April 11, 2017

Story by Rebecca Hood

The Paper of the Month for March comes from a team led by Roger Chou, M.D., professor of medicine, OHSU School of Medicine, and is entitled "Systemic Pharmacologic Therapies for Low Back Pain: A Systematic Review for an American College of Physicians Clinical Practice Guideline." OHSU contributors to this review, published in Annals of Internal Medicine, include Richard Deyo, M.D., Melissa Weimer, D.O., Rochelle Fu, Ph.D., Tracy Dana, M.L.S., Jessica Griffin, M.S., and Sara Grusing, B.A. The group also published an accompanying piece in the same issue entitled "Nonpharmacologic Therapies for Low Back Pain: A Systematic Review for an American College of Physicians Clinical Practice Guideline" to provide a comprehensive review of non-surgical low back pain therapies.

Low back pain is incredibly common in the clinic and has been estimated to cause more global disability than any other condition. A systematic review from the American College of Physicians and American Pain Society, also led by Dr. Chou, resulted in a guideline in 2007 supporting the use of acetaminophen and non-steroidal anti-inflammatory drugs (NSAIDs) as first-line pharmacologic options and skeletal muscle relaxants, benzodiazepines and antidepressants recommended as secondary options. This guideline has been widely endorsed and implemented. 

However, in the decade since that guideline was published, additional evidence and medications have become available, potentially necessitating an update of clinical practice guidelines. Therefore, Dr. Chou and his team undertook a systematic review of published studies to determine the most effective pharmacological therapy for low back pain.

After meticulously combing through databases for articles, trials and reviews, Dr. Chou and his team evaluated different medications or combinations of medications for outcomes including long- and short-term pain and function, mood, risk for surgery and harms. They extracted and synthesized results of these studies to come up with overarching conclusions about the treatment of lower back pain. According to Dr. Chou, "Our review provides a summary of currently available evidence to inform optimal management of low back pain."

"Regarding medications," said Dr. Chou, "an important finding  over the last several years was more evidence that opioids are associated with limited benefits, and more data regarding serious harms of opioids, in particular overdose and addiction." 

Contrary to the 2007 guidelines, which recommended acetaminophen, Dr. Chou explained, "A well-done trial found that acetaminophen was not effective for acute back pain." When it comes to newer drugs, Dr. Chou said, "Duloxetine, the first antidepressant in the serotonin-norepinephrine inhibitor class studied for low back pain, was found to be effective." The team also found that other drugs such as pregabalin and gabapentin were evaluated for low back pain, but "the studies don't clearly show effectiveness."

These findings are changing the way clinicians treat low back pain. "[The review] was used by the American College of Physicians to update its guideline," said Dr. Chou. "For medications, duloxetine is now another option for low back pain, the role of opioids is much more limited, and acetaminophen is no longer clearly a first-line treatment option for acute low back pain."

While this new findings and guideline are a step forward in the treatment of low back pain, there are still vast opportunities for improvements. "Unfortunately most treatments for LBP are associated with relatively small effects (e.g., 1 point or less on a 0 to 10 point pain scale)," explained Dr. Chou, "so there is still room for better treatment options." Because of shifts in the use of and policy related to opioids (including a 2016 CDC guideline with which Dr. Chou was involved), "We need more evidence to identify optimal alternatives to opioids as well as other treatment options," said Dr. Chou. And, in the context of the group's other article about non-pharmacological treatments for low back pain, "More research is needed to 'match' patients with the best treatment options." Although Dr. Chou has identified problems that must still be addressed, his team's findings and subsequent guidelines are already changing the way that low back pain is treated. 

Resources 

• Read the paper
  
• Recent OHSU published papers
  

Pictured above: Dr. Roger Chou