The prospective, longitudinal Multicenter Osteoarthritis (MOST) study found several risk factors for rapid loss of articular cartilage in the knee but the only demographic risk factor present at baseline was a high body mass index (BMI).
Dr. Frank W. Roemer at Boston University Medical Center and the MOST study team reported that the progressive course of osteoarthritis is usually slow.
However, it would be useful to identify a subgroup of patients with no or early disease who are at high risk for fast cartilage loss, the authors write. Such patients would be ideal for testing new treatments and should have the greatest need for preventive maneuvers or treatments.
The aim of the MOST study was to identify predictors of fast tibiofemoral joint cartilage loss over 30 months in subjects with little or no structural osteoarthritis at baseline. The study involved 347 knees in 336 subjects with mean age 61 years and mean BMI 29.5 kg/m.
MRI of the knees identified that 74.1% had no cartilage loss, 20.2% exhibited slow cartilage loss, and 5.7% had rapid cartilage loss.
Dr. Roemer’s group found that for each unit increase in BMI, the odds of fast cartilage loss increased by 11% (p = 0.04) regardless age, gender, and ethnicity.
Other strong indicators of fast cartilage loss were meniscal tears (adjusted OR 3.19, p = 0.03) or extrusion (adjusted OR, 3.62, p = 0.01), synovitis or effusion (adjusted OR 3.36, p = 0.07) and any high-grade MR-depicted feature, (adjusted OR 8.99, p < 0.001).
Patients with these risk factors may be ideal subjects for preventative or treatment trials, Dr. Roemer and associates advise.