Beta-blockers and epithelial ovarian cancer survival: A Norwegian population-based cohort study.

Cancer diagnosis and therapy cause stress to the body. Preclinical studies have shown that stress hormones can stimulate tumor progression and metastasis by interacting with β-adrenergic receptors, and that β-blockers can inhibit those processes. We assessed if β-blocker use was associated with survival in a nationwide cohort of women with epithelial ovarian cancer (EOC). We identified all women aged ≥40 years who underwent EOC surgery in 2004-2018 in Norway through the Cancer Registry of Norway. We estimated the association between peri-diagnostic and post-diagnostic β-blocker use and survival. We used Cox models, adjusted for sociodemographic and health factors, and reported hazard ratios (HRs) and 95% confidence intervals (CIs). The difference in overall survival time between β-blocker users and non-users was estimated as the difference in restricted mean survival time at 5 years after diagnosis using flexible parametric models. We included 3911 women with EOC; 540 (14%) used β-blockers at diagnosis, 1672 (43%) died of the disease, and 1882 (48%) died overall. We found an association between peri-diagnostic β-blocker use and longer EOC-specific survival (HR = 0.85, 95%CI 0.73-1.00; p-value = 0.048), and an indication of an association with overall survival (HR = 0.89, 95%CI 0.77-1.02; p-value = 0.101). Analysis of post-diagnostic β-blocker use, which included only women who survived 12 months or longer (n = 3344), found similar associations. At 5 years from diagnosis, peri-diagnostic β-blocker users lived on average 1.28 months longer than non-users (95%CI 0.01-2.60 months). The results support the hypothesis that β-blocker use improves EOC-specific survival in women with EOC.