Opioid Prescription Rates Vary Following Knee Surgery, Higher Strength Doses Remain Common

By analyzing a large, national database of insurance claims, researchers have found that 36% of patients received an opioid prescription that was stronger than the CDC-recommended dose following a knee surgery, according to a study published in BMJ Open.

The findings suggest that dangerous prescribing practices could be contributing to the opioid epidemic, according to the study authors. Giving a high-dosage prescription to patients who have never taken opioids before may be associated with long-term opioid use, more leftover pills, and even higher rates of overdose among family members, according to the study.

The investigators focused on arthroscopic knee surgeries because they are in the top 3 most common outpatient procedures in the United States. They used a national database of insurance claims to identify nearly 100,000 patients who had arthroscopic knee surgery and who had not used any opioid prescriptions in the 6 months before their surgery.

Based on their analysis, the investigators found that 72% of patients filled an opioid prescription within 3 days of their surgery. They found little variation in the fill-rate between non-invasive surgeries and invasive procedures, which require cutting or drilling into bone. Notably, however, they did find significant differences in prescribing rates from state to state.

High prescription rates, defined as 77% or higher, were found across the Midwest into the Rocky Mountain region, as well as in Arizona and Washington state. Lower rates, below 70%, were found more often in coastal states, the Dakotas, Texas, and others. The study authors also found a wide variation in the number of tablets included in a single prescription, ranging from 24 in Vermont to 45 in Oklahoma.

“We found massive levels of variation in the proportion of patients who are prescribed opioids between states, even after adjusting for nuances of the procedure and differences in patient characteristics,” said senior author M. Kit Delgado, MD, in a press release. “We’ve also seen that the average number of pills prescribed was extremely high for outpatient procedures of this type, particularly for patients who had not been taking opioids prior to surgery.”

Investigators noted that the strength of the typical prescription was 50 milligrams of morphine per day, the level that the CDC has identified as the threshold for increased risk of opioid overdose death. Approximately 25,000 of the patients studied were receiving this dosage level or more.

Although these findings are alarming, the investigators said they present opportunities for policy changes both at the state and organizational levels.

“Some factors that may contribute to state variation are policies, such as mandates to check prescription drug monitoring program data, which have shown to affect the opioid prescribing rate,” said lead author Benjamin Ukert, MD, in a press release. “However, most state policies are aimed at patients with a history of opioid use, and our study focuses on patients who do not have that history. Thus, practice and organizational styles may be more important factors for this population.”

REFERENCE

Opioid Prescription Rates for Knee Surgery Patients Vary, But Higher Strength Dosage Common [news release]. Penn Medicine News; August 25, 2020. https://www.pennmedicine.org/news/news-releases/2020/august/opioid-prescription-rates-for-knee-surgery-patients-vary-but-higher-strength-dosage-common. Accessed August 27, 2020.