Minimal Important Difference for the Glittre-ADL Test and London Chest Activity of Daily Living Scale

Background: The ability to perform activities of daily living (ADL) in patients with chronic obstructive pulmonary disease is often impaired. Glittre-ADL Test has been used to assess limitations in ADL, and it seems to be responsive to intervention. However, the minimal detectable change for Glittre-ADL Test remains unknown. Design: Non-controlled before and after study. Setting: The study will be conducted in an outpatient pulmonary rehabilitation program in Florianopolis, Brazil. Subjects: Patients with COPD (GOLD II-IV). Interventions: Pulmonary rehabilitation program based on physical training, conducted over 24 sessions supervised, three times a week, including aerobic training in treadmill and localized training for upper limbs and lower limbs. Main measures: Glittre ADL-Test performance, six-minute walk test performance, London Chest Activity of Daily Living score, Modified Medical Research Council score, COPD Assessment Test score, Saint George Respiratory Questionnaire score before and after the pulmonary rehabilitation program.

Assigned Interventions: Pulmonary rehabilitation program (PRP) was conducted according to the guidelines of the American Thoracic Society/European Respiratory Society (ATS/ERS). Physical training was conducted over 24 sessions supervised, three times a week. The program included aerobic training in treadmill (with 30 min load determined by the dyspnea sensation - 4 to 6 on the modified Borg scale) and localized training for upper limbs with free weights or elastic bands (movements performed based on the proprioceptive neuromuscular facilitation diagonals, performed in two series, lasting two minutes each) and lower limbs (quadriceps and triceps sural) with free weights and/or in the bodybuilding station .

Pulmonary function test: Spirometry will be performed before the PRP, and it will be in accordance with ATS/ERS standards in order to provide the level of pulmonary obstruction and severity of disease. The predicted values will be calculated with the equations derived from Brazilian population.

Glittre-ADL Test: The patients will be instructed to complete five laps on the follow circuit as quickly as possible: from a sitting position, the subject stands up and walks along a flat 10-m long course, in the middle of which there is a two-step ladder (each step 17 cm high x 27 cm deep) to be climbed; after completing the 10 m, the subject faces a shelf containing three 1-kg objects positioned on the top shelf (shoulder height) and moves them one by one to the bottom shelf (waist height) and then to the floor; the objects are then returned to the bottom shelf and finally to the top shelf again; the subject walks back, climbing up and down the steps, until reaching the starting point (chair), sits down and immediately begins the next lap. The subjects carry a weighted backpack (2.5 kg for women, 5.0 kg for men). Two Glittre-ADL Tests will be conducted before and after the PRP.

Six minute walk test (6MWT): The patients will be instructed to walk in order to perform the largest distance during six minutes. The walking speed will be selected by the patient, according to the guidelines of the ATS. Two 6MWTs will be conducted before and after the PRP.

London Chest Activity of Daily Living scale: Patients will be asked about their perception of limitation in activities of daily living, using the London Chest Activity of Daily Living scale (LCADL) before and after the PRP.

Modified Medical Research Council scale: Patients will be asked about their perception of dyspnea, using the modified Medical Research Council scale before and after the PRP.

Saint George Respiratory Questionnaire: Patients will be asked about their perception of health-related quality of life, using the Saint George Respiratory Questionnaire before and after the PRP.

COPD Assessment Test (CAT): Patients will be asked about their perception of the impact of COPD (cough, sputum, dyspnea, and chest tightness) on health status, using CAT before and after the PRP.

Eligibility Criteria:
Inclusion Criteria:

* Clinical diagnosis of COPD confirmed by spirometry (COPD GOLD stages II, III and IV)
* Absence of change in respiratory symptoms in the past four weeks
* No hospital admission in the past 12 weeks
* Age between 40 and 80 years old

Exclusion Criteria:

* Any other disease or health condition that could compromise the test´s execution or physical training
* Participation in pulmonary rehabilitation program completed in the last six months
* Interruption of pulmonary rehabilitation program for any reason
* Current smoking or its cessation in less than six months
* Any change in symptoms during the study protocol assessments