Statin exposure after multiple myeloma diagnosis and risk of all-cause mortality, venous thromboembolism, pathological fractures, and acute kidney injury: a propensity score-matched retrospective cohort study.

BACKGROUND: Multiple myeloma (MM) carries substantial risks of venous thromboembolism (VTE), pathological fractures, acute kidney injury (AKI), and death. Statins possess anti-inflammatory, immunomodulatory, and anti-thrombotic properties that may reduce these complications, yet their associations with several key MM outcomes have not been evaluated simultaneously in a single real-world cohort. OBJECTIVES: To evaluate the association between post-diagnosis statin exposure and 5-year all-cause mortality, VTE, pathological fractures, and AKI in MM. METHODS: We conducted a retrospective cohort study in the TriNetX Linked network (query date: 16 January 2026). Adults with MM were classified by statin exposure on or after diagnosis. We applied 1:1 propensity score matching on 59 baseline covariates. Outcomes were assessed from day 1 through 5 years using Kaplan-Meier methods and Cox proportional hazards models. To assess robustness to unmeasured confounding, E-values were calculated for effect estimates and their confidence interval (CI) limits. RESULTS: Among 43 543 adults with MM, 8756 had post-diagnosis statin exposure. After matching, 7167 patients remained in each cohort with strong covariate balance. Statin exposure was associated with lower 5-year mortality [17.5% vs. 26.0%; hazard ratio (HR) = 0.591, 95% CI: 0.549-0.635], VTE (9.2% vs. 12.0%; HR = 0.688, 95% CI: 0.617-0.767), and pathological fractures (4.6% vs. 7.6%; HR = 0.541, 95% CI: 0.469-0.623). AKI risk was similar in absolute terms (19.3% vs. 19.7%; P = 0.606), although time-to-event analysis identified a modest hazard reduction (HR = 0.900, 95% CI: 0.825-0.981). Findings were robust to unmeasured confounding based on E-values. CONCLUSIONS: In this propensity score-matched electronic health record cohort study, statin exposure after MM diagnosis was associated with improved 5-year survival and fewer VTEs and pathological fractures, with a modest time-to-event benefit for AKI. Prospective studies should evaluate statin initiation as an adjunct strategy in MM management.