Mortality risk in patients with chronic rhinosinusitis and its association to asthma

BACKGROUND Chronic rhinosinusitis (CRS) is a highly prevalent inflammatory condition, with significant effects on morbidity and quality of life. Given that other chronic inflammatory conditions have been associated with increased mortality risk, we sought to evaluate the relationship between mortality and CRS including the influence of asthma. Our objective was to determine if CRS, with or without asthma, is associated with altered risk of mortality. METHODS Using a statewide population database, we retrospectively identified 27,005 patients diagnosed with CRS between 1996 and 2012, and 134,440 unaffected controls matched 5:1 on birth year and sex. Risk of mortality was determined from Cox models and Kaplan-Meier curves were used to compare survival. RESULTS A significant interaction between CRS and asthma status was observed in which CRS appeared to confer a protective effect in asthma patients. Asthma, when present, increased mortality in CRS-negative controls (p-interaction < 0.0001). Independent of asthma status, CRS patients exhibited a decreased mortality risk (hazard ratio [HR] = 0.80; 95% confidence interval [CI], 0.74 to 0.85) compared to controls. However, in patients diagnosed at or before the median age of CRS onset (42 years) independent of asthma status, survival was not improved (HR = 0.98; 95% CI, 0.81 to 1.18). Risk of mortality was greater in CRS with nasal polyps (n = 1643) compared to 25,362 polyp-negative CRS patients (HR = 1.38; 95% CI, 1.09 to 1.77). CONCLUSION CRS was associated with lower risk of mortality compared to controls, and appeared to mitigate increased mortality from asthma. We posit that better survival conferred by CRS may be secondary to treatment. However, the etiology of this relationship and the effect of CRS treatment on mortality are unknown.