Clinical Interventions in Aging (Jun 2017)
The impact of transient and persistent acute kidney injury on short-term outcomes in very elderly patients
Abstract
Qinglin Li,1 Meng Zhao,2 Xiaodan Wang1 1Department of Geriatric Nephrology, 2Department of Clinical Data Repository, Chinese PLA General Hospital, Beijing, People’s Republic of China Objectives: Acute kidney injury (AKI) is a common complication in elderly patients and is associated with poor outcomes. However, the effect of transient and persistent geriatric AKI on short-term mortality is unclear. We aimed to study the incidence, clinical characteristics, and prognostic impact of transient and persistent AKI in such patients.Methods: We retrospectively enrolled very elderly patients (≥75 years) from the geriatric department of the Chinese PLA General Hospital between 2007 and 2015. AKI was defined according to the 2012 Kidney Disease: Improving Global Outcomes criteria. AKI patients were divided into transient or persistent AKI groups based on their renal function at 3 days post-AKI. Renal function recovery was defined as a return to the baseline serum creatinine (SCr) levels.Results: In total, 668 geriatric patients (39.0%) experienced AKI, and 652 satisfied the inclusion criteria. Of these 652 patients, 270 (41.4%) had transient AKI, and 382 (58.6%) had persistent AKI. The 90-day mortality was 5.9% in patients with transient AKI and 53.1% in patients with persistent AKI. Multivariate analysis revealed that low hemoglobin levels (odds ratio [OR] =0.989; 95% CI: 0.980–0.999; P=0.025), low mean aortic pressure (OR =0.985; 95% CI: 0.971–1.000; P=0.043), peak SCr (OR =1.020; 95% CI: 1.015–1.026; P<0.001) levels, high uric acid (OR =1.002; 95% CI: 1.000–1.003; P=0.040) levels, high blood urea nitrogen (OR =1.028; 95% CI: 1.000–1.056; P=0.047) levels, and mechanical ventilation requirements (OR =1.610; 95% CI: 1.012–2.562; P=0.044) were associated with persistent AKI. Persistent AKI (hazard ratio [HR] =5.741; 95% CI: 3.356–9.822; P<0.001) and more severe AKI stages (stage 2: HR =3.363; 95% CI: 1.973–5.732; P<0.001 and stage 3: HR =4.741; 95% CI: 2.807–8.008; P<0.001) were associated with 90-day mortality.Conclusion: AKI is common in very elderly patients, with transient renal injury representing close to 42% of all cases of geriatric AKI. More frequent SCr measurements may be helpful for the early diagnosis of transient geriatric AKI. Persistent geriatric AKI is independently associated with a significantly higher risk of 90-day mortality. Keywords: acute kidney injury, very elderly, short-term mortality, transient and persistent, risk factors
