Coffee and tea consumption and the prevalence of coronary heart disease in men and women: results from the Scottish Heart Health Study.
STUDY OBJECTIVES--The aim was to determine if there was a relationship between coffee or tea consumption and the prevalence of coronary heart disease in Scotland. DESIGN--The relationship between self reported coffee and tea consumption and the prevalence of coronary heart disease (history, symptoms, or electrocardiographic evidence) was investigated using multiple logistic regression analysis in the Scottish Heart Health Study (SHHS), a cross sectional study. SETTING--Twenty two Scottish districts were surveyed for the SHHS between 1984 and 1986. SUBJECTS--A total of 10,359 men and women aged 40-59 years were studied. MEASUREMENTS AND MAIN RESULTS--Of the 9740 subjects who were assigned a category, 21.8% (2122) were classified as having indications of coronary heart disease. Men and women were combined in the odds ratio analysis because they showed almost identical patterns in the prevalence of coronary heart disease across the coffee and tea quarters (grouped according to consumption). Those who did not drink coffee had a significantly higher (p < 0.05) prevalence of coronary heart disease than the three groups for coffee drinkers. Adjustments for risk factors including cigarette smoking, total blood cholesterol, and diastolic blood pressure did not remove the significance of the odds ratios. There was a positive dose-response effect between tea consumption and coronary heart disease which was removed after adjustment for various risk factors. CONCLUSIONS--These findings do not support a positive relationship between coffee or tea consumption and coronary heart disease in this British study where most coffee consumed is instant coffee.