Statin use and reduced all-cause mortality in critically ill patients with asthma: a retrospective cohort study based on the MIMIC-IV database

Background Previous research suggests potential therapeutic benefits of statin administration in intensive care unit (ICU) patients. However, its clinical role in critically ill patients with asthma remains undetermined. We sought to investigate the association between statin use and all-cause mortality rate in this population. Methods This retrospective study utilized data from the Medical Information Mart for Intensive Care IV(MIMIC-IV) database. Participants were critically ill patients with asthma, categorized into two groups based on statin administration during their ICU stay. We evaluated the association between statin use and mortality at multiple time points using multivariable Cox proportional hazards models and Kaplan-Meier survival analysis. We also performed subgroup analyses and propensity score matching (PSM) to strengthen the robustness of our findings. Results We included 4,091 asthma patients (mean age 59.2 ± 17.5 years, 27.4% on statins during ICU). In adjusted Cox models, statin use was associated with lower risks of 30-day (HR = 0.62, 95% CI: 0.45–0.85, P = 0.003), 90-day (HR = 0.67, 95% CI: 0.53–0.86, P = 0.001), and 1-year mortality (HR = 0.74, 95% CI: 0.61–0.90, P = 0.003). PSM and subgroup analyses yielded consistent results. Initiation of statin therapy during the ICU stay was associated with lower mortality irrespective of pre-ICU use. Continuous statin use (both before and during ICU) showed a more pronounced association with lower 30-day mortality risk (HR = 0.31, 95% CI: 0.15–0.65, P = 0.002). Conclusions Statin use was associated with lower short-term and long-term all-cause mortality in critically ill patients with asthma, with a more pronounced association observed for continuous statin therapy. However, given the retrospective design and lack of data on the primary reasons for ICU admission, these findings should be interpreted as associations rather than causal effects. Further prospective studies are warranted to validate these observations and to clarify the role of statins in critical care settings.