Opioids Effective for Many Acute Pain Conditions

By Pat Anson

As pharmaceutical companies scramble to develop new non-opioid treatments for pain, a large new review found that opioid analgesics are effective for many acute pain conditions and come with little risk.

Led by researchers at the University of Sydney, the study looked at 59 clinical studies for dozens of short-term acute pain conditions.

They found “high-certainty” evidence that opioids were effective in treating abdominal pain, postpartum pain and dental pain; “moderate-certainty” evidence that they relieve pain from sciatica, post-operative pain and ten other acute conditions; and “low-certainty” evidence that they work on nine other short-term pain conditions.

There was no high quality evidence that opioids are ineffective for acute pain, but there was moderate and low quality evidence that they provide little relief for some acute conditions, such as pain from minimally invasive surgeries.

Adverse events were limited to vomiting and nausea, with no serious events like overdose, death, or addiction reported in any of the 59 studies.

“This paper is best understood as a broad evidence map, not a simple yes/no verdict on opioids for acute pain. It shows that opioids have helped in some acute pain conditions, but benefits are mixed, often modest, and vary by condition and timepoint,” said Lynn Webster, MD, a pain management expert and Senior Fellow at the Center for U.S. Policy, who was not involved in the study.

“The authors did not find a significant increase in serious adverse events in these short-term trials, but they also emphasize that harms reporting was incomplete.”

In short, opioids work for many acute pain conditions, depending on the dose, and pose no serious risk of harm, at least over the short-term.

“There was no high certainty evidence showing that opioids were not efficacious,” researchers reported in the journal Drugs. “There was no significant increased risk of serious adverse events in any review.”  

‘Opioids Aren’t Effective’ 

But that is not how the study was portrayed in a University of Sydney press release, which warned in a headline that “opioids aren’t effective for many acute pain conditions.”

The release quoted one author as saying opioids work “only slightly better than a placebo” and are not worth the risk.

“Our review found that they did not provide large or lasting pain relief compared with placebo for the vast majority of acute pain conditions, with pain relief typically lasting only a few hours,” said lead author Christina Abdel Shaheed, PhD, an Associate Professor in the School of Public Health at the University of Sydney. 

“By showing that the benefits are generally small, short-lived, absent for many common conditions, and sometimes harmful, our research challenges the widely held belief that opioids are the most effective ‘go-to’ option for acute pain.”

Shaheed and several of her co-authors have participated in other studies that take a dim view of opioids. One is a controversial 2023 trial, known as the OPAL study, which found that low doses of oxycodone work no better than a placebo in relieving acute back or neck pain. 

“Opioids should not be recommended for acute back and neck pain, full stop,” said Christine Lin, PhD. a Professor of Public Health at the University of Sydney, who was the lead investigator of the OPAL study and a co-author of the new study. 

Critics complained the OPAL study’s conclusions were too broad, not supported by evidence, and “misplaced and dangerous.”  In reply, Lin agreed that they may have gone too far and that their findings “might not be generalizable to all patients.”

Dr. Webster takes a similar view of the new study, saying it would be wrong to draw conclusions about the effectiveness or harm caused by opioids, given the low quality of most studies that were reviewed.

“The paper is best viewed as a map of evidence gaps and variable-quality evidence, not a final word,” Webster told PNN. “Most of the underlying reviews were rated critically low quality, so the paper is very useful for mapping what we know and what we still don’t know. Broad conclusions about opioid efficacy would be inappropriate.” 

One of the co-authors of the new study is Jane Ballantyne, MD, a former President and current Vice-President of Physicians for Responsible Opioid Prescribing (PROP), an anti-opioid activist group. Ballantyne reported no conflicts of interest, although in the past she has acknowledged serving as a paid expert witness in opioid litigation cases.

CDC Study Finds ‘No Significant Change’ in Use of Rx Opioids

By Pat Anson, PNN Editor

A new study by CDC researchers has a surprise finding, concluding that there has been “no significant change in the use of prescription opioids” over the past decade by U.S. adults.

The study is based on the National Health and Nutrition Examination Survey, in which a nationally representative sample of nearly 20,000 adults is asked every two years about their healthcare and nutrition.

Although the number of opioid prescriptions in the U.S. has dropped 43% since their peak in 2011, the survey found that the use of opioid medication hasn’t changed much at all.  

In 2017–2018, the survey found that 5.7% of U.S. adults used one or more prescription opioids in the past 30 days, compared to 6.2% of adults a decade earlier.

“Between 2009–2010 and 2017–2018, no significant trend in the use of prescription opioids was observed; however, an increasing trend in the use of nonopioid prescription pain medications without prescription opioids was seen,” researchers found.

USE OF PRESCRIPTION PAIN MEDICATIONS BY U.S. ADULTS

SOURCE: CDC

In 2017-2018, women (6.4%) were more likely to be prescribed opioids than men (4.9%). The use of opioids increased with age, from 2.8% among young adults aged 20–39 to 8.2% for those aged 60 and over.

The use of opioid prescriptions was highest among whites (6.4%), followed by blacks (5.2%), Hispanics (3.4%) and Asian adults (1.4%).

The survey did not ask respondents about the dose of opioids they were prescribed, which may account for the discrepancy with other prescription drug databases.    

A 2018 study by the health analytics firm IQVIA found a significant decline in the number of high dose opioid prescriptions of 90 MME (morphine milligram equivalent) or more. But low dose prescriptions of 20 MME or less remained relatively stable.

While the percentage of Americans using opioid prescriptions has remained relatively flat over the past decade, according to the survey, there was a notable increase in the use of non-opioid prescription pain relievers, which rose from 4.3% in 2009-2010 to 5.7% in 2017-2018.

Migraine drugs, COX-2 inhibitors, and non-steroidal anti-inflammatory drugs (NSAIDs) were classified in the survey as non-opioid prescription pain relievers, but anti-depressants and anti-convulsants were not – even though they are increasingly used to treat pain. The IQVIA study found 67 million prescriptions for the anti-convulsant medication gabapentin (Neurontin) in 2018 — a fact that is not reflected in the CDC findings.

The CDC is currently preparing an update of its controversial 2016 opioid guideline, which has been widely adopted as policy by other federal agencies, states, insurers, pharmacies and many doctors — who have used it as an excuse to take people off opioids or greatly reduce their doses.

The updated guideline – which is expected in late 2021 -- is likely to expand the CDC’s recommendations to include the use of opioids for treating short-term acute pain.

Study Finds Limited Evidence to Support Use of Non-Opioid Drugs for Chronic Pain

By Pat Anson, PNN Editor

A new study by federal researchers has found limited evidence to support the use of non-opioid medications in treating chronic pain conditions such as fibromyalgia, neuropathy, rheumatoid arthritis and low back pain.

Only small improvements in pain and function were found in the use of anti-convulsants and non-steroidal anti-inflammatory drugs (NSAIDs), while moderate improvement was found in the use of some antidepressants.

Researchers noted that evidence was “too limited to draw conclusions” on long-term use of non-opioid drugs, and “no treatment achieved a large improvement in pain or function.” They also cautioned that “careful consideration of patient characteristics is needed in selecting nonopioid drug treatments” because of the risk of side effects.

The report was prepared for the Agency for Healthcare Research and Quality (AHRQ) by the Pacific Northwest Evidence-based Practice Center (EPC) at Oregon Health & Science University. The EPC has recently finalized two other studies on the use of opioids and nonpharmacological treatments for chronic pain.

Unlike their report on opioids, EPC researchers did not consult with technical experts and peer reviewers associated with Physicians for Responsible Opioid Prescribing (PROP), an anti-opioid activist group.

The researchers analyzed nearly 200 clinical studies and systematic reviews of non-opioid medication. Only 25 of the studies were rated as good quality and only 8 lasted a year or more. The pharamceutical industry funded 82 percent of them.

The EPC report is more cautious than other federal studies on the use of non-opioids such as pregabalin (Lyrica) and gabapentin (Neurontin).  Side effects from those drugs were often so severe that some patients stopped taking them and dropped out of clinical studies.

“Large increases in risk of adverse events were seen with pregabalin (blurred vision, cognitive effects, dizziness, peripheral edema, sedation, and weight gain), gabapentin (blurred vision, cognitive effects, sedation, weight gain), and cannabis (nausea, dizziness),” EPC researchers found. “Dose reductions reduced the risk of some adverse events with SNRI antidepressants. In the short term small increases in risk of major coronary events and moderate increases in serious gastrointestinal events (both short and long term) were found with NSAIDs.”

The EPC study is in marked contrast to the 2016 CDC opioid guideline, which recommends pregabalin, gabapentin and NSAIDs as alternatives to opioids with little to no mention of their side effects.

Other researchers have also warned that the effectiveness of gabapentin and pregabalin, which belong to a class of anti-convulsant drugs known as gabapentinoids, is often exaggerated in prescribing guidelines.

“Gabapentinoids have become frequent first-line alternatives in patients with chronic pain from whom opioids are being withheld or withdrawn, as well as in patients with acute pain who traditionally received short courses of low-dose opioid,” researchers at the University of South Carolina School of Medicine warned in a 2019 study.

“The evidence to support off-label gabapentinoid use for most painful clinical conditions is limited. For some conditions, no well-performed controlled trials exist.”

The EPC’s trio of studies on opioids, non-opioid drugs and non-pharmacological treatments are expected to help guide the CDC as it prepares an update and expansion of its 2016 opioid guideline, which is expected in late 2021. The update is likely to include new guidelines for treating short term, acute pain.  

How will CDC interpret the EPC findings on opioids and non-opioids? One outcome is suggested in the opioid study.

“Findings support the recommendation in the 2016 CDC guideline that opioids are not first-line therapy and to preferentially use nonopioid alternatives,” researchers said.