Increased Risk of Myocardial Infarction Associated With Angiotensin-Converting Enzyme Gene Polymorphism Is Age Dependent

The angiotensin-converting enzyme (ACE) gene is a candidate genetic locus for coronary artery disease (CAD). Studies investigating the relationship between the ACE-insertion/deletion (I/D) gene polymorphism and myocardial infarction (MI) have been inconsistent. The authors hypothesized that age may be an important modulating factor in this relationship. ACE-I/D allele and genotype distribution was determined in 3 groups: 104 men with a first MI at a young age (<= 45 years old), 271 healthy young men (<= 30 years old), and 28 healthy elderly men (>65 years old). All participants were French descendants from Quebec City, Canada. Frequency distribution of the ACE alleles and genotypes was similar among the healthy young, the healthy elderly, and the MI patients (P > .05). However, when considering the age at the time of the MI (<= 40, <= 35, or <= 30 years old), a significant age-dependent effect with the prevalence of the ACE-DD genotype was found, as it increased by 22%, 61%, and 157%, respectively, compared with the healthy young group (P < .05). Similar observations were obtained versus the healthy elderly men (P < .05). The ACE-I/D polymorphism seems to be a genetic risk factor for MI in young men and becomes an important modulator of MI risk at a young age.