Introduction:
Asthma and obesity are among diseases that cause several problems and impair quality of life.  The concurrence of these diseases, changes in the respiratory physiology, changes associated with obesity and limited activity associated with asthma may cause an interaction between the two conditions.
Materials and Methods:
We studied the epidemiologic characteristics of all recently diagnosed cases of asthma with no previous treatment who visited the Respiratory Diseases Clinic of the Ghaem Hospital from 2004 to 2007, their Body Mass Indexes (BMI) were calculated and then spirometry was performed in all cases.
Results:
We studied 232 cases with the mean age of 38.96±12.94 years and the mean BMI of 27.05±4.92. Cough and exertional dyspnea were the most common clinical symptoms. In spirometric evaluations, the mean maximum mid-expiratory flow (MMEF) increased with weight, which was not, however, insignificant. FVC in obese patients was significantly less than in normal weight cases. A significant correlation was not also seen between BMI and FEV1 (r=-0.023, P=0.729).
Conclusion:
Except for FVC which had a significant correlation with BMI, other studied indices yielded no significant results, which calls for more extensive studies with larger populations. Considering the fact that mild asthma is less common in obese patients, better weight control in asthmatic patients can promote their quality of life and make asthma management more effective.