Epidemiology of acute kidney injury

Background and objectives: The worldwide incidence of acute kidney injury is poorly known because of underreporting, regional disparities, and differences in definition and case mix. New definitions call for revision of the problem with unified criteria. Design, setting, participants, & measurements: This article reports on the research recommendations of an international multidisciplinary committee, assembled to define a research agenda on acute kidney injury epidemiology using a modified three-step Delphi process. Results: Knowledge of incidence and risk factors is crucial because it drives local and international efforts on detection and treatment. Also, notable differences exist between developing and developed countries: Incidence seems higher in the former, but underreporting compounded by age and gender disparities makes available data unreliable. In developing countries, incidence varies seasonally; incidence peaks cause critical shortages in medical and nursing personnel. Finally, in developing countries, lack of systematic evaluation of the role of falciparum malaria, obstetric mechanisms, and hemolytic uremic syndrome on acute kidney injury hampers efforts to prevent acute kidney injury. Conclusions: The committee concluded that epiderniologic studies should include (1) prospective out- and inpatient studies that measure incidence of community and hospital acute kidney injury and post-acute kidney injury chronic kidney disease; (2) incidence measurements during seasonal peaks in developing and developed countries; and (3) whenever available, use of reliable existing administrative or institutional databases. Epidemiologic studies using standardized definitions in community and institutional settings in developing and underdeveloped countries are essential first steps to achieving early detection and intervention and improved patient outcomes.