One in 10 Cardiac Surgery Patients Develop Persistent Opioid Use

Batya Swift Yasgur MA, LSW

June 25, 2020

Almost one-tenth of patients who underwent cardiothoracic surgery and were prescribed opioids on discharge continued to take them for at least 3 months, a new study shows.

Investigators retrospectively examined data on close to 36,000 patients who underwent cardiothoracic surgery, including coronary artery bypass grafting (CABG) and heart valve procedures. They found that almost 10% had persistent opioid use and were continuing to take opioids 90 to 180 days after surgery.

In particular, patients who underwent a CABG procedure who were female, younger, had increased comorbidities, and were taking preoperative benzodiazepines and muscle relaxants were at highest risk for being opioid dependent after surgery.

Having a history of chronic pain almost tripled the risk of developing new persistent opioid use, as did higher amounts of opioids prescribed to patients at discharge.

"Cardiac surgeons should try to perform more minimally invasive procedures and techniques, use more long-term local anesthetics to decrease the early postoperative pain, and to extubate and mobilize patients as quickly as possible postoperatively," lead author Chase Brown, MD, MSHP, and senior author Nimesh Desai, MD, PhD, Division of Cardiac Surgery, Hospital of the University of Pennsylvania, Philadelphia, told | Medscape Cardiology in an e-mail.

"Furthermore, as we have shown in our study, we should decrease the amount of opioids prescribed to patients at discharge," he said.

The study was published online June 17 in JAMA Cardiology.

"Maximal" Procedures

It is known from the literature that about 3% of patients who undergo elective general surgery procedures become persistent opioid users 3 to 6 months after surgery; however, this has never been studied among patients undergoing more maximal operations, such as cardiac surgery, Brown and Desai said.

"Cardiac surgery is invasive and requires going in through the breastbone, and patients use opioids postoperatively for pain control; thus, we hypothesized that the percentage of patients who are persistent opioid users after surgery who never took opioid preoperatively would be much higher than 3%," they wrote.

"It was our goal to study this issue to determine what percentage of patients undergoing cardiac surgery…were opioid-dependent and continuing to take opioids 3 to 6 months after surgery — a time point when all patients should no longer be having pain from the procedure," they reported.

To investigate the question, the researchers drew on data from a national administrative claims database from January 1, 2003 to December 21, 2016 (n = 31,817 patients), who underwent either CABG or heart valve procedures (n = 25,673 and 10,144, respectively) and had not taken opioids in the 6 months prior to their surgery.

To enable comparison of different opioid medications, they converted the opioid doses into an oral morphine equivalent (OME), "which standardizes each opioid drug to an equianalgesic dosage."

Opioid dependence, defined as filling an opioid prescription in the first 14 days after the procedure and then 90 to 180 days after the index cardiac procedure, was the primary outcome.

Increased Postoperative Pain With CABG

Compared with patients who underwent CABG and did not have persistent opioid use (n = 23,064), those who underwent CABG and had persistent opioid use (n = 2,609) were slightly older (mean age, 62.9 vs 61.6 years) and more frequently male (81.3% vs 76.6%).

In patients who underwent heart valve procedures, compared with patients who did not have persistent opioid use (n = 9343), those with persistent opioid use (n = 821) were also older (mean age, 63.2 vs 61.2 years) and more frequently male (68.3% vs 62.2%).

Persistent opioid use was seen in 9.6% of all patients and was more likely in those undergoing CABG, compared with those who underwent heart valve procedures (10.2% vs 8.1%; P < .001).

Risk Factors for Persistent Opioid Use After Cardiac Surgery
Risk Factor Odds Ratio (95% CI)*
CABG vs valve surgery 0.78 (0.70–0.86)
Female sex 1.15 (1.03–1.26)
Younger age 1.02 (1.01–1.02)
Congestive heart failure 1.17 (1.06–1.30)
Diabetes 1.27 (1.15–1.40)
Kidney failure 1.17 (1.00–1.37)
Chronic pain 2.71 (2.10–3.56)
Alcoholism 1.56 (1.23–2.00)
Preoperative benzodiazepines 1.71 (1.52–1.91)
Preoperative muscle relaxants 1.74 (1.51–2.02)
Increased length of hospital stay 1.03 (1.01–1.04)
Discharge to a facility 1.35 (1.12–1.56)
*P < .001 for all

Patients who received a prescription for more than ~300 mg of OMEs at discharge were found to have a significantly increased risk for dose-dependent new persistent opioid use, compared with those with lower-dosage prescriptions.

"For reference, we found that when patients were prescribed more than 40 tablets of 5 mg oxycodone, patients were at much greater risk of persistent opioid use 90 to 180 days after surgery," Brown and Desai reported.

A CABG procedure involves more trauma to the chest wall, compared with a heart valve procedure, which "most certainly causes increased postoperative chest pain," thereby raising the risk for increased likelihood for persistent opioid use, they noted.

Preoperative Education

Commenting on the study for | Medscape Cardiology, Alexander A. Brescia, MD, MSc, integrated cardiothoracic surgery resident, University of Michigan, Ann Arbor, said the take-home message "is that the amount of opioids prescribed after surgery may have a direct impact on the risk that patients develop persistent opioid use, although the risk is multifactorial."

"As the authors point out, the cardiothoracic community should enact evidence-based protocols to minimize postoperative opioid prescriptions and use multimodal analgesia techniques," added Brescia, who is also a health services research fellow at the Center for Healthcare Outcomes and Policy, University of Michigan, and was not involved with the study.

An accompanying editorial by Steven Farmer, MD, PhD, et al suggests that there is a "need to educate clinicians about the magnitude of the risk [for persistent opioid use], the need for more comprehensive risk factor screening for opioid dependency, and the need for lower-risk pain management options."

Brown and Desai noted that managing postoperative pain without opioids "starts with preoperative education to set realistic goals about postoperative pain."

They acknowledged that some patients may need opioids at discharge "for a limited time for pain control," which is why "setting pain goals before the surgery is very crucial and is an area of future research at our institution."

Brown is supported by the National Research Service Award postdoctoral fellowship. Brown, Desai, the study coauthors, Farmer, the editorial coauthors, and Brescia report no conflicting financial relationships.

JAMA Cardiol. Published online June 17, 2020. Abstract, Editorial


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