At a time of rising rates of opioid overdose and addiction, new research has revealed that doctors in the US received payments of over $46 million in less than one-and-half years.

One in 12 physicians -- and nearly one in five family medicine physicians -- accepted payments from pharmaceutical companies related to opioids, according to the study published online in the American Journal of Public Health.The findings suggest that pharmaceutical companies may have a stronger hold than previously known on how doctors prescribe the powerful drugs. Using US Centers for Medicare and Medicaid Services data, the researchers identified 375,255 non-research, opioid-related payments to 68,177 physicians between August 2013 and December 2015 totalling over $46 million. 

"Even though most payments were small, they add up to a shocking number and may have a wide-reaching influence on physician behaviours," said lead researcher Scott Hadland, pediatrician and adolescent addiction specialist at the Grayken Center for Addiction Medicine at Boston Medical Center in the US."We need to take a hard look at how the pharmaceutical industry may be influencing care and prescribing at the ground level," Hadland said. Payments were defined as "transfers of value" -- which could be direct money to physicians, a reimbursement for travel, speaking or consulting fees, education or meals.The average payment to physicians was $15, with most receiving one payment per year.

However, the top one per cent of doctors collectively received more than $38 million (82 per cent of the total) and averaged more than $2,600 in yearly payments during the study period.Speaking fees accounted for the largest amount of payments and food/beverage payments were the most frequent. Anesthesiologists received the most in total annual payments, but the largest number of payments went to family medicine physicians, according to the study.The Physician Payment Sunshine Act, passed under the Affordable Care Act in 2010, requires drug companies to report all payments to physicians in the US.