Although coronary heart disease (CHD) primarily occurs in patients over the age of 40, younger men and women can be affected. Most studies have used an age cut-off of 40 to 45 years to define "young" patients with CHD or acute myocardial infarction (MI). The same age definition will be used in this review.
The prevalence of CHD in younger subjects is difficult to establish accurately since it is frequently a silent process. The frequency with which this occurs was examined in an autopsy study of 760 young (age 15 to 34 years) victims of accidents, suicides, or homicides . Advanced coronary atheromata were seen in 2 percent of men and no women aged 15 to 19. An advanced lesion was present in 20 and 8 percent of men and women aged 30 to 34, respectively, while 19 and 8 percent, respectively, had a ≥40 percent stenosis of the left anterior descending artery.
There are also limited data on the frequency of MI in younger subjects. In the Framingham Heart Study, the incidence of an MI over a 10-year follow-up was 12.9/1000 in men 30 to 34 years old and 5.2/1000 in women 35 to 44 years old . The incidence of MI was eight to nine times greater in men and women aged 55 to 64 years. In other studies, 4 to 10 percent of patients with MI were ≤40 or 45 years of age [3-5]. In two series of patients with CHD at ≤40 years of age, women comprised 5.6 and 11.4 percent of patients [3,6].
Although CHD is an uncommon entity in young patients, it constitutes an important problem for the patient and the treating physician because of the devastating effect of this disease on the more active lifestyle of young patients. In addition, these patients have different risk factor profiles, clinical presentations, and prognoses than older patients. All of these factors should be taken into consideration when treating young patients with CHD.
A separate issue, acute MI during pregnancy, is discussed elsewhere. (See "Acute coronary syndromes in pregnancy".)