The “weekend effect” is the finding of a difference in mortality rate for weekend admissions vs. weekday admissions, believed to be due to lower hospital staffing. Data on this effect for diabetic ketoacidosis (DKA), which is responsible for more than 100,000 hospital admissions per year in the US, is not available. Therefore, it is our aim to assess the differences in outcomes of weekend versus weekday admissions for DKA.
Data from the National Inpatient Survey (NIS) database from 2011 to 2014 was reviewed. Patients with primary or secondary diagnosis of DKA on admission were identified by ICD-9 codes (250.1 and 250.3). Patients’ baseline characteristics and comorbidities were abstracted. The Charlson Comorbidity Index (CCI) was calculated for each patient. We compared baseline characteristics, comorbidities, mortality, length of stay, and complications of DKA between weekend and weekday admissions. Statistical analysis was done using student's t-test, chi-square test, and binary logistic regression with level of α set at 0.05.
Between 2011 and 2014, there were 14,059 DKA admissions on weekdays vs. 4950 admissions on weekends. The mean LOS was shorter for weekday admissions compared to weekend ones, but it was not significant (4.14 days vs. 4.35 days, p=0.09). Compared with patients admitted on weekdays, those admitted on weekends had an increased risk of death (4.6% vs. 3.3%, p5 was observed in weekend admissions vs. weekday ones (7.6% vs. 6.3%, p<0.05). After adjusting for CCI, sex, and hospital setting, the weekend admission remained an independent predictor of increased mortality (OR, 3; 95% CI, 1.68-7.3; p<0.001). The DKA complications rate in weekday admissions vs. weekend ones were as follows: Cerebral edema 0.17% vs. 0.2% (p=0.42), pulmonary edema 0.1% vs. 0.1% (p=0.57), altered mental status 1.9% vs. 1.7% (p=0.2), venous thrombosis 0.2% vs. 0.2% (p=0.56), pancreatitis 4% vs. 3.9% (p=0.34), pneumonia 5.5% vs. 6.3% (p=0.26) and aspiration 2.9% vs. 3.2% (p=0.16).
Patients admitted to hospitals for DKA during weekends had higher mortality rate, but mean LOS and complication rates were similar in two groups. Although, patients admitted on weekends had higher CCI scores, this does not appear to mediate the “weekend effect” for mortality. The difference is likely due to lower availability of medical, nursing and other health professional staff at weekends.
Patients admitted to hospital diagnosed with DKA during weekends have a higher mortality rate compared to those admitted on weekdays.
Yasaman Motlaghzadeh– Internal Medicine Resident, Rutgers-New Jersey Medical School, West Orange, New Jersey
Justin Mathew– Internal Medicine chief Resident, Rutgers- New Jersey Medical School
Genevieve Matthews– Chief Resident, Rutgers-New Jersey Medical School
Mirela Feurdean– Program director, Internal Medicine Residency Program, Rutgers- New Jersey Medical School, New Jersey
Internal Medicine Resident
Rutgers-New Jersey Medical School
West Orange, New Jersey
MD-MPH Degree: Tehran University Of Medical Sciences, Internal Medicine Residency: Rutgers- New Jersey Medical School
Internal Medicine chief Resident
Rutgers- New Jersey Medical School
Internal Medicine residency: Rutgers -New Jersey Medical School
Rutgers-New Jersey Medical School
Chief Resident , Rutgers-New Jersey Medical School