Opioid painkillers might temporarily ease the discomfort of arthritis, but they have no clear lasting benefit, a research review finds.

In an analysis of 23 clinical trials, researchers found, on average, opioid medications were somewhat effective at easing pain in patients with osteoarthritis. That is the common form of arthritis in which cartilage cushioning the joints gradually wears down, leading to swelling, stiffness and pain.

But the trials found no evidence that opioids improved patients' quality of life or helped with their depression. And any benefits for pain seemed to wane with time.

"We found that the magnitude of these effects is small and continues to decrease over time," said lead researcher Dr. Raveendhara Bannuru. He is director of the Center for Treatment Comparison and Integrative Analysis at Tufts Medical Center, in Boston.

Treatment guidelines for chronic pain, other than cancer-related pain, already say opioids should be a last resort.

With osteoarthritis, Bannuru said, the drugs are only recommended if a patient has not gotten relief from other medical therapies, and if surgery – like knee or hip replacement – is not an option.

Instead, patients should try to exercise regularly and maintain a healthy lifestyle. As for medications, Bannuru said, topical versions of nonsteroidal anti-inflammatory drugs (NSAIDs) – like ibuprofen and naproxen – are a "first choice."

These creams or ointments help people avoid the side effects that can come with prolonged used of oral NSAIDs (such as Motrin, Advil, Aleve), Bannuru noted. Injections of hyaluronic acid, a substance in joint fluids, are another option, he said.

In addition, aerobic activity, like walking, and exercises that strengthen the muscles around the arthritic joint can be helpful, according to Dr. Steven Eyanson, a rheumatologist who was not involved in the study.

And if a patient is overweight, shedding some pounds can help ease pain and improve joint function, said Eyanson, a retired adjunct assistant professor at the University of Iowa in Iowa City.

"In the case of osteoarthritis, the benefits of therapy by opioid pain relief are very limited," Eyanson said.

Bannuru was scheduled to present the findings Saturday at the American College of Rheumatology's annual meeting, in Atlanta. Research presented meetings is generally considered preliminary until it is published in a peer-reviewed journal.

For the study, the researchers pooled the results of 23 previously published clinical trials that involved more than 11,400 osteoarthritis patients.

Overall, the investigators found, opioid treatment had a modest effect on people's pain over two to 12 weeks. At higher doses, the drugs were actually less effective, and carried a higher risk of side effects, such as nausea, constipation and diarrhea.

"In light of dependency concerns and the discomfort that many patients feel while taking the drugs, it would appear that there is no optimal therapeutic window for the use of oral opioids in osteoarthritis," Bannuru said.

The results come during a national crisis of opioid addiction that, according to government figures, is killing 130 Americans each day.

After years of skyrocketing, prescriptions for opioids – like OxyContin, Vicodin and Percocet – have been declining since 2012, according to the U.S. Centers for Disease Control and Prevention. In recent years, illegal opioids – like heroin and illicitly manufactured fentanyl – have become the biggest concern.

Still, prescription opioids were involved in 36% of opioid overdose deaths in 2017, the CDC says.

"We hope the results of our study will empower osteoarthritis patients to have informed discussions with their health care providers about the safest and most effective treatment options for their pain," Bannuru said.

Eyanson said that, to him, "the take-home messages are that opioids have limited benefit in osteoarthritis pain control, and have significant potential for risk."

Most osteoarthritis patients will benefit from a "more holistic approach" – including medication and non-drug therapies, and in some cases, surgery, he added.