Efficacy of non-steroidal anti-inflammatory drugs for low back pain: a systematic review of randomised clinical trials

Abstract

Purpose: To assess the efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) for low back pain.

Data sources: Computer aided search of published randomised clinical trials and assessment of the methods of the studies.

Study selection: 26 randomised clinical trials evaluating NSAIDs for low back pain were identified.

Data extraction: Score for quality (maximum = 100 points) of the methods based on four categories: study population; interventions; effect measurement; data presentation and analysis. Determination of success rate per study group and evaluation of different contrasts. Statistical pooling of placebo controlled trials in similar patient groups and using similar outcome measures.

Results: The methods scores of the trials ranged from 27 to 83 points. NSAIDs were compared with placebo treatment in 10 studies. The pooled odds ratio in four trials comparing NSAIDs with placebo after one week was 0.53 (95% confidence intervals 0.32 to 0.89) using the fixed effect model, indicating a significant effect in favour of NSAIDs compared with placebo. In nine studies NSAIDs were compared with other (drug) therapies. Of these, only two studies reported better results of NSAIDs compared with paracetamol with and without dextropropoxyphene. In the other trials NSAIDs were not better than the reference treatment. In 11 studies different NSAIDs were compared, of which seven studies reported no differences in effect.

Conclusions: There are flaws in the design of most studies. The pooled odds ratio must be interpreted with caution because the trials at issue, including the high quality trials, did not use identical outcome measures. The results of the 26 randomised trials that have been carried out to date, suggest that NSAIDs might be effective for short-term symptomatic relief in patients with uncomplicated low back pain, but are less effective or ineffective in patients with low back pain with sciatica and patients with sciatica with nerve root symptoms.

Figure 1

Pooled OR (Peto) in four placeo controlled trials evaluating NSAIDs for acute low back pain.