Injection-drug use accounts for more than half of all new infections of hepatitis C – a potentially deadly viral illness that infects some 4.4 million Americans, including an estimated 32,000 to 35,000 New Mexicans.
Hepatitis C infections declined by 60 percent among injection drug users who received long-term treatment with methadone or Suboxone, said Kimberly Page, chief of epidemiology, biostatistics and preventive medicine at the UNM School of Medicine.
“Sixty percent is a really huge effect,” said Page, lead author of the study published this week in the online edition of the Journal of the American Medical Association Internal Medicine.
“In fact, if we had a vaccine that had a 60 percent reduction in hepatitis C infections, I guarantee you that would be big news,” she said. “This is the equivalent of a vaccine.”
Methadone and Suboxone, a brand-name drug, both are synthetic opiates used to treat people addicted to opiate drugs such as heroin. The drugs block painful withdrawal symptoms but lack the euphoric effects of other opiates.
In New Mexico, access to treatment is limited both by cost and the small number of programs and providers, particularly in rural areas, said Dr. Miriam Komaromy, an addiction specialist at UNM’s Project ECHO.
The state has a small number of methadone treatment programs concentrated in Albuquerque, Santa Fe and Las Cruces, she said.
New Mexico expanded its Medicaid program in 2012 to cover the cost of methadone, but few programs in the state accept Medicaid payments, she said.
Medicaid also pays for Suboxone, but relatively few physicians prescribe the drug, Komaromy said. About 340 New Mexico physicians are certified to prescribe Suboxone, but only 144 have prescribed it for 10 or more patients in the past year, she said.
Suboxone treatment costs about $15 a day, and methadone, $10 to $15 a day, she said.
The study enrolled 552 injection-drug users in San Francisco from 2000 through August 2013. They had a median age of 23, and most were homeless men who used heroin.
About one-in-four of those studied became infected with hepatitis C within a year, but those on maintenance therapy with methadone or Suboxone showed 60 percent fewer infections, the study found.