The short-term effectiveness of pharmacotherapeutic interventions for knee osteoarthritis

Study Type: Meta analysis
OE Level of Evidence: 2
Journal Level of Evidence: N/A
63 randomised placebo-controlled trials were included in this meta-analysis to determine the maximal short-term effect of common pharmacotherapeutic interventions for short-term pain relief for knee osteoarthritis. Opioid therapy, oral NSAID, topical NSAID, steroid injections, paracetamol, glucosamine sulphate, and chondroitin sulphate were evaluated in this study. When assessed in Please login to view the rest of this report. Please login to view the rest of this report.
Funding: Non-Industry funded
Sponsor: Norwegian Research Council
Conflicts: None disclosed
Why was this study needed now?
Osteoarthritis is the most common source of pain and disability among adults. There are a number of pharmacotherapeutic interventions currently employed for the management of this condition; however, little is known regarding the profile of their effectiveness over time when compared to a placebo. Additionally, many of the previous studies that have evaluated these treatments have failed to reference results to a patient-centered threshold of effectiveness to guide physicians when making clinical decisions.
What was the principal research question?
At what time point is the pain relief provided by pharmacotherapeutic interventions for knee osteoarthritis the greatest? What is the effect size of pharmacotherapeutic interventions compared to placebo? When compared to placebo, what is the pain-relieving efficacy of pharmacotherapeutic interventions when using patient-centered outcome thresholds?
Data Source: Medline, EMBASE, PEDro, and the Cochrane Central Register of Controlled Trials were searched for relevant articles published up to November 2005. Additionally, the reference lists of systematic reviews were cross-referenced, conference abstracts were screened, and experts in the field were consulted.
Index Terms: Index terms searched were: knee, osteoarthritis, randomized, controlled, placebo, NSAID, coxib, COX-2 inhibitor.
Study Selection: Eligibility criteria included: 1) diagnosis knee osteoarthritis clinically using American College of Rheumatology criteria or on radiograph, 2) symptom duration of greater than 3 months, 3) randomized blinded placebo-controlled parallel group study design, 4) primary outcome of pain intensity within 4 weeks of treatment on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale or pain on a visual analog scale (VAS), secondary outcome of pain ay 8-12 weeks follow-up, 5) identical placebo drug. No comment was made regarding the number of reviewers and the method of settling disagreements. A total of 63 randomized controlled trials met the inclusion criteria, sampling data from 14,060 patients.
Data Extraction: WOMAC and VAS pain scores were extracted. If more than one value was available within the first 4 weeks, the time point with the greatest effect was extracted. If WOMAC data was reported using a categorical or Likert format they were converted to VAS pain scores (100mm scale). No comment was made regarding duplicate extraction.
Data Synthesis: Weighted mean differences were calculated and presented with 95% confidence intervals using an inverse variance model. When heterogeneity was present a random-effects model was used, if heterogeneity was not present a fixed-effects model was used. Heterogeneity was assessed using the Q-values (significance set at 0.05). If heterogeneity was identified plausible reasons for heterogeneity were explored by placing the data into subgroups (drug types within the same class).
What were the important findings?
What should I remember most?
How will this affect the care of my patients?
The authors responsible for this critical appraisal and ACE Report indicate no potential conflicts of interest relating to the content in the original publication.