Analyze health care needs and outcomes-defined by changes in health care utilization-in cohorts of patients with respiratory comorbidities and requiring sinus surgery for the treatment of chronic rhinosinusitis (CRS). Retrospective database analysis. US-wide claims database (MarketScan). All patients with endoscopic sinus surgery (CPT 31254-31288) in 2008 and at least 2 years of continuous enrollment prior and post surgery were analyzed for concurrent comorbidities (asthma, polyps, aspirin sensitivity, and allergies). Inpatient and outpatient events as well as prescriptions related to the treatment of CRS were analyzed for frequency and cost, based on respiratory comorbidities. A total of 9105 patients were included and subdivided as following: no respiratory comorbidity (N = 4780), asthma only (N = 1167), polyps and asthma (N = 721), Samter's triad (N = 91), and additional subgroups based on various combinations of concurrent comorbidities. Before surgery, costs were flat, ranging from $296.4 (95% CI, $263.1-$329.8) per patient per year for patients in the no comorbidity group to $2189 (95% CI, $1449.2-$2930.1) for patients with Samter's triad. Surgery was preceded by at least 6 months of increased health care utilization (outpatient care and prescriptions). Following surgery, health care needs declined rapidly and reached baseline levels within 3 to 4 postoperative months. Patients with asthma received significantly more health care for CRS than patients without asthma through the entire study. Patients with CRS incur continuous costs and health care needs, due to the chronic nature of their disease. All patients, regardless of comorbidity, experienced significant decline in health care needs following sinus surgery from their preoperative state.