The Risk Factors of Premature Myocardial Infarction: A Case Control Study in Iran

BACKGROUND: Although, our knowledge about the factors of cardio vascular diseases (CVD) is relatively acceptable, we have few publications about the risk factors of premature CVD particularly from developing countries such as Iran.

OBJECTIVES: The present study is aimed to assess the risk of the modifiable risk factors of coronary heart disease (CHD) in the first cardiac attack of patients classified by age to check which risk factors might have a more significant impact to increase the risk of premature myocardial infarction (MI).

METHODS: In a case control study, 122 and 266 cases and controls were recruited from one of the main referral centres in Tehran. Cases were those who were hospitalized because of their first myocardial infarction before the ages of 50 and 55 years in males and females respectively, and compared their risk factor profiles with those experienced first MI in higher age. Main independent variables in this study were: the demographic variables, distress, lipid profile, diabetes, smoking, family history of cardio vascular diseases, and physical activity.

RESULTS: The results showed that distress (OR= 3.95), minorities (compare to Fars race) (OR= 3.30), higher education (OR= 1.30), family history of hyperlipidaemia (OR=1.89) significantly increased the risk of premature MI. We also found that family history of hypertension (OR=1.35), current smoking versus no smoking (OR=1.60), fast-food consumption (OR=1.48), non-alcoholic beverages (OR= 1.12) had also association with the risk of premature MI but only in crude model. We also found that regular physical activity (OR=0.42), ex-smoker versus current smoking (OR=0.27) and regular consumption of milk (OR=0.73) was protective against premature MI.

CONCLUSION: Our findings demonstrate that the effect of most of risk factors were mostly related to their life-style (distress, smoking, physical inactivity and dietary pattern); while family history of diseases was also important.