A number of inflammatory diseases have been associated with an increased risk of atherosclerosis. Knoflach and colleagues report findings that support a link between allergic diseases, such as allergic rhinitis and asthma, and atherosclerosis. Their findings came from 2 studies: the Bruneck study, which included 826 men and women aged 40 to 70 years, and the Atherosclerosis Risk Factors in Male Youngsters (ARMY) study, which included 141 male participants aged 17 or 18 years.
In the ARMY study, the persons with allergic rhinitis or asthma had an increased risk of high intima-media thickness, as assessed by ultrasonography (odds ratio [OR], 2.5). In the Bruneck study, participants with such allergic diseases were at increased risk for the development and progression of atherosclerosis (OR, 3.8); these findings were confirmed when IgE levels were substituted for the clinical allergy variable (adjusted OR, 1.7). However, IgE was not associated with allergy in the ARMY study.
The authors discuss 2 possible explanations for their findings. First, allergy may be a true risk factor for atherosclerosis, an idea that is supported by what is known about the systemic inflammatory response. Second, allergy and atherosclerosis may share central effector pathways and certain predisposing gene variants. Mast cells and leukotrienes appear to be important factors in atherosclerosis, in addition to their well-known role in allergy.