Runny Nose May Increase Your Risk Of Developing Asthma
In this entry, I would like to discuss some recent findings on the association with "rhinitis" - inflammation of the nasal passages that often causes runny nose and congestion -- and asthma. In an earlier entry, I reviewed the connection between allergies and asthma. Over 2/3 of asthmatics have allergies, which often cause symptoms in the form of hay fever. This number is even higher in kids, and many children with asthma are followed by a pediatric allergist since many of them developed allergies requiring treatment before developing asthma. But what about the other 1/3 of adults who do not have allergies, and is there a connection between having chronic nasal symptoms and asthma regardless of allergies?
Rhinitis is associated with developing asthma
Many individuals have asthma and allergies, and have symptoms of both asthma and hay fever. In general, there are more people with hay fever who do not have asthma than those who do. Is there a risk of developing asthma in adulthood if you have rhinitis, whether it is allergic or not? A recent study in a prominent international medical journal studied this question directly.
In order to answer such questions with confidence, research studies with large numbers of patients are necessary to be sure that any differences found along the way are not due to chance alone. The study recruited over 6,000 individuals who did not have asthma to be followed over about 9 years to look for the development of asthma. Some of these individuals had allergies with rhinitis, some had allergies without symptoms, and some had rhinitis but tested negative for allergies. A "control" group of healthy individuals -- no allergies or rhinitis symptoms -- was recruited in tandem. When these four groups were followed over time, 4% with allergies and rhinitis developed asthma, while only 1.1% of healthy individuals did.
The statistical analysis showed with a very high degree of confidence that the difference between these groups was not due to chance. Interestingly, nearly as many (3.1%) of individuals who had rhinitis without allergies developed asthma as those who had allergies and rhinitis. This suggests that the presence of rhinitis, with or without associated allergies, is a risk factor for developing asthma. The authors concluded that there is an association between inflammation of the nose and developing asthma.
While the connection between asthma and allergies is well known, it is clear that many peoples' asthma is not related to or caused by allergies. The recent study complements these findings by showing that asthma develops more commonly in individuals with rhinitis that is not related to allergies than individuals who have allergies but without rhinitis. This suggests that there is a connection between the nose and lungs that is related to inflammation in these tissues.
To be clear, not everyone (in fact only a small minority, according to the study) of adults who have rhinitis will develop asthma in adulthood. However, it is important to be aware that rhinitis and asthma are related conditions, and that you should speak with your doctor if you have rhinitis and unexplained shortness of breath or cough, as asthma could explain these symptoms.