Cardiovascular medications and survival in people with ovarian cancer: A population-based cohort study from British Columbia, Canada.

OBJECTIVES: Research examining survival among people with ovarian cancer following use of statins or ß-blockers has been conflicting. Many studies to date have suffered from immortal time bias and/or had limited power. To address these limitations, we used time-dependent analyses to study the association between statin or ß-blocker use among all people diagnosed with an epithelial ovarian cancer in British Columbia, Canada between 1997 and 2015. METHODS: Population-based administrative data were linked for 4207 people with ovarian cancer. Statin or ß-blocker use was examined using time-dependent variables for any use, cumulative duration of use and by user-group according to whether use was initiated before or after their ovarian cancer diagnosis. Cox proportional hazards models were run to estimate the association between statin or ß-blocker use and survival. RESULTS: Any postdiagnosis use of statins was associated with better ovarian cancer survival in the full cohort (adjusted hazard ratio (aHR) = 0.76, 95% CI 0.64, 0.89) and among women with serous cancers (aHR = 0.80, 95%CI 0.67-0.96). This was primarily driven by new use post-diagnosis (aHR = 0.67, 95%CI, 0.51-0.89), but there was a trend towards better survival among those who continued use from before diagnosis (aHR 0.83, 95%CI, 0.68-1.00). There was no statistically significant association between ß-blocker use and survival. CONCLUSION: Postdiagnosis statin use was associated with improved survival among people with ovarian cancer. Given the consistency of this finding in the literature, we recommend a randomized clinical trial of statin use in people with ovarian cancer.

Metformin use and survival in people with ovarian cancer: A population-based cohort study from British Columbia, Canada.

OBJECTIVES: There is an active debate regarding whether metformin use improves survival in people with ovarian cancer. We examined this issue using methods designed to avoid immortal time bias-as bias that occurs when participants in a study cannot experience the outcome for a certain portion of the study time. METHODS: We used time-dependent analyses to study the association between metformin use for all 4,951 patients diagnosed with ovarian cancer in 1997 through 2018 in the province of British Columbia, Canada. Cox proportional hazards models were run to estimate the association between metformin and survival in the full cohort of ovarian cancer patients and among a cohort restricted to patients with diabetes. RESULTS: Metformin use was associated with a 17 % better ovarian cancer survival in the full cohort (adjusted hazard ratio (aHR) = 0.83 (95 %CI 0.67, 1.02)), and a 16 % better ovarian cancer survival for serous cancers patient's cohort (aHR = 0.84 (95 %CI 0.66, 1.07)), although both were not significant. However, a statistically significant protective effect was observed when restricting to the diabetic cohort (aHR = 0.71 (95 %CI 0.54-0.91)), which was also seen among serous cancers (aHR = 0.73 (95 %CI 0.54-0.98)). CONCLUSION: Metformin use was associated with improved ovarian cancer survival. The lack of statistical significance in the full cohort may reflect that diabetes is associated with reduced cancer survival, and thus diabetes itself may offset the benefit of metformin when examining the full cohort. Future research should examine metformin use among non-diabetic ovarian cancer patients.

High Prediagnosis Inflammation-Related Risk Score Associated with Decreased Ovarian Cancer Survival.

BACKGROUND: There is suggestive evidence that inflammation is related to ovarian cancer survival. However, more research is needed to identify inflammation-related factors that are associated with ovarian cancer survival and to determine their combined effects. METHODS: This analysis used pooled data on 8,147 women with invasive epithelial ovarian cancer from the Ovarian Cancer Association Consortium. The prediagnosis inflammation-related exposures of interest included alcohol use; aspirin use; other nonsteroidal anti-inflammatory drug use; body mass index; environmental tobacco smoke exposure; history of pelvic inflammatory disease, polycystic ovarian syndrome, and endometriosis; menopausal hormone therapy use; physical inactivity; smoking status; and talc use. Using Cox proportional hazards models, the relationship between each exposure and survival was assessed in 50% of the data. A weighted inflammation-related risk score (IRRS) was developed, and its association with survival was assessed using Cox proportional hazards models in the remaining 50% of the data. RESULTS: There was a statistically significant trend of increasing risk of death per quartile of the IRRS [HR = 1.09; 95% confidence interval (CI), 1.03-1.14]. Women in the upper quartile of the IRRS had a 31% higher death rate compared with the lowest quartile (95% CI, 1.11-1.54). CONCLUSIONS: A higher prediagnosis IRRS was associated with an increased mortality risk after an ovarian cancer diagnosis. Further investigation is warranted to evaluate whether postdiagnosis exposures are also associated with survival. IMPACT: Given that pre- and postdiagnosis exposures are often correlated and many are modifiable, our study results can ultimately motivate the development of behavioral recommendations to enhance survival among patients with ovarian cancer.