Association between Preexisting Sleep Disorders and Oncologic Outcome in Patients with Oral Cavity Squamous Cell Carcinoma: A Nationwide Propensity Score—Matched Population-Based Cohort Study

SIMPLE SUMMARY: We aimed to estimate the effects of preexisting sleep disorders on the oncologic outcomes of patients with oral squamous cell carcinoma (OSCC) after receiving standard treatments. We conducted a head-to-head propensity-score-matching-based study to mimic a randomized trial to compare the survival, locoregional recurrence, and distant metastasis rates between OSCC patients with and without sleep disorders. The patients with sleep disorders receiving curative treatments for OSCC had poorer oncologic outcomes than did those without sleep disorders. Preexisting sleep disorders may be survival predictors in patients with OSCC. Studies on how pharmacological and behavioral treatments for sleep problems improve survival benefits in patients with OSCC are warranted. ABSTRACT: Purpose: To investigate the effects of preexisting sleep disorders on the oncologic outcomes of patients receiving standard treatments for oral squamous cell carcinoma (OSCC). Methods: The patients recruited from the Taiwan Cancer Registry Database who had received surgery for stage I–IVB OSCC. The Cox proportional hazards model was used to analyze all-cause mortality, locoregional recurrence (LRR), and distant metastasis (DM). The patients were categorized into those with and without sleep disorders (Groups 1 and 2, respectively) through propensity score matching. Results: In the multivariate Cox regression analysis, the adjusted hazard ratios for all-cause mortality, LRR, and DM for Group 1 compared with Group 2 were 1.19 (95% confidence interval (CI): 1.04–1.36; p = 0.011), 1.47 (95% CI: 1.23–1.75; p < 0.001), and 1.15 (95% CI: 1.02–1.44; p = 0.025), respectively. Conclusion: OSCC patients with sleep disorders demonstrated poorer oncologic outcomes than did those without sleep disorders. Therefore, before OSCC surgery, patients with OSCC should be screened for preexisting sleep disorders because they may serve as predictors for survival in these patients. Future studies investigating the survival benefits of pharmacological and behavioral treatments for sleep problems in patients with OSCC are warranted.