WEDNESDAY, Jan. 29, 2020 (HealthDay News) -- Nearly half of all opioid doses and more than a quarter of all opioid prescriptions in the United States come from 1% of health care providers, a new study says.

The authors said this suggests that efforts to reduce overuse of prescription opioid painkillers should not focus on strict limits for all doctors but on a small percentage.

"Most prescriptions written by the majority of providers are below recommended thresholds, suggesting that most U.S. providers are careful in their prescribing," they wrote in the study published Jan. 29 in BMJ.

"However, a small portion of providers account for a highly disproportionate proportion of opioids," they said in a journal news release.

Keith Humphreys, a professor of psychiatry and behavioral sciences at Stanford University, led the study.

His team analyzed prescribing data from a private insurance provider from 2003 to 2017 that covered more than 60 million people in all 50 U.S. states and Washington, D.C.

During that time, an annual average of 8.2 billion standard doses of opioids in morphine milligram equivalents (MMEs) were prescribed by nearly 670,000 providers to 3.9 million patients, the study found.

In 2017, the top 1% of providers accounted for 49% of all opioid doses and 27% of all opioid prescriptions. Those providers prescribed an average of 748,000 MMEs -- nearly 1,000 times more than the middle 1% of providers.

At least half in the top 1% were at that level for more than one year, the study found.

Guidelines recommend that new opioid prescriptions for acute pain not exceed 50 MMEs a day for seven days. The researchers found that more than two-fifths of prescriptions from the top 1% of providers exceeded 50 MMEs a day and more than four-fifths exceeded a week's duration.

The study was observational and Humphreys and his team said they were not able to assess the appropriateness of any prescription. Also, their data may not apply to the entire United States.

But in light of the current opioid crisis in America, they urged officials to focus on the top 1% of providers to reduce opioid prescribing. U.S. levels are far higher than in other countries.

Other strategies to reduce prescribing include improving patient care, managing patients with complex pain, and reducing other health problems, researchers added.

More information

The U.S. National Institute on Drug Abuse has more about prescription opioids.