BACKGROUND Allergic rhinitis (AR), atopic dermatitis (AD), and asthma, each by itself, are known to be associated with a higher risk of cardiovascular disease. Each of these diseases often coexists with one another, but the effect of combined allergic diseases on the long-term risk of myocardial infarction (MI) and mortality remains unknown.

OBJECTIVE To evaluate the effects of various combinations of the allergic triad on the risk of MI and mortality.

METHODS Adult allergic disease patients without prior MI were enrolled from the nationwide health check-up data provided by the Korean National Health Insurance Service in 2009. The primary and secondary end points were all-cause death and MI.

RESULTS A total of 9,548,939 individuals older than 20 years were selected for analysis. The prevalence of allergic diseases was 13.9% for AR, 0.4% for AD, and 2.7% for asthma. During a median 8.2 years of follow-up, 105,659 MIs and 298,769 deaths occurred. All allergic diseases were associated with an increased risk of MI (AR, adjusted hazard ratio [HR_adjust], 1.11, 95% CI, 1.10-1.13; AD, HR_adjust, 1.14, 95% CI, 1.06-1.24; asthma, HR_adjust, 1.37, 95% CI, 1.33-1.40), whereas mortality risk was increased only for patients with AD (HR_adjust, 1.15; 95% CI, 1.10-1.20) or asthma (HR_adjust, 1.41; 95% CI, 1.39-1.43). Among the combinations of allergic diseases, patients with both AD and asthma had the highest risk of mortality (HR_adjust, 1.71; 95% CI, 1.46-2.00) and MI (HR_adjust, 1.57; 95% CI, 1.15-2.16). The results were significant after adjusting for demographic characteristics, comorbidities, socioeconomic status, and lifestyle factors.

CONCLUSIONS Patients with both AD and asthma have the highest risk of MI and mortality among all allergic disease combinations. Physicians should evaluate combinations of allergic conditions in allergic disease patients and promptly assess and manage their future risk of MI and mortality.