clinical & basic research Sultan Qaboos University Med J, February 2013, Vol. 13, Iss. 1, pp. 43-50, Epub. 27th Feb 13 Submitted 24TH Apr 12 Revision Req. 31ST Jul 12, Revision recd. 1ST Aug 12 Accepted 2ND Sep 12 1Department of Non-communicable Diseases Surveillance & Control, Ministry of Health, Muscat, Oman; 2Department of Cardiology, Royal Hospital, Muscat, Oman *Corresponding Author e-mail: jallawati@gmail.com وبائيات متالزمة الشريان التاجي احلادة يف سلطنة عمان نتائج دراسة عمان- ريس جواد اأحمد اللواتي، كاظم جعفر �صليمان، برا�صانت بندوغرا مت التي البيانات حتليل املنهجية: عمان. �صلطنة يف احلادة التاجي ال�رسيان ملتالزمة اخلطر وعوامل وبائية تقييم الهدف: امللخ�ص: جمعها من خالل درا�صة متعددة املراكز يف عدة دول، بني املر�صى اللذين اأدخلوا على التوايل اىل امل�صايف والذين ترتاوح اأعمارهم 20 والإمارات وقطر والكويت والبحرين )عمان العربي اخلليج دول من خم�ض يف احلادة التاجي ال�رسيان متالزمة بت�صخي�ض اأكرث اأو عاما العربية املتحدة(، واليمن على مدى فرتة 5 اأ�صهر. هذا التحليل يلخ�ض بيانات املر�صى العمانيني الذين اأدخلوا امل�صت�صفى بت�صخي�ض مبدئي مبتالزمة ال�رسيان التاجي احلادة. النتائج: مت تاأكيد 1,340 حالة ملتالزمة ال�رسيان التاجي احلادة منها 748 بني الرجال 592 بني الن�صاء حيث بلغ العمر الو�صيط 61 �صنة. وكان معدل الإ�صابة للمتالزمة 338.9 حالة لكل 100,000 �صخ�ض- �صنة. بينما بلغت 779 و 674 حالة لكل100,000 �صخ�ض- �صنة بني الرجال والن�صاء على التوايل. وكان ن�صبة الذكور اإىل الإناث اأعلى بني مر�صى اإرتفاع مقطع ST )فى ر�صم قلب الإحت�صاء التجلطى )2.26، بفا�صل ثقة %95 1.63 اىل 3.15( ويليه اإحت�صاء ع�صلة القلب غري املرتبط مبقطع ST و�صكلت اىل 0.99(. 0.66 ثقة 95% بفا�صل 0.79( امل�صتقرة غري ال�صدرية والذبحة ،)2.21 اىل 1.28 ثقة 95% بفا�صل ،86.1 الذبحة ال�صدرية غري امل�صتقرة %55 من احلالت، واإحت�صاء ع�صلة القلب الناجم عن ارتفاع مقطع ST %26 واإحت�صاء ع�صلة القلب غري الدم �صغط ارتفاع انت�صار معدل التاجيزيادة ال�رسيان مبتالزمة خطرالأ�صابة عوامل بني من احلالت. من ST 19% مبقطع املرتبط )%68( وداء ال�صكري )%36(، وارتفاع الدهون )%63( وزيادة الوزن / ال�صمنة )%65(، مع معدل منخف�ض ن�صبيا من ا�صتخدام التبغ يف الوقت احلا�رس )%11( واخلال�صة: درا�صتنا توؤكد حدوث معدلت مرتفعة ملتالزمة ال�رسيان التاجي احلادة بني العمانيني ويدعم فكرة اأن وباء مر�ض القلب والأوعية الدموية جتتاح البلدان النامية. مفتاح الكلمات: متالزمة ال�رسيان التاجي احلادة، اأمرا�ض القلب والأوعية الدموية، نق�ض تروية القلب، عوامل اخلطر، و�صلطنة عمان. abstract: Objectives: This study aimed to evaluate the epidemiology and coronary risk factors of acute coronary syndrome (ACS) in Oman. Methods: Data were collected through a prospective, multinational, multicentre survey of consecutive patients, hospitalised over a 5-month period in 2007 with a diagnosis of ACS, in Yemen and five Arabian Gulf countries (Oman, Bahrain, Kuwait, Qatar, United Arab Emirates). Here we present data of Omani patients aged ≥20 years who received a provisional diagnosis of ACS and were consequently admitted to 14 different hospitals. Results: There where 1,340 confirmed ACS episodes in 748 men and 592 women (median age 61 years). The overall crude incidence rate of ACS was 338.9 per 100,000 person-years (P-Y). The age-standardised rate (ASR) of ACS was 779 and 674 per 100,000 P-Y for men and women, respectively. The ASR male-to-female rate ratio was highest in the ST-elevation myocardial infarction (STEMI) group (2.26, 95% confidence interval ([CI], 1.63 to 3.15) followed by the non-STEMI (NSTEMI) group (1.68, 95% CI 1.28 to 2.21) and unstable angina (0.79, 95% CI 0.66 to 0.99). Unstable angina accounted for 55%, STEMI for 26% and NSTEMI for 19% of ACS cases. Among the coronary risk factors, there was a high prevalence of hypertension (68%), diabetes mellitus (DM) (36%), hyperlipidaemia (63%), and overweight/obesity (65%), with a relatively low rate of current tobacco use (11%). Conclusion: Our study confirms a high incidence of ACS in Omanis and supports the notion that the cardiovascular disease epidemic is also sweeping developing countries. Keywords: Acute coronary syndrome; Incidence; Cardiovascular disease; Ischemic heart disease; Risk factors; Oman. The Epidemiology of Acute Coronary Syndrome in Oman Results from the Oman-RACE study *Jawad Al-Lawati,1 Kadhim Sulaiman,2 Prashanth Panduranga2 Advances in knowledge - This paper provides nationwide population-based incidence rates of acute coronary syndrome in a large prospective cohort recruited from multiple centres in Oman. - A comparable methodology was used, assessing the Omani population against other Arab Gulf states, and based upon an international comparison with other Arab, Asian, and European populations. The Epidemiology of Acute Coronary Syndrome in Oman Results from the Oman-RACE study 44 | SQU Medical Journal, February 2013, Volume 13, Issue 1 Current evidence indicates that cardiovascular diseases (CVD) make the largest contribution to mortality in most developing countries.1 Of all CVD, ischaemic heart disease (IHD) is the single largest cause of death in such nations.2 Worldwide, IHD was the second and third leading cause of disability-adjusted life years lost in men and women in 2002, respectively.1 Although rates of IHD have fallen by up to 70% in the past three decades in some industrialised countries, it is likely to remain as the undisputed leading cause of death globally until the year 2030.2,3 Since the early 1990s, CVDs have been the leading cause of in-patient mortality in Oman.4 In 2006, IHD was Oman’s leading cause of morbidity and fourth cause of mortality among patients aged 45-60 years.5 Although clinical management patterns of acute coronary syndrome (ACS) have been reported in Oman,6 to the best of our knowledge, the epidemiology of IHD and/or ACS has not been studied. Through a joint collaborative effort, the Gulf Registry for Acute Coronary Events (Gulf RACE) was established in 2006 to study such events in five Arabian Gulf countries and Yemen.7 The aim of this registry was to estimate the incidence of ACS in the participating countries, the distribution of CVD risk factors among affected patients, and types and practice patterns for the management of ACS.7 This study details the epidemiology and coronary risk factors of ACS patients throughout Oman. Methods The Gulf Registry of Acute Coronary Events (Gulf RACE) study was organised as a prospective, multinational, multicentre survey of consecutive patients over 20 years-old who had been hospitalised with the final diagnosis of acute coronary syndrome (ACS) in Yemen and five Arabian Gulf countries— Oman, Bahrain, Kuwait, Qatar, and the United Arab Emirates (UAE)—over a period of 6 months. The pilot phase lasted throughout May 2006 and is described in detail elsewhere.7 Enrolment for the study itself commenced on 29 January 2007, and continued for 5 months. An attempt was made to include all admissions that had been given a provisional diagnosis of ACS with no exclusion criteria. Patients who were admitted for non-ACS causes to general wards but later developed ACS in hospital were also included in the study. Of the 16 requested centres (15 secondary and one tertiary care hospital, all with facilities to manage ACS patients), 14 participated in the registry and enrolled patients according to the survey’s inclusion criteria. The study thus covered at least 85% of the total population of Oman. Ethical approval for the study was granted by the national or institutional ethical bodies in all participating countries. During the study period, all recruiting hospitals managed their patients independently. However, patients were referred to Royal Hospital in Muscat, the capital of Oman, on an emergency basis for primary angiography and/or angioplasty. Study forms initiated in the parent institution, or secondary care hospital, were sent with patients during transfer to the Royal Hospital to complete data collection procedures and avoid duplicate reporting. All medical services, including ACS management, are provided free of charge to Omani nationals throughout government institutions in the country. Data collected included patient demographics, past medical history, provisional diagnosis on admission, final discharge diagnosis, clinical features at hospital presentation, electrocardiogram (ECG) findings, laboratory investigations, medications administered within 24 hours of admission and those prescribed on discharge, use of cardiac procedures and interventions, in- hospital outcomes, and in-hospital mortality. All management decisions were at the discretion of the treating physician. The external auditor visited 20% of the centres where filled forms and source documents (i.e. patients’ case notes) were inspected to verify that data collected in the case report form matched source documents. No attempt was made to validate the accuracy of discharge diagnosis of Application to Patient Care - With the recognition of the high incidence of acute coronary syndrome (ACS) in Oman, the government and public health authorities should give higher priority to the control of the underlying cardiovascular disease risk factors which are shown to be highly prevalent in Omani patients. Jawad Al-Lawati, Kadhim Sulaiman and Prashanth Panduranga Clinical and Basic Research | 45 the attending physician. Diagnosis of the different types of ACS and definitions of data variables were based on the American College of Cardiology clinical data standards published in December 2001.8 These definitions are based on clinical presentations, ECG findings, and cardiac biomarkers. The biomarkers were measured locally at each hospital’s laboratory using its own assays and reference ranges. Only two centres used troponin (T) as routine assays in the diagnosis of myocardial injury. Body mass index (BMI) was used to characterise overweight (BMI 25–29.9 Kg/m2) or obese patients (BMI ≥30 Kg/m2).9 A waist circumference ≥94 cm in males and ≥80 cm in females was considered abnormal. Diagnosis of diabetes mellitus (DM) was based on past diagnosis by a physician, intake of anti- diabetic medications, or post-admission fasting plasma glucose (FPG) values using the 1999 diagnostic criteria recommended by the World Health Organization (WHO).10 Hypertension was diagnosed if systolic and/or diastolic arterial blood pressure exceeded 130/85 mmHg, or if a patient was on anti-hypertensive medication. Subjects were classified as having high total cholesterol if fasting levels exceeded 5.2 mmol/L; hypertriglyceridaemia if levels exceeded 1.69 mmol/L, and/or abnormal levels of high density lipoproteins if levels were <1.04 in males and <1.29 mmol/L in females.11 Data were entered in Epi Info, Version 6 (Centers for Disease Control, Atlanta, Georgia, USA). Categorical variables were presented as a number of cases and percentages and compared using the chi- square test. The K-sample equality-of-medians test was used to examine differences between groups of median age. Incidence rates of coronary events were calculated from index episodes during the study period using the mid-year 2007 population estimates for Oman obtained from the Omani Ministry of National Economy.12 To facilitate comparisons with other published rates, age-standardised incidence rates (ASR) were calculated by direct method within 10-year bands for ages 20 years and above, using the world standard population.13 For comparisons with World Health Organization - Monitoring Trends and Determinants in Cardiovascular Disease (WHO-MONICA), MONICA age weights in the 5-year age bands for ages 35–64 years were used.14,15 A 95% confidence interval (CI) for ASR ratio (RR) was calculated using the standard error of the natural logarithm of the RRs.16 Observed differences were expressed as P values. A value of P <0.05 was considered statistically significant. Analyses were performed with Intercooled Stata, version 9.1 (Stata Corporation, Texas, USA) and Microsoft Excel 2003 (Microsoft Corporation, Redmond, Washington, USA). Completeness of data was 98% for all the analysed variables. Patients with a diagnosis of left bundle branch block (n = 9) were grouped with the ST-elevation myocardial infarction (STEMI) patients. Results The baseline characteristics of the ACS patients enrolled in the study are given in Table 1. Over the 153-day recruitment period, 1,340 cases of ACS were reported with complete core data. The median age of ACS patients was 61 years (males 60 years and females 61 years; P = 0.39). Among the risk factors, a high prevalence of hypertension (56%), DM (38.2%), and hyperlipidaemia (36.4%) was reported on admission. When fasting blood sugar, blood pressure, and total cholesterol were measured 24 hours post-admission, there was a significant increase in the detection of hypertension (56–69%; P <001) and hyperlipidaemia (36.4–63.3%, P <001). The prevalence of DM was around 32% using random blood sugar, and increased to 46% when using fasting plasma glucose levels in patients with STEMI (P <001). One-half to two-thirds of ACS patients were either overweight or obese according to WHO criteria.9 Current tobacco use was relatively low (11.1%). Of the total ACS patients, 741 (55.3%) were discharged from hospitals with unstable angina, 345 (25.7%) with non-ST elevation myocardial infarction (NSTEMI) and 254 (18.9%) with STEMI [Table 1]. Unstable angina was also the most common diagnosis across all 10-year age strata, followed by NSTEMI and STEMI. Patients with unstable angina and NSTEMI were also more likely to report a medical history of percutaneous coronary intervention, DM, hypertension, and hyperlipidaemia. On the other hand, STEMI patients were more likely to be current tobacco users. Women were more likely to present with unstable angina compared to men (54% versus 46%, P <03) [Table 2], while men were twice as likely to present with STEMI and NSTEMI compared to The Epidemiology of Acute Coronary Syndrome in Oman Results from the Oman-RACE study 46 | SQU Medical Journal, February 2013, Volume 13, Issue 1 women. Table 2 demonstrates the crude and ASR of incidence of ACS in Oman in patients aged 20 years and above, and in a subgroup aged 35– 64 years. The period of case ascertainment (5 months) encompassed 395,389 person-years (P-Y) of observations in 748 men and 592 women (all Omanis) with episodes of ACS. The overall crude incidence of ACS was 338.9 per 100,000 P-Y. The ASR of ACS was 779 and 674 per 100,000 P-Y for men and women, respectively. The ASR of ACS were significantly higher in men than women with Table 1: Baseline characteristics of patients admitted with acute coronary syndrome (Oman RACE study, 2006) Characteristic STEMI % (n = 254) NSTEMI % (n = 345) Unstable Angina % (n = 741) All % (n = 1,340) Median age (yrs) 61 61 61 61 Age groups 20–29 0.8 0.6 0.9 0.8 30–39 4.7 4.6 3.5 4.0 40–49 12.6 13.9 13.9 13.7 50–59 22.0 26.1 25.9 25.2 60–69 29.5 33.0 33.3 32.5 70+* 30.3 21.7 22.4 23.7 Men* 73 65 46.0 56.0 Medical history Angina pectoris* 30.3 52.2 60.9 52.8 MI 16.1 22.6 19.5 19.6 PCI* 3.9 9.0 9.1 8.0 CABG* 3.1 7.0 9.5 7.6 Aspirin use* 31.6 54.2 60.2 53.2 Current tobacco use* 23.6 12.5 6.2 11.1 Diabetes* 30.3 37.4 41.3 38.2 Hypertension* 39.4 55.6 61.8 56.0 Hyperlipidaemia* 23.2 35.6 41.3 36.4 Measurements 24 hours post-admission RBG ≥ 11.1 mmol/l 32.4 30.7 28.7 29.9 FBG ≥ 7.0 mmol/l* 46.0 41.9 30.7 36.5 Hypertension* 61.0 68.0 71.8 68.8 TC >5.2mmol/l 63.3 63.4 63.3 63.3 Abnormal HDL 51.6 57.3 57.7 56.4 Abnormal TG 33.5 30.1 36.8 34.4 BMI 25-29.9 Kg/m2 33.5 40.3 38.3 37.9 BMI ≥30 kg/m2 25.2 26.4 28.9 27.5 Abnormal WC (cm)* 43.7 57.2 66.1 59.8 STEMI = ST-elevation myocardial infarction; NSTEMI = non-ST elevation myocardial infarction; MI = myocardial infarction; PCI = percutaneous coronary intervention; CABG = coronary artery bypass graft; RBG = random blood glucose; FBG = fasting blood glucose; TC = total cholesterol; HDL = high density lipoprotein; TG = triglycerides; BMI = body mass index; WC = waist circumference. * = P < 0.05; Chi-square tests were utilised to examine the statistical significance of differences between the respective comparison groups with regards to the distribution of categorical variables. A K-sample equality-of-medians test was used to examine between group differences in median age. For cut-off points for each variable, see Methods section. Jawad Al-Lawati, Kadhim Sulaiman and Prashanth Panduranga Clinical and Basic Research | 47 a rate ratio of 1.16 (95% CI: 1.01 to 1.32). The male to female age-standardised incident rate ratio was highest in the STEMI group (2.26, 95% CI: 1.63 to 3.15) followed by the NSTEMI group at 1.68 (95% CI: 1.28 to 2.21) and that with unstable angina at 0.79. (95% CI: 0.66 to 0.99). When data were analysed in a subgroup aged 35–64 years for broad comparisons with the MONICA project cohort, there were 448 events in males and 350 events in females within 128,187 P-Y.14 Age-standardised ACS event incident rates were higher in men than in women in this age band with a rate ratio of 1.21 (95% CI: 1.01 to 1.45). Discussion We provide the first age-standardised population- based incidence rates of ACS and associated risk factors in Oman. The ASR of ACS in Omanis (men 779, women 674 per 100,000 P-Y) were similar to rates reported among Palestinian Arabs of Jerusalem (796 and 503 per 100,000 men and women P-Y, respectively).17 These incidence rates are markedly higher than those reported in industrialised nations such as Denmark (men 331 and women 137 per 100,000 P-Y), Greece (both genders 226 per 100,000 P-Y), and France (men 262 and women 55 per 100,000 P-Y), thus confirming the double burden of already existing communicable diseases and the present non-communicable diseases in Table 2: Crude and age-standardised annual incidence rates (all per 100,000 person-years) of acute coronary syndrome and its components in Omani men and women aged 20 years and above (Oman RACE study, 2006) Age group All ACS STEMI NSTEMI Unstable Angina Male (20+ years) No. of cases 748 184 224 340 P-Y 198,324 198,324 198,324 198,324 Crude rate (95% CI) 377.2 (350.6 to 405.1) 92.8 (79.9 to 107.2) 112.9 (98.6 to 128.8) 171.4 (153.7 to 190.6) ASR (95% CI) 779.7 (723.2 to 836.2) 184.9 (164.6 to 221.5) 239.5 (200.5 to 262.3) 355.3 (723.2 to 836.2) Female (20+ years) No. of cases 592 70 121 401 P-Y 197,065 197,065 197,065 197,065 All crude (95% CI) 300.4 (276.7 to 325.6) 35.5 (27.7 to 44.9) 61.4 (50.9 to 73.4) 203.5 (184.1 to 224.4) All ASR (95% CI) 674.3 (619.5 to 729.1) 81.7 (64.1 to 103.8) 142.2 (114.7 to 165.3) 450.4 (619.5 to 729.1) Male (35-64 years) No. of cases 448 139 103 206 Person-years 63,543 63,543 63,543 63,543 ASR for ages 35–64 835.0 (757.3 to 912.8) 189.7 (152.6 to 226.8) 256.9 (213.7 to 300.2) 388.3 (335.0 to 441.7) Females (35-64 yrs) No. of Cases 350 39 241 P-Y 64,644 64,644 64,644 64,644 ASR for ages 35–64 691.6 (618.7 to 764.5) 81.1 (55.5 to 106.7) 138.9 (106.0 to 171.7) 471.6 (411.4 to 531.7) Male:Female Rate ratio, 20+ years (95% CI) 1.16 (1.01 to 1.32) 2.26 (1.63 to 3.15) 1.68 (1.28 to 2.21) 0.79 (0.66 to 0.99) Rate ratio, 35–64 years (95% CI) 1.21 (1.01 to 1.45) 2.34 (1.47 to 3.73) 1.85 (1.28 to 2.68) 0.82 (0.65 to 1.05) ACS = acute coronary syndrome; STEMI = ST-elevation myocardial infarction; NSTEMI = Non ST-elevation myocardial infarction; P-Y = person-years; ASR = age-standardised rate; CI = confidence interval. For age-standardising, see reference no. 13. The Epidemiology of Acute Coronary Syndrome in Oman Results from the Oman-RACE study 48 | SQU Medical Journal, February 2013, Volume 13, Issue 1 middle and low-income developing countries.18– 21Notwithstanding the differences in the definitions of coronary events between the present study and the MONICA populations studied between 1981 and 1995, the coronary event incidence rate in Omani men aged 35–64 years (835 per 100,000 P-Y) are comparable to the highest rates recorded in the MONICA project (907 per 100,000 P-Y among Finnish men).22 Similarly, in the 35–64 year old cohort, the incidence rate of ACS among Omani women (692 per 100,000 P-Y) was more than double the rate in their Scottish counterparts in the UK (241 per 100,000 P-Y), although, the latter was the highest rate reported among MONICA women.22 When compared with other Arabs in the same age group of 35–64 years, the ACS incidence rate among Omanis surpassed the rate reported in Palestinian men (799 per 100,000 P-Y) while the rate in Omani women was three times the rate in Palestinian women (234 per 100,000 P-Y).17 The high incidence of ACS among Omanis (and other Arab ethnic groups) may stem from greater susceptibility and excess exposure to established CVD risk factors.23 In Asian populations, morbidity and mortality appear to occur at lower cut-off point values for some CVD risk factors such as BMI and waist circumference than in Caucasians, possibly indicating greater susceptibility at a lower threshold for adverse health outcomes.24–26 In our study, Omani patients appeared to experience ACS at an earlier age (mean 60.7 years; median 61 years) than their counterparts from Europe, Australia, the United States, and Brazil (median range 63.4– 68.1) by an average of 2 to 7 years.27The difference in age can extend up to 11 years if compared with Europeans with unstable angina.28 Arab patients with ACS from other countries were also reported to be younger (mean age: Saudi Arabia 57.1, Kuwait 56.7, and Palestine 57.9),17,29,30 The INTERHEART study also showed Arab patients to be a decade younger at presentation with acute myocardial infarction than Europeans, Chinese, or Latin American patients.31 The earlier onset of ACS in Arabs has not been studied systematically. However, greater susceptibility to CVD risk factors may be implied, in a similar way suspected to occur among South Asians through genetic differences or a mismatch of metabolic processes during early or middle age.23 Other findings like low levels of high density lipoproteins and a lack of regular physical activity among Omanis may have contributed further to their susceptibility to adverse coronary outcomes.32 Our study’s main strength lies in the fact that it is the first to provide nationwide estimates of incidence and risk factors of ACS in a large prospective cohort recruited from multiple centres in Oman using a methodology comparable with other Arab Gulf states. On the other hand, the lack of a vital registration system within the country implies that sudden cardiac deaths due to ACS could not be estimated and thus are not included in the current incidence estimates presented here. Further, due to limited resources, out of 1,340 patients, T assays were used in less than 21% (277 patients) to diagnose myocardial injury. However, this is unlikely to have biased results towards the under- diagnosis of STEMI and NSTEMI as proportions of the later two in Oman are similar (42% and 58%, respectively) to the overall Gulf-RACE (39% and 61%, respectively) and Gulf-RACE 2 (46% and 54%, respectively) studies after discarding results from unstable angina patients.33,34 Finally, comparison data were presented with MONICA cohorts in spite of changes of some diagnostic criteria and temporality between the two studies, mainly due to wide use of T assays in the current survey. Conclusion The incidence of ACS among Omanis is one of the highest in the world and flags up an impending CVD epidemic that is yet to reach its peak. The need to address root causes of established CVD risk factors could not be more urgent.35 Health reforms and prevention strategies are needed to counter a CVD epidemic, with a particular focus on reducing the high number of preventable risk factors. a c k n o w l e d g e m e n t s We would like to thank all patients who consented to this study. We thank all physicians who collaborated in the data collection and data management for this study. Without their collaboration this study would have not been possible. References 1. World Health Organization. The World Health Report 2003: Shaping the future. Geneva: World Jawad Al-Lawati, Kadhim Sulaiman and Prashanth Panduranga Clinical and Basic Research | 49 Health Organization 2003. 2. Mathers CD, Loncar D. Projections of global mortality and burden of disease from 2002 to 2030. PLoS Med 2006; 3:e442. 3. World Health Organization. Preventing chronic diseases: 2005: A vital investment. Geneva: World Health Organization 2005. 4. Hill AG, Muyeed AZ, Al-Lawati JA. The mortality and health transitions in Oman: patterns and processes. Cairo: World Health Organization Regional Office for the Eastern Mediterranean and UNICEF, 2000. 5. Directorate General of Planning, Ministry of Health, Oman. Annual Health Report, 2007. Muscat: Ministry of Health 2007. 6. Panduranga P, Sulaiman K, Al-Zakwani I. Acute coronary syndrome in Oman: Results from the Gulf registry of acute coronary events. Sultan Qaboos Univ Med J 2011; 11:338–42. 7. Zubaid M, Rashed WA, Al-Khaja N, Almahmeed W, Al-Lawati J, Sulaiman K, et al. Clinical presentation and outcomes of acute coronary syndromes in the Gulf Registry of Acute Coronary Events (Gulf RACE). Saudi Med J 2008; 29:251–5. 8. Cannon CP, Battler A, Brindis RG, Cox JL, Ellis SG, Every NR, et al. American College of Cardiology key data elements and definitions for measuring the clinical management and outcomes of patients with acute coronary syndromes. A report of the American College of Cardiology Task Force on Clinical Data Standards (Acute Coronary Syndromes Writing Committee). J Am Coll Cardiol 2001; 38:2114–30. 9. World Health Organization. Obesity: Preventing and managing the global epidemic. World Health Organization (WHO Technical Report Series, No. 894). Geneva: World Health Organization, 2000. 10. World Health Organization. Definition, diagnosis and classification of diabetes mellitus and its complications. Part 1: diagnosis and classification of diabetes mellitus. Report of a WHO consultation. Geneva: World Health Organization, 1999. WHO/ NCD/NCS/99.2. 11. National Cholesterol Education Program. Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) final report. Circulation 2002; 106:3143-421. 12. Directorate General of Planning. Annual health report. Muscat: Ministry of Health, 2007. 13. Segi M. Cancer mortality for selected sites in 24 countries (1950–57). Sendai, Japan: Tohoku University School of Medicine, Department of Public Health, 1960. 14. Tunstall-Pedoe H, Kuulasmaa K, Mahonen M, Tolonen H, Ruokokoski E, Amouyel P. Contribution of trends in survival and coronary-event rates to changes in coronary heart disease mortality: 10- year results from 37 WHO MONICA project populations. Monitoring trends and determinants in cardiovascular disease. Lancet 1999; 353:1547–57. 15. Mahonen M, Tolonen H, Kuulasmaa K. MONICA Coronary Event Registration Data Book 1980-1995, October 2000. From: http://www.ktl.fi/publications/ monica/coredb/coredb.htm Accessed: Oct 2009. 16. Breslow NE, Day NE, Eds. Statistical methods in cancer research. Vol II. The design and analysis of cohort studies. International Agency for Research on Cancer. Lyon, France: International Agency for Research on Cancer, Scientific Publication No. 82, 1987. P. 64. 17. Kark JD, Fink R, Adler B, Goldberger N, Goldman S. The incidence of coronary heart disease among Palestinians and Israelis in Jerusalem. Int J Epidemiol 2006; 35:448–57. 18. Nielsen KM, Foldspang A, Larsen ML, Gerdes LU, Rasmussen S, Faergeman O. Estimating the incidence of the acute coronary syndrome: Data from a Danish cohort of 138,290 persons. Eur J Cardiovasc Prev Rehabil 2007; 14:608–14. 19. Pitsavos C, Panagiotakos DB, Antonoulas A, Zombolos S, Kogias Y, Mantas Y, et al. Epidemiology of acute coronary syndromes in a Mediterranean country: Aims, design and baseline characteristics of the Greek study of acute coronary syndromes (GREECS). BMC Public Health 2005; 5:23. 20. Ferrieres J, Cambou JP. Epidemiology of acute coronary syndrome in France. Ann Cardiol Angeiol (Paris) 2007; 56:S8–15. 21. Boutayeb A. The double burden of communicable and non-communicable diseases in developing countries. Trans R Soc Trop Med Hyg 2006; 100:191–9. 22. Tunstall-Pedoe H, Kuulasmaa K, Amouyel P, Arveiler D, Rajakangas AM, Pajak A. Myocardial infarction and coronary deaths in the World Health Organization MONICA Project. Registration procedures, event rates, and case-fatality rates in 38 populations from 21 countries in four continents. Circulation 1994; 90:583–612. 23. Bhopal R. Epidemic of cardiovascular disease in South Asians. BMJ 2002; 324:625–6. 24. World Health Organization Western Pacific Region. The Asia-Pacific Perspective: Redefining Obesity and its Treatment. Geneva: World Health Organization 2000. 25. Kanazawa M, Yoshiike N, Osaka T, Numba Y, Zimmet P, Inoue S. Criteria and classification of obesity in Japan and Asia-Oceania. Asia Pac J Clin Nutr 2002; 11:S732–7. 26. Deurenberg-Yap M, Yian TB, Kai CS, Deurenberg P, Staveren WA. Manifestation of cardiovascular risk factors at low levels of body mass index and waist- to-hip ratio in Singaporean Chinese. Asia Pac J Clin Nutr 1999; 8:177–83. The Epidemiology of Acute Coronary Syndrome in Oman Results from the Oman-RACE study 50 | SQU Medical Journal, February 2013, Volume 13, Issue 1 27. Goldberg RJ, Currie K, White K, Brieger D, Steg PG, Goodman SG, et al. Six-month outcomes in a multinational registry of patients hospitalized with an acute coronary syndrome (the Global Registry of Acute Coronary Events (GRACE). Am J Cardiol 2004; 93:288–93. 28. Hasdai D, Behar S, Wallentin L, Danchin N, Gitt AK, Boersma E, et al. A prospective survey of the characteristics, treatments and outcomes of patients with acute coronary syndromes in Europe and the Mediterranean basin; the Euro Heart Survey of Acute Coronary Syndromes (Euro Heart Survey ACS). Eur Heart J 2002; 23:1190–201. 29. AlHabib KF, Hersi A, AlFaleh H, Kurdi M, Arafah M, Youssef M, et al. The Saudi Project for Assessment of Coronary Events (SPACE) registry: Design and results of a phase I pilot study. Can J Cardiol 2009; 25:e255–8. 30. Zubaid M, Suresh CG, Thalib L, Rashed W. Differential distribution of risk factors and outcome of acute coronary syndrome in Kuwait: Three years' experience. Med Princ Pract 2004; 13:63–8. 31. Yusuf S, Hawken S, Ounpuu S, Dans T, Avezum A, Lanas F, et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): Case-control study. Lancet 2004; 364:937–52. 32. Al-Lawati JA, Mohammed AJ, Al-Hinai HQ, Jousilahti P. Prevalence of the metabolic syndrome among Omani adults. Diabetes Care 2003; 26:1781– 5. 33. Zubaid M, Rashed WA, Almahmeed W, Al-Lawati J, Sulaiman K, Al-Motarreb A, et al. Management and outcomes of Middle Eastern patients admitted with acute coronary syndromes in the Gulf Registry of Acute Coronary Events (Gulf RACE). Acta Cardiol 2009; 64:439–46. 34. Alhabib KF, Sulaiman K, Al-Motarreb A, Almahmeed W, Asaad N, Amin H, et al. Baseline characteristics, management practices, and long-term outcomes of Middle Eastern patients in the Second Gulf Registry of Acute Coronary Events (Gulf RACE-2). Ann Saudi Med 2012; 32:9–18. 35. Al-Lamki L. Acute coronary syndrome, diabetes and hypertension: Oman must pay more attention to chronic non-communicable diseases. Sultan Qaboos Unv Med J 2011; 11:318–21.