Coffee and coronary heart disease

Background: The role of coffee consumption in the onset of myocardial infarction remains uncertain. A review of published reports showed that although cohort data suggest very little excess risk of coronary heart disease among habitual coffee drinkers, case-control data suggest an excess risk of the order of 60% for people drinking five or more cups per day. Methods: We obtained as much information as possible on the lifestyle and habits, including coffee consumption, of people admitted with chest pain to the Coronary Care Unit at the Royal Perth Hospital, Australia. A questionnaire was given to them by the attending nursing staff. Details were recorded by the patient, often with help from the nursing staff. A similar questionnaire was completed by patients attending the Cardiology Outpatient Clinic. Results: One of the outstanding differences between the 182 patients with myocardial infarction or unstable angina and 185 patients with chronic stable coronary heart disease who filled in forms while waiting in the Cardiology Outpatient Clinic was that more people with acute coronary syndromes were drinking in excess of five cups of coffee per day (18 vs 7.5%; P = 0.003). In logistic regression analysis adjusted for age, smoking status (past and current), hypertension, dyslipidaemia and diabetes, the odds ratio was 2.51 (95% CI 1.43,4.43; P = 0.021). Conclusion: The present case-control study provides evidence for an increased risk of myocardial infarction or unstable angina among individuals drinking more than five cups of coffee per day.