Download View

Tips for Caring for
Patients with Reactive
Airways
Jason E. Knuffman, MD
Allergy
October 27, 2004
Objectives for CME
• Review the goals of asthma care
• Review the fundamental therapeutic
options for asthmatics
• Recognize allergic asthmatic patients who
would potentially benefit from referral to a
specialist
• This talk has not been sponsored by any
organization
Outline
•
•
•
•
•
Impact of Asthma
Goals of Therapy
Conventional Treatment of Asthma
Allergic Asthma
Referral Indications
Impact of Asthma
• 15 million persons with asthma in U.S.
• 4.8 million children – most common
chronic disease of childhood
• 478,000 hospitalizations and 4,400 deaths
per year
– A disproportionate rate among African
American and Hispanic populations
Middleton
Goals
•
•
•
•
•
•
•
•
Identify asthma triggers
Correct inhaler or device technique
Focus on long-term control of symptoms
Maintaining normal daily activities, including
exercise
Minimize ER or urgent care visits
No medication side effects
Recognize signs of impending exacerbation and
execute action plan
Education
Middleton
Conventional therapy
• Environmental control
– Need to identify what patient is allergic to by
skin or serum testing
– Identify respiratory irritants (cigarette smoke,
pollutants, perfumes etc.)
– Aspirin sensitivity
– Vigorous attempts at smoking cessation are
considered first-line therapy equivalent!!!
Middleton
Environmental Control cont…
• House dust mite (HDM) measures
–
–
–
–
–
Removal of carpet, upholstered furniture
Mattress and pillow encasements (~$100)
Routine hot-water washing of bedding
Humidity <50%
Less useful options are HEPA filters and other air
filters (not recommended)
• For pets, avoidance is key
– Periodic exposure exception
Middleton
Pharmacotherapy
• Two key goals of therapy:
– Reduce airway inflammation
– Improve symptom control
Controller Medications
• Daily usage:
– Inhaled Corticosteroids
– Long acting ß-2 agonists
– Methylxanthines
– Mast Cell Stabilizers
– Leukotriene Modifiers
Pharmacotherapy
• Inhaled Corticosteroids (ICS)
– Drugs of choice for management of persistent asthma
– Strong data from randomized, double-blinded,
placebo controlled trials in children and adults
supports their efficacy
– Compared to short-acting ß2 agonists¹ alone without
a controller med
•
•
•
•
•
Improvements in pre-bronchodilator FEV1
Reduced airway responsiveness
Reduced symptom scores and frequency
Fewer courses of oral corticosteroids (OCS)
Lower hospitalization rates
¹ Childhood Asthma Management Program trial et al from 2002 update
Comparing ICS to other
controllers
• Long acting ß agonists vs. ICS
– ¹Those using salmeterol as monotherapy had
deterioration in FEV1 over time
• Theophylline vs. ICS
– ²ICS reduced symtoms,supplemental
bronchodilators, OCS needs, bronchial
hyperresponsiveness and eosinophilia
– No outcomes were improved with theophylline
– May get small steroid-sparing effect
¹Verberne et al.1997; ²Reed et al 1998
Comparing ICS to other
Controllers
• Nedocromil
– ¹CAMP trial found no difference between
nedocromil and placebo in:
• Lung function
• Symptom scores
– Nedocromil DID reduce use of OCS and
reduced number of urgent care visits over
placebo
– Results strongly favored ICS over nedocromil
when they were compared on all endpoints
¹CAMP data
Pharmacotherapy
• Leukotriene Modifiers
– 5-lipoxygenase inhibitors (zileuton-discontinued)
– Leukotriene receptor antagonists (zafirlukast and
montelukast)
– Add-on therapy to ICS
– If used as monotherapy, there has been shown to be
modest improvement in lung function in adults and
children compared to placebo
– Again, ¹ICS significantly and clearly favored over
LTRA’s in persistent asthma
¹Busse et al, 2001
Pharmacotherapy
• Mast Cell Stabilizers
– Nedocromil and cromolyn
– Used for preventative purposes only
– Could be considered for treatment of
persistent asthma
– NOT preferred, though
Pharmacotherapy
• Long Acting ß agonists
– ¹164 patients ages 12-65 with well controlled asthma
on ICS
•
•
•
•
Randomized to continued ICS vs. LABA
16 week study
LABA group had more treatment failures (24% vs. 6%)
LABA group with more exacerbations (20% vs 7%)
– Evidence supports steroid-sparing effect
– Can be useful for exercise-induced bronchospasm
¹Lazarus et al 2001
Rescue Medications
• As-needed usage:
– Short acting ß agonists
– Oral corticosteroids
Pharmacotherapy
• Short-acting bronchodilators
– Numerous tradenames
• Albuterol, pirbuterol
– Drug of choice for “rescue”purposes
– NOT for scheduled usage
– Usage reflects control
– Can be used as monotherapy in exerciseinduced asthma
Pharmacotherapy
• Oral Glucocorticoids
– The most potent treatment for asthma
symptoms
•
•
•
•
Decrease inflammatory cell function and activation
Stabilize vascular leakage
Decrease mucus production
Increase B-adrenergic response
– Work by binding intracellular glucocorticoid
receptors and inhibiting transcription of target
genes
Middleton
Oral Glucocorticoids, cont…
• Can be used as a ‘short burst’ to win back
control of asthma symptoms
– ie, prednisone 10mg bid-tid for 5-7 days, then
stop – warn of usual SE’s (increased appetite,
sporadic glucose readings, psychiatric etc…)
• Consider methylprednisolone usage if psychiatric
SE’s are a concern
– Keep prednisone ‘burst supply’ at home – a
good idea with compliant patients
NAEPP
Miscellaneous Topics
• Exercise-induced bronchospasm
• Severe, life-threatening asthma
• PREGNANCY…
Asthma in Pregnancy
• New guidelines are forthcoming –
November 2004
• [email protected]
• http://www.nhlbi.nih.gov/about/naepp/
• National Asthma Education
and Prevention Program
Allergic Asthma
• Allergen immunotherapy
• Anti-IgE therapy
Allergen IT
• Immunotherapy for allergic rhinitis has clearly
proven useful
• IT for asthma demands more carefully selected
candidates, and in correct setting is also very
effective
• IT is a long-term commitment for the patient
– Weekly buildup, initially
– Monthly maintenance thereafter
– Usually continue shots for 3-5 years
Middleton
Allergen IT
• ¹No new randomized, controlled trials for IT
literature in adult asthmatics over last 5 years
• ²Cochrane Airways Group selected RC trials
using allergen-specific IT to treat asthma
– 75 trials, 3,506 participants
– Various antigens used
– There was observed an overall significant reduction in
asthma symptoms and medication usage as well as
improvement in bronchial hyperreactivity with IT
• NNT=4 to prevent 1 patient with worsening symptoms
• NNT=5 to prevent 1 patient from requiring increased meds
¹Norman 2004 ²Abramson 2003
Abramson 2003
Anti IgE
Omalizumab
Busse and Lemanske 2003
Anti-IgE Therapy
• Omalizumab (Xolair)
– Approved in 2003 for moderate to severe
asthma
– Monoclonal antibody, binds IgE
– Shown to reduce asthma exacerbations
– Reduces need for oral CSs and reduces dose
of ICSs
Rambasek et al 2004
Omalizumab, cont…
• Indications:
– Perennial allergic asthma (positive skin
testing perennial allergens such as dust
mites, cats, dogs, cockroaches)
– IgE level between 30 and 700 IU/ml.
– 12 yo and older
Rambasek et al 2004
Omalizumab cont…
• Busse et al, RPCDB trial
– 525 patients with severe allergic asthma,
poorly controlled, requiring daily ICS
– placebo or omalizumab
– kept constant dose of ICS for 16 weeks, then
12 week taper
– primary outcome: # of asthma exacerbations
– secondary outcome: mean reduction of ICS
dose
Busse et al. JACI 2001; 108: 184-90.
Busse et al
Busse et al
Busse et al
Busse et al
Omalizumab, cont…
• Administration:
– Dosed by formula incorporating body weight
and IgE level
– Subcutaneously, every 2-4 weeks depending
on the dose
– Need to monitor in office for urticaria (2-3%)
or anaphylaxis (0.01-0.1%)
– Average cost between $5,000 and $25,000
per year
Rambasek et al 2004
Referral Indications
•
•
•
•
•
•
Is it asthma?
Allergic component
Significant morbidity, altered lifestyle
Steroid-dependent
Overuse of beta agonists
Education
Conclusion
•
•
•
•
•
Impact of Asthma
Goals of Therapy
Conventional Treatment of Asthma
Allergic Asthma
Referral Indications
???’s