There are many well-defined risk factors for fatal asthma exacerbation; however, few data exist about the link between the severity of asthma and severity of exacerbation. The aim of this study was to determine if there is any patient and disease-related factor that predicts the severity of asthma exacerbation. The retrospective data of asthmatic patients followed up in our clinic were analyzed. Asthmatic patients who had at least one exacerbation were included. Patient and disease characteristics, comorbidities, and compliance were evaluated. We analyzed 335 asthma exacerbations of 189 asthmatic patients. Eighteen patients had intermittent asthma, 115 patients had mild persistent asthma, 45 patients had moderate persistent asthma, and 11 patients had severe persistent asthma. Of the 189 asthmatic patients 8.1% of the exacerbations were mild, 52.5% were moderate, and 39.4% were severe. There was a significant correlation between the severity of asthma and severity of exacerbation (r = 0.32; p < 0.001). When elderly (> or =60 years old) and younger (<60 years old) asthmatic patients were compared, elderly asthmatic patients had severe asthma exacerbation significantly at a higher rate than younger asthmatic patients (severe asthma exacerbation rates are 67.3 and 33.9% in elderly patients and younger asthmatic patients, respectively; p < 0.001). A significant correlation was found between the severity of exacerbation and age (r = 0.25; p < 0.001). Among the other patient and disease-related factors, asthma severity and older age were the only significant factors that contributed to the severity of exacerbation. These data show that older age as a patient-related factor and worse asthma severity as a disease-related factor could contribute to exacerbation severity in asthmatic patients.