Activities with balance limitations among patients with perpheral arthritis : description and assessment

Sammanfattning: Background and aim: Patients with peripheral arthritis (PA) have several impairments that can influence balance and be risk factors for falls and fear of falling. Since disability varies among these patients, we need to know what tests are applicable for those with differing degrees of activity limitation. Only one balance capacity test, and no questionnaire on balance difficulties, has been developed for patients with PA. More differentiated balance capacity tests and self-reports validated for this group are needed in order to prescribe and evaluate balance exercise programmes tailored to individual needs. The overall aim of the work reported in the thesis was to develop the assessment of activities with balance limitations among patients with PA. Material and Methods: For Study I, three samples of 65, 19 and 22 patients with PA and different degrees of activity limitation were recruited to investigate the applicability, the inter-rater-reliability and the intra-rater reliability, respectively, of the following assessments: walking on soft material, backwards and the figure-of-eight, the balance sub-scale of the Index of Muscle Function (IMF), the Timed Up-and-Go test (TUG) and the Berg Balance Scale (BBS). In Study II, three samples of 10, 22 and 20 female patients with PA participated. Activities with perceived balance limitations were identified from qualitative semi-structured interviews. A self-administered questionnaire (BAQ-PA) based on the interviews was constructed. The BAQ-PA was reviewed regarding content, and test-retest stability was examined twice with a oneweek interval. Construct validity was investigated by correlation to previous falls, activity limitation, self-rated balance limitation, fear of falling and capacity tests. Results: In Study I, the TUG and the BBS were found applicable and most sensitive for patients with severe activity limitation. The figure of eight and the IMF were applicable and most sensitive for patients with moderate and low activity limitation. Inter-rater reliability was high (R>0.79) and intra-rater reliability was satisfactory for all assessments investigated. In Study II, perceived balance limitations were mainly related to outdoor activities. Test-retest-stability was good (Kw=0.71) for the suggested questionnaire (BAQ-PA) including 18 activities, which correlated higher to self-rated balance (rs=0.48) and activity avoidance because of balance limitation (rs=0.55) and previous falls (rs=0.49) than to capacity tests (rs<0.44), with the exception of the oneleg stance (rs=-0.75). The BAQ-PA score was significantly higher among those reporting fear of falling (p<0.05) than among those not doing so. Conclusions: Some applicable and reliable balance capacity tests were identified for patients with severe, moderate and low activity limitations. More sensitive tests should be developed for those with no assessable activity limitation. Further, the present work reports a first step towards development of a valid and reliable balance questionnaire where the patient s perspective on individual activities and wishes for improvement receive attention.