Five-year relative survival in sleep apnea patients with a subsequent cancer diagnosis.

In vitro and animal studies suggest that intermittent hypoxia characterizing sleep apnea contributes to accelerated cancer progression. However, the impact of sleep apnea on survival subsequent to cancer diagnosis is unknown.We identified a cohort of 1,575 adults diagnosed with sleep apnea between 2005-2014 with a subsequent cancer diagnosis via linkage of University of Washington Medicine system and a population-based cancer registry serving the same Seattle-Puget Sound region. We computed age-standardized 5-year relative survival after cancer diagnosis for all cancers combined, and for specific cancer sites, for both the sleep apnea cohort (SAC) and the general Seattle-Puget Sound population and used US life tables as the reference population. Relative survival was estimated by sex, cancer stage and healthcare engagement.Five-year overall relative survival for cancer was more favorable in the SAC than in the general population (83.6%; 95% CI: 79.8-86.8% vs 71.6%; 95% CI: 71.3-71.9%); this pattern was applicable to most specific cancer sites. However, 5-year relative survival was slightly less favorable in the SAC among patients with melanoma (97.7%; 95% CI: 84.6-99.7% vs 99.2%; 95% CI: 98.8-99.5%) and cancer of the corpus uteri (84.0%; 95% CI: 58.2-94.5% vs 84.6%; 95% CI: 83.1-86.0%).The fact that survival after cancer, overall and for most cancer sites, was more favorable in sleep apnea patients warrants larger community-based studies to further tease out effects of sleep apnea and treatment on site-specific survival for different cancer types, particularly in patients with melanoma or uterine cancer.