Weekend Effect and in-Hospital Mortality in Elderly Patients with Acute Kidney Injury: A Retrospective Analysis of a National Hospital Database in Italy

Weekend admissions and outcomes in patients with pneumonia: a systematic review and meta-analysis

Background

To document pooled evidence on the association between weekend hospital admissions and the potential risks of mortality, intensive care requirements, and readmission among patients with pneumonia.

Methods

We performed a systematic search across the PubMed, EMBASE, and Scopus databases. We collected observational studies exploring the association between weekend admissions and outcomes of interest in patients with pneumonia. To analyze the data, we used a random effects model and expressed the effect sizes as pooled odds ratios (ORs) accompanied by their respective 95% confidence intervals (CIs).

Results

The analysis comprised data from 13 retrospective studies. Compared to patients admitted on weekdays, those admitted during the weekend had a non-statistically significant marginally higher risk of in-hospital mortality (OR, 1.02; 95% CI, 1.00, 1.04) but similar 30-day mortality after admission (OR, 1.03; 95% CI, 0.97, 1.10), and similar risks of admission to intensive care unit (OR, 1.04; 95% CI, 0.98, 1.11) and re-admission (OR, 0.85; 95% CI, 0.65-1.12).

Conclusion

Our findings do not support the presence of a "weekend effect" in patients with pneumonia.

Systematic review registration

PROSPERO, identifier CRD42023425802, https://www.crd.york.ac.uk/prospero/.

Weekend Effect on Mortality, Access to Renal Replacement Therapy, and Other Outcomes Among Patients With End-Stage Renal Disease: A Retrospective Analysis of the Nationwide Inpatient Sample

BACKGROUND

A large body of research has been conducted on the "weekend effect," which is the reportedly increased risk of adverse outcomes for patients admitted to the hospital on weekends versus those admitted on weekdays. This effect has been researched in numerous patient populations, including sub-populations of end-stage renal disease (ESRD) patients, with varying conclusions.

OBJECTIVES

To assess whether differences in in-hospital mortality, access to renal replacement therapy (RRT), time to RRT, and other important outcomes exist in patients with ESRD or patients on RRT admitted on the weekend versus weekdays.

DESIGN AND SETTING

A retrospective cohort study was conducted using the 2018 Nationwide Inpatient Sample. Patients were included if they were adults with a principal or secondary diagnosis of ESRD or if they were admitted with a diagnosis related to initiation, maintenance, or complications of RRT. Patients admitted between midnight Friday and midnight Sunday were classified as weekend admissions. Primary outcome measurements included in-hospital mortality, in-hospital dialysis (peritoneal dialysis, hemodialysis, and continuous RRT), and renal transplantation (TP). Secondary outcomes included length of hospital stay (LOS) and total hospitalization charges.

RESULTS

The study included 1,144,385 patients who satisfied the inclusion criteria. Compared with patients admitted on weekdays, patients with ESRD admitted on weekends had 8% higher adjusted odds of in-hospital mortality (OR: 1.08; 95% CI: 1.03-1.13; p = 0.002), 9% lower adjusted OR of any RRT over the weekend than on weekdays (OR: 0.91; 95% CI: 0.89-0.93; p = 0.000), lower RRT rates (within 24 hours) (adjusted OR: 0.71; 95% CI: 0.70-0.73; p = 0.000), higher odds of renal TP (adjusted OR: 1.32; 95% CI: 1.20-1.45; p = 0.000), and higher hospitalization charges (mean adjusted increase: $1451; p = 0.07).

LIMITATIONS

The limitations of the study include the use of retrospective data and an administrative database.

CONCLUSION

Compared with weekday admissions, patients with ESRD admitted on weekends had higher odds of mortality, higher mean hospitalization charges, and higher odds of renal TP. They had lower overall RRT rates, and a longer time to first RRT. However, the average LOS was similar for both weekend and weekday admissions.

Seasonal pattern in elderly hospitalized with acute kidney injury: a retrospective nationwide study in Italy

Purpose

Acute kidney injury (AKI) frequently complicates hospitalization and is associated with in-hospital mortality (IHM). It has been reported a seasonal trend in different clinical conditions. The aim of this study was to evaluate the possible relationship between seasons of the year and IHM in elderly hospitalized patients with AKI.

Methods

We selected all admissions complicated by AKI between 2000 and 2015 recorded in the Italian National Hospital Database. ICD-9-CM code 584.xx identified subjects with age ≥ 65 years and age, sex, comorbidity burden, need of dialysis treatment and IHM were compared in hospitalizations recorded during the four seasons. Moreover, we plotted the AKI observed/expected ratio and percentage of mortality during the study period.

Results

We evaluated 759,720 AKI hospitalizations (mean age 80.5 ± 7.8 years, 52.2% males). Patients hospitalized with AKI during winter months had higher age, prevalence of dialysis-dependent AKI, and number of deceased patients. In whole population IHM was higher in winter and lower in summer, while the AKI observed/expected ratio demonstrated two peaks, one in summer and one in winter. Logistic regression analysis demonstrated that parameters such as age, autumn, winter, comorbidity burden were positively associated with IHM.

Conclusion

We conclude that a seasonality exists in AKI, however, relationship between seasons and AKI could vary depending on the aspects considered. Both autumn and winter months are independent risk factors for IHM in patients with AKI regardless of age, sex and comorbidity burden. On the contrary, summer time reduces the risk of death during hospitalizations with AKI.