SAN DIEGO – Patients hospitalized for hypertensive emergencies had higher mortality and other complications if they were admitted on a weekend instead of on a weekday, results from a large national analysis demonstrated.
Dr. Amit Taneja
Published studies have shown that patients admitted with acute myocardial infarction, stroke, and GI bleeding tend to have worse outcomes if they’re admitted on a weekend instead of on a weekday – the so-called weekend effect, Dr. Amit Taneja said at the annual congress of the Society of Critical Care Medicine. Possible reasons for this association, he continued, include the fact that hospital staffing fluctuates around the clock and throughout the week and that fewer medical and paramedical staff are present on weekends, resulting in decreased and possibly delayed access to radiology, interventions, and procedures on Saturday and Sunday.
"With that background, we hypothesized that patients admitted with hypertensive emergencies over the weekends have worse outcomes, when compared to those admitted on weekdays," said Dr. Taneja of the division of pulmonary and critical care medicine at the Medical College of Wisconsin, Milwaukee.
To test this hypothesis, he and his associates evaluated the Nationwide Inpatient Sample database from 2000 through 2008 to identify patients discharged with a primary diagnosis of hypertensive emergency based on International Statistical Classification of Diseases, 9th Revision, Clinical Modification codes 401.0, 402.00, 402.01, 403.00, 403.01, 404.00. 404.01, 404.02, 404.03, 405.01, and 405.09. They defined weekend admissions as those that occurred between midnight Friday and midnight Sunday. The primary outcome was hospital mortality.
The researchers used chi-square analysis and t tests to compare variables for unadjusted analysis. They used multivariate logistic regression to obtain odds ratios and adjusted for age, demographics, hospital characteristics, and the Elixhauser comorbidity index.
Dr. Taneja reported that of the 1,213,109 patients discharged with a hypertensive emergency, 264,587 (21.8%) were admitted on a weekend, while the remainder (948,522 or 78.2%) were admitted on a weekday.
An adjusted analysis revealed that patients who were admitted on a weekend had a significantly higher mortality, compared with those who were admitted on a weekday (3.11% vs. 2.54%, respectively), for an absolute increase in mortality of 0.57%. This translated into one excess death on weekend admission for every 175 discharges.
The association persisted on multivariate analysis, which determined that the odds of mortality were 1.16 times higher for patients who were admitted on a weekend, compared with those who were admitted on a weekday.
Dr. Taneja and his associates also observed that it took longer for patients admitted on a weekend to undergo certain procedures, compared with patients who were admitted on a weekday. For example, 40% of patients with aortic dissection who were admitted on a weekend underwent surgery on the first day of admission, compared with 51% of their counterparts who were admitted on a weekday.
Dr. Taneja acknowledged certain limitations of the study, including its retrospective design and the potential for ICD coding errors. Also, "assessment of severity of disease may be inaccurate due to unmeasured confounders," he said. "Further studies are needed to look into this weekend effect."
Dr. Taneja said that he had no relevant financial conflicts to disclose.