Respiratory Biofeedback Added to Strengthening Training in Patients With Chronic Kidney Disease (RESPI-REN)

The goal of this clinical trial is to learn whether diaphragmatic biofeedback added to respiratory muscle training improves clinical and functional outcomes in adults with chronic kidney disease. It will also evaluate the feasibility and acceptability of this intervention.

The main questions it aims to answer are:

Is diaphragmatic biofeedback added to respiratory muscle training acceptable and well tolerated in patients with chronic kidney disease? Does this intervention reduce respiratory symptoms and complications in this population? Does diaphragmatic biofeedback added to respiratory muscle training improve cardiorespiratory capacity and quality of life? Researchers will evaluate diaphragmatic biofeedback combined with respiratory muscle training and a placebo intervention based on conscious breathing to assess its effects.

Participants will:

• Perform the assigned intervention three times per day for 6 weeks
• Follow a structured respiratory muscle training program with diaphragmatic biofeedback
• Be monitored for symptoms, respiratory complications, and perceived quality of life throughout the study

Study Overview

• Status: Not yet recruiting
• Conditions: Chronic Kidney Disease (Stages 4 and 5)
• Intervention / Treatment: Other: Diaphragmatic biofeedback combined with respiratory muscle training; Other: PLACEBO INTERVENTION

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Marie Carmen Valenza, PhD University Professor; Phone Number: +34 958248035; Email: cvalenza@ugr.es

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adults aged ≥18 years
• Diagnosis of chronic kidney disease (CKD) at any stage
• Clinically stable condition, with no acute medical events in the previous 4 weeks
• Ability to understand and follow breathing and training instructions
• Willingness to participate and provide written informed consent

Exclusion Criteria:

• Acute respiratory infection or unstable pulmonary disease
• Severe cognitive impairment or neurological condition limiting cooperation
• Unstable cardiovascular disease or contraindications to respiratory muscle training
• Recent thoracic or abdominal surgery (<3 months)
• Significant visual impairment that prevents proper use of the biofeedback device
• Participation in another interventional clinical trial during the study period

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Treatment Arm; Participants will receive diaphragmatic biofeedback combined with respiratory muscle training three times per day for 6 weeks	Other: Diaphragmatic biofeedback combined with respiratory muscle training; This intervention is novel because it integrates diaphragmatic biofeedback into a structured respiratory muscle training program specifically designed for patients with chronic kidney disease, a population in which respiratory dysfunction is prevalent yet under-addressed. By providing real-time feedback on diaphragmatic activity, the intervention aims to enhance motor learning, improve activation of the diaphragm, and optimize training efficiency beyond conventional breathing or respiratory muscle training approaches.
Placebo Comparator: Control Arm; Placebo intervention based on conscious breathing three times per day for 6 weeks	Other: PLACEBO INTERVENTION; The placebo intervention will consist of concious guided breathing sessions based on the participant's subjective respiratory sensations, without the use of objective physiological feedback or diaphragm-specific biofeedback. Participants will be instructed to follow standardized breathing guidance focused on perceived comfort and awareness, matching the intervention group in session frequency and duration.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants with treatment-related adverse events during intervention sessions	Adverse events and discomfort related to the intervention will also be recorded to evaluate overall number of adverse events registered during intervention period.	Baseline to 6 weeks
Respiratory Symptoms assessed by Edmonton Symptom Assessment Scale (ESAS)	Respiratory symptoms will be assessed using the validated symptom questionnaire and clinical reporting, focusing on perceived dyspnea and fatigue , and other respiratory-related complaints during daily activities. The Edmonton Symptom Assessment Scale (ESAS) is a validated instrument that assesses symptom severity, with each symptom rated on a numeric scale ranging from 0 (no symptom) to 10 (worst possible severity). Thus, higher scores indicate a worse outcome and greater symptom burden.	Baseline to 6 weeks
Respiratory Complications	The occurrence of respiratory complications during the intervention period will be monitored and recorded, including any clinically relevant respiratory events reported by participants or identified during follow-up assessments.	Baseline to 12 weeks
Quality of Life of participants evaluated by Euqol-5Dimensions questionnaire	Health-related quality of life will be assessed using a validated questionnaire to evaluate perceived physical, emotional, and functional well-being in participants undergoing the intervention. The EuroQol 5-Dimension (EQ-5D) questionnaire is a standardized measure of health-related quality of life comprising five dimensions (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression). Health states are converted into a utility index score, typically ranging from values below 0 (worse than death) to 1 (full health), where higher scores indicate better health status; additionally, the EQ-5D includes a visual analogue scale (EQ-VAS) from 0 to 100, with higher scores reflecting better perceived health.	Baseline to 6 weeks
Acceptability of intervention considering number of sessions completed by participant	Acceptability of diaphragmatic biofeedback added to respiratory muscle training will be assessed through participant completion rates.	6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cardiorespiratory Capacity evaluated using 6 Minutes Walking test	Changes in cardiorespiratory capacity will be evaluated using standardized functional or physiological assessments appropriate for patients with chronic kidney disease, aiming to determine whether the intervention improves respiratory and exercise-related capacity. The Six-Minute Walk Test (6MWT) measures functional exercise capacity by recording the total distance walked in six minutes, expressed in meters, with higher distances indicating better functional performance. There is no fixed minimum or maximum value, as results depend on the individual's physical capacity and clinical condition.	Baseline to 6 weeks

Collaborators and Investigators

• Sponsor: Universidad de Granada
• Investigators: Principal Investigator: Alejandro Heredia-Ciuró, PhD, Universidad de Granada; Study Director: Marie Carmen Valenza, PhD, Universidad de Granada

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2026
• Primary Completion (Estimated): April 1, 2026
• Study Completion (Estimated): August 1, 2026

Study Registration Dates

• First Submitted: January 8, 2026
• First Submitted That Met QC Criteria: January 18, 2026
• First Posted (Actual): January 27, 2026

Study Record Updates

• Last Update Posted (Actual): January 27, 2026
• Last Update Submitted That Met QC Criteria: January 18, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Urogenital Diseases; Pathologic Processes; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Chronic Disease; Disease Attributes; Renal Insufficiency; Pathological Conditions, Signs and Symptoms; Renal Insufficiency, Chronic; Therapeutics; Mind-Body Therapies; Complementary Therapies; Exercise Movement Techniques; Physical Therapy Modalities; Breathing Exercises
• Other Study ID Numbers: SICEIA-2024-003384

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No