a b s t r a c tContext: Elderly patients have more cardiovascular risk factors and a greater burden of ischemic disease than younger patients. Aims: To examine the impact of age on clinical presentation and outcomes in patients presenting with acute coronary syndrome (ACS). Methods and material: Collected data from the 2nd Gulf Registry of Acute Coronary Events (Gulf RACE-2), which is a prospective multicenter study from six adjacent Arab Middle Eastern Gulf countries. Patients were divided into 3 groups according to their age: 50 years, 51e70 years and >70 years and their clinical characteristics and outcomes were analyzed. Mortality was assessed at one and 12 months. Statistical analysis used: One-way ANOVA test for continuous variables, Pearson chi-square (X 2 ) test for categorical variables and multivariate logistic regression analysis for predictors were performed. Results: Among 7930 consecutive ACS patients; 2755 (35%) were 50 years, 4110 (52%) were 51e70 years and 1065 (13%) >70 years old. The proportion of women increased with increasing age (13% among patients 50 years to 31% among patients > 70 years). The risk factor pattern varied with age; younger patients were more often obese, smokers and had a positive family history of CAD, whereas older patients more likely to have diabetes mellitus, hypertension, and dyslipidemia. Advancing age was associated with under-treatment evidence-based therapies. Multivariate logistic regression analysis after adjusting for relevant covariates showed that old age was independent predictors for re-ischemia (OR 1.29; 95% CI 1.03e1.60), heart failure (OR 2.8; 95% CI 2.17e3.52) and major bleeding (OR 4.02; 95% CI 1.37 e11.77) and in-hospital mortality (age 51e70: OR 2.67; 95% CI 1.86e3.85, and age >70: OR 4.71; 95% CI 3.11e7.14). Conclusion: Despite being higher risk group, elderly are less likely to receive evidence-based therapies and had worse outcomes. Guidelines adherence is highly recommended in elderly.