Medidas de capacidade e desempenho funcionais em idosos com dor lombar crônica inespecífica: um estudo de responsividade

Abstract

Introduction: Chronic low back pain (CLBP), that is, lasting more than three months, can lead to limitations in activities of daily living and is extremely prevalent in the elderly population. Evaluating and quantifying the impact on the functionality of older people with CLBP becomes relevant to monitor and follow the evolution during treatment. Clinical outcomes in the field of LBP have traditionally focused in patient-reported outcome measures such as the Roland Morris Disability Questionnaire (RMDQ). Functional capacity tests can provide important information, with less risk of bias, to assess and monitor the evolution of older people with low back pain, as they objectively measure the individual's physical capacity to perform a task in a controlled environment. However, little emphasis has been given to capacity tests, and the responsiveness of these tests has been little investigated so far. Objective: To determine the responsiveness of three functional capacity tests and compare with the responsiveness of the RMDQ in older people with CLBP. Methods: This is a study with a methodological design. 118 older people with nonspecific CLBP were recruited. The functional capacity measures used were Timed ''Up and Go'', 5 times Sit-to-Stand Test and 4-meter walk test. The performance measure used was the RMDQ. All measures were used before and after eight weeks of treatment. Responsiveness was determined by calculating the effect size (ES), standardized response mean (SRM), correlation and analysis of the Receiver Operating Characteristic Curve (ROC curve) to calculate the area under the curve. Results: The RDMQ was the most responsive, with responsiveness values ranging from medium to large effect. About functional capacity tests, the 5 times Sit-to-Stand Test obtained the highest values, with an effect ranging from small to medium. The Timed ''Up and Go'' and the 4-meter walk test showed little effect. Only the RMDQ showed an AUC value above 0.70. The change in the RMDQ showed fair correlation with the change in the 5 times Sit-to-Stand test (r=0,34; 95%CI: 0,18; 0,49) but no correlation with changes in the other functional capacity tests (correlation coefficients ranged from 0.16 to 0.24). Conclusion: The RMDQ was the most responsive measure after a course of physical therapy treatment in older people with CLBP. Among the functional capacity tests, the 5 times Sit-to-Stand test was the test potentially able to detect changes with the intervention in older people with CLBP.