Objectives The aim of the study was to investigate differences in biomechanical factors and activity limitations between knee and/or hip osteoarthritis (OA) patients with and without cardiovascular disease (CVD).
Methods A total of 458 consecutive patients from the Amsterdam Osteoarthritis (AMS-OA) cohort were included in this cross-sectional study. All patients were diagnosed with OA of the knee and/or hip according to the ACR criteria and referred to the outpatient rehabilitation centre. All provided written informed consent. The Cumulative Illness Rating Scale (CIRS) and a specific CVD questionnaire were used to quantify CVD. Coronary diseases, heart failure and cerebral or peripheral artery diseases were considered as CVD.
Biomechanical factors were muscle strength, joint proprioception and joint laxity. Muscle strength was tested with an isokinetic dynamometer, proprioception with a joint motion detection device and varus-valgus laxity was assessed as the movement in the frontal plane in a sitting position. Activity limitations were assessed by Western Ontario and McMaster University Osteoarthritis Index physical function subscale (WOMAC-pf) questionnaire and by the get up and go (GUG) and stair-climb test.
Results In total 53 OA patients (11.6%) reported CVD. Sixteen patients (3.5%) had coronary diseases, 18 (3.7%) heart failure, 22 (4.6%) cerebral artery diseases and 3 (0.7%) peripheral artery diseases. The patient characteristics of the total OA population and differences in biomechanical factors and activity limitations between patients with and without CVD are displayed in table 1.
OA patients with a history of CVD were significantly older and more often male. They also had a significantly higher BMI compared to OA patients without CVD. OA patients with CVD had less severe OA according to the Kellgren/Lawrence score. Knee and/or hip OA patients with CVD showed lower outcomes for muscle strength, higher scores for proprioception and laxity and also higher scores for the activity limitations tests. However, only the scores on the GUG and stair-climb test were significantly higher in patients with CVD.
Flexion and extension muscle strength scores of men with CVD were significantly lower compared to men without CVD (see table 2). In woman with CVD, these scores were also lower, but only significant for the flexion score. The GUG and stairclimb scores were significantly higher in women with CVD compared to woman without CVD. For men this was only true for the stairclimb test up.
Conclusions Activity limitations and biomechanical factors differ between knee and/or hip osteoarthritis patients with and without cardiovascular diseases, whereby patients with CVD seem to have worse outcomes, compared to patients without CVD. Furthermore, there are apparent differences between men and woman. Whereas woman with CVD have significantly more activity limitations, the men with CVD have significantly less muscle strength. Future research should focus on the influence of cardiovascular disease and its risk factors on the association between muscle strength and activity limitations.
Disclosure of Interest : None declared