CORRECTION FOR BIASES IN A POPULATION-BASED STUDY OF FAMILY HISTORY AND CORONARY HEART-DISEASE - THE NEWCASTLE-FAMILY-HISTORY-STUDY-II

The authors carried out a population-based case-control study to estim ate the risk of an acute coronary disease event associated with variou s definitions of a family history of coronary heart disease (CHD). A d etailed family history questionnaire was completed by 403 cases and 23 6 controls in Newcastle, New South Wales; Australia from 1992 to 1994. Odds ratios of an-acute coronary disease event adjusted for proband a ge and sex ranged from 2.7 (95% confidence interval (CI) 1.8-4.1) for the simplest definition (one or more first-degree relatives with CHD a t any age) to 5.4 (95% CI 1.7-16.8) for the most stringent definition (two or more first-degree relatives with CHD before age 55 years). In a series of nested models, the authors examined the improvement in mod el fit as each component of the detailed family history was added. Add itional information was provided by accounting for ''don't know'' resp onses, the number of affected relatives, the age of the affected relat ive, and whether the first-degree relative was a sibling rather than a parent. The results were similar when the data were analyzed as a coh ort design with proband disease status as the exposure variable. The a uthors suggest that, to facilitate preventive efforts in a population, more detailed family history definitions should be used to better tar get high risk subjects.