AKA "Degenerative joint disease," "Osteoarthrosis"
I. Epidemiology
- Prevalence increases w/age, most frequently starts in 40's
- Slight female predominance
II. Pathogenesis--multifactorial
- Thought to result from "normal stresses on abnormal cartilage or abnormal stresses on normal cartilage"
- Abnormal stresses include trauma, joint infection, and crystalline arthropathies but apparently not chronic aggressive exercise
- Genetic predisposition (perhaps leading to susceptible cartilage makeup) appears to be present
III. Clinical features
- Arthralgias worse with joint use, most commonly in PIP, DIP, carpometacarpal, and first MCP joints; also spine, hips, and knees
- Less stiffness than in inflammatory arthritides, e.g. rheumatoid arthritis
- Minimal signs of inflammation and no known extra-articular features
- Radiographic features (usually develop well in advance of sx): joint space narrowing, periarticular bone spur formation, subchondral bonen sclerosis
IV. Treatment
- In 98 pts with knee DJD, Glucosamine 500mg TID was not ass'd with any improvement in pain scores at 60d c/w placebo (West. J. Med. 172:95, 2000--AFP)
- A meta-analysis of 6 randomized trials found sig. effect on symptomatic and functional outcomes in glucosamine c/w placebo (also included analysis of 9 trials of chondroitin sulfate; JAMA 283:1469, 2000--abst)
- 212 pts with knee osteoarthritis randomized to glucosamine 1500mg QD vs. placebo; at 3y f/u, sig. diff. in loss of joint space and in symptom scores (favoring glucosamine) (Lancet 357:247, 2001--JW)
- In a study in 205 pts with knee OA > 45yo randomized to glucosamine 1.5g/d vs. placebo x 12wks, there were no differences in various pain and function scores (Am. J. Med. 117:643, 2004--AFP)
- In a study in 1,583 pts with symptomatic osteoarthritis randomized to glucosamine/chondroitin (1.5g/1.2g daily), either alone, celecoxib 200mg/d, or placebo x 3mos. Incidence of the main outcome (20% decrease in pain score at 6mos) was not sig. diff. for glucosamine, chondroitin, or both vs. placebo ("Glucosamine/Chondroitin Arthritis Intervention Trial" ("GAIT"); NEJM 354:795, 2006--FP News 3/15/06)
- In a study in 318 pts with knee osteoarthritis randomized to glucosamine sulfate 1500mg QD, Acetaminophen 1g TID, vs. placebo, at 6mos, the glucosamine (but not the acetaminophen) recipients had sig. reductions in mean pain/limitation-of-function scores (Arth. Rheum. 56:555, 2007--JW)
- Chondroitin sulfate
- A component of articular cartilage
- In a meta-analysis of 7 randomized trials involving 703 pts w/knee- or hip osteoarthritis. Chondroitin was ass'd with sig. more pain reduction and improvement in function than placebo. No significant adverse effects were noted. (J. Rheum. 27:205, 2000--JW)
- A meta-analysis of 9 randomized trials found sig. effect on symptomatic and functional outcomes in glucosamine c/w placebo (also included analysis of 6 trials of glucosamine sulfate; JAMA 283:1469, 2000--abst)
- In a study in pts 40-85yo with symptomatic knee osteoarthritis but no severe changes on radiography randomized to chondroitin 4 & 6 sulfate 800mg/d vs. placebo x 2y; after 2y, there was sig. less progression in joint space narrowing in chondroitin group but no sig. diff. in change in pain between the groups (Arth. Rheum. 52:779, 2005--AFP)
- In a study in 622 pts with knee osteoarthritis randomized to chondroitin sulfate 800mg/d vs. placebo, over 2y f/u, CS pts had sig. lower pain scores during the first year but not the second year; joint narrowing was sig. lower in CS pts (Arth. Rheum. 60:524, 2009-JW)
- In a meta-analysis of 20 randomized trials of chondroitin involving 4,056 pts with knee or hip osteoarthritis, with median treatment duration 25 weeks and median daily dose 1000mg, chondroitin use was associated with a sig. improvement in pain scores, though there was extensive heterogeneity among the trials; analysis of just the three trials that had intention-to-treat data revealed no effect on pain (Ann. Int. Med. 146:580, 2007-JW)
- Diacerein
- Not available in U.S. as of 2006
- In a meta-analysis of 19 randomized trials involving total 2,637 pts with either placebo or NSAID control, diacerein was sig. better than placebo and not sig. diff. from NSAIDs at reducing pain and improving function. Diacerein was associated with sig. better outcomes 3mos after discontinuation of tx compared with NSAIDs. Associated with mild-moderate diarrhea (mostly early in treatment course) and darkening of urine. (Arch. Int. Med. 166:1899, 2006--FP News)