A new study posits that healthcare providers who receive gifts from pharmaceutical companies are more likely to prescribe branded drugs.

Medicare Part D prescribers who received gifts from pharmaceutical companies prescribed 7.8% more branded drugs than prescribers who had not received a gift, according to an analysis of data from Washington D.C.’s AccessRx program and 2013 Medicare claims. Thirty-nine percent of prescribers analyzed received gifts in 2013.

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The size of the gift was associated with more costly prescriptions. Those who received large gifts (defined as more than $500 annually) averaged $189 per prescription, while those who received smaller gifts (less than $500) averaged $114 per prescription.  

Gifts were defined as cash, meals, or ownership interests. The study was published in PLOS ONE.

Researchers from Georgetown University Medical Center said their analysis “confirms and expands on previous work showing that industry gifts are associated with more expensive prescriptions and more branded prescriptions.” They added, “Industry gifts influence prescribing behavior, may have adverse public health implications, and should be banned.”

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The research adds to a growing body of evidence that industry gifts may influence prescription habits. A study presented at the 2017 American Society of Clinical Oncology meeting found that oncologists are similarly influenced by gifts. Researchers at the University of North Carolina found that physicians who received a payment  (for meals, travel, or lodging) or speaking or consulting fees were more likely to prescribe cancer drugs marketed by the company that underwrote the payments.

Another 2016 study, which examined 2013 Open Payments data, came to a similar conclusion for Medicare Part D Prescribers. The research, published in JAMA Internal Medicine, found that receipt of meals costing more than $20 was associated with higher prescribing rates for promoted brand name drugs. Researchers cautioned at the time that their findings represented a link between meals and prescribing those companies’ drugs, rather than a cause-and-effect relationship.