Non-steroidal anti-inflammatory drugs for acute low back pain

Background Acute low back pain (LBP) is a common health problem. Non-steroidal anti-inflammatory drugs (NSAIDs) are oIen used in the treatment of LBP, particularly in people with acute LBP. In 2008, a Cochrane Review was published about the eFicacy of NSAIDs for LBP (acute, chronic, and sciatica), identifying a small but significant eFect in favour of NSAIDs compared to placebo for short-term pain reduction and global improvement in participants with acute LBP. This is an update of the previous review, focusing on acute LBP. Objectives To assess the eFects of NSAIDs compared to placebo and other comparison treatments for acute LBP. Search methods We searched CENTRAL, MEDLINE, Embase, PubMed, and two trials registers for randomised controlled trials (RCT) to 7 January 2020. We also screened the reference lists from relevant reviews and included studies. Selection criteria We included RCTs that assessed the use of one or more types of NSAIDs compared to placebo (the main comparison) or alternative treatments for acute LBPin adults (≥ 18 years); conductedinbothprimary andsecondary care settings.We assessedthe eFects oftreatment on pain reduction, disability, global improvement, adverse events, and return to work. Data collection and analysis Two review authors independently selected trials to be included in this review, evaluated the risk of bias, and extracted the data. If appropriate, we performed a meta-analysis, using a random-eFects model throughout, due to expected variability between studies. We assessedthequality ofthe evidenceusing theGRADE approach.Weusedstandardmethodologicalprocedures recommendedbyCochrane. Main results We included 32 trials, with a total of 5356 participants (age range 16 to 78 years). Follow-up ranged from one day to six months. Studies were conducted across the globe, the majority taking place in Europe and North-America. Africa and the Eastern Mediterranean region were not represented. We considered seven studies at low risk of bias. Performance and attrition were the most common biases. There was oIen a lack of information on randomisation procedures and allocation concealment (selection bias); studies were prone to selective reporting bias, since most studies did not register their trials. Almost half of the studies were industry-funded. There is moderate quality evidence that NSAIDs are slightly more eFective in short-term (≤ 3 weeks) reduction of pain intensity (visual analogue scale (VAS), 0 to 100) than placebo (mean diFerence (MD) -7.29 (95% confidence interval (CI) -10.98 to -3.61; 4 RCTs, N = 815). There is high quality evidence that NSAIDs are slightly more eFective for short-term improvement in disability (Roland Morris Disability Questionnaire (RMDQ), 0 to 24) than placebo (MD -2.02, 95% CI -2.89 to -1.15; 2 RCTs, N = 471). The magnitude of these eFects is small and probably not clinically relevant. There is low quality evidence that NSAIDs are slightly more eFective for short-term global improvement than placebo (risk ratio (RR) 1.40, 95% CI 1.12 to 1.75; 5 RCTs, N = 1201), but there was substantial heterogeneity (I2 52%) between studies. There is very low quality evidence of no clear diFerence in the proportion of participants experiencing adverse events when using NSAIDs compared to placebo (RR 0.86, 95% CI 0.63 to 1.18; 6 RCTs, N = 1394). There is very low quality evidence of no clear diFerence between the proportion of participants who could return to work aIer seven days between those who used NSAIDs and those who used placebo (RR 1.48, 95% CI 0.98 to 2.23; 1 RCT, N = 266). There is low quality evidence of no clear diFerence in short-term reduction of pain intensity between those who took selective COX-2 inhibitor NSAIDs compared to non-selective NSAIDs (mean change from baseline -2.60, 95% CI -9.23 to 4.03; 2 RCTs, N = 437). There is moderate quality evidence of conflicting results for short-term disability improvement between groups (2 RCTs, N = 437). Low quality evidence from one trial (N = 333) reported no clear diFerence between groups in the proportion of participants experiencing global improvement. There is very low quality evidence of no clear diFerence in the proportion of participants experiencing adverse events between those who took COX-2 inhibitors and non-selective NSAIDs (RR 0.97, 95% CI 0.63 to 1.50; 2 RCTs, N = 444). No data were reported for return to work. Authors' conclusions This updated Cochrane Review included 32 trials to evaluate the eFicacy of NSAIDs in people with acute LBP. The quality of the evidence ranged from high to very low, thus furtherresearch is (very) likely to have an important impact on our confidence in the estimates of eFect, and may change the estimates. NSAIDs seemed slightly more eFective than placebo for short-term pain reduction (moderate certainty), disability (high certainty), and global improvement (low certainty), but the magnitude of the eFects is small and probably not clinically relevant. There was no clear diFerence in short-term pain reduction (low certainty) when comparing selective COX-2 inhibitors to non-selective NSAIDs. We found very low evidence of no clear diFerence in the proportion of participants experiencing adverse events in both the comparison of NSAIDs versus placebo and selective COX-2 inhibitors versus non-selective NSAIDs. We were unable to draw conclusions about adverse events and the safety of NSAIDs for longer-term use, since we only included RCTs with a primary focus on short-term use of NSAIDs and a short follow-up. These are not optimal for answering questions about longer-term or rare adverse events

• View at Publisher