%) Male N=3919(77.4) Female N=1142 (22.6) P value Age (mean [SD]) 58.01 (12.9) 56.7 (12.9) 62.5 (11.9) <.001 Key risk factors  Diabetes mellitus 2937 (58.1) 2104 (41.6) 835 (73.2) <.001  Nationality (Saudi) 4167 (82.4) 3104 (61.4) 1063 (93.2) <.001  Hypertension 2785 (55.3) 1936 (49.5) 849 (75.1) <.001  Coronary artery disease 718 (14.2) 592 (15.2) 126 (11.2) .001  PCI 700 (13.8) 543 (13.9) 157 (13.7) .65  CABG 296 (5.8) 232 (5.9) 64 (5.6) .36  Smoker 1636 (32.3) 1591 (40.6) 45 (3.9) <.001  Hyperlipidemia 2086 (45.4) 1526 (39.0) 560 (49.6) <.001  CVA/TIA 309 (6.1) 228 (5.8) 81 (7.1) .24  PAD 203 (10.5) 149 (10) 54 (11.5) .22 Clinical features on presentation  Systolic BP≤90 148 (3.2) 116 (3.3) 32 (3.0) .72  Heart rate≥100 679 (14.9) 468 (13.3) 211 (20.2) <.001  Body mass index 27.6 (6.1) 27.7 (4.3) 29.7 (6.9) <.001  Ischemic chest pain 3057 (87.6) 2419 (89.3) 638 (81.9) .4  Atypical chest pain 115 (3.3) 84 (3.1) 31 (4) .8 Key investigations  Troponin 3152 (62.5) 2453 (62.9) 699 (61.4) .21  Coronary angiogram 3403 (67.2) 2658 (67.8) 745 (65.3) .27 In-hospital treatment  Aspirin 4935 (97.7) 3826 (97.9) 1109 (97.4) .19  Clopidogrel 4231 (83.8) 3273 (83.7) 958 (84.1) .74  β-blocker 4120 (81.6) 3206 (82) 914 (80.2) .18  ACEI 3508 (69.5) 2735 (69.9) 773 (67.9) .17  ARB 297 (5.9) 183 (4.7) 114 (10.0) <.001  Statin 4711 (93.3) 3656 (93.5) 1055 (92.6) .29  PCI 1775 (35.3) 1416 (36.3) 356 (31.6) .001  CABG 425 (8.4) 332 (8.5) 93 (8.1) .52 In-hospital outcomes  Recurrent ischemia 639 (12.6) 473 (12.1) 166 (14.5) .02  Re-MI 77 (1.5) 54 (1.4) 23 (2.0) .12  Death 155 (3.0) 96 (2.5) 59 (5.2) <.001  CHF 520 (10.2) 335 (8.6) 185 (16.2) <.001  Cardiogenic shock 222 (4.4) 161 (4.1) 61 (5.3) .07  Major bleeding 68 (1.3) 46 (1.2) 22 (1.9) .05  Stroke 48 (0.9) 32 (0.8) 16 (1.4) .07 Discharge diagnosis  STEMI 2099 (41.5) 1772 (45.2) 327 (28.6) <.0001  NSTEMI 1844 (36.5) 1357 (34.6) 487 (42.6) <.0001  UA 1118 (22.1) 790 (20.1) 328 (28.7) <.0001 SD: Standard deviation, CVA/TIA: cerebrovascular accident/transient ischemic attack, PAD: peripheral artery disease, BP: blood pressure, ACEI: angiotensin converting enzyme inhibitors, ARB: angiotensin receptor blockers, PCI: percutaneous coronary intervention, UA: unstable angina, CABG: coronary artery bypass graft, STEMI: ST-elevation myocardial infarction, NSTEMI: non–ST-elevation myocardial infarction, CHF: congestive heart failure, re-MI: remyocardial infarction. Table 2 In-hospital medications and clinical outcome comparisons. Comparing baseline characteristics, in-hospital treatment, and outcomes in women and men who were admitted with STEMI. Variables Overall n=2099 n (%) Male N=1772( 45.2) Female N=327 (28.6) P value Age (mean [SD]) 58.01 (12.9) 56.7 (12.9) 62.5 (11.9) <.001 Clinical features on presentation Systolic BP≤90 148 (3.2) 116 (3.3) 32 (3.0) .72 Heart rate≥100 679 (14.9) 468 (13.3) 211 (20.2) <.001 In-hospital treatment Aspirin 2061 (98.4) 1738 (98.3) 323 (98.8) .53 Clopidogrel 1681 (80.2) 1420 (80.3) 261 (79.8) .83 β-blocker 1628 (77.7) 1388 (78.5) 240 (73.4) .04 ACEI 1560 (74.5)) 1316 (74.4) 244 (74.6) .94 ARB 45 (2.1) 37 (2.1) 8 (2.4) .68 Statin 1937 (92.5) 1640 (92.8) 297 (90.8) .22 Thrombolysis 1152 (60.6) 994 (61.3) 158 (56.4) .10 Primary PCI 425 (8.4) 332 (8.5) 93 (8.1) .51 DNT (median, IQR) 52 (55) 52 (64) 71 (100) .035 In-hospital outcomes Recurrent ischemia 318 (15.2) 259 (14.6) 59 (18) .11 Re-MI 49 (2.3) 37 (2.1) 12 (3.7) .08 Death 95 (5.4) 59 (3.3) 36 (11) <.001 CHF 240 (11.4) 174 (9.8) 66 (20.2) <.001 Cardiogenic shock 158 (7.5) 122 (6.9) 36 (11) .01 Major bleeding 27 (1.3) 22 (1.2) 5 (1.5) .67 Stroke 30 (1.4) 22 (1.2) 8 (2.4) .09 SD: Standard deviation, BP: blood pressure, ACEI: angiotensin converting enzyme inhibitors, ARB: angiotensin receptor blockers, PCI: percutaneous coronary intervention, STEMI: ST-elevation myocardial infarction, CHF: congestive heart failure, re-MI: remyocardial infarction, DNT: door-to-needle-time.. Table 3 In-hospital mortality by ACS type. Variable OR 95% CI Age-adjusted OR 95% CI P value STEMI 3.5 2.3–5.5 2.5 1.5–3.8 <.001 NSTEMI 2.0 1.2–3.5 1.5 0.97–2.9 .06 ACS: Acute coronary syndrome, STEMI: ST-elevation myocardial infarction, NSTEMI: non–ST-elevation myocardial infarction, OR: odds ratio, CI: confidence interval. Table 4 Age-adjusted odds ratio (OR)and 95% confidence interval for hospital mortality in women compared to men with ACS in Saudi Arabia for those admitted with STEMI. Confounder adjusted for Adjusted OR P value Risk factors (age, diabetes mellitus, hypertension, dyslipidemia, CAD, smoking, PCI, and CABG) 2 (1.2–3) .003 Treatment (aspirin, β-blocker, ACE I, ARB, clopidogrel, statin, and thrombloytic) 2.5 (1.4–4.2) .001 Age, risk factors, and treatments 2 (1.1–3.4) .017 Age, risk factors, treatments, and DNT 2 (0.7–5.5) .14 PCI: Percutaneous coronary intervention, CABG: coronary artery bypass graft, CAD: coronary artery disease, ACEI: angiotensin converting enzyme inhibitors, ARB: angiotensin receptor blockers, STEMI: ST-elevation myocardial infarction, DNT: door-to- needle time. ==== Refs REFERENCES 1 Rosengren A Wallentin L Gitt KA Behar S Battler A Hasdai D Sex, age, and clinical presentation of acute coronary syndromes Eur Heart J 2004 4 25 8 663 70 15084371 2 Goldberg R Goff D Cooper L Luepker R Zapka J Bittner V Age and sex differences in presentation of symptoms among patients with acute coronary disease: the REACT Trial. Rapid Early Action for Coronary Treatment Coron Artery Dis 2000 11 399 407 10895406 3 DeVon HA Zerwic JJ Symptoms of acute coronary syndromes: are there gender differences? A review of the literature Heart Lung 2002 31 235 45 12122387 4 Patel H Rosengren A Ekman I Symptoms in acute coronary syndromes: does sex make a difference? Am Heart J 2004 148 27 33 15215788 5 Kosuge M Kimura K Ishikawa T Ebina T Hibi K Tsukahara K Differences between men and women in terms of clinical features of ST-segment elevation acute myocardial infarction Circ J 2006 70 222 6 16501283 6 Goldberg RJ McCormick D Gurwitz JH Yarzebski J Lessard D Gore JM Age-related trends in short- and long-term survival after acute myocardial infarction: a 20-year population-based perspective (1975–1995) Am J Cardiol 1998 82 11 1311 7 9856911 7 Norris C Dasgupta K Kirkland S Differences in cardiovascular presentation in women and men CMAJ 2007 176 6 S22 3 8 Rosengren A Spetz CL Köster M Hammar N Alfredsson L Rosén M Sex differences in survival after myocardial infarction in Sweden; data from the Swedish National Acute Myocardial Infarction Register Eur Heart J 2001 22 314 22 11161950 9 DeVon HA Zerwic JJ The symptoms of unstable angina: do women and men differ? Nurs Res 2003 52 108 18 12657986 10 Ayanian JZ Epstein AM Differences in the use of procedures between women and men hospitalized for coronary heart disease N Engl J Med 1991 325 221 5 2057022 11 Steingart RM Packer M Hamm P Coglianese ME Gersh B Geltman EM Sex differences in the management of coronary artery disease. Survival and Ventricular Enlargement Investigators N Engl J Med 1991 325 226 30 2057023 12 Vaccarino V Rathore SS Wenger NK Frederick PD Abramson JL Barron HV Sex and racial differences in the management of acute myocardial infarction, 1994 through 2002 N Engl J Med 2005 353 671 82 16107620 13 Mehilli J Kastrati A Dirschinger J Pache J Seyfarth M Blasini R Sex-based analysis of outcome in patients with acute myocardial infarction treated predominantly with percutaneous coronary intervention JAMA 2002 287 210 5 11779263 14 Mark DB Shaw LK DeLong ER Califf RM Pryor DB Absence of sex bias in the referral of patients for cardiac catheterization N Engl J Med 1994 330 1101 6 8133852 15 Raine RA Black NA Bowker TJ Wood DA Gender differences in the management and outcome of patients with acute coronary artery disease J Epidemiol Community Health 2002 56 791 7 12239207 16 AlHabib KF Hersi A AlFaleh H Kurdi M Arafah M Youssef M The Saudi Project for Assessment of Coronary Events (SPACE) registry: design and results of a phase I pilot study Can J Cardiol 2009 7 25 7 e255 8 19584982 17 Alhabib KF Hersi A Alfaleh H Alnemer K Alsaif S Taraben A Baseline characteristics, management practices, and in-hospital outcomes of patients with acute coronary syndromes: Results of the Saudi project for assessment of coronary events (SPACE) registry J Saudi Heart Assoc 2011 10 23 4 233 9 23960654 18 Elsaesser A Hamm CW Acute coronary syndrome: the risk of being female Circulation 2004 109 565 7 14769676 19 Canto JG Goldberg RJ Hand MM Bonow RO Sopko G Pepine CJ Symptom presentation of women with acute coronary syndromes: myth vs reality Arch Intern Med 2007 12 10 167 22 2405 13 18071161 20 Arslanian-Engoren C Patel A Fang J Armstrong D Kline-Rogers E Duvernoy CS Symptoms of men and women presenting with acute coronary syndromes Am J Cardiol 2006 11 1 98 9 1177 81 17056322 21 Hochman JS Tamis JE Thompson TD Weaver WD White HD Van de Werf F Sex, clinical presentation, and outcome in patients with acute coronary syndromes. Global Use of Strategies to Open Occluded Coronary Arteries in Acute Coronary Syndromes IIb Investigators N Engl J Med 1999 341 226 32 10413734 22 Hochman JS McCabe CH Stone PH Becker RC Cannon CP DeFeo-Fraulini T Outcome and profile of women and men presenting with acute coronary syndromes: a report from TIMI IIIB. TIMI Investigators. Thrombolysis in Myocardial Infarction J Am Coll Cardiol 1997 30 141 8 9207635 23 Hasdai D Porter A Rosengren A Behar S Boyko V Battler A Effect of gender on outcomes of acute coronary syndromes Am J Cardiol 2003 91 1466 9 12804736 24 Shaw LJ Miller DD Romeis JC Kargl D Younis LT Chaitman BR Gender differences in the non-invasive evaluation and management of patients with suspected coronary artery disease Ann Intern Med 1994 120 559 66 8116993 25 Bearden D Allman R Mcdonald R Miller S Pressel S Petrovitch H Age, race, and gender variation in the utilization of coronary artery bypass surgery and angioplasty in SHEP. SHEP Cooperative Research Group. Systolic Hypertension in the Elderly Program J Am Geriatr Soc 1994 42 1143 9 7963199 26 Kostis JB Wilson AC O’Dowd K Gregory P Chelton S Cosgrove NM Sex differences in the management and long-term outcome of acute myocardial infarction. A statewide study. Myocardial Infarction Data Acquisition System Circulation 1994 90 1715 30 7923655 27 Parving HH Lehnert H Bröchner-Mortensen J Gomis R Andersen S Arner P Irbesartan in Patients with Type 2 Diabetes and Microalbuminuria Study Group The effect of irbesartan on the development of diabetic nephropathy in patients with type 2 diabetes N Engl J Med 2001 345 870 8 11565519 28 Lewis EJ Hunsicker LG Clarke WR Berl T Pohl MA Lewis JB Renoprotective effect of the angiotensin-receptor antagonist irbesartan in patients with nephropathy due to type 2 diabetes N Engl J Med 2001 345 851 60 11565517 29 Bell DM Nappi J Myocardial infarction in women: a critical appraisal of gender differences in outcomes Pharmacotherapy 2000 9 20 9 1034 44 10999494 30 Maynard C Litwin PE Martin JS Weaver WD Gender differences in the treatment and outcome of acute myocardial infarction. Results from the Myocardial Infarction Triage and Intervention Registry Arch Intern Med 1992 152 972 6 1580724 31 Puletti M Sunseri L Curione M Erba SM Borgia C Acute myocardial infarction: sex related differences in prognosis Am Heart J 1984 108 63 6 6731284 32 Weaver WD White HD Wilcox RG Aylward PE Morris D Guerci A Comparisons of characteristics and outcomes among women and men with acute myocardial infarction treated with thrombolytic therapy. GUSTO-I investigators JAMA 1996 275 777 82 8598594 33 Redberg RF Gender differences in acute coronary syndrome: invasive versus conservative approach Cardiol Rev 2006 14 299 302 17053377 34 Kanamasa K Ishikawa K Hayashi T Hoshida S Yamada Y Kawarabayashi T Increased cardiac mortality in women compared with men in patients with acute myocardial infarction Intern Med 2004 43 911 8 15575239 35 Marrugat J García M Elosua R Aldasoro E Tormo MJ Zurriaga O Short-term (28 days) prognosis between genders according to the type of coronary event (Q-wave versus non–Q-wave acute myocardial infarction versus unstable angina pectoris) Am J Cardiol 2004 94 1161 5 15518611 36 El-Menyar A Zubaid M Rashed W Almahmeed W Al-Lawati J Sulaiman K Comparison of men and women with acute coronary syndrome in six Middle Eastern countries Am J Cardiol 2009 104 1018 22 19801017 37 Weintraub WS Wenger NK Kosinski AS Douglas JS Jr Liberman HA Morris DC Percutaneous transluminal coronary angioplasty in women compared with men J Am Coll Cardiol 1994 24 81 90 8006286 38 Bell MR Grill DE Garratt KN Berger PB Gersh BJ Holmes DR Jr Long-term outcome of women compared with men after successful coronary angioplasty Circulation 1995 91 2876 81 7796495