Abstract
Introduction
NSAIDs are widely used. Almost 10% of people in The Netherlands used a non-aspirin NSAID in 1987, and the overall use was 11 defined daily doses per 1000 population per day. In Australia in 1994, overall use was 35 defined daily doses per 1000 population a day, with 36% of the people receiving NSAIDs for osteoarthritis, 42% for sprain and strain or low back pain, and 4% for rheumatoid arthritis; 35% of the people receiving NSAIDs were aged >60 years.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical questions: Are there any important differences between NSAIDs? What are the effects of topical NSAIDs; and of co-treatments to reduce the risk of gastrointestinal adverse effects of NSAIDs? We searched: Medline, Embase, The Cochrane Library, and other important databases up to September 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
Results
We found 36 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
Conclusions
In this systematic review we present information relating to the benefits and harms of the following interventions: alternative analgesics, H2 blockers, misoprostol, NSAIDs (systemic, topical, differences in efficacy between, dose-response relationship of), proton pump inhibitors.
Key Points
Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit the cyclo-oxygenase (COX) enzyme to exert their anti-inflammatory, analgesic, and antipyretic effects.
No important differences in efficacy have been demonstrated between different systemic NSAIDs in the management of musculoskeletal disorders.
There seems to be a plateau for effectiveness, with recommended doses close to those required for maximal effectiveness. However, the risk of adverse effects increases with increasing dose, with no plateau.
Systemic NSAIDs that selectively inhibit COX-2 have a reduced risk of causing gastrointestinal ulcers compared with less-selective NSAIDs. However, COX-2 inhibitors increase the risk of myocardial infarction and other cardiovascular events.
Paracetamol is less effective than systemic NSAIDs at reducing pain in osteoarthritis, but similarly effective for acute musculoskeletal pain.
Misoprostol reduces serious NSAID-related gastrointestinal complications and symptomatic ulcers compared with placebo, but is itself associated with adverse effects including diarrhoea, abdominal pain, and nausea.
Proton pump inhibitors and H2 antagonists have been shown to reduce endoscopic ulcers in people taking NSAIDs, but their clinical benefits are less clear.
We don't know which treatment is the most effective at reducing gastrointestinal adverse effects from systemic NSAIDs.
We don't know whether topical NSAIDs are beneficial.
About this condition
Definition
Non-steroidal anti-inflammatory drugs (NSAIDs) have anti-inflammatory, analgesic, and antipyretic effects, and they inhibit platelet aggregation. This review deals specifically with the use of NSAIDs for the treatment of the symptoms of musculoskeletal conditions. NSAIDs have no documented effect on the course of musculoskeletal diseases. NSAIDs inhibit the enzyme cyclo-oxygenase (COX), which has two known isoforms: COX-1 and COX-2. NSAIDs are often categorised according to their ability to inhibit the individual isoforms, with newer NSAIDs often predominantly inhibiting the COX-2 isoform and older NSAIDs often being less specific inhibitors.
Incidence/ Prevalence
NSAIDs are widely used. Almost 10% of people in The Netherlands used a non-aspirin NSAID in 1987, and the overall use was 11 defined daily doses per 1000 population per day. In Australia in 1994, overall use was 35 defined daily doses per 1000 population a day, with 36% of the people receiving NSAIDs for osteoarthritis, 42% for sprain and strain or low back pain, and 4% for rheumatoid arthritis; 35% of the people receiving NSAIDs were aged >60 years.
Aims of intervention
To reduce symptoms in rheumatic disorders; to avoid severe gastrointestinal adverse effects.
Outcomes
Primary outcomes: pain intensity; personal preference for one drug over another; global efficacy; clinically significant gastrointestinal complications. Secondary outcomes: number of tender joints; perforation; gastrointestinal haemorrhage; dyspepsia; and ulcer detected by routine endoscopy; other adverse effects.
Methods
Clinical Evidence search and appraisal September 2009. The following databases were used to identify studies for this systematic review: Medline 1966 to September 2009, Embase 1980 to September 2009, and The Cochrane Database of Systematic Reviews 2009, Issue 3 (1966 to date of issue). An additional search within the Cochrane Library was carried out for the Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment (HTA). We also searched for retractions of studies included in the review. Abstracts of the studies retrieved from the initial search were assessed by an information specialist. Selected studies were then sent to the contributor for additional assessment, using pre-determined criteria to identify relevant studies. Study design criteria for inclusion in this review were: published systematic reviews of RCTs. We included systematic reviews of RCTs where harms of an included intervention were studied applying the same study design criteria for inclusion as we did for benefits. For comparisons between paracetamol and an NSAID for musculoskeletal disorders, we included individual RCTs, as very few trials have been published. This review focuses on the use of NSAIDs for the treatment of the symptoms of musculoskeletal disorders. We have presented data regarding our primary outcomes in preference to data on secondary outcomes where available. More than 100 systematic reviews and thousands of RCTs have compared various NSAIDs. Owing to the large volume of data, in the question on different systemic NSAIDs compared with each other, we assess NSAIDs for the indication of rheumatoid arthritis only as results in this population are generalisable to other musculoskeletal conditions. We assess the use of topical NSAIDs for any musculoskeletal condition. We have not included any systematic reviews that assess single NSAIDs — again, owing to the larger volume of data. We have included systematic reviews and RCTs of the harms of NSAIDs (e.g., gastrointestinal toxicity) not solely in people with musculoskeletal disorders if the evidence would otherwise have been insufficient. Many RCTs are unpublished or published in sources not indexed in publicly available databases. The quality of the RCTs is variable and bias is common, both in the design and analysis of the RCTs, to such an extent that one systematic review identified false significant findings favouring new drugs over control drugs in 6% of RCTs. We have favoured systematic reviews that have not been sponsored or authored by the pharmaceutical industry, because bias in such reviews has repeatedly been shown but may be difficult to detect. For example, it is easy seemingly to follow the rules for systematic reviews and yet use inclusion and exclusion criteria that omit inconvenient studies. Furthermore, one systematic review found that industry-supported meta-analyses of drugs are of lower methodological quality, pay less attention to bias, and have fewer reservations than Cochrane reviews of the same drugs.We have also favoured higher-quality reviews, based on search rigour and appropriate meta-analysis, over poorer-quality reviews with more-recent search dates. In addition, we use a regular surveillance protocol to capture harms alerts from organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA), which are added to the review as required. To aid readability of the numerical data in our reviews, we round many percentages to the nearest whole number. Readers should be aware of this when relating percentages to summary statistics such as relative risks (RRs) and odds ratios (ORs). We have performed a GRADE evaluation of the quality of evidence for interventions included in this review (see table ). The categorisation of the quality of the evidence (into high, moderate, low, or very low) reflects the quality of evidence available for our chosen outcomes in our defined populations of interest. These categorisations are not necessarily a reflection of the overall methodological quality of any individual study, because the Clinical Evidence population and outcome of choice may represent only a small subset of the total outcomes reported, and population included, in any individual trial. For further details of how we perform the GRADE evaluation and the scoring system we use, please see our website (www.clinicalevidence.com). We believe that we have presented sufficient data to answer the question on the efficacy and safety of NSAIDs (both oral and topical) and that reporting further confirmatory data is not beneficial to our readers. We will continue to scan the literature, including drug safety monitoring, and will update the text of this review only should any high-quality evidence be published that reflects a change to the evidence we currently present.
Table.
GRADE evaluation of NSAIDs.
Important outcomes | Pain intensity, global efficacy, gastrointestinal adverse effects | ||||||||
Number of studies (participants) | Outcome | Comparison | Type of evidence | Quality | Consistency | Directness | Effect size | GRADE | Comment |
Are there any important differences between systemic NSAIDs? | |||||||||
4 (10,408) | Pain intensity | COX-2 inhibitors v older systemic NSAIDs | 4 | 0 | 0 | 0 | 0 | High | |
244 (at least 38,465 people) | Pain intensity | Different systemic NSAIDs v each other | 4 | 0 | 0 | 0 | 0 | High | |
2 (560) | Pain intensity | Systemic NSAIDs v paracetamol | 4 | 0 | 0 | 0 | 0 | High | |
68 (53,742) | Symptomatic ulcers | COX-2 inhibitors v older NSAIDs | 4 | 0 | 0 | 0 | +1 | High | Effect-size point added for RR <0.5 |
24 (38,053) | Cardiovascular events | COX-2 inhibitor v older NSAIDs | 4 | 0 | 0 | 0 | 0 | High | |
At least 115 RCTs, at least 1545 people | Pain intensity | High-dose v lower-dose systemic NSAIDs | 4 | 0 | 0 | 0 | 0 | High | |
4 reviews (at least 1545 people) | Adverse effects | High-dose v lower-dose systemic NSAIDs | 4 | 0 | 0 | 0 | 0 | High | |
What are the effects of co-treatments to reduce the risk of gastrointestinal adverse effects of systemic NSAIDs? | |||||||||
10 (11,507) | Serious gastrointestinal events | Misoprostol v placebo | 4 | 0 | 0 | 0 | 0 | High | |
2 (1472) | Gastrointestinal ulcers, erosions, or dyspepsia | Misoprostol v proton pump inhibitor | 4 | –1 | 0 | 0 | 0 | Moderate | Quality point deducted for clinically irrelevant definition of ulcers |
15 (2621) | Gastrointestinal complications | H2 blockers v placebo | 4 | –1 | 0 | 0 | 0 | Moderate | Quality point deducted for clinically irrelevant definition of ulcers |
1 (541) | Gastrointestinal erosions, ulcers, dyspepsia | H2 blockers v proton pump inhibitors | 4 | –1 | 0 | 0 | 0 | Moderate | Quality point deducted for clinically irrelevant definition of ulcers |
6 (1358) | Serious gastrointestinal complications | Proton pump inhibitors v placebo | 4 | –1 | 0 | 0 | 0 | Moderate | Quality point deducted for clinically irrelevant definition of ulcers |
What are the effects of topical NSAIDs? | |||||||||
26 (2853) | Pain intensity | Topical NSAIDs v placebo for any acute musculoskeletal pain | 4 | –1 | 0 | –2 | 0 | Very low | Consistency point deducted for extreme heterogeneity of trials analysed. Directness points deducted for unclear outcome measure and very short-term follow-up |
8 (1141) | Pain intensity | Topical NSAIDs v placebo for osteoarthritis | 4 | –1 | –1 | –1 | 0 | Very low | Quality point deducted for methodological problems with some studies. Consistency point deducted for heterogeneity of trials in meta-analyses. Directness point deducted for no long-term outcome data |
5 (962) | Pain intensity | Topical NSAID v oral NSAID | 4 | –1 | –1 | –1 | 0 | Very low | Quality point deducted for poor-quality RCTs included. Consistency point deducted deducted for heterogeneity of trials in meta-analyses. Directness point deducted for no long-term outcome data |
Type of evidence: 4 = RCT; 2 = Observational; 1 = Non-analytical/expert opinion. Consistency: similarity of results across studies. Directness: generalisability of population or outcomes.
Glossary
- Defined daily dose
The assumed average daily dose for the main indication of a specified drug. The defined daily dose per 1000 population a day is an estimate of the proportion of that population receiving treatment with that drug.
- High-quality evidence
Further research is very unlikely to change our confidence in the estimate of effect.
- Moderate-quality evidence
Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
- Very low-quality evidence
Any estimate of effect is very uncertain.
Disclaimer
The information contained in this publication is intended for medical professionals. Categories presented in Clinical Evidence indicate a judgement about the strength of the evidence available to our contributors prior to publication and the relevant importance of benefit and harms. We rely on our contributors to confirm the accuracy of the information presented and to adhere to describe accepted practices. Readers should be aware that professionals in the field may have different opinions. Because of this and regular advances in medical research we strongly recommend that readers' independently verify specified treatments and drugs including manufacturers' guidance. Also, the categories do not indicate whether a particular treatment is generally appropriate or whether it is suitable for a particular individual. Ultimately it is the readers' responsibility to make their own professional judgements, so to appropriately advise and treat their patients.To the fullest extent permitted by law, BMJ Publishing Group Limited and its editors are not responsible for any losses, injury or damage caused to any person or property (including under contract, by negligence, products liability or otherwise) whether they be direct or indirect, special, incidental or consequential, resulting from the application of the information in this publication.
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