WASHINGTON, Dec. 6, 2012 /PRNewswire-USNewswire/ -- Patients admitted to the hospital from the emergency department during periods of high crowding died more often than similar patients admitted to the same hospital when the emergency department was less crowded. Crowding was also associated with longer overall hospital length of stay and increased costs per admission, according to the results of a study published online yesterday in Annals of Emergency Medicine ("Impact of Emergency Department Crowding on Outcomes of Admitted Patients") http://tinyurl.com/ardf3wp. (Logo: http://photos.prnewswire.com/prnh/20100616/DC22034LOGO-d) "ER crowding is dangerous," said lead study author Benjamin Sun, MD, MPP, of Oregon Health & Science University in Portland. "We looked at nearly a million admissions through emergency departments across California, a large number of patients. Crowding was associated with 5 percent greater odds of inpatient death." Researchers analyzed 995,379 emergency department visits resulting in admission to 187 hospitals. Daily ambulance diversion – the practice of closing an ER to ambulances because it is too crowded to accept new patients – was the measure of emergency department crowding. Admission to the hospital from the ER on days with prolonged ambulance diversion (a median of 7 hours) – or high emergency department crowding – was associated with 5 percent increased odds of dying in the hospital compared to admissions on days with low ambulance diversion (a median of 0 hours). Patients who were admitted on days with high emergency department crowding had 0.8 percent longer hospital stays and 1 percent increased costs per admission. Periods of high emergency department crowding were associated with 300 excess inpatient deaths, 6,200 hospital days and $17 million in costs. "Emergency department crowding is likely to become worse in the future because of the volume, complexity and acuity of emergency patients," said Dr. Sun. "Policymakers should address ER crowding as an important public health priority."