The impact of sinusitis on the long-term clinical outcomes of asthma

BACKGROUND Upper respiratory diseases have been linked with lower respiratory diseases. However, the long-term effect of sinusitis on the clinical outcomes of asthma has not been fully evaluated. OBJECTIVE The aim of this study was to investigate the impact of sinusitis on the disease progression of asthma. METHODS Seventy-five asthmatic patients confirmed with the methacholine bronchial provocation test or bronchodilator response were included. The study patients underwent paranasal sinus x-ray upon their asthma evaluation and they visited the hospital at least 3 years or longer. We retrospectively reviewed their medical records and compared data according to the presence of comorbid sinusitis. RESULTS Among the 75 asthmatic subjects, 38 subjects (50.7%) had radiologic evidence of sinusitis. Asthmatics with sinusitis had significantly lower forced expiratory volume in 1 second (FEV1; 79.2% vs. 88.2%) and PC20 values (5.2 mg/mL vs. 8.9 mg/mL) compared to asthmatics without sinusitis at the time of diagnosis. This difference in FEV1 disappeared (82.6% vs. 87.2%) in the 3-year follow-up, although FEV1 was more variable (31.7% vs. 23.5%) and worst FEV1 was also significantly lower in patients with sinusitis compared to those without (70.9% vs. 79.0%). There were no significant differences in the number of hospital visits, acute exacerbations, and scores for the asthma control test. CONCLUSION Although sinusitis was associated with lower baseline lung function and higher hyperreactivity, sinusitis was not related with significant deterioration in lung function over 3 years of follow-up. Asthmatics with sinusitis showed more variability in lung function during the follow-up period. Healthcare utilization was not different except antibiotics use.