The impact of pulmonary rehabilitation and self-management support on asthma control in obese patients with asthma

Asthma is a serious health problem with increasing prevalence in the world. It
is a chronic disease which is characterized by episodes of reversible airway
obstruction due to underlying chronic airway inflammation and airway
hyperresponsiveness to different bronchial stimuli. Evidence indicates that
reduced physical activity may be associated with the severity of asthma and the
increasing asthma prevalence (Rusmussen F et al. ERJ). Several studies have
shown that physical activity improves asthma control and the quality of life of
asthma patients. However, physical training does not lead to improved lung
function.
Obesity, is another important factor that increases the risk of asthma and is
related to the severity of asthma. Compared to normal, lean asthma patients,
obese asthma patients have more missed school days per year, a lower peak flow,
a higher need of inhalation medication and less often acceptable asthma
control. The relationship with atopy, allergic rhinitis and bronchial hyper
reactivity, however, is less clear. Weight-reducing measures show a beneficial
effect on lung function, asthma symptoms, medication use and exacerbation rate.
Since, obesity and decreased physical activity level both contribute to the
asthma disease burden, a life-style intervention program with multifactorial
approach is necessary in the treatment of obese asthmatics.
Pulmonary rehabilitation is a broad therapeutic concept, and can be seen as a
life-style and a self-management support intervention. It is an ideal setting
to address the needs of people with obesity-related respiratory disorders and
individuals with lung disease in whom obesity is also contributing to
functional limitation. Data on the effect of pulmonary rehabilitation and
self-management support in obese patients with respiratory disorders are
limited. In this study we want to investigate the impact of pulmonary
rehabilitation and self-management support on asthma control and physical
condition in obese patients with not optimally controlled asthma.

To determine whether pulmonary rehabilitation (PRH) and self-management support
(SMS) is effective in terms of asthma control compared to standard care in
obese patients with suboptimally controlled asthma.

Secondary aims of the study are:
- To assess whether pulmonary rehabilitation and self-management support is
feasible in obese asthma patients.
- To determine whether pulmonary rehabilitation and self-management support in
obese asthma patients has a beneficial effect on their quality of life, lung
function, level of airway inflammation and physical condition.
- To determine whether pulmonary rehabilitation and self-management support
results in improved level of physical activity.
- To assess the usability and acceptance of life style and self-management
intervention modules of the web-based PatientCoach platform.
- To assess the incremental cost-effectiveness of pulmonary rehabilitation +
self-management support as compared to standard care.

A 3-armed randomised controlled trial. 36 obese asthma patients (BMI 30-=< 45)
with suboptimally controlled asthma ( ACQ = > 0.75) from our outpatient clinic
will be included in the study. Eligible patients will be randomly assigned to
one of the three groups. 1) pulmonary rehabilitation (PRH), 2) pulmonary
rehabilitation with self-management support (PRH+SMS) or 3) standard care.
Before and after pulmonary rehabilitation (at 3, 6 and 12 months) symptom
scores, spirometry and physical effort strain will be measured. Blood will be
sampled and sputuminduction will be performed. Patients will be followed until
12 months after pulmonary rehabilitation.

- Pulmonary rehabilitation (PRH): during 12 weeks three times a week a training
of 60 minutes under supervision of a physiotherapist, and with counselling of a
psychologist and a dietician.
- Internet based self-management program (SMS), PatientCoach, with education,
goal-setting, monitoring and action plan during PRH and during 12 months
follow-up.

The hypothesis of the study is that patient will benefit from the pulmonary
rehabilitation and self-management support. The study comprises 8 extra visits
(see study design paragraph). Most procedures are non-invasive (e.g.
spirometry, FeNO measurement, symptom score and quality of life assessment).
During the visits blood will be sampled. This procedure is invasive and may be
potential harmful as it may lead to bruises, which will resolve spontaneously.
Sputum induction is a minimal invasive technique, which is proven safe when
performed to guidelines. Nevertheless, saline inhalation may cause
bronchosconstriction. To prevent this, a short-acting β2-agonist is given
before the procedure, and pulmonary function is monitored during sputum
induction for safety reasons, in order to assess excessive bronchoconstriction.