Acute Kidney Injury in Older Adults

TLDR

Aging kidneys lose autoregulatory capacity, making older adults more susceptible to acute kidney injury, which is linked to higher mortality, chronic kidney disease progression, and functional decline, yet creatinine is an inadequate marker and the incidence is rising without sufficient geriatric‑focused research. This review aims to examine existing literature on acute kidney injury in older adults, identify knowledge gaps, and propose research questions to better integrate geriatric considerations into future mechanistic and clinical studies. The authors conduct a systematic literature review, synthesizing current evidence, highlighting gaps, and formulating potential research questions to guide future investigations.

Abstract

Aging kidneys undergo structural and functional changes that decrease autoregulatory capacity and increase susceptibility to acute injury. Acute kidney injury associates with duration and location of hospitalization, mortality risk, progression to chronic kidney disease, and functional status in daily living. Definition and diagnosis of acute kidney injury are based on changes in creatinine, which is an inadequate marker and might identify patients when it is too late. The incidence of acute kidney injury is rising and increases with advancing age, yet clinical studies have been slow to address geriatric issues or the heterogeneity in etiologies, outcomes, or patient preferences among the elderly. Here we examine some of the current literature, identify knowledge gaps, and suggest potential research questions regarding acute kidney injury in older adults. Answering these questions will facilitate the integration of geriatric issues into future mechanistic and clinical studies that affect management and care of acute kidney injury.