Patients prescribed analgesics after ambulatory surgery in anticipation of postoperative pain are more likely to still be opioid users a year later

CLINICAL CONTEXT

According to the current study by Bell and colleagues, little is known about the effect of opioid prescribing on long-term opioid use after short-stay surgery not associated with significant postoperative pain. The most common analgesics prescribed after surgery are opioids and nonsteroidal anti-inflammatory drugs (NSAIDs), but both drug classes are associated with adverse effects. In elderly persons, concerns may arise about these adverse effects in the long term if use after short-stay surgery increases the risk for long-term usage.

This retrospective, nested-cohort study examines the risk for long-term opioid and NSAID use after prescription for these agents after short-stay surgery in older persons.

STUDY SYNOPSIS AND PERSPECTIVE

Patients prescribed analgesics after ambulatory surgery in anticipation of postoperative pain are more likely to still be opioid users a year later, warn researchers.

“Patients receiving an opioid prescription within a week of surgery were 44% more likely to become long-term opioid users compared with those who received no such prescription,” senior investigator Chaim Bell, MD, from St. Michael’s Hospital in Toronto, Ontario, Canada, told Medscape Medical News.

“We looked at older adults not previously prescribed analgesics undergoing low-risk surgeries such as cataract, laparoscopic gallbladder, transurethral resection of the prostate or varicose vein stripping,” Dr. Bell explained.

These low-risk operations are also considered low pain because they are primarily ambulatory and, on the basis of clinical experience, are not generally associated with high levels of postoperative pain, the researchers write.

Dr. Bell pointed out that more detailed discharge instructions for patients and their physicians might be helpful in alleviating this problem.

The retrospective study is published in the March 12 issue of Archives of Internal Medicine.

The researchers used linked population-based administrative data for 391,139 patients who underwent operations in Ontario between April 1, 1997, and December 31, 2008. They identified residents 66 years of age and older who were dispensed an opioid within 7 days of one of these short-stay surgeries, and then assessed their long-term use, defined as a prescription for an opioid within 60 days of the 1-year anniversary of that surgery.

The investigators, led by Asim Alam, MD, from the University of Toronto in Ontario, identified a worrisome trend. The adjusted odds ratio of patients receiving an opioid prescription after surgery becoming long-term users was 1.44 (95% confidence interval [CI], 1.39 – 1.50).

Table 1. Opioid Prescriptions

Opioid Use Patients, n (%)
Within 7 days of discharge 27,636 (7.1)
At 1 year 30,145 (7.7)

 

Codeine was the most commonly prescribed opioid for patients who received an early prescription, followed by oxycodone. The researchers found an increase in oxycodone use from 5.4% within a week to 15.9% at a year.

“Not only did the prescriptions continue, but some patients went on to receive higher-potency drugs like oxycodone long term,” Dr. Bell said during an interview.

In a secondary analysis, the researchers evaluated the use of NSAIDs. They found patients receiving a prescription after surgery were also more likely to become long-term users. The adjusted odds ratio was 3.74 (95% CI, 3.27 – 4.28).

Table 2. NSAID Prescriptions

NSAID Use Patients, n (%)
Within 7 days of discharge 1169 (0.3)
At 1 year 30,080 (7.8)

 

“We thought that this article was a good reminder that initiation of short-term opioid therapy may lead to their longer-term use,” Mitchell Katz, MD, said in an editor’s note.

“We should be certain with any drug we prescribe that the benefits justify the risk. In the case of this study, it is unclear why 7% of elderly persons who were not previously taking opioids should have required them for minor operations known to cause little pain or why 8% of those who received an opioid for acute pain associated with minor surgery were still taking opioids 1 year later,” Dr. Katz noted. “We believe that when it comes to opioid administration for minor surgery, among older persons, less is more.”

In an accompanying commentary, Beth Darnall, PhD, and Brett Stacey, MD, from Oregon Health and Science University in Portland, pointed out that women are at greater risk for developing chronic pain conditions and experiencing greater pain intensity than men.

Women at Greater Risk

“Epidemiological studies of pharmacy claims in the United States show that opioids are more likely to be prescribed to women than men and that women are more likely to be taking higher doses of opioids,” they note.

Rates of toxic reactions have tripled among women since 1999 and hospitalizations for opioid-related poisoning have increased for women, but not for men, the authors report. “Examples of factors related to poisoning could include overprescription, overuse by the patient, adverse effects or toxic reactions related to drug-drug interactions.”

Before initiating opioid treatment for chronic pain, prescribers should fully assess the individual risks and benefits of the therapy and thoroughly discuss the goals, risks, and consequences of such therapy with each patient, Drs. Darnall and Stacey conclude.

In a second commentary, Mark Sullivan, MD, and Jane Ballantyne, MD, from the University of Washington School of Medicine in Seattle, point out the clinical experience from 20 years of “liberal opioid prescribing,” together with the findings of recent population-based studies, suggest that long-term opioid therapy may benefit patients with severe suffering that has been refractory to other medical and psychological treatments, but that is not often effective in achieving the goals originally envisaged, such as complete pain relief and functional restoration.

“This reframing of long term opioid therapy is a more honest appraisal of how it is actually used in practice,” they note. “It would allow better patient selection and help to avoid the disastrous effects of promising more of opioids than they can achieve.”

Many patients and prescribers embark on a course of opioid therapy with the hope that it will be short term owing to healing of the initial injury or disease, Drs. Sullivan and Ballantyne point out.

“Open-label follow-up studies of patients recruited into randomized controlled trials demonstrate that up to 60% of ‘ideal’ opioid candidates abandon opioid therapy within a few months either because of a lack of efficacy or because of adverse effects.”

This finding suggests that the patients who proceed to long-term therapy are a highly self-selected group and self-tapering is far less likely, they note. Of patients who receive daily opioid therapy for 90 days or more, two thirds are still taking opioids years later, they add. “This self-selected group is a high-risk group.”

This study was supported by the Institute for Clinical Evaluative Sciences, which is funded by the Ontario Ministry of Health and Long-Term Care. Dr. Bell receives support from a Canadian Institutes of Health Research and Canadian Patient Safety Institute chair in Patient Safety and Continuity of Care. Study coauthor Dr. Muhammad Mamdani serves on advisory boards for Hoffmann La Roche, GlaxoSmithKline, Pfizer, Novartis, Eli Lilly, Novo Nordisk, AstraZeneca, and Bristol-Myers Squibb. Dr. Sullivan has received educational grants from Pfizer and Covidien and has served as a consultant for Janssen. The other commentators have disclosed no relevant financial relationships.

Arch Intern Med. 2012;172:425-430. Abstract

STUDY HIGHLIGHTS

 

  • With use of administrative databases, the study was conducted in a population of 1.4 million in Ontario, Canada, for patients who underwent short-stay surgery between 1997 and 2008.
  • 2 separate cohorts were constructed for the use of opioids and NSAIDs.
  • Inclusion criteria were age 66 years and older, surgery performed in Ontario hospitals, discharge alive after short-stay surgery, and procedures associated with lower levels of postoperative pain.
  • Procedures yielding low pain levels were primarily ambulatory in nature.
  • Such procedures were cataract surgery, laparoscopic cholecystectomy, transurethral resection of the prostate, and varicose vein stripping.
  • Multiple administrative databases were used including the Ontario Drug Benefit Database, which recorded all prescriptions filled for those older than 65 years. Also, the Institute for Health Information Discharge Abstract Database captured all hospitalizations in Ontario, and the Registered Persons Database contained demographic information and vital statistics.
  • Excluded were individuals who received opioids within 1 year before the surgery, those admitted to the hospital for more than 3 days, those who had emergency procedures or who received palliative care, and those with other pain conditions.
  • For patients who underwent more than 1 procedure, only the first procedure was included for analysis.
  • The primary analysis examined prescription and use of opioids within 7 days of surgery with use of opioids during a maximum of 425 days after surgery.
  • The second analysis investigated the same association for NSAIDs.
  • Mean age of patients was 76 years, one third were men, and one quarter were admitted to a teaching-hospital setting.
  • Of 391,139 patients who were opioid naive at baseline and underwent short-stay surgery, 27,636 (7.1%) received a prescription for an opioid within 7 days of surgery.
  • By surgical indication, 18,231 (4.9%) of 371,438 patients received a prescription for cataract surgery, 7151 (65.3%) of 10,944 patients were prescribed opioids for laparoscopic cholecystectomy, 1211 (18.1%) of 6705 patients received opioids for transurethral resection of the prostate, and 1043 (50.8%) of 2052 patients were issued opioids for varicose vein stripping.
  • 30,145 patients (7.7%) received a prescription for opioids 1 year from surgery.
  • After multivariate adjustment, patients who received opioid prescriptions within 7 days of surgery were 44% more likely to become long-term opioid users vs those not receiving opioids within 7 days of surgery (OR, 1.44).
  • Among all patients who received an early opioid prescription, the most common opioid prescribed was codeine (93.4%) followed by oxycodone (5.4%).
  • At 1 year after surgery, codeine remained the most commonly prescribed opioid (87.5%), but more potent opioids were also prescribed in the long term, including transdermal fentanyl (1.6%) and oxycodone (15.9%).
  • Those who received a prescription for opioids early after surgery also had more prescriptions (3.3 vs 1.3), and mean days of supply of prescriptions was also higher (33.3 vs 7.5 days).
  • Among 383,780 patients who met criteria for NSAID prescription after short-stay surgery, 1169 (0.3%) were early users within 7 days of the surgery. Of these 1169 patients, 285 (24.4%) continued to receive NSAIDs at 1 year after surgery.
  • Roughly 29,795 (7.8%) of the 382,611 patients who were not prescribed an NSAID within 7 days of surgery received long-term NSAIDs.
  • In multivariate logistic regression analysis, the OR for long-term NSAID prescription use was 3.74 for those who received NSAIDs vs those who did not receive NSAIDs within 7 days of surgery.
  • The mean number of prescriptions in this group was higher (6.1 vs 1.8), and the number of days of medication supply 1 year after surgery was also higher (190 vs 46 days).
  • The authors concluded that prescriptions for opioid and NSAIDs after short-stay surgery in older persons was associated with an increased risk for long-term use of these agents.

 

CLINICAL IMPLICATIONS

 

  • Use of opioids within 7 days of short-stay surgery is associated with a higher likelihood of opioid use and use of more medications at 1 year after surgery among older persons.
  • Prescription for NSAIDs within 7 days of short-stay surgery is associated with an almost 4 times increased likelihood of NSAID use at 1 year after surgery in older persons.
Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s