SAN DIEGO – Having asthma appears to significantly increase a patient’s risk for cardiovascular events, while having allergic rhinitis appears to lower a patient’s risk of some such events, results from a large cohort study demonstrated.
Studies of mouse models have suggested that Th1 inflammation "is associated with atherosclerosis and plaque development, while the Th2 or general allergic response seems to be protective against atherosclerosis," Dr. Angelina Crans Yoon said during a press briefing at the annual meeting of the American Academy of Allergy, Asthma, and Immunology. At the same time, results from human studies regarding the association between allergic rhinitis and cardiovascular events are mixed, said Dr. Crans Yoon, a first-year allergy fellow at Kaiser Permanente Los Angeles Medical Center.
In an effort to assess the relationship between cardiovascular disease and allergic rhinitis, she and her associates used the Kaiser Permanente Southern California regional database and ICD-9 codes to compare the incidence of cardiovascular and cerebrovascular events and all-cause mortality in a cohort of 109,229 allergic rhinitis patients and 92,775 asthma patients who were seen between Jan. 1, 1995, and Dec. 31, 2012. The cohorts were matched by age, sex, and ethnicity to reference cohorts and followed for a median of 8 years.
Patients with allergic rhinitis had a significantly lower risk of myocardial infarction (hazard ratio, 0.75), cerebrovascular disease (HR, 0.81), and all-cause mortality (HR, 0.51), yet their risk of all cardiovascular events was equal to that of the control cohort (HR, 0.97). At the same time, patients with asthma had a significantly higher risk of all cardiovascular disease (HR, 1.36), yet no significantly higher risk of cerebrovascular disease (HR, 1.03) or all-cause mortality (HR, 1.00).
The findings "led us to think of more questions," Dr. Crans Yoon said. "Why is there this decreased risk of events in patients with allergic rhinitis? What explains the risk of cardiovascular events in patients with asthma? Is atopy related to these differences? We started some secondary analyses looking at medication use. It looks like if you use any medications for allergic rhinitis or asthma, you have a decreased risk of some of these events, except for long-acting beta-agonists, which is consistent with previous reports."We’re also starting to look at specific IgE data on these patients. It also looks like positive IgE testing may be associated with a decreased risk of these events., she said".
She speculated that asthma physiology may explain why patients with asthma had significantly higher risk of cardiovascular disease but not cerebrovascular disease. "The interesting point is that, potentially, atopic asthmatics may not have the same increased risk," she said.
Dr. Crans Yoon reported she had no relevant financial conflicts.
Dr. Jun Chiong, FCCP, comments: Clinicians have yet to sort out a clear connection between asthma and heart disease, but the link is a statistical fact. In some studies, the link persist even after adjusting the smoking history and other risk factors. A variety of theories about the possible link such as genetics and inflammation has come up, as that's also what makes the arteries harden.
A more defined and directed study is necessary in order to better don’t understand exactly what the connection is. People who are having heart failure, angina, or heart pain such as tightness in the chest may mistake those symptoms for breathing difficulty and other asthma symptoms. Heart failure can cause fluid to build up in the lungs and airways, and can lead to symptoms that resemble asthma symptoms such as wheezing, coughing, and shortness of breath.