Effect of Combined Pelvic Floor and Inspiratory Muscle Training in Women with Stress Urinary Incontinence Associated with Chronic Obstructive Pulmonary Disease: Study Protocol for a Randomized Controlled Trial

Chronic Obstructive Pulmonary Disease (COPD) is associated with respiratory muscle weakness and chronic cough, increasing intra-abdominal pressure and contributing to the development of stress urinary incontinence (SUI) in women. Although pelvic floor muscle training (PFMT) and inspiratory muscle training (IMT) have shown benefits separately, the evidence is still limited. This study protocol aims to evaluate the effect of these interventions in reducing SUI and respiratory symptoms. A randomized, double-blind clinical trial will be conducted with 76 women aged between 50 and 75 years with COPD and SUI. The protocol, registered on the Brazilian Registry of Clinical Trials-ReBEC platform - RBR-22ssh2j, will last five weeks, with two 50-minute sessions per week, using exercises for the inspiratory and pelvic floor muscles. The intervention group will perform IMT using a device initially set at 50% of maximal inspiratory pressure, with weekly progressive increases in training load. The control group will use a load of 10% of maximal inspiratory pressure, without progression. Outcomes will be assessed at baseline, post-intervention, and at 1- and 3-month follow-ups. The primary outcomes will be the severity and frequency of SUI (International Consultation Questionnaire on Incontinence - Short Form of Urinary Incontinence). Secondary outcomes will include urinary leakage (1-hour Pad Test), quality of life, Leicester Cough Questionnaire, functional capacity (6-Minute Walk Test), assessment of the diaphragm and pelvic floor muscles by electromyography, ultrasound, heart rate variability, pulmonary function by manovacuometry and spirometry, pelvic floor muscle function by bimanual palpation, and oxidative stress biomarkers: malondialdehyde, glutathione, and myoperoxamide. It is expected that the intervention may lead to improvements in urinary symptoms, respiratory function, and functional outcomes, contributing to the development of non-invasive and evidence-based therapeutic strategies for this population.