Reference
Silveira Santos CG, Romani RF, Benvenutti R et al. Acute Kidney Injury in Elderly Population: A Prospective Observational Study. Nephron. 2018;138(2):104-112. doi: 10.1159/000481181.
At a glance
Acute kidney failure or acute kidney injury (Acute Kidney Injury-AKI) is a complex clinical syndrome caused by the sudden reduction in renal function with a higher prevalence in the elderly population.
The hospital setting is configured as the one in which there is the greatest risk of developing AKI. The severity of AKI is negatively correlated with the outcome of the disease in patients and the most widespread international classification is that shown in the 2012 K-DIGO (stratification in 3 stages, with increasing severity, based on serum creatinine values and/or diuresis).
Kidney damage can be reversible thanks to functional, structural and molecular adaptation phenomena, but it can also progress to chronic kidney disease (CKD) and the need to initiate dialysis. The present study carried out in Brazil, evaluated the characteristics of elderly patients admitted to hospital and the variables associated with the severity of AKI and the therapy required.
What is already known
In recent years, numerous studies have attempted to evaluate the incidence of acute kidney failure or acute kidney injury (Acute Kidney Injury-AKI) in hospitalized patients; the overall results are in agreement in underlining that AKI involves about 8-16% of the hospitalized population. The prevalence of this condition has been increasing over the last few years depending on variables in the general population (gradually increasing age, increase in comorbidities, etc.), the greater ability to recognize AKI and the large number of clinical events occurring. acute that are associated with the decline in renal function (septic shock, cardiogenic shock, etc).
Design and Methods
This is a prospective observational study conducted in Brazil on a sample of 286 elderly patients (defined by the authors as over 60 years of age) hospitalized with a diagnosis of AKI. Several variables were examined: severity of AKI, time elapsed before the nephrological evaluation, execution of hemodialysis treatment, access to ICU wards and outcome of the disease.
Main results
Overall mortality was 53% of the sample; compared to the control group (patients discharged at the end of hospitalization), they recorded a longer hospital stay, an incidence of parenchymal AKI (pathology of the kidney and not secondary to other causes) and a longer duration of AKI, a more severe degree of AKI (especially stage 3) and the need to resort to replacement dialysis treatment. In particular, in a multivariate analysis, the development of parenchymal AKI was associated with the death of the patient with OR 2.88 (95% confidence interval: 1.29 – 6.13). 36.4% of discharged patients who already had chronic kidney disease (CKD) experienced further decline in kidney function.
About 15% of discharged patients had to resort to chronic dialysis treatment and factors that seem to be related to this event were age, severity of acute kidney injury (AKI), presence of previous CKD, diabetes mellitus and the number of hemodialysis sessions performed during AKI.
Limitations
The main limitation of the study is represented by the cut-off to define the elderly population (60 years); in fact, in 2019, Istat defined the new cut-off of 75 years for the elderly Italian population. Furthermore, it is a single center study whose results need to be replicated in other locations.
What’s news
One of the most significant aspects concerns the attempt to analyze AKI in a developing country, precisely to underline how it is a problem that affects the entire world population and like AKI, despite the variability in the identification of the population. elderly, is a condition that affects patients with an older age.
What the Prospects
The study that we have reported, like numerous others published in the literature, is similar to the one we are conducting at the A.O.U. “Maggiore della Carità” of Novara-UPO aimed at highlighting the association between the general aging of the population and a lower ability of the kidney to resist insults (ie use of nephrotoxic drugs, ischemic and / or toxic events), thus determining the reduction of renal function (“Aging Kidney”).
This condition can be transient (with the recovery of kidney function as before the insult itself occurred) or it can result in “maladaptive repair” with progression to chronic kidney disease.
The senile kidney is therefore more exposed to AKI episodes as it decreases its functional reserve (the ability to respond adequately to pathophysiological stresses): predisposition to AKI puts the patient in a condition of greater frailty and an increase in hospitalizations and healthcare costs. Both an adequate nephrological framework with the collaboration of GPs in the area, and an adequate prevention work can lead to the preservation of this renal functional reserve and therefore limit the number and severity of AKI events in the elderly population, improving the clinical outcome and slowing down progression to more severe forms of chronic kidney disease requiring dialysis treatment.
A cura di Umberto Morosini