Prospective study of risk factors for community-acquired acute kidney injury

Background and hypothesis: Causes and risk factors for community-acquired acute kidney injury (CA-AKI) have not been thoroughly studied. The aim of this study was to examine the risk factors for CA-AKI. Methods: In this prospective study, we examined serum creatinine from all individuals visiting a university hospital's emergency department (ED) over an 11-month period for the presence of AKI defined according to the KDIGO criteria. Patients with AKI were invited to participate. Randomly selected controls (1:2) were paired according to age, sex, and date of admission. Participants answered questions about their medical history and medication use, including over-the-counter (OTC) drugs. Conditional logistic regression was used to identify factors associated with AKI. Results: Of 602 AKI cases identified, 512 participated in the study. AKI cases were significantly more likely than controls to have used nonsteroidal anti-inflammatory drugs (NSAIDs) (26.0 % vs 18.0 %, p = 0,001) in the week preceding the ED visit, particularly OTC NSAIDs (23.3 % vs 15.9 %, p < 0.001). AKI was associated with a recent history of vomiting (OR 2.52 [95 %CI 1.87-3.39]), diarrhea (1.30 [1.00-1.70]) and urinary retention (1.92 [1.36-2.72]), use of non-selective NSAIDs (1.84, [1.37-2.48]), RAAS blockers (1.63 [1.21-2.19]), and diuretics (1.53 [1.13-2.08]), and a history of diabetes (1.42 [1.04-1.94]), CKD (1.36 [1.01-1.83]) and smoking (1.72 [1.24-2.37]). Conclusions: Events in the setting of acute illness and medication use, including OTC NSAIDs, may play a greater role in the development of CA-AKI than comorbid conditions. Frequent use of OTC NSAIDs is a concern and should be addressed in view of serious adverse effects.