Acute kidney injury: still deadly 10 years later

Recurrent acute kidney injury in elderly patients is common and associated with 1-year mortality

BACKGROUND

Acute kidney injury (AKI) is common among elderly patients after a first hospitalized AKI. Patients who recover are at risk for recurrence, but recurrent geriatric AKI is not well-studied.

METHODS

This was a retrospective, 12-month cohort study using data from the National Clinical Research Center for Geriatric Diseases. Recurrent AKI was defined as a new spontaneous rise of ≥ 0.3 mg/dl (≥ 26.5 µmol/L) within 48 h or a 50% increase in serum creatinine (Scr) from the baseline within 7 days after the previous AKI episode. The outcome measured was 12-month mortality.

RESULTS

Among 1711 study patients, 652 developed AKI. Of the 429 AKI survivors in whom recovery could be assessed, 314 patients recovered to their baseline renal function, and 115 patients developed chronic kidney disease (CKD). Of the group that recovered renal function, 90 patients (28.7%) subsequently developed recurrent AKI, while 224 (71.3%) did not. Of the 429 survivors with AKI, 103 patients (24.0%) died within 12 months. Multivariate logistic regression analysis revealed that recurrent AKI was significantly associated with coronary disease (odds ratio [OR = 2.008; 95% confidence interval [CI] 1.024-3.938; P = 0.042), a need for mechanical ventilation (OR = 2.265; 95% CI 1.267-4.051; P = 0.006) and high blood urea nitrogen levels (OR = 1.036; 95% CI 1.002-1.072; P = 0.040) at the first AKI event. Kaplan-Meier curves showed the 12-month survival of patients with non-recurrent AKI was better than that of patients with CKD, and survival of patients with recurrent AKI was worse than that of patients with CKD (log rank P < 0.001). In the multivariate Cox regression analysis, mortality at 12 month was higher in the patient with recurrent AKI as compared with those with a single episode (HR = 3.375; 95% CI 2.241-5.083; P < 0.001).

CONCLUSION

Recurrent AKI is common among elderly patients who recovered their renal function post-AKI and is associated with significantly higher 12-month mortality compared with CKD patients.

Serum Sodium Levels Predict Mortality in Elderly Acute Kidney Injury Patients: A Retrospective Observational Study

Purpose

We examined the relationship between different levels of serum sodium and mortality among elderly patients with acute kidney injury (AKI).

Methods

We retrospectively enrolled elderly patients from Chinese PLA General Hospital from 2007, to 2018. All-cause mortality was examined according to eight predefined sodium levels: <130.0 mmol/L, 130.0–134.9 mmol/L, 135.0–137.9 mmol/L, 138.0–141.9 mmol/L, 142.0–144.9 mmol/L, 145.0–147.9 mmol/L, 148.0–151.9 mmol/L, and ≥152.0 mmol/L. We estimated the risk of all-cause mortality using a multivariable adjusted Cox analysis, with a normal sodium level of 135.0–137.9 mmol/L as a reference.

Results

In total, 744 patients were suitable for the final evaluation. After 90 days, the mortality rates in the eight strata were 36.1, 27.8, 19.6, 24.4, 30.7, 48.6, 52.8, and 57.7%, respectively. In the multivariable adjusted analysis, patients with sodium levels <130.0 mmol/L (HR: 2.247; 95% CI: 1.117–4.521), from 142.0 to 144.9 mmol/L (HR: 1.964; 95% CI: 1.100–3.508), from 145.0 to 147.9 mmol/L (HR: 2.942; 95% CI: 1.693–5.114), from 148.0 to 151.9 mmol/L (HR: 3.455; 95% CI: 2.009–5.944), and ≥152.0 mmol/L (HR: 3.587; 95% CI: 2.151–5.983) had an increased risk of all-cause mortality. After 1 year, the mortality rates in the eight strata were 58.3, 47.8, 33.7, 38.9, 45.5, 64.3, 69.4, and 78.4%, respectively. Patients with sodium levels <130.0 mmol/L (HR: 1.944; 95% CI: 1.125–3.360), from 142.0 to 144.9 mmol/L (HR: 1.681; 95% CI: 1.062–2.660), from 145.0 to 147.9 mmol/L (HR: 2.631; 95% CI: 1.683–4.112), from 148.0 to 151.9 mmol/L (HR: 2.411; 95% CI: 1.552–3.744), and ≥152.0 mmol/L (HR: 3.037; 95% CI: 2.021–4.563) had an increased risk of all-cause mortality.

Conclusion

Sodium levels outside the interval of 130.0–141.9 mmol/L were associated with increased risks of 90-day mortality and 1-year mortality in elderly AKI patients.

Predictors of survival after prolonged weaning from mechanical ventilation

PURPOSE

Weaning from mechanical ventilation is a key component of intensive care treatment; however, this process may be prolonged as some patients require care at specialised centres. Current data indicate that weaning from invasive mechanical ventilation is successful in approximately 65% of patients; however, data on long-term survival after discharge from a weaning centre are limited.

MATERIALS AND METHODS

We analysed predictors of survival among 597 patients (392 men, mean age 68 ± 11) post-discharge from a specialised German weaning centre.

RESULTS

Complete weaning from mechanical ventilation was achieved in 407 (57.8%) patients, and 106 patients (15.1%) were discharged with non-invasive ventilation; thus, prolonged weaning was successful in 72.9% of the patients. The one-year and five-year survival rates post-discharge were 66.5% and 37.1%, respectively. Age, duration of mechanical ventilation, certain clusters of comorbidities, and discharged with mechanical ventilation significantly influenced survival (p < .001). Completely weaned patients who were discharged with a tracheostomy had a significantly reduced survival rate than did those who were completely weaned and discharged with a closed tracheostomy (p = .004).

CONCLUSIONS

The identified predictors of survival after prolonged weaning could support therapeutic strategies during patients' intensive care unit stay. Patients should be closely monitored after discharge from a weaning centre.