Obesity-asthma phenotype: Effect of weight gain on asthma control in adults

The obesity-asthma phenotype has become an increasingly common situation in our clinical practice. The mechanisms behind poor asthma control in subjects who are obese remain unclear. We aimed to determine the effect of obesity on asthma control in a group of adult patients Method: Subjects who had been diagnosed as having asthma and who were admitted to our clinic were included to this study. Body mass index (BMI) and asthma control status of the patients were evaluated. BMI values at the time of diagnosis were also collected from the patient files, and the difference between basal and current BMI values were calculated. The effect of obesity and weight gain on asthma control was investigated.

The study population was composed of 218 patients (29 men, 189 women), with a mean (standard deviation) age of 52.01 ± 11.6 years. Fifty-four percent of the patients were obese, 27.5% were overweight, and 18.3% were of normal weight. The baseline and current BMI values were higher in women than in the men. BMI increased with the increase in age or disease duration. Asthma control was poor in the patients who were obese and overweight despite optimal treatment. Moreover, asthma control was worse in patients who gained weight during the follow-up period.

In our study, we found a significant relationship between obesity and asthma control. In addition, weight gain and being nonatopic also was found to worsen asthma control. In light of our finding that weight gain led to a decrease in asthma control, we suggest that weight loss may improve the course of asthma.