Cystic Fibrosis
Conditions
Keywords
Exercise, Modulator therapy, Peripheral muscle function, Vascular function, Body composition, Physical activity
Brief summary
Cystic fibrosis (CF) is the most common inherited condition in the United Kingdom, affecting approximately 10,837 people. It is well recognised that regular exercise is clinically important for people with CF. Exercise function measured by the maximal oxygen consumption during a cardiopulmonary exercise test is often reduced in people with CF and this has been attributed to multiple factors including, altered heart and blood vessel function, muscle function, reduced physical activity levels and poorer sleep quality. New medicine (modulators) have become available for many people with CF. Modulators appear able to reduce sweat chloride concentrations, improve lung function and reduce the frequency of pulmonary exacerbations in people with CF. Little evidence exists to show how they may have changed the fitness and underlying mechanisms responsible for this in people with CF. This study aims to: 1. determine the exercise function 2. determine the blood vessel function 3. determine body composition 4. determine physical activity and sleep levels in people with CF on modulator therapy compared to a healthy controls group.
Detailed description
CF is the most common inherited condition in the United Kingdom, affecting approximately 10,837 people. CF affects the movement of salt and water across the body which leads to a thick sticky build up of mucus causing problems in the lungs and digestive system. CF also causes problems in other parts of the body for example, the heart, the blood vessels and muscles. This can impact a person with CFs' ability to exercise which can have impact prognosis, quality of life and increase the amount of times someone with CF is admitted to hospital due to a chest infection. For many people with CF, new medicine (modulators) have lately become accessible bringing big changes to their health. Elexacaftor-tezacaftor-ivacaftor (ETI) is the most recently approved modulator for use in people with specific CF transmembrane conductance regulator gene mutations and is now the most widely used modulator therapy. So far clinical trials have largely looked at lung function, sweat chloride levels and body mass index. The wider reaching effects of modulator therapy on exercise function has not been studied. This study will see if people with CF have blood vessel and exercise dysfunction, abnormal body composition and reduced physical activity and sleep quality when they are taking modulator therapy compared to a healthy group. The aims of this study are: 1. Determine the aerobic exercise function and mechanisms underlying this in people with CF stable on ETI and whether this is different to healthy age- and sex-matched controls; 2. Determine the peripheral muscle function in people with CF stable on ETI and whether this is different to healthy age- and sex-matched controls; 3. Determine the functional exercise capacity in people with CF stable on ETI and whether this is different to healthy age- and sex-matched controls; 4. Determine the micro- and macrovascular endothelial function in people with CF stable on ETI and whether this is different to healthy age- and sex-matched controls; 5. Determine body composition in people with CF stable on ETI and whether this is different to healthy age- and sex-matched controls; 6. Determine the physical activity levels and sleep duration and quality in people with CF stable on ETI and whether this is different to healthy age- and sex-matched controls This study will recruit 50 people with CF and 50 healthy age- and sex-matched control participants who are older than 10 years of age. It will ask them to attend the University of Portsmouth for 2 visits. The first visit will last \ 3 hours. During this time they will undergo measures on blood vessel function and aerobic exercise function. The second visit will last \ 2 hours. During this time they will undergo a body composition scan and a series of muscle function test. At home, participants will wear an accelerometer for 7 days and complete a series of questionnaires.
Interventions
None listed
Sponsors
University Hospital Southampton NHS Foundation Trust
University of Portsmouth
Study design
Observational model
CASE_CONTROL
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
10 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
for participants with cystic fibrosis: * Stable on the modulator therapy, Kaftrio® * Males and females ≥ 10 years of age * CF diagnosis based on clinical features, supported by a history of an abnormal sweat test (sweat chloride \> 60 mmol·L-1 \> 100 mg sweat), where possible, diagnostic genotyping would also be desired * Can clearly state that they are not pregnant * No contraindications to performing exercise * Can understand and cooperate with the study protocol * No increase in symptoms or weight loss in the preceding 2 weeks Inclusion criteria for healthy control participants: * Healthy males and females who are age- and sex-matched to the enrolled individuals with CF * Can clearly state that they are not pregnant * No clinical diagnosis of a chronic disease * Can understand and cooperate with the study protocol * No contraindications to performing exhaustive exercise
Exclusion criteria
for participants with cystic fibrosis: * Any non-pulmonary conditions that may impair exercise ability, such as musculoskeletal disorders and cardiovascular disease. * Unstable co-morbid asthma (daily pulmonary function variability of \>20%) * Is pregnant during the initial screening process * Unable to understand or cooperate with the study protocol due to learning difficulties or otherwise * Not of a suitable age for testing * Is a smoker or inhales any other substances * Are taking vasoactive medications
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Maximal oxygen uptake | Day 1 - baseline | Between group differences in maximal oxygen uptake derived from a maximal cardiopulmonary exercise testing on a cycle ergometer |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Oxygen uptake at the gas exchange threshold | Day 1 - baseline | Between group differences in oxygen uptake at the gas exchange threshold derived from a maximal cardiopulmonary exercise test on a cycle ergometer |
| Peak power output | Day 1 - baseline | Between group differences in peak power output derived from a maximal cardiopulmonary exercise test on a cycle ergometer |
| Time to exhaustion | Day 1 - baseline | Between group differences in time to exhaustion derived from a maximal cardiopulmonary exercise test on a cycle ergometer |
| Heart rate | Day 1 - baseline | Between group differences in heart rate derived from a maximal cardiopulmonary exercise test on a cycle ergometer |
| Near-infrared spectroscopy derived deoxygenated [haemoglobin + myoglobin] | Day 1 - baseline | Between group differences in dynamics of near-infrared spectroscopy derived deoxygenated \[haemoglobin + myoglobin\] |
| Cardiac output | Day 1 - baseline | Between group differences in dynamics of non-invasive thoracic impedance cardiography |
| Stroke volume index | Day 1 - baseline | Between group differences in dynamics of non-invasive thoracic impedance cardiography |
| Forced Expiratory Volume in the 1st second (% predicted) | Day 1 - baseline | Between group differences in Forced Expiratory Volume in the 1st second measured using flow-volume loop spirometry |
| Forced Vital Capacity (%predicted) | Day 1 - baseline | Between group differences in Forced Vital Capacity measured using flow-volume loop spirometry |
| Total minutes of physical activity (light, moderate, moderate to vigorous physical activity) | Physical activity will be measured continuously for 7 days | Between group differences in physical activity assessed via wrist-worn accelerometery |
| Sleep efficiency (time in bed + time asleep) | Sleep efficiency will be measured continuously for 7 days | Between group differences in sleep efficiency assessed via wrist-worn accelerometery |
| Peak minute ventilation | Day 1 - baseline | Between group differences in peak minute ventilation derived from a maximal cardiopulmonary exercise test on a cycle ergometer |
| Insulin iontophoresis | Day 1 - baseline | Between group differences in insulin iontophoresis measure of microvascular function |
| Percentage change in brachial artery diameter taken from the Flow Mediated Dilation assessment | Day 1 - baseline | Between group differences in Flow Mediated Dilation assessment derived from baseline brachial artery diameter and peak brachial artery diameter from flow mediated dilation measure of macrovascular function |
| Maximum quadricep strength | Day 2 - baseline | Derived from a maximal voluntary contraction |
| Quadricep fatigability index | Day 2 - baseline | Derived from change in maximal voluntary contraction |
| Handgrip strength | Day 2 - baseline | Between group difference in handgrip strength |
| Sit to stand repetitions per minute | Day 2 - baseline | Between group difference in sit to stand repetitions per minute |
| Body composition (total fat-free mass and total fat mass) | Day 2 - baseline | Derived from dual-energy X-ray absorptiometry |
| Habitual activity estimation scale | Day 2 - baseline | Between group difference in habitual activity estimation scale - answers are varied and require numerical values, percentages and/or multiple choice questions |
| Cystic fibrosis questionnaire revised | Day 2 - baseline | Between group difference in health related quality of life on a 0 - 100 scale with higher scores indicating better health related quality of life |
| The Pittsburgh Sleep Quality Index | Day 2 - baseline | Between group differences in the Pittsburgh Sleep Quality Index on a 0 - 21 scale with higher scores indicating worse sleep quality |
| Perceived exertion (breathing effort, chest tightness, throat narrowing, perceived exertion) | Day 1 - baseline | Between group differences in perceived exertion using the Dalhousie Dyspnoea and Perceived Exertion Scales during a maximal cardiopulmonary exercise testing on a cycle ergometer on a 1 - 7 scale with a higher value indicating a worse perceived exertion |
| Acetylcholine iontophoresis | Day 1 - baseline | Between group differences in acetylcholine iontophoresis measure of microvascular function |
Countries
United Kingdom
Contacts
Primary ContactZoe Saynor
Backup ContactLauren Clayton
Outcome results
None listed