Health care providers in Maine wrote prescriptions for a commonly abused type of painkiller at the highest rate in the nation in 2012, according to a new federal report that found wide variations in prescribing patterns across the U.S.

State officials noted that since then, the number of Mainers in treatment for painkiller addiction has dropped significantly, thanks to broad efforts to better manage prescribing practices.

For every 100 Maine residents, health providers wrote 21.8 prescriptions in 2012 for long-acting or extended-release opioid pain relievers, which are more prone to abuse than other painkillers, according to the CDC report released Tuesday. That rate put Maine at the top of the list nationally, just barely outpacing Delaware, at 21.7 per 100 residents.

Maine’s rate was more than five times that of Texas, which had the lowest rate at 4.2.

Dr. Kevin Flanigan, medical director for the MaineCare program, said he couldn’t explain why Maine topped the list, other than the state’s decade-long struggle with opioid drug abuse.

“It is not a surprise for us to be leading the pack for any category of use of opioids,” he said.

Nationally, health care providers wrote 259 million prescriptions in 2012 for opioid painkillers, such as OxyContin, Vicodin and Percocet, the CDC report found. That’s enough to put a bottle of pills in the hands of every adult in the country.

“Prescription drug overdose is epidemic in the United States,” CDC Director Tom Frieden said in a news release. “All too often, and in far too many communities, the treatment is becoming the problem. Overdose rates are higher where these drugs are prescribed more frequently. States and practices where prescribing rates are highest need to take a particularly hard look at ways to reduce the inappropriate prescription of these dangerous drugs.”

Rates of chronic pain and other illnesses don’t vary enough from state to state to account for the differences, public health officials said. High prescribing rates may point to abuse of the drugs.

Maine ranked 25th in the nation for prescription rates for opioid painkillers more generally. For every 100 Maine residents, health care providers wrote 85 prescriptions for opioid painkillers in 2012.

The highest rates were in the Southeast, led by Alabama, where providers wrote 143 prescriptions for every 100 residents.

Maine ranked 11th nationally for per capita prescription rates of high-dose opioids.

MaineCare adopted new policies governing pain management in January 2013, including requiring chronic pain patients to try alternative therapies and limiting their daily painkiller dosing. The program also restricts patients to two weeks of opioid painkillers during a year, unless a doctor justifies a longer treatment period.

Those changes slashed the number of opioid pills prescribed to MaineCare recipients by 6 million, from 22 million in 2012 to 16 million in 2013, Flanigan said. The trend has continued into this year and private insurers have shown interest in following MaineCare’s lead, he said.

The number of Mainers in treatment for opiate and painkiller addiction dropped from 4,180 in 2012 to 3,441 last year, according to the Maine Department of Health and Human Services.

Among MaineCare patients, prescribed opiate medications fell 17 percent from 2012 to 2013, the DHHS data showed. For patients with private insurance, opioid prescriptions dropped 6 percent, but jumped 33 percent among Mainers covered by Medicare.