Background: This study aimed to examine the association between preadmission statin use and 90-day mortality in critically ill patients and to investigate whether this association differed according to statin type and dose. We hypothesized that preadmission statin use was associated with lower 90-day mortality.
Methods: This retrospective cohort study analyzed the medical records of all adult patients admitted to the intensive care unit in a single tertiary academic hospital between January 2012 and December 2017. Data including preadmission statin use, statin subtype, and daily dosage were collected, and the associations between these variables and 90-day mortality after intensive care unit admission were examined. The primary endpoint was 90-day mortality.
Results: A total of 24,928 patients (7,396 statin users and 17,532 non-statin users) were included. After propensity score matching, 5,354 statin users and 7,758 non-statin users were finally included. The 90-day mortality rate was significantly higher in non-statin users (918 of 7,758; 11.8%) than in statin users (455 of 5,354; 8.5%; P < 0.001). In Cox regression analysis, the 90-day mortality rate was lower among statin users than among non-statin users (hazard ratio: 0.70, 95% CI: 0.63 to 0.79; P < 0.001). Rosuvastatin use was associated with 42% lower 90-day mortality (hazard ratio: 0.58, 95% CI: 0.47 to 0.72; P < 0.001). There were no specific significant differences in the association between daily statin dose and 90-day mortality. In competing risk analysis, the risk of noncardiovascular 90-day mortality in statin users was 32% lower than that in non-statin users (hazard ratio: 0.68, 95% CI: 0.60 to 0.78; P < 0.001). Meanwhile, cardiovascular 90-day mortality was not significantly associated with statin use.
Conclusions: Preadmission statin use was associated with a lower 90-day mortality. This association was more evident in the rosuvastatin group and with noncardiovascular 90-day mortality; no differences were seen according to daily dosage intensity.