Article

The majority of interventions for knee osteoarthritis aim to reduce
knee pain with the assumption that improvements in function will automatically
follow. However, this assumption is not universally true, and a paradoxical
decline in function is not uncommon following reduction in knee pain.
The purpose of this study was to examine what factors beyond knee pain are
important for functional decline among people with reductions in knee pain.
DESIGN: This was an observational cohort study. METHODS: The Multicenter
Osteoarthritis Study (MOST) is a National Institutes of Health-funded
longitudinal study of people who have or are at high risk for knee
osteoarthritis. This study included individuals who had a meaningful reduction in
pain in either knee over 30 months, defined as a 41% decrease in visual analog
scale pain score with an absolute decrease of >/=20/100. Meaningful decline in
walking speed was defined as a decrease of 0.1 m/s during a 20-m walk. To examine
the association of risk factors with meaningful decline in walking speed, risk
ratios were calculated and adjusted for potential confounders. RESULTS: Of the
465 people with a meaningful reduction in knee pain (mean [SD] age=63.3 [7.8]
years, 67% female, 82% Caucasian, mean [SD] body mass index=31.3 [6.3] kg/m(2)),
20% had a meaningful decline in walking speed. Adjusting for confounders,
participants with new comorbidity and those with widespread pain had 1.8 and 1.7
times the risk of decline compared with their counterparts with no comorbidity or
widespread pain (adjusted risk ratio=1.8 [95% confidence interval=1.1-3.0] and
1.7 [95% confidence interval=1.1-2.8], respectively). LIMITATIONS:
Generalizability is limited to people with a reduction in knee pain. CONCLUSIONS:
Reductions in knee pain are not always accompanied by improvements in walking
speed. Health providers should consider that the onset of new comorbidity and
presence of widespread pain may increase the risk of functional decline despite a
reduction in knee pain.

Langue : ANGLAIS