Trends in statin use and its association with mortality among older U.S. cancer survivors with and without coronary heart disease.

Aims

Investigate the distribution of statin and its association with cause-specific mortality among older (aged 65 years or older) U.S. cancer survivors, stratified by coronary heart disease (CHD) status.

Methods

A retrospective cohort study utilized data from ten NHANES cycles (1999-2000 through 2017-2018) and mortality follow-up began from the date of survey participation and continued through December 31, 2019. Statin exposure was identified via a 30-day recall period at the time of the household interview. Mortality hazard ratio (HR) were estimated using Cox proportional hazards regression, and survival rates were assessed via Kaplan-Meier curves. Subgroup analyses were performed to explore potential effect modifiers including sex, smoking, alcohol consumption, diabetes, and hypertension.

Results

Among 2714 cancer survivors, the average age was 75.47, 1473 (54.27%) were men and 649 (23.91%) had CHD. The observed proportion of statin users tripled from 20.0% (1999-2000 cycle) to 56.0% (2015-2016 cycle) with distinct trends by CHD status and sex. Over a mean follow-up of 81 months, statin users with CHD exhibited significantly lower all-cause, cardiac, and cancer-related mortality proportions compared to non-users (52.0%vs.72.8%, 18.3% vs.25.9%, 11.5% vs. 18.0%, respectively, P < 0.05 for all). Statin use was associated with higher survival outcomes across all mortality categories, as demonstrated by Kaplan-Meier analysis (all log-rank p < 0.05). Model 2 (fully adjusted for sex, race, education level, marital status, PIR, alcohol consumption, smoking status, DM, and hypertension) showed that statin use in CHD patients was independently associated with lower all-cause (HR: 0.797, 95% CI: 0.705-0.901), cardiac (HR: 0.765, 95% CI: 0.594-0.984), and cancer-related mortality (HR: 0.774, 95% CI: 0.615-0.973), while, in the non-CHD group, statin use was associated with lower all-cause mortality (HR: 0.782, 95% CI: 0.673-0.909) but not with cardiac or cancer-related mortality. Significant interactions were observed in subgroup analysis for alcohol consumption and hypertension with all-cause mortality (all P < 0.05), with consistent benefits among CHD patients.

Conclusion

Statin use was associated with lower all-cause, cardiac, and cancer-related mortality in older cancer survivors with CHD, but not with cancer-related mortality in those without CHD. These findings are hypothesis-generating and require prospective validation.