For many minorities living in an overpopulated neighborhood can be fatal to one's health.

Research conducted by lead author Renee Y. Hsia, MD, assistant professor of emergency medicine at University of California, San Francisco, found that overcrowding in hospital emergency room affects racial and ethnic minorities more than non-minorities.

Not only are many hospitals in highly populated minority neighborhoods lacking in the number of emergency services, but also ambulance diversion is another important factor which can affect one's health. Ambulance diversion occurs when a hospital's emergency department is too busy to accept any new patients. Ambulances are then rerouted to the next available emergency department.

“If you pass by a closer hospital that is on diversion for a hospital 15 minutes down the road, you are increasing the amount of time the patient is in a compromised situation,” Hsia said. “It puts these patients at higher risk for bad health outcomes from conditions like heart attacks or stroke, where minutes could mean the difference between life and death.’’

The research assessed 202 California hospitals in 20 different counties. These emergency departments allowed ambulance diversion, and were critical, non-federal hospitals operating in 2007. Pediatric and county hospitals were excluded from the study.

The data obtained displayed 92 percent of the hospitals allowed ambulance diversion for an average of 347 hours throughout the course of the year. Of those hospitals who serve a high population of minorities, were on ambulance diversion for 306 hours, whereas neighborhood with a smaller quantity of minorities were on ambulance diversion for 75 hours.

“Because ambulances typically transport patients needing true emergency care, diversion reroutes the neediest patients away from their nearest hospital, representing a failure of the systems to provide the intended care,’’ the authors wrote.

However, data did reveal ambulance diversion did not apply to certain injuries such as trauma patients.

According to Hsia, emergency departments and trauma centers are closing down—too often— in areas that need it the most. Hsia and her colleagues recommend a systemic reform that includes better management of hospital flow and statewide principles regulating diversion policies.

The study was published in the Health Affairs.