Statin Use and Amyotrophic Lateral Sclerosis Survival: A Population-Based Cohort Study

Abstract

Background

Dyslipidemia is common in amyotrophic lateral sclerosis (ALS). Statin use has been associated with both favorable and poor prognoses. We assessed whether statin use affects ALS survival.

Methods

We linked four Norwegian health surveys (1972–2003) with mandatory national registries to obtain information on premorbid health, ALS diagnosis, and death. Using the Norwegian Prescribed Drug Registry, we identified participants who had dispensed statins pre- and post-diagnosis. We first compared pre-diagnosis statin discontinuation rates between ALS patients and matched controls. Flexible parametric models were then fitted to estimate the relationship between statin use and survival time in ALS, using restricted mean survival time and hazard ratio (HR) as effect measures.

Results

A total of 524 patients (43% female) with ALS were included. Mean time from ALS diagnosis to death or end of study was 2.0 (SD 2.1) years. A substantial proportion of statin users (21%) discontinued statins during the year leading up to diagnosis. This group was characterized by poorer ALS prognosis compared to those adhering to statins and were included as statin users in our analysis. After adjusting for sex, age, birth year, riluzole use and premorbid smoking status, body mass index, and total cholesterol levels, statin use was not associated with ALS survival. The estimated mean survival difference comparing statin users to non-users was 0.74 (95% CI −5.98 to 7.47) months, corresponding to a HR of 0.97 (95% CI 0.77–1.23).

Conclusion

Statin use was not associated with ALS survival, suggesting that statins should not routinely be discontinued in ALS.