The elderly were under-represented in osteoarthritis clinical trials.
OBJECTIVE
Osteoarthritis is the most common disease affecting joints in the elderly. We aimed to evaluate if elderly patients are properly represented in clinical trials of diverse osteoarthritis interventions.


METHODS
Clinical trials of osteoarthritis interventions were retrieved from Cochrane Library systematic reviews (2006, issue 2). We examined the age distribution of the trial participants and eligibility criteria.


RESULTS
We analyzed data from 219 eligible trials from 18 systematic reviews. The average mean age of the participants was 63 years. Only 13 trials (6.4%) had a mean age between 71 and 80 years and only one trial had a mean age exceeding 80 years. Among trials where the age range of participants was available or could be approximately inferred, we estimated that 66 (38%) trials had not included any patients over 80 years old. Only 23 trials specifically excluded patients over 70 based on reported eligibility criteria, but 168 trials excluded patients with various comorbidities and 142 trials excluded patients receiving other specific treatments.


CONCLUSIONS
Elderly patients are considerably under-represented in clinical trials of osteoarthritis. This causes an important deficit in the utility, relevance, and generalizability of trial results for this very common condition.
Clinical and Molecular Epidemiology Unit, Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Ioannina, Greece.
George
G
Liberopoulos
Nikolaos A
NA
Trikalinos
John P A
JP
Ioannidis
D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008875:Middle Aged; D010003:Osteoarthritis / Q000628:therapy*; D018579:Patient Selection; D016032:Randomized Controlled Trials as Topic / Q000592:standards* / Q000706:statistics & numerical data; D012107:Research Design