Monday, July 28, 2014
Why Does Weight Affect Asthma?
I have asthma and am overweight. I know I need to lose weight (believe me, I`m trying) but what I don`t understand is what my weight has to do with an asthma attack. I have had asthma since I was a kid and I wasn`t overweight then.
How can BMI affect your lungs? I always thought asthma was related to inflammation, allergies, cold air, viruses, air pollution, dust mites, etc., not how much I weigh.
We are not 100% certain. Recent studies have shown asthmatics who are also overweight have more asthma symptoms, more frequent asthma attacks, require more asthma medicine (on average), and are more likely to visit the emergency department with asthma or be admitted.
There are mechanical (functional) changes in the lungs that are associated with obesity. For example, as weight increases so does shortness of breath and wheezing, even in those without asthma. Additionally, there are changes on breathing tests. Increased weight is associated with reduced lung volumes and reduced amounts of air that can be blown out in 1 second. Abdominal obesity (weight in your belly or apple shaped) is worse than in your hips (pear shaped). Abdominal obesity is associated with worsening lung function and limits the ability of the diaphragm (biggest breathing muscle separating the chest from the abdomen) to move properly for breathing.
Some researchers believe there may be an issue with inflammation in the body or how obese people respond to anti-inflammatory medicines but more research is needed in this area.
Continue to work on reducing weight. It is a difficult balance because more asthma flare-ups usually mean more oral steroids which can cause water retention and weight gain. Hopefully, by working closely with your provider you can keep your asthma controlled to allow exercise which will help with your weight loss goals.
Cathy Benninger, RN, MS, APRN, C-AE
Clinical Assistant Professor
Director, OSU Asthma Center Educational Program
College of Medicine
The Ohio State University