The finding came from a five-year study of homeless adults who received treatment from the Boston Health Care for the Homeless Program. But its broad conclusions apply to homeless populations in many urban parts of the United States, the study's author and homeless advocates said.

The tripling in the rate of death by drug overdose reflects an overall rise in pain-killer abuse, said Dr. Travis Baggett of Massachusetts General Hospital, the lead author of the study, to be published next month in the journal JAMA Internal Medicine.

"This trend is happening across the country, in non-homeless populations too," Baggett said. "Homeless people tend to experience in a magnified way the health issues that are going on in the general population."

The study, which tracked 28,033 homeless adults from 2003 through 2008, found that of those who died, 17 percent died of drug overdoses, while 6 percent died of causes related to HIV, the virus that causes AIDS.

That is a rough reversal of the trend found in a similar study 15 years earlier, when 6 percent of deaths were due to drug overdose and 18 percent due to AIDS.

After the drug overdoses, the second- and third-leading causes of death in the most recent study were cancer and heart disease, which each accounted for about 16 percent of the deaths.

Homeless people are significantly more likely to die in a given year than their peers in the rest of the population, with those aged 25 to 44 nine times more likely, and those aged 45 to 64 four-and-a-half times more likely to die, the study said.

The decline in AIDS-related deaths reflected an overall decline in infection rates, as well as improvement in care and services for patients since the prior study, which was conducted during the peak years of the U.S. AIDS epidemic.

REGIONAL VARIATIONS

The study looked at a small slice of the roughly 2.3 million to 3.5 million Americans who go through a period of homelessness each year, according to data from the Urban Institute.

While drug abuse is not an uncommon problem among homeless people, the drugs most commonly used vary by region. Heroin and opiate pain-killers are the most available and most used drugs along the coasts, while methamphetamine is more common through the middle of the country and prescription pain-killers tend to be abused around large military bases, said Neil Donovan, executive director for the National Coalition for the Homeless.

"Fifteen years ago we were talking about homeless people drinking Listerine and that being a leading indicator, and now it's Oxycontin and heroin and it's a very different reality," said Donovan, whose group was not involved in the study.

Prescription painkiller abuse is somewhat more common in Boston than other cities due to the high concentration of hospitals and doctors, which make it easier for users to gain access to the drugs, he said.

CHANGES IN TREATMENT

The rise in deaths related to drug overdoses prompted the Boston Health Care for the Homeless Program to change the way it approaches care, said Dr. Jessie Gaeta, the group's medical director.

"We have to become expert in integrating addiction services into the rest of medical care," Gaeta said. "We have decided to take a very thoughtful and critical look at the way that we prescribe these opiods."

The nonprofit group is considering changes, including reducing the overall amount of pain-killers it prescribes and providing patients with another drug, naloxone, which can be used as an antidote to overdose, Gaeta said.

Chronic pain, related to causes ranging from cancer to arthritis, is a common problem among the homeless and the group's doctors continue to prescribe pain-killers to some of their regular patients, Gaeta said. They have stepped up their efforts to counsel those patients on properly using their drugs and also how to protect them from being stolen.

The relationship between homelessness and drug abuse is a self-reinforcing one, advocates noted. Drug abuse can increase the odds of a person becoming homeless, by making it more likely that they lose a job or fall out with family members, and also makes it harder for the homeless to find shelter, as some agencies will not house drug users.

"It's easier to be clean and sober in a bed than on the streets," said Donovan.

(Reporting by Scott Malone; Editing by Sofina Mirza-Reid and Dan Grebler)

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