Use of statins results in reduced all-cause mortality in nearly 30,000 veterans with colorectal cancer (CRC), results of a study have shown.
“The effect of statin drugs outcomes of patients diagnosed with CRC is uncertain because of inconsistency in the published literature,” according to the researchers, led by Thomas F. Imperiale from Indiana University School of Medicine, Richard L Doudebush VA Medical Center, and Regenstrief Institite, Inc. in the US, who also presented the study at the Digestive Disease Week (DDW) 2022.
Imperiale and his colleagues examined the association between statin use and all-cause mortality from a large database on CRC, which was created to investigate the incidence, prognosis, and risk factors for postcolonoscopy CRCs. The parent retrospective cohort study used VA-Medicare administrative data and involved veterans aged 50‒85 years with newly diagnosed CRC between 1 January 2013 and 31 December 2013 who were followed until death or who were censored on 30 April 2020.
Cox proportional hazards were used to assess both univariate and multivariate effects of statin use on time to all-cause mortality, adjusted for demographics, comorbidity, family history of CRC, aspirin, and nonsteroidal anti-inflammatory drug (NSAID) use, and CRC stage. Statin use was defined as ≥30 days of use in each of the 2 years prior to CRC diagnosis. The researchers also performed a secondary analysis using multiple logistic regression with 5-year all-cause mortality as the outcome.
Of the 29,866 veterans with CRC (mean age 67.4 years, 98 percent male, 80 percent White) included in this study, 10,780 (35 percent) were using statins. A total of 20,654 (69 percent) patients died at the time of censoring, and 15,915 (53 percent) were alive 5 years after CRC diagnosis. [DDW 2022, abstract Tu1421]
Veterans on statins were usually older, had more comorbidities, more frequent aspirin and NSAID use, a lower number of current smokers, a higher percentage of stage I CRCs, and a lower proportion of stage IV CRCs.
Statin users had an adjusted hazard ratio [HR] of 0.93 (95 percent confidence interval [CI], 0.89‒0.95), which was consistent with the 7-percent reduction found in the risk of all-cause mortality. Multivariate analysis revealed an adjusted odds ratio of 0.82 (95 percent CI, 0.77‒0.87) for statin use, consistent with an 18-percent decrease in the likelihood of 5-year all-cause mortality.
“Subsequent studies are needed that consider postdiagnosis treatment modalities, statin dose and duration, and cause-specific mortality. Statins may be a useful adjunct in the treatment of CRC,” the researchers said.
In a recent meta-analysis by Jing Yang and colleagues, statin use was associated with a moderate reduction in cancer-specific mortality (HR, 0.78, 95 percent CI, 0.74‒0.84). Statin use also correlated with improved recurrence-free survival (HR, 0.87, 95 percent CI, 0.78‒0.97), but not with improvement in progression-free survival (HR, 1.05, 95 percent CI, 0.95‒1.16). [Medicine (Baltimore) 2020;99:e19596]
“Many of the treatments that are beneficial for nonrandom cohort analysis have shown no benefit when tested in randomized clinical trials,” the authors said. “More clinical studies, especially randomized controlled trials, are warranted to confirm these associations.”