Increased frequency of coronary heart disease in relatives of wives of myocardial infarct survivors: assortative mating for lifestyle and risk factors?

The frequency of myocardial infarction (MI) and coronary artery disease (CAD) was studied among the first-degree relatives of 126 spouses of male survivors of MI, and compared with the frequency of MI and CAD among relatives of 126 age-matched control subjects. MI and CAD were as frequent among the relatives of the wives as among the relatives of their husbands with MI. MI and CAD were less frequent among the relatives of control subjects. Familial aggregation of CAD, therefore, is not limited to patients' relatives, but also affects the wives' families. This finding can be explained by assortative mating, i.e., marriage partners choose mates with similar lifestyles and risk factors that lead to CAD.