Non-aspirin, non-steroidal anti-inflammatory drugs for osteoarthritis of the knee

WITHDRAWN: Celecoxib for rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a systemic auto-immune disorder, involving persistent joint inflammation. NSAIDs are used to control the symptoms of RA, but are associated with significant gastro-intestinal toxicity, including a risk of potentially life threatening gastroduodenal perforations, ulcers and bleeds. The NSAIDs known as the selective Cox II inhibitors, of which celecoxib is a member, were developed in order to reduce the GI toxicity, but are more expensive.

OBJECTIVES

To establish the efficacy and safety of celecoxib in the management of RA by systematic review of available evidence.

SEARCH METHODS

We searched the following databases up to August 2002: MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, National Research Register, NHS Economic Evaluation Database, Health Technology Assessment Database. The bibliographies of retrieved papers and content experts were consulted for additional references.

SELECTION CRITERIA

All eligible randomised controlled trials (RCTs) were included. No unpublished RCTs were included in this edition of the review.

DATA COLLECTION AND ANALYSIS

Data were abstracted independently by two reviewers. Data was analysed using a fixed effects model. A validated checklist was used to score the quality of the RCTs. The planned analysis was to pool, where appropriate continuous outcomes using mean differences and dichotomous outcomes using relative risk ratios. This was not however possible due to the lack of data.

MAIN RESULTS

Five RCTs were included (4465 participants); three of the studies also enrolled individuals with OA. The comparators were placebo, naproxen, diclofenac and ibuprofen. The evidence reviewed suggests that celecoxib controls the symptoms of RA to a similar degree to that of the active comparators examined (naproxen, diclofenac and ibuprofen). When compared to placebo, the percentage of patients showing improvement according to ACR 20 criteria at week 4 were 42/82 (51%) in the twice daily celecoxib 200mg group and 43/82 (52%) in the twice daily celecoxib 400mg group; these were significantly different from the placebo group in which 25/85 (29%) improved. The six month data reviewed support a reduced rate of UGI complications with celecoxib but there is also evidence to suggest that these benefits may not be evident in the long-term and that celecoxib offers no additional benefit in patients who are also receiving cardio-prophylactic low dose aspirin.

AUTHORS' CONCLUSIONS

For an individual with RA the potential benefits of celecoxib need to be balanced against the uncertainty that the short-term reduced incidence of upper GI complications are maintained in the long-term and its increased cost in comparison to traditional NSAIDs.

Towards a mechanism-based approach to pain management in osteoarthritis

Pain is the defining symptom of osteoarthritis (OA), yet available treatment options, of which NSAIDs are the most common, provide inadequate pain relief and are associated with serious health risks when used long term. Chronic pain pathways are subject to complex levels of control and modulation, both in the periphery and in the central nervous system. Ongoing clinical and basic research is uncovering how these pathways operate in OA. Indeed, clinical investigation into the types of pain associated with progressive OA, the presence of central sensitization, the correlation with structural changes in the joint, and the efficacy of novel analgesics affords new insights into the pathophysiology of OA pain. Moreover, studies in disease-specific animal models enable the unravelling of the cellular and molecular pathways involved. We expect that increased understanding of the mechanisms by which chronic OA-associated pain is generated and maintained will offer opportunities for targeting and improving the safety of analgesia. In addition, using clinical and genetic approaches, it might become possible to identify subsets of patients with pain of different pathophysiology, thus enabling a tailored approach to pain management.

Clinical pharmacology of analgesics assessed with human experimental pain models: bridging basic and clinical research

The medical impact of pain is such that much effort is being applied to develop novel analgesic drugs directed towards new targets and to investigate the analgesic efficacy of known drugs. Ongoing research requires cost-saving tools to translate basic science knowledge into clinically effective analgesic compounds. In this review we have re-examined the prediction of clinical analgesia by human experimental pain models as a basis for model selection in phase I studies. The overall prediction of analgesic efficacy or failure of a drug correlated well between experimental and clinical settings. However, correct model selection requires more detailed information about which model predicts a particular clinical pain condition. We hypothesized that if an analgesic drug was effective in an experimental pain model and also a specific clinical pain condition, then that model might be predictive for that particular condition and should be selected for development as an analgesic for that condition. The validity of the prediction increases with an increase in the numbers of analgesic drug classes for which this agreement was shown. From available evidence, only five clinical pain conditions were correctly predicted by seven different pain models for at least three different drugs. Most of these models combine a sensitization method. The analysis also identified several models with low impact with respect to their clinical translation. Thus, the presently identified agreements and non-agreements between analgesic effects on experimental and on clinical pain may serve as a solid basis to identify complex sets of human pain models that bridge basic science with clinical pain research.

An evidence-based update on nonsteroidal anti-inflammatory drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs), including both traditional nonselective NSAIDs and the selective cyclooxygenase (COX)-2 inhibitors, are widely used for their anti-inflammatory and analgesic effects. NSAIDs are a necessary choice in pain management because of the integrated role of the COX pathway in the generation of inflammation and in the biochemical recognition of pain. This group of drugs has recently come under scrutiny because of recent focus in the literature on the various adverse effects that can occur when applying NSAIDs. This review will provide an educational update on the current evidence of the efficacy and adverse effects of NSAIDs. It aims to answer the following questions: (1) are there clinically important differences in the efficacy and safety between the different NSAIDs, (2) if there are differences, which are the ones that are more effective and associated with fewer adverse effects, and (3) which are the effective therapeutic approaches that could reduce the adverse effects of NSAIDs. Finally, an algorithm is proposed which delineates a general decision-making tree to select the most appropriate analgesic for an individual patient based on the evidence reviewed.

TOIB Study. Are topical or oral ibuprofen equally effective for the treatment of chronic knee pain presenting in primary care: a randomised controlled trial with patient preference study. [ISRCTN79353052]

BACKGROUND

Many older people have chronic knee pain. Both topical and oral non- steroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat this. Oral NSAIDS are effective, at least in the short term, but can have severe adverse effects. Topical NSAIDs also appear to be effective, at least in the short term. One might expect topical NSAIDs both to be less effective and to have fewer adverse effects than oral NSAIDs. If topical NSAIDs have fewer adverse effects this may outweigh both the reduction in effectiveness and the higher cost of topical compared to oral treatment. Patient preferences may influence the comparative effectiveness of drugs delivered via different routes.

METHODS

TOIB is a randomised trial comparing topical and oral ibuprofen, with a parallel patient preference study. We are recruiting people aged 50 or over with chronic knee pain, from 27 MRC General Practice Research Framework practices across the UK. We are seeking to recruit 283 participants to the RCT and 379 to the PPS. Participants will be followed up for up to two years (with the majority reaching one year). Outcomes will be assessed by postal questionnaire, nurse examination, laboratory tests and medical record searches at one and two years or the end of the study.

DISCUSSION

This study will provide new evidence on the overall costs and benefits of treating chronic knee pain with either oral or topical ibuprofen. The use of a patient preference design is unusual, but will allow us to explore how preference influences response to a medication. In addition, it will provide more information on adverse events. This study will provide evidence to inform primary care practitioners, and possibly influence practice.

Treatment options for patients with osteoarthritis of the knee

Knee osteoarthritis (OA) affects many older people and may result in pain and loss of function in the knee. The article explores the wide spectrum of treatments available, including education, exercise, pharmacological agents and surgery. The evidence for these treatments is examined so that nurses have a knowledge base on which to build their practice. The importance of individual patient characteristics and available resources when deciding on treatment options is emphasized. The article is intended to be of use for both acute and primary care nurses who care for patients with knee OA.

Non-steroidal anti-inflammatory drugs, including cyclo-oxygenase-2 inhibitors, in osteoarthritic knee pain: meta-analysis of randomised placebo controlled trials

OBJECTIVE

To estimate the analgesic efficacy of non-steroidal anti-inflammatory drugs (NSAIDs), including selective cyclo-oxygenase-2 inhibitors (coxibs), in patients with osteoarthritis of the knee.

DESIGN

Systematic review and meta-analysis of randomised placebo controlled trials.

STUDIES REVIEWED

23 trials including 10 845 patients, median age of 62.5 years. 7807 patients received adequate doses of NSAIDs and 3038 received placebo. The mean weighted baseline pain score was 64.2 mm on 100 mm visual analogue scale (VAS), and average duration of symptoms was 8.2 years.

MAIN OUTCOME MEASURE

Change in overall intensity of pain.

RESULTS

Methodological quality of trials was acceptable, but 13 trials excluded patients before randomisation if they did not respond to NSAIDs. One trial provided long term data for pain that showed no significant effect of NSAIDs compared with placebo at one to four years. The pooled difference for pain on visual analogue scale in all included trials was 10.1 mm (95% confidence interval 7.4 to 12.8) or 15.6% better than placebo after 2-13 weeks. The results were heterogeneous, and the effect size for pain reduction was 0.32 (0.24 to 0.39) in a random effects model. In 10 trials that did not exclude non-responders to NSAID treatment the results were homogeneous, with an effect size for pain reduction of 0.23 (0.15 to 0.31).

CONCLUSION

NSAIDs can reduce short term pain in osteoarthritis of the knee slightly better than placebo, but the current analysis does not support long term use of NSAIDs for this condition. As serious adverse effects are associated with oral NSAIDs, only limited use can be recommended.

Time dependent risk of gastrointestinal complications induced by non-steroidal anti-inflammatory drug use: a consensus statement using a meta-analytic approach

OBJECTIVES

To provide an updated document assessing the global, NSAID-specific, and time dependent risk of gastrointestinal (GI) complications through meta-analyses of high quality studies.

METHODS

An exhaustive systematic search was performed. Inclusion criteria were: RCT or controlled study, duration of 5 days at least, inactive control, assessment of minor or major NSAID adverse effects, publication range January 1985 to January 2003. The publications retrieved were assessed during a specifically dedicated WHO meeting including leading experts in all related fields. Statistics were performed conservatively. Meta-regression was performed by regressing NSAID adjusted estimates against study duration categories.

RESULTS

Among RCT data, indolic derivates provided a significantly higher risk of GI complications related to NSAID use than for non-users: RR = 2.25 (1.00; 5.08) than did other compounds: naproxen: RR = 1.83 (1.25; 2.68); diclofenac: RR = 1.73 (1.21; 2.46); piroxicam: RR = 1.66 (1.14; 2.44); tenoxicam: RR = 1.43 (0.40; 5.14); meloxicam: RR = 1.24 (0.98; 1.56), and ibuprofen: RR = 1.19 (0.93; 1.54). Indometacin users had a maximum relative risk for complication at 14 days. The other compounds presented a better profile, with a maximum risk at 50 days. Significant additional risk factors included age, dose, and underlying disease. The controlled cohort studies provided higher estimates: RR = 2.22 (1.7; 2.9). Publication bias testing was significant, towards a selective publication of deleterious effects of NSAIDs from small sized studies.

CONCLUSION

This meta-analysis characterised the "compound" and "time" aspects of the GI toxicity of non-selective NSAIDs. The risk/benefit ratio of such compounds should thus be carefully and individually evaluated at the start of long term treatment.

Topical NSAIDs for acute pain: a meta-analysis

BACKGROUND

A previous systematic review reported that topical NSAIDs were effective in relieving pain in acute conditions like sprains and strains, with differences between individual drugs for efficacy. More trials, a better understanding of trial quality and bias, and a reclassification of certain drugs necessitate a new review.

METHODS

Studies were identified by searching electronic databases and writing to manufacturers. We selected randomised double blind trials comparing topical NSAID with either placebo or another active treatment in adults with acute pain, and extracted dichotomous information approximating to a 50% reduction in pain at one week, together with details of adverse events and withdrawals. Relative benefit and number-needed-to-treat (NNT), and relative risk and number-needed-to-harm (NNH) were calculated, with sensitivity analyses where appropriate to investigate differences between individual drugs and aspects of trial design.

RESULTS

Twenty-six double blind placebo controlled trials had information from 2,853 patients for evaluation of efficacy. Topical NSAID was significantly better than placebo in 19 of the 26 trials, with a pooled relative benefit of 1.6 (95% confidence interval 1.4 to 1.7), and NNT of 3.8 (95% confidence interval 3.4 to 4.4) compared with placebo for the outcome of half pain relief at seven days. Results were not affected by outcome reported, or condition treated, but smaller trials yielded a larger estimate of efficacy. Indirect comparisons of individual topical NSAIDs showed that ketoprofen was significantly better than all other topical NSAIDs, while indomethacin was barely distinguished from placebo. Three trials, with 433 patients, compared topical with oral NSAID (two trials compared the same drug, one compared different drugs) and found no difference in efficacy. Local adverse events, systemic adverse events, or withdrawals due to an adverse event were rare, and no different between topical NSAID and placebo.

CONCLUSIONS

Topical NSAIDs were effective and safe in treating acute painful conditions for one week.