Updated

Possibly driven by a surge in painkiller abuse, the number of drug and alcohol problems diagnosed by U.S. doctors increased by 70 percent between 2001 and 2009, according to new research.

"We know that increases in prescription drug use are a big part of what's going on nationally. I also think - in our study - the availability of effective treatment is a big part of it as well and likely drawing people into care," said the study's lead author Dr. Joseph W. Frank, from Brigham and Women's Hospital in Boston.

Those treatments include medications such as methadone, as well as talk therapy.

The new study, which used information from two national surveys of doctors' visits, estimated that the number of those visits involving drug or alcohol abuse or addiction increased from 10.6 million between 2001 and 2003 to 18 million between 2007 and 2009.

Over the same span, the number of visits including a diagnosis of opioid painkiller abuse, in particular, increased from 772,000 to 4.4 million - almost a six-fold increase.

Psychiatry researcher Amy Bohnert from the University of Michigan Medical School in Ann Arbor said she's not surprised with the increase in opioid-related visits.

"It is quite a large increase and it does really highlight that this is a substantial problem in terms of this being a growing trend," Bohnert, who wasn't involved in the new research, told Reuters Health.

"This finding is consistent with trends in substance use disorder-related utilization at the nation's community health centers and emergency departments and, sadly, use of its morgues," the study's authors wrote in the Archives of Internal Medicine on Monday.

The Centers for Disease Control and Prevention estimate that 14,800 Americans died of an opioid overdose in 2008 - three times the number of overdose deaths 20 years earlier.

Across the U.S., it's estimated that 22.5 million people are dependent on alcohol or drugs, according to Frank's team.

Bright spot

Despite the large increase in opioid abuse diagnoses, the researchers said their study does provide a "reason for optimism."

Specifically, the number of medicines prescribed to treat drug or alcohol problems during doctors' visits increased by about as much as the number of visits related to opioid abuse.

Those medicines were prescribed to 643,000 people between 2001 and 2003. Between 2007 and 2009, that number grew to 3.9 million people.

The most-prescribed medications were buprenorphine and methadone, which are used to treat people addicted to opioids.

The most popular treatment, however, was talk therapy, which was used in about 25 million total patients during the study period. Its use did not change much over time.

Frank told Reuters Health the findings are a mix of good news and bad news.

"I think it's a mixed bag that highlights the magnitude of the problem and suggests we're heading in the right direction" when it comes to treatment, he said.