NEW HAVEN — So-called “superusers” of Emergency Medical Services (EMS)— most of whom had alcohol-related reasons for their EMS transport — generated millions of dollars in medical costs in one year alone in the city of San Francisco, according to a new study by the Yale School of Medicine and the University of California-San Francisco (UCSF). The study, which focuses on the financial impact of alcohol abuse on one urban community, appears in the journal Prehospital Emergency Care.

Researchers from the Emergency Department at Yale and UCSF identified 100 EMS superusers — individuals who used EMS services in San Francisco more than 15 times in the year 2009. Yale first author M. Kennedy Hall and colleagues found that superusers were significantly younger and more likely to be male than other EMS users. The majority of superusers had Medicaid coverage. Also, superusers were more than eight times more likely to have an alcohol-associated reason for an EMS encounter than people who used EMS only once that year.

Although the EMS superuser group comprised only 0.3 percent of the total number of individuals who used EMS, they generated 6.1 percent of the transports, as well as a disproportionate share of estimated charges — $3.8 million for that year — reimbursed primarily through public insurance programs.