SUMMARYValues for several coronary risk factors, including systolic and diastolic blood pressure, serum cholesterol, triglycerides, blood glucose, uric acid, hemoglobin, weight, vital capacity and cigarette smoking have been found to be similar among spouses in the Framingham Study. However, longitudinal analyses show that this spouse concordance does not increase over a twelve-year observation period, suggesting that it has arisen through the marriage of similar people rather than through the sharing of a common marital environment. Apparent conflicts between cross-sectional and longitudinal findings have been resolved by showing that spouses who were concordant at the beginning of the study are more likely to survive to later exams, while discordant spouse pairs tend to be dissolved through the death of one of their members.CLINICIANS, epidemiologists, and other students of human biology share an interest in studies of family clusters of heart disease and its antecedents. The recent inclusion of husband and wife pairs (spouse pairs) has added a new dimension to earlier studies of first-degree relatives. Not only do spouse analyses assist in teasing out the relative contribution of genetic and environmental factors, but such studies, if a positive association is found, might provide a rationale both for case-finding and for environmental modification.Previous studies of spouse concordance* for coronary risk factors have been summarized elsewhere.' In brief, the majority2-7-but by no means all8-' -of these investigations have shown spouse concordance for blood pressure which is greater than chance; occasionally, this concordance approached or equalled that found among first-degree relatives. Furthermore, 27, 1975. this spouse concordance was frequently observed to increase in direct proportion to the duration of marriage, suggesting a cumulative effect of the common marital environment.Attempts to identify and measure spouse concordance for coronary risk factors face three difficult methodologic problems which warrant brief consideration here. First, because many coronary risk factors change with aging -/nd since spouse pairs tend to be of roughly similar ages -spurious spouse concordance results unless some statistical procedure is introduced to "correct" for this age-related change. However, the standard procedures used to "correct" for age differences in coronary risk factors may not accomplish this goal; we found persistent, statistically significant age differences in most coronary risk factors among Framingham subjects when we used the classic correction procedures.3' 12The second methodologic problem arises when tests for statistical significance are applied to these agecorrected coronary risk factor values in order to detect concordance. Because the age-corrected values are only rarely normally distributed, they violate a basic assumption of the significance tests.' Again, we have found that application of the classic age-correction procedures to Framingham data produce values which are seldom normal...
