Use of Statin Medications Following Diagnosis in Relation to Survival among Women with Ovarian Cancer

Background: It has been suggested that the likelihood of survival among women with ovarian cancer could be increased by postdiagnosis statin use. This study examines the potential association between postdiagnosis statin use and cancer-specific mortality among women with ovarian cancer. Methods: This cohort study used SEER-Medicare data on women >= 66 years of age diagnosed with ovarian cancer during 2007 to 2012 who were enrolled in Medicare parts A, B, and D during the year after diagnosis. Statin use was defined as two or more fills for a statin during the year after diagnosis. Ovarian cancer-specific death was assessed starting 1 year after diagnosis. Marginal structural Cox models were used, adjusting for the inverse probability of treatment weighting and censoring weighting. Treatment weights and censoring weights were calculated using logistic regression models with a priori-defined covariates. Results: Among 2,195 women with ovarian cancer, 489 (22%) used statins within 1 year after their diagnosis. Over a mean follow-up of 2.2 years, 796 (36%) women died from ovarian cancer. The adjusted HR for ovarian cancer mortality comparing statin users to nonusers was 0.74 (95% confidence interval, 0.61-0.91). Conclusions: Findings from this and prior work suggest statin use following a diagnosis with ovarian cancer is associated with a lower risk of cancer death. Impact: Because, in most women, statin administration has limited side effects, a randomized trial of statins among patients with ovarian cancer may be warranted.