Patient-reported sleep outcomes lack association with mucosal eosinophilia or neutrophilia in patients with chronic rhinosinusitis undergoing functional endoscopic sinus surgery

Background: Chronic rhinosinusitis (CRS) is associated with sleep dysfunction, but the underlying pathophysiology is poorly understood. The purpose of this study was to determine if mucosal eosinophilia or neutrophilia were associated with sleep dysfunction severity or altered the improvement in sleep dysfunction following functional endoscopic sinus surgery (FESS).

Methods: A total of 104 patients with medically refractory CRS with nasal polyposis (CRSwNP) and CRS without nasal polyposis (CRSsNP), completed the Pittsburgh Sleep Quality Index (PSQI) before and after FESS. Anterior ethmoid mucosa was collected during FESS and densest infiltrates of eosinophilia and neutrophilia per high-power field (HPF) were determined by microscopy. Eosinophilic (>10 eosinophils/HPF) and neutrophilic (>4 neutrophils/HPF) CRS were then compared to preoperative and postoperative PSQI measures.

Results: Of 104 study participants, 88 (85%) reported preoperative PSQI scores consistent with "poor sleep," (PSQI total > 5). The cohort overall demonstrated significant improvement in poor sleep (65%; χ² = 12.03; p < 0.001) 16.8 ± 5.0 months after FESS. Regardless of nasal polyposis, neither eosinophilic nor neutrophilic CRS was associated with differences in mean postoperative PSQI improvement. However, in patients with neutrophilic CRSsNP, there was a significant relationship between severity of neutrophilia and improvement in sleep latency (R = -0.798, p = 0.003) and sleep efficacy (R = -0.777, p = 0.005).

Conclusion: Chronic inflammation has been hypothesized to play a pathophysiologic role in sleep dysfunction associated with CRS. This study suggests that in patients with medically refractory CRS, evidence of mucosal eosinophilia and neutrophilia lack strong associations with patient-reported sleep dysfunction or improvements in sleep quality after FESS, overall. However, neutrophilia may impact sleep latency and efficacy in patients with CRSsNP.