[HTML][HTML] Genetic susceptibility to death from coronary heart disease in a study of twins

ME Marenberg, N Risch, LF Berkman… - … England Journal of …, 1994 - Mass Medical Soc
ME Marenberg, N Risch, LF Berkman, B Floderus, U de Faire
New England Journal of Medicine, 1994Mass Medical Soc
Background A family history of premature coronary heart disease has long been thought to
be a risk factor for coronary heart disease. Using data from 26 years of follow-up of 21,004
Swedish twins born between 1886 and 1925, we investigated this issue further by assessing
the risk of death from coronary heart disease in pairs of monozygotic and dizygotic twins.
Methods The study population consisted of 3298 monozygotic and 5964 dizygotic male
twins and 4012 monozygotic and 7730 dizygotic female twins. The age at which one twin …
Background
A family history of premature coronary heart disease has long been thought to be a risk factor for coronary heart disease. Using data from 26 years of follow-up of 21,004 Swedish twins born between 1886 and 1925, we investigated this issue further by assessing the risk of death from coronary heart disease in pairs of monozygotic and dizygotic twins.
Methods
The study population consisted of 3298 monozygotic and 5964 dizygotic male twins and 4012 monozygotic and 7730 dizygotic female twins. The age at which one twin died of coronary heart disease was used as the primary independent variable to predict the risk of death from coronary heart disease in the other twin. Information about other risk factors was obtained from questionnaires administered in 1961 and 1963. Actuarial life-table analysis was used to estimate the cumulative probability of death from coronary heart disease. Relative-hazard estimates were obtained from a multivariate survival analysis.
Results
Among the men, the relative hazard of death from coronary heart disease when one's twin died of coronary heart disease before the age of 55 years, as compared with the hazard when one's twin did not die before 55, was 8.1 (95 percent confidence interval, 2.7 to 24.5) for monozygotic twins and 3.8 (1.4 to 10.5) for dizygotic twins. Among the women, when one's twin died of coronary heart disease before the age of 65 years, the relative hazard was 15.0 (95 percent confidence interval, 7.1 to 31.9) for monozygotic twins and 2.6 (1.0 to 7.1) for dizygotic twins. Among both the men and the women, whether monozygotic or dizygotic twins, the magnitude of the relative hazard decreased as the age at which one's twin died of coronary heart disease increased. The ratio of the relative-hazard estimate for the monozygotic twins to the estimate for the dizygotic twins approached 1 with increasing age. These relative hazards were little influenced by other risk factors for coronary heart disease.
Conclusions
Our findings suggest that at younger ages, death from coronary heart disease is influenced by genetic factors in both women and men. The results also imply that the genetic effect decreases at older ages. .
The New England Journal Of Medicine