Causes of death for intensive care survivors with and without acute kidney injury in 5-year follow-up.

Background: Data on the causes of death and long-term mortality of intensive care unit-treated hospital survivors with acute kidney injury (AKI) are limited. The goal of this study was to analyze the causes of death among critically ill patients during a 5-year follow-up.

Methods: In this predetermined sub-study of a prospective, observational, multi-center cohort from the FINNAKI study, we analyzed 2436 patients who were discharged from the hospital. Statistics Finland provided the follow-up data and causes of death.

Results: During the follow-up, 765 (31%) patients died, of whom 295 (39%) had AKI and 73 (9.5%) had received renal replacement therapy. More than half of the deaths in both the non-AKI and AKI groups occurred after the 1 year follow-up (58% vs. 54%, respectively). The three most common causes of death in AKI were cardiovascular diseases (36%), malignancies (21%), and neurological diseases (11%). In early deaths (<90 days) cardiovascular causes were more prevalent in AKI patients compared to non-AKI (38% vs 25%, P = .037.) In six cases (0.8%), the main cause of death was kidney disease, out of which five were in the AKI group. In patients with cardiovascular causes, the median time to death was shorter in AKI patients compared to non-AKI patients (508 vs 816 days, P = .018).

Conclusion: Cardiovascular causes and malignancies account for more than half of the causes of death in patients who had suffered AKI, while death from kidney disease after AKI is rare. Early cardiovascular deaths are more prevalent in AKI compared to non-AKI patients.