Purpose: In ovarian cancer patients and mouse models, psychosocial stress is associated with higher circulating markers of angiogenesis and cell migration, impaired immune response, and increasing tumor burden and aggressiveness. In the Nurses' Health Studies (NHS/NHSII), we assessed whether phobic anxiety, a marker of chronic distress, was associated with risk of incident ovarian cancer as well as survival among ovarian cancer patients.
Methods: We used Cox proportional hazards regression to model the relative risks (RRs) and 95 % confidence intervals (CI) of ovarian cancer incidence and survival by categories of the Crown-Crisp phobic anxiety index (CCI).
Results: We identified 779 cases of ovarian cancer during 2,497,892 person-years of follow-up. For baseline CCI (NHS: 1988; NHSII: 1993), we observed a statistically nonsignificant increased risk of epithelial ovarian cancer (RR for CCI ≥ 4 vs. 0 or 1: 1.14; 95 % CI 0.96-1.36). However, when we updated CCI (NHS: 2004; NHSII: 2005), the associations were attenuated. Pre-diagnosis CCI was not associated with ovarian cancer survival (RR for ≥4 vs. 0 or 1: 1.00; 95 % CI 0.77-1.31); results were similar for post-diagnosis CCI.
Conclusions: Distress, as measured by phobic anxiety symptoms, was not associated with ovarian cancer risk, although we cannot rule out a modest association. Future research should explore the role of phobic anxiety and other forms of psychological distress and ovarian cancer risk and survival.
Keywords: Anxiety; Cancer; Distress; Oncology; Ovarian cancer.