Clinical applicability of two tests of aerobic fitness in patients with rheumatoid arthritis

Abstract

The aim of this study was to describe the clinical applicability of two different methods of aerobic fitness testing in patients with rheumatoid arthritis (RA). Five hundred and fifty-six patients with RA (median age 56 years, range 19–90, disease duration ≤6.5 years, 75% women) were included from 17 rheumatology units. Each patient was scheduled to perform a submaximal test of aerobic fitness, either on a bicycle or on a treadmill; the assignment to method was mainly determined by access to equipment at each participating unit. Eighty-eight patients (16%) were never tested, mainly because of use of beta-blockers or impairments, 45 patients (8%) terminated their tests prematurely and 423 patients (76%) completed their assigned test. Their estimated aerobic fitness was mainly classified as “low” (30%), “fair” (40%) or “average” (23%). The determinants of completing either of the tests were female gender (OR=2.06, 95% CI 1.22–3.47), age <65 years (OR=6.50, 95% CI 4.00–10.55) and no (OR=4.67, 95% CI 2.10–10.40) or mild disability (OR=6.24, 95% CI 2.43–16.06). It thus appears as if a majority of patients with RA are able to perform aerobic fitness testing despite the expected limitations related to impairments.

• Cardiorespiratory fitness
• cross-sectional
• exercise test
• methodological study
• oxygen consumption
• physiotherapy