Chronic Beta-blockade and Cardiopulmonary Exercise in COPD
Condition: Chronic Obstructive Pulmonary Disease
MeSH terms: Lung Diseases; Lung Diseases, Obstructive; Pulmonary Disease, Chronic Obstructive
Study type: Interventional
Phase: Phase 4

Summary: 
      What are the differential effects of beta-blockers on lung and heart function during exercise
      in chronic obstructive pulmonary disease (COPD)? COPD is a major cause of illness and death.
      Not only do these individuals suffer from lung disease, but COPD often leads to other
      illnesses, particularly heart disease. Beta-blockers very successfully treat heart disease.
      It is therefore logical that one would want to use this treatment in COPD patients with heart
      disease too. However, there has always been concern that beta-blockers could cause
      significant problems in COPD by worsening lung function, as these can have the opposite
      effect to inhalers used to treat COPD that open up airways. Pointedly, there is increasing
      evidence that despite this problem, COPD patients who have been prescribed beta-blockers have
      been shown to gain benefit particularly in terms of preventing death.

      In this study, the investigators therefore want to examine which beta-blocker might be the
      safest for COPD patients, as each work slightly differently. Some beta-blockers may have a
      more beneficial effect on airways than others, whilst still benefitting the heart. The
      investigators will study two different beta-blockers; one that potentially narrows airways
      and one that potentially opens airways. The investigators will be using cardiopulmonary
      exercise testing (an exercise bike that measures both heart and lung function during
      exercise) to look for differences between both beta-blockers primarily in terms of lung
      function but also with information about the heart. The investigators will recruit people
      with moderate to severe COPD who are able to complete a cycle exercise test through their
      respiratory research department. The study will last for 10-12 weeks with 5 main visits to
      the department for serial exercise tests, breathing tests, simple heart function tests and
      simple blood tests that will tell the investigators what other effects these beta-blockers
      are having on the heart and lungs.
    

Detailed description: 
      Chronic obstructive pulmonary disease (COPD) is a major cause of illness and death. In fact,
      by 2020, the World Health Organization predicts that COPD will become the third leading cause
      of death (currently fourth), and the fifth leading cause of disability (currently twelfth)
      worldwide. COPD and cardiovascular (heart) disease are intertwined due to the associated risk
      of smoking related atherosclerosis. Beta-blockers are generally avoided in COPD patients due
      to the associated risk of worsening lung function and acute bronchospasm (airway narrowing)
      due to beta-2-receptor blockade. Despite these concerns a recent Cochrane review has shown
      that chronic beta-blockade with "cardioselective" beta-blockers (for example bisoprolol) that
      preferentially block beta-1 (mostly heart) over beta-2 (mostly airway) receptors are well
      tolerated with less beta-2-blockade and subsequently less bronchospasm.

      Furthermore, observational studies evaluating the impact of beta-blocker use in COPD patients
      have shown benefits on survival with beta-blockers. We have published retrospective data from
      5,977 patients with COPD with a mean follow up of 4.35 years, showing that patients using
      beta-blockers (88% cardio-selective) produced a 22% overall reduction in death as well as
      significant reductions in respiratory hospital admissions and oral steroid use.

      Beta-blockers are pharmacologically different and there now needs to be an assessment of the
      clinical consequences of different beta-blockers in COPD. Despite being "cardioselective",
      bisoprolol still shows significant beta-2-receptor blockade at usual treatment doses, which
      results in a significant worsening in Forced Expiratory Volume in 1second - FEV1 (a major
      marker of lung function) following chronic use. Celiprolol however is a unique beta-blocker
      which in addition to its beta-1-receptor blockade has partial beta-2-agonist activity and
      therefore it does not cause bronchoconstriction or interact with short and long acting
      beta-agonist inhalers which are the mainstay of COPD treatment. Thus celiprolol might confer
      an ideal profile for use in COPD (i.e. good for heart and not detrimental to lungs),
      especially in more severe patients where even a small fall in FEV1 might have significant
      consequences on their breathing and exercise capacity.

      Poor exercise tolerance is associated with worsening quality of life and increased risk of
      death and thus provides a valuable surrogate marker of death. Worsening respiratory symptoms
      in COPD patients are more commonly seen on exertion than at rest, and associated with
      abnormal increases in lung volumes where air that is breathed in becomes trapped and cannot
      completely escape when breathing out (dynamic hyperinflation).

      Cardiopulmonary exercise testing provides a global assessment of both respiratory (lung) and
      cardiovascular (heart) response to exercise. Whilst studies have shown a worsening of dynamic
      hyperinflation with bisoprolol, due to their differing pharmacological properties it might be
      that celiprolol will not result in worsening dynamic hyperinflation, whilst also
      demonstrating improvement in cardiovascular outcomes such as stroke volume (the pump function
      of the heart) and heart rate recovery following exercise. Whether these effects result in an
      improved exercise tolerance is unknown. Another interesting property of celiprolol is reduced
      cholesterol and increased High Density Lipoprotein (HDL) fraction conferred by partial
      beta-2-agonist activity. We will also measure serum markers of cardiac dysfunction (B-type
      Natriuretic Peptide (BNP) and Galectin-3) and their response to beta-blockade which to the
      investigators' knowledge has never been performed in a COPD study.

      With regards to measuring cardiovascular outcomes of cardiac output and stroke volume, the
      investigators plan to use a novel non-invasive monitor which is based on the phenomenon of
      bioreactance that occurs when a small alternating current is passed through the chest. To the
      investigators' knowledge this device has never been used when assessing cardiovascular
      response to beta-blockers during exercise, but it is safe and easy to perform at the same
      time as the standard exercise test.

      The investigators therefore wish to assess the relative effects of both celiprolol and
      bisoprolol in COPD patients and establish whether the proposed benefits on survival with
      beta-blockers in COPD are reflected in improved cardiovascular and respiratory response to
      exercise and importantly exercise tolerance. The investigators also want to see if celiprolol
      is superior to bisoprolol on these markers (particularly lung function) as described above.

      The information gathered from this study will be invaluable as it will provide further
      information about the effects of beta-blockers in COPD and will be used to pump-prime larger
      long-term studies examining the effects of beta-blockers on survival in many more COPD
      patients.

      Hypothesis The null hypothesis is that there is no difference between bisoprolol and
      celiprolol in terms of cardiorespiratory outcomes during incremental exercise testing in
      patients with moderate to severe COPD - specifically no difference in the proposed primary
      outcome measure of dynamic hyperinflation during cycle endurance testing.

      Design The investigators have chosen a randomised crossover design to answer this question
      because it is unknown which, if either, beta-blocker might be better for lung function and
      exercise capacity in moderate to severe COPD patients. The crossover design allows the use of
      the same patients as their own comparators, thus allowing the investigators to expose fewer
      patients to these medications with the same statistical power as a parallel group study
      (different patients in each group). Each participant will therefore receive both treatments
      in sequence but with their initial one decided at random using a randomisation algorithm.
      Importantly the investigators have not used a placebo control arm here, as it is already
      known that beta-blockers are of benefit to COPD patients (particularly those with
      cardiovascular disease) whereas placebo provides no benefit. In other words the investigators
      are drilling down to see which particular medication has the most beneficial therapeutic
      profile. The justification for using open-label beta-blockers is that this is a pilot study
      and it helps to keep the overall costs of the study down at this stage of investigation.

      Methods The investigators will perform a randomised, cross-over, open label trial of
      bisoprolol versus celiprolol with 10 people who have moderate to severe COPD. The study will
      last between 10-12 weeks for each person. Potential participants will be recruited from our
      existing database of volunteers with COPD, contacted either by telephone, email or post and
      invited to participate. Those invited will receive a written patient information document
      detailing the requirements of the study and the extent of their participation before
      attending for a screening visit. Participants will be given at least 24hours to read the
      information document before deciding whether or not they agree to be screened. The study will
      include 5 visits to the department (including the screening visit) for the various tests
      outlined below. Each visit may last for around 3 hours. If participants agree to coming along
      for a screening visit, they will be asked to withhold any long-acting bronchodilators for
      48hours and short acting bronchodilators for 6 hours as is standard practice when confirming
      the diagnosis of airway obstruction / COPD using clinical pulmonary function measurements.

      Screening Visit At the screening visit, the information document will be discussed with the
      participant and written informed consent will be obtained if they agree to take part in the
      study. The following will then be performed: a general medical examination by a doctor; a
      pregnancy test for all females; lung function measurements (spirometry, impulse oscillometry,
      reversibility to salbutamol); heart function measurements (resting ECG [electrocardiogram],
      echocardiogram where possible if not done in last year); vital signs (oxygen levels, blood
      pressure, pulse); 'practice' cardiopulmonary exercise test (to confirm ability to cycle and
      to counter any 'learning effect' from future baseline exercise test); baseline blood tests.
      Inhaler technique will also be assessed and confirmed adequate. Participants found to be
      eligible for the remainder of the study after these tests will proceed through a 1 week
      run-in period on their usual medications before coming back for the first (baseline) visit.
      Those who do not fulfil the study criteria will continue on their usual medication and their
      General Practitioner (GP) informed of any medically relevant data. Eligible participants will
      be provided with portable monitors to measure their own lung function, pulse and oxygen
      saturations at home twice daily to be recorded in a daily diary which will also include
      details of their reliever use and symptoms. This diary will be kept throughout the study.

      Study visits Prior to participants attending for their first (baseline) study visit they will
      be asked to only withhold their short-acting reliever inhaler for 6 hours. Participants will
      not be required to withhold any long-acting bronchodilators for study visits as we are
      assessing any effects of the beta-blockers in addition to these standard treatments and we
      will have confirmed the diagnosis of COPD at the screening visit. Diary cards will be
      reviewed and the following measurements will be recorded at visit 1: resting lung function
      (impulse oscillometry, spirometry, whole body plethysmography); resting ECG; vital signs; St
      George's Respiratory Questionnaire (disease specific quality of life questionnaire); blood
      sample (BNP, Galectin, Cholesterol/HDL, Creatine Kinase (CK), Potassium); cardiopulmonary
      exercise test. Provided the participant's measurements still correspond to the inclusion and
      exclusion criteria for the study, they will be randomised to one of the two beta-blocker
      treatments: Bisoprolol (2.5mg daily for 2 weeks, then 5mg daily for approximately 2 weeks) OR
      Celiprolol (200mg daily for 2 weeks, then 400mg daily for approximately 2 weeks).
      Beta-blockers will be up-titrated at home after 2 weeks with advice about contacting us if
      side effects develop. Participants will be contacted both before and after this up titration
      either by telephone or email. However, if adverse effects occur on the higher dose, then
      participants will be allowed to drop back to the lower dose for the remainder of the study
      period. At the end of each treatment period, study measures will be repeated as above. After
      visit 2 participants will have an approximately 1 week washout period prior to being given
      the alternate beta-blocker treatment.

      End of study After visit 4 each participant will have completed the study and they will be
      returned to their usual medications. The overall study will be complete when the last
      enrolled participant completes the protocol.

      Analysis and final reporting All analyses will be performed at the end of the study. There
      will be no interim analysis. The report will be published in a high impact peer reviewed
      journal.
    

Intervention name(s): Bisoprolol; Celiprolol
Intervention type(s): Drug; Drug
Intervention description(s): 2 weeks of Bisoprolol 2.5mg daily then 2 weeks Bisoprolol 5mg daily; 2 weeks of Celiprolol 200mg daily then 2 weeks Celiprolol 400mg daily
Intervention MeSH terms: Celiprolol; Bisoprolol
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Beta-blocker; Cardiopulmonary exercise testing