Ibuprofen 'barely better than placebo' at treating back pain

Friday February 3 2017

"Widely used anti-inflammatory drugs such as ibuprofen have little more benefit than a placebo when it comes to treating back pain," reports the Guardian.

This is based on a study looking at more than 6,000 people with back pain, comparing non-steroidal anti-inflammatory drugs (NSAIDs) with a placebo ("dummy" medicine).

While NSAIDs were found to reduce pain and make moving and doing daily activities easier, the difference compared to a placebo was not large enough for the researchers to consider it important. Also, people taking NSAIDs were at greater risk of gastrointestinal problems compared with those taking a placebo.

This was a good piece of research that looked at a number of high-quality studies to reach the conclusion that, generally-speaking, NSAIDs aren't that effective for back pain.

However, this research doesn't mean NSAIDs don't work at all for back pain and shouldn't be used. It's possible that some people will still benefit from them, with the study suggesting that around one in six people taking NSAIDs – rather than placebo – experience a significant reduction in pain.

Back pain usually gets better by itself after a few weeks but it might be a good idea to seek help if your pain is continuing for longer than this, is getting worse, or is stopping you doing your daily activities. Discuss the treatment options with your doctor.

NSAIDs are currently recommended by the National Institute for Health and Care Excellence (NICE) as a treatment option for lower back pain, alongside other approaches such as staying active, group exercise classes and manual therapy, such as chiropractic.

Where did the story come from?

The study was carried out by researchers from the University of Sydney in Australia and was funded by the Department of Education and Training of Australia, the National Health and Medical Research Council Australia and Sydney Medical School. The authors declare no conflict of interest.

The study was published in the peer-reviewed journal, Annals of the Rheumatic Diseases. The abstract is available to read for free.

The media reporting of the story was rather exaggerated and misleading, with the Mail Online claiming "ibuprofen doesn't work for back pain", when in fact the study found the NSAIDs are effective in reducing pain, just that the amount of benefit people feel is not thought to be a clinically important reduction compared to a placebo.

The Mail also claimed that "adults taking the cheap pills are actually three times more likely to suffer from stomach ulcers". In fact the study found NSAIDs increased the likelihood of any gastrointestinal problem, not necessarily ulcers, by 2.5 times.

What kind of research was this?

This was a systematic literature review and meta-analysis of 35 randomised controlled trials (RCTs) investigating the effects and safety of NSAIDs for spinal pain, compared with a placebo.

Current UK guidance indicates that NSAIDs such as ibuprofen and high-dose aspirincould be considered for managing back pain, whereas paracetamol alone should not be used.

RCTs are one of the best ways of looking at the effect of a treatment, in this case the effect of NSAIDs for treating back pain.

But while a systematic literature review is useful in bringing together evidence on a specific topic, it can only be as good as the studies included. Any shortfalls of the included studies will be brought forward into the review.

What did the research involve?

Researchers carried out a systematic review of RCTs comparing effectiveness and safety of NSAIDs with a placebo.

The review included 35 RCTs, involving 6,065 participants with acute or chronic neck or lower back pain. Any class, formulation or route of administration (topical, oral or injection) of NSAIDs was included as well as any dose and frequency of NSAIDs intake.

A follow-up period of less than two weeks was defined as immediate-term and a follow up of between two weeks and three months as short-term.

Pain outcome measures reported in the trials were either visual analogue scales or numerical rating scales. These were converted to a common scale that ranged from 0-100, with 0 meaning no pain or disability and 100 meaning the worst possible pain or disability.

A difference of 10 points on the 0-100 scale between placebo and drug was considered the smallest worthwhile effect that patients perceive as important. A 10-point difference was therefore the minimum needed to be considered "clinically important".

The number needed to treat (NTT) – the number of patients who need to be treated with an NSAID rather than a placebo for one additional person to benefit – was also calculated to give a more understandable measure of the benefit.

What were the basic results?

NSAIDs were mostly administered orally, but some trials injected the drugs or used a gel, patch or cream. When considering pain:

  • NSAIDs reduced pain and disability compared with the placebo in the immediate term (mean difference (MD) -9.2, 95% confidence interval [CI] -11.1 to -7.3).
  • NSAIDs reduced pain and disability compared with the placebo in the short-term (MD -7.7, 95% CI -11.4 to -4.1).

But neither of these results were clinically important according to the researchers as the difference between NSAIDs and placebo was less than their predefined threshold of 10 points on the 0-100 scale.

Taking into account what healthy people would consider an important reduction in pain, they calculated that six people (95% CI 4 to 10) would needed to be treated for two weeks with NSAIDs rather than placebo for one additional person to achieve clinically important pain reduction in the short-term.

When considering safety, a higher number of participants taking NSAIDs had gastrointestinal adverse reactions compared with placebo (relative risk [RR] 2.5, 95% CI 1.2 to 5.2). There was no difference between the NSAIDs group and placebo group in serious adverse events.

How did the researchers interpret the results?

The researchers conclude: "NSAIDs do not provide a clinically important effect on spinal pain, and six patients must be treated with NSAIDs for one patient to achieve a clinically important benefit in the short-term."

They add that "when this result is taken together with those from recent reviews on paracetamol and opioids, it is now clear that the three most widely used, and guideline-recommended medicines for spinal pain do not provide clinically important effects over placebo. There is an urgent need to develop new analgesics for spinal pain."

Conclusion

There was evidence that NSAIDs were effective in reducing pain and disability in patients with spinal pain, but treatment does not seem much more effective than a placebo and is not clinically important according to the researchers.

Moreover, for every six patients treated with NSAIDs rather than a placebo, only one additional patient would benefit in the short-term. People taking NSAIDs also have a higher risk of gastrointestinal adverse reactions. Patients might like to consider if this seems like a chance worth taking.

NSAIDs are currently recommended to treat back pain, but the authors suggest new, more effective drugs should be urgently developed.

The study does have some limitations:

  • The mode of treatment varied from oral intake to applying gel or cream. Some patients may feel better with a direct application compared to an oral drug, but it is difficult to say which is more effective as these were grouped together.
  • The dose also varied between studies and therefore it is difficult to know if NSAIDs were more effective at a higher dose.
  • The treatment period was on average only seven days and therefore it is hard to tell what long-term outcomes would have been if participants had continued to take NSAIDs.
  • The research focused on whether NSAIDs were effective for back pain as a whole, so it's difficult to know whether particular individuals or specific groups of patients might benefit from the treatment more than others.

This study was not set up to compare NSAIDs with other non-pharmacological treatments (such as exercise), some of which may be more effective than NSAIDs.

Analysis by Bazian
Edited by NHS Choices