Effect of pre-surgical pulmonary rehabilitation on outcomes of bariatric surgery in morbidly obese patients with asthma

The prevalence of obesity has dramatically increased in the Netherlands over
the last years. On average, the percentage of subjects with overweight (BMI> 25
kg/m2) has increased more than 50% during the last 30 years. In 2010, 10% of
the Dutch men and 13% of the Dutch women had obesity (BMI>30 kg/m2) (Centraal
Bureau voor Statistiek, Permanent Onderzoek LeefSituatie (CBS-POLS)).
Epidemiological studies have shown that obesity increases the risk of asthma
and is related to the severity of asthma. In a previous study we have
demonstrated that bariatric surgery has a proven beneficial effect on symptoms
and lung function in obese patients with asthma. However, bariatric surgery is
an expensive therapy and has potential unwanted side-effects and complications.
Besides, bariatric surgery does solve the problem of overeating, but it does
not address other problems such as behaviour or lifestyle. Therefore, a debate
has emerged whether lifestyle adjustment by means of intensive physical
training before bariatric surgery can improve the outcomes of bariatric surgery
and can decrease the complication rate in these asthmatic patients. Pulmonary
rehabilitation is a broad therapeutic concept, and can be seen as a life-style
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 in obese patients with respiratory disorders are
limited.
In this study we want to investigate the effect of pre-surgical pulmonary
rehabilitation on outcomes of bariatric surgery in severe obese patients with
not optimally controlled asthma. The hypotheses is that pulmonary
rehabilitation prior to bariatric surgery is effective by means of outcome
(asthma control, complications, recovery, physical condition, quality of life)
after the bariatric surgery.

To determine whether pulmonary rehabilitation prior to bariatric surgery leads
to improved and sustained asthma control (ACQ) as compared to bariatric surgery
alone in patients with morbid obesity and not optimally controlled asthma.


Secondary aims of the study are:

- To determine whether pre-surgical pulmonary rehabilitation in severe obese
asthma patients has a beneficial effect on their quality of life, lung
function and physical condition.
- To assess whether pulmonary rehabilitation is feasible in morbidly obese
asthma patients.
- To determine whether pre-surgical pulmonary rehabilitation results in
improved physical activity level.
- To determine whether pulmonary rehabilitation prior to bariatric surgery
results in less peri-operative complications.
- To assess the incremental cost-effectiveness of pulmonary
rehabilitation + laparoscopic bariatric surgery as compared to laparoscopic
bariatric surgery alone.
- To determine whether pulmonary rehabilitation results in a
lower degree of systemic inflammation in obese asthma patients before and after
bariatric surgery.
-- To determine the relationship between bronchial inflammation in obese
asthmatics and the low-grade systemic inflammation in obesity.

Randomized controlled trial. Thirty-five morbidly obese asthma patients will be
randomized (2:1) to either 12 weeks of pulmonary rehabilitation or 12 weeks no
intervention before laparoscopic bariatric surgery. Before and after the
bariatric surgery symptom scores, spirometry and physical effort strain will be
measured. Blood samples will be taken. The total follow-up of the study will
be twelve months after bariatric surgery.

Pulmonary rehabilitation: 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. .

Laparoscopic bariatric surgery: either a gastric sleeve gastrectomy or a
Roux-and-Y gastric bypass surgery. During the surgery, subcutaneous and
visceral fat tissue biopsy will be performed for analysis.

Patients in the intervention group are expected to have individualised
treatment benefit from the study. The study comprises nine visits (see study
design paragraph). *Visit 0* and *visit 5* are already standard practice for
subjects in the bariatric surgery programme of the Sint Franciscus Gasthuis.
Also pulmonary rehabilitation is already often practised for patients with
uncontrolled asthma despite adequate medication. Most procedures are
non-invasive (e.g. spirometry, FeNO measurement, symptom score and quality of
life assessment). Only one procedure is invasive and may be potential harmful.
During the visits blood samples will be taken on five occasions (60 ml). This
may lead to bruises, which will resolve spontaneously.