Association of severity of chronic rhinosinusitis with degree of comorbid asthma control.

BACKGROUND: Comorbid chronic rhinosinusitis (CRS) is associated with worse asthma control. However, no study has investigated whether CRS severity affects the degree of asthma control.

OBJECTIVE: To determine the effect size of an association between CRS severity and asthma control.

METHODS: A pilot study with a prospective cross-sectional design. Adult patients with CRS and asthma were recruited. CRS severity was measured using the 22-item Sinonasal Outcomes Test (SNOT-22), and asthma control was measured using the Asthma Control Test (ACT). Poor asthma control was defined as an ACT score of 19 or less. In addition to age and sex, we also assessed the participants' history of smoking, aeroallergen hypersensitivity, the presence of polyps, and current use of a corticosteroid-containing asthma inhaler. The association between SNOT-22 and ACT was assessed using univariate and multivariable linear regression.

RESULTS: A total of 40 patients were recruited. The mean (SD) SNOT-22 score was 43.6 (23.6), and the mean (SD) ACT score was 20.6 (4.8). We found that the SNOT-22 score was associated with the ACT score (adjusted β = -0.07; 95% confidence interval [CI], -0.13 to -0.02; P = .02) and with having poor asthma control (adjusted odds ratio, 1.06; 95% CI, 1.01-1.11; P = .02). A SNOT-22 cutoff score of 45 or higher had the greatest association with uncontrolled asthma (adjusted odds ratio, 14.96; 95% CI, 1.93-115.89; P = .01).

CONCLUSION: CRS severity is negatively associated with asthma control in patients with asthma and CRS. On the basis of this pilot study, further study is warranted to elucidate the effect of CRS severity on asthma control and to determine whether reduction in CRS severity translates to improvement in asthma control.