Transcript Dr. Harkins-Exercise Induced Asthma (new window)

Asthma
Michelle Harkins, MD
University of New Mexico
Pulmonary and Critical Care
Project Echo
Asthma and School Absences
• Asthma is one of the leading causes of
school absenteeism.
• In 2003, an estimated 12.8 million school
days were missed due to asthma among the
more than 4 million children who reported at
least one asthma attack in the preceding
year.
• 39% reported receiving an asthma
management plan
Akinbami LJ. The State of Childhood Asthma (pdf 365K), United States, 1980-2005. Advance data from Vital and Health
Statistics: no 381, Revised December 29, 2006. Hyattsville, MD: National Center for Health Statistics, 2006
Asthma in New Mexico
• 204,292 adults have had an asthma dx
– 68.8K under age 17
• # of days missed by NM School children for
asthma?
• Estimated cost of treating asthma in those
under 18 is $3.2 billion per year
(Weiss KB, Sullivan SD, Lytle SD)
• 30-40 deaths/year from asthma
– Mortality decreased from 3.1/100,000 in 1993 to
1.5/100,000 in 2004
– >65 years at greatest risk
•
Dept. of Health Statistics, 2007, BRFSS
Rates per 10,000 pop.
Asthma Hospitalization Rates by Age Group: US (2006) and
NM, Southeastern NM, and Lea County (2006-2008)
140.0
120.0
100.0
77.9
80.0
60.0
40.0
US
NM
49.5
SE NM
23.920.1
20.0
12.4
7.1 4.8
5.1
16.2
8.6
14.5
8.5
23.7
18.5
13.5
0.0
< 15
15-44
45-64
Note US rates are 2006; all other rates are 2006-2008 average.
SOURCE: Nationa Health Statistics Report, No. 5, July 30, 2008; NMHPC.
65+
Lea Co.
8.2
Asthma Hospitalization Rates (Age<15), 2006-2008
Rates per 10,000 pop.
80.0
60.0
40.0
49.5
20.0
0.0
20.1
17.3
13.2
16.5
New Mexico
NW
NE
Bern. Co.
SOURCE: NMHPC.
12.3
SE
SW
Asthma Hospitalization Rates (Age<15), New Mexico 2006-2008
42.9*
15.5*
7.9*
9.0*
27.7
10.1*
38.2
56.5
22.5
14.9*
16.8*
13.6*
33.1
23.3
41.5
46.7
14.2
13.2
49.2
26.8
23.4
10.3
9.5
35.1 41.8
11.1
13.7
0.0*
0.0*
39.2
15.3
12.0
16.5
14.9
14.9
9.1*
6.6*
21.8
18.2 22.2
13.3
17.7*
19.4
62.2
25.5
7.6*
28.7*
19.0*
17.8*
135.6
8.0*
4.5*
22.7*
20.6*
17.7*
6.2*
14.8*
14.8*
5.8*
13.9*
104.2
9.2*
13.7*
37.0
STATE RATE: 20.1
63.3
64.7
103.2
0.0 – 10.1
42.9
50.9
144.0
10.2 – 14.2
14.3 – 23.3
15.1
35.4
63.9
69.1
6.3*
10.5*
11.6
11.3*
60.4
11.5
11.7
37.9
23.4 – 77.9
10.9
11.4
80.1
77.9
118.2
76.3
23.7
46.5
95.3
Rates per 10,000 population.
75.4
26.1
24.5
15.6*
26.2*
24.0*
* Rates based of fewer than 20 cases should be interpreted with caution.
SOURCE: NMHPC.
What is Asthma?
• A chronic inflammatory disease of the
airways
– The majority of asthma diagnosed in childhood
• Common Symptoms:
– Cough-may be only at night
– Wheezing
– Chest Tightness
– Shortness of breath
– Mucus (phlegm production)
Features of Asthma
• Intermittent wheezing, chest tightness,
cough—times when there are no symptoms
• Bronchial hyperresponsiveness-”twitchy”
airways
• Airway inflammation
• Airway obstruction - initially reversible
– gradual decline in lung function
– Peak Flow variability
All that wheezes is not asthma...
• Bronchiolitis: RSV
• Aspiration (micro versus foreign body)
• vocal cord dysfunction, laryngeal
dysfunction
– Competitive athletes
– 35% of “severe asthma” referred to specialty
clinics
• CF
• Tracheal malacia
Vocal Cord Dysfunction
•
•
•
•
•
•
VCD can mimic asthma, but it is a distinct disorder
VCD may coexist with asthma
Asthma medications typically do little, if anything, to
relieve VCD symptoms
Variable flattening of the inspiratory flow volume
loop on spirometry is strongly suggestive of VCD
Diagnosis of VCD is from indirect or direct vocal cord
visualization during an episode, during which
abnormal adduction can be documented
VCD should be considered in patients with difficultto-treat, atypical asthma and in elite athletes who
have exercise related breathlessness unresponsive
to asthma medication
Guidelines for the Diagnosis and Management of Asthma
NHLBI NAEPP EPR 3
November, 2007
Spirometry and Flow Volume
Loops
Normal
Reversible airflow
obstruction
VCD possible
FEV1
4.36 (100%)
2.27  2.71 (16%)
3.65 (99%)
FVC
5.04 (108%)
3.20  3.58 (11%)
3.71 (96%)
FEV1 / FVC
.86
.71  .76 (6%)
FEF25-75
4.77 (108%)
1.63  2.13 (23%)
6.15 (155%)
FEF50 / FIF50
0.84
0.38  0.30
4.33
.98
Pathophysiology of Asthma
Epithelial Damage in Asthma
Normal
Jeffery P. In: Asthma, Academic Press 1998.
Asthmatic
Asthma Pathophysiology
Smooth Muscle
Dysfunction
•
•
•
•
Bronchoconstriction
Bronchial hyperreactivity
Hypertrophy/hyperplasia
Inflammatory mediator
release
Airway
Inflammation
• Inflammatory cell
infiltration/activation
• Mucosal edema
• Cellular proliferation
• Epithelial damage
• Basement
membrane
thickening
Symptoms/Exacerbations
Exercise Induced Asthma
• Bronchospasm caused by activity
• Distinct from environmental induced
asthma
– Does not cause swelling, inflammation or
mucous production
• Can be avoided by giving medication prior
to activity and by warming up and cooling
down
Exercise Induced Asthma
• Bronchospasm caused by activity
– Some activity more likely than others to trigger
it
• Cold environment: skiing, ice hockey
• Heavy exertion: Soccer, long distance running
• Exercising when you have a viral cold
Exercise Induced Asthma
• Symptoms include
– Coughing
– Wheezing
– Chest tightness
• Symptoms may begin during activity and
peak in severity 10-20 minutes after stopping
• Can spontaneously resolve 20-30 minutes
after its onset
Epidemiology
• Prevalence 7-20% of the general population
• 80% of patients with asthma have some
degree of EIB
• Exercise is not a risk factor for asthma, rather
a trigger
• ?Exercise may help prevent onset of asthma
in children
– Decrease in physical activity may play a role in
increased in asthma prevalence
• JACI 2005 Lucas SR, Platts-Mills TA
Pathogenesis
• Minute ventilation rises w exercise (Vt x RR)
• Large volume of relatively cool, dry air
inhaled during vigorous activity changes
airway physiology.
• Inflammatory mediators released
– Leukotrienes LTC4 and LTD4, histamine, IL-8
• Th2-lymphocytes are activated: express
CD23
• Eosinophils activated and increased in most
Clinical Manifestations
• Patients with EIB have initial bronchodilation
during 6-8 minutes of exercise
• Followed by bronchoconstriction starting 3
minutes AFTER exercise, peak 10-15 min.
• Resolves after 30-60 minutes
• Refractory period where repeat exercise
causes less bronchoconstriction
• Hoarseness or stridor may suggest VCD
instead.
Time Course of Exercise Induced
Bronchoconstriction
Diagnosis
• Clinical history of asthma and typical asthma
symptoms after exercise, no testing needed
• Exercise challenge test: cycle or treadmill for
4-8 minutes until HR 85% of predicted
maximum
• Fall in FEV1 by 15% is diagnostic
– Baseline, then 3, 5, 10, 15 and 30 minutes post
exercise
• Peak Flows pre and post less accurate but
have been used
Dyspnea with Exercise
• If no history of asthma and pre-medication
doesn’t help think about other diagnoses:
• VCD or central airway obstruction
• Deconditioning
• Tracheal malacia
• Cardiac causes
• Other lung disease
Management
• Increasing fitness: decreases minute
•
ventilation needs with exercise
Less severe if inspired air is warmer, more
humid (Evidence Class C)
– Scarf or mask if cold weather
– Warm-up period before exercise
• Good asthma control: EIB more frequent in
patients with poorly controlled disease (Class A)
– Check for asthma control
– Treating appropriately will reduce frequency and
severity of EIB
Pharmacotherapy
• Inhaled Beta agonists
– Short and long acting
• Cromoglycates
• Inhaled Steroids
• Leukotriene modifying agents
• Avoid oral agents: theophylline or beta
agonists
Non-pharmacotherapy
• Fish oil supplementation was protective for
EIB in elite athletes
• Diet rich in Omega-3 fatty acids
– Randomized
double blind crossover study of 16
patients tx for 3 weeks with fish oil vs. placebo
• 3.2 gm eicosapentaenoic acid, 2gm docohexaenoic acid
– Pre and post exercise measurements of lung
function, induced sputum, leukotrienes and
cytokines
– Fish oil diet decreased EIB, Sx and improved lung
function, less bronchodilators needed
– Mickleborough et al, Chest 2006
Beta agonists
• 2 puffs albuterol HFA 10 minutes prior
• More severe asthma may need higher dosing
• LABAs: Salmeterol or Formoterol have been
used but not advised as daily monotherapy
for EIB.
• Intermittant beta agonist is preferred and
more effective and will prevent EIB >80%.
• Regularly scheduled albuterol INCREASES
EIB and has decreased response to therapy.
–
Hancox Am JRRCM 2002,; Inman Am JRCCM 1996
Cromoglycates
• Prophylactic cromolyn 2-4 puffs 15-20
minutes prior
• Mast cell stabilizer
• In high performance athletes or exercise
under extreme conditions: combining 4 puffs
with 4 puffs beta agonists likely more
effective than either drug alone.
Inhaled Steroids
• Improves hyperresponsiveness over weeks
to months and will help in the long run if poor
asthma control is the cause of EIB.
• Important to assess for asthma symptoms
outside of exercise when controller therapy is
warranted.
Anti-leukotriene agents
• Decreases urinary leukotrienes after exercise
• Protection from EIB by 2 hours after a dose
•
•
•
•
and post exercise recovery is accelerated.
Not effective in all patients
Probably better than long acting beta
agonists over time but not better than short
acting.
Decreases EIB by 50% compared to placebo
May be beneficial for those with
unpredictable exercise patterns that cause
symptoms.
Break through symptoms
• 2-4 puffs of inhaled beta-agonists
• Cromolyn not effective
Competitive Athletes
• Need for disclosure of medications to
organization
– File Therapeutic Use Exception during
competitions
• World Anti-Doping Agency lists beta
agonists, inhaled steroids as prohibited
– Reference Line is 1–800–233–0393
Schools
• Teachers and coaches should be notified of
children with asthma
• Students are encouraged to be active
• May need to take medications prior to activity
Prevention of Exercise Induced
Asthma
• Use bronchodilator 10-15 minutes before
onset of activity
• Do warm-up/cool down exercises
• Check ozone/allergy warnings
• Never encourage a child to “tough it out”
The Four Components of Asthma
Management
• Measures of assessment and monitoring
– Objective tests, physical exam, history
– Severity and control of asthma
• Education for a partnership in asthma care
• Control of environmental factors and
comorbid conditions that affect asthma
• Pharmacologic therapy
Persistent Asthma: Daily Medication
Intermittent
Asthma
Consult with asthma specialist if step 4 care or higher is required.
Consider consultation at step 3.
Step 6
Step 5
≥ 12 years old
Step 4
Step 2
Preferred:
Step 1
Low-dose ICS
Preferred:
Alternative:
SABA PRN
Cromolyn,
Nedocromil,
LTRA, or
Theophylline
Step 3
Preferred:
Preferred:
Medium-dose
ICS + LABA
Medium-dose
ICS
OR
Low-dose
ICS + LABA
Alternative:
Low-dose ICS +
either LTRA,
Theophylline, or
Zileuton
Alternative:
Medium-dose
ICS + either
LTRA,
Theophylline, or
Zileuton
Preferred:
High-dose
ICS + LABA
Preferred:
High-dose
ICS + LABA +
oral
corticosteroid
AND
Consider
Omalizumab for
patients who
have allergies
AND
Consider
Omalizumab for
patients who
have allergies
Patient Education and Environmental Control at Each Step
Steps 2-4: Consider SQ allergen immunotherapy for allergic patients
Quick-Relief Medication for All Patients
• SABA as needed for symptoms. Intensity of treatment depends on severity of symptoms: up to 3 treatments at 20-minute intervals
as needed. Short course of systemic oral corticosteroids may be needed.
• Use of beta2-agonist >2 days a week for symptom control (not prevention of EIB) indicates inadequate control and the need to
step up treatment.
Step up if
needed
(first, check
adherence,
environmental
control, and
comorbid
conditions)
Assess
control
Step down if
possible
(and asthma is
well controlled
at least
3 months)
Pharmacotherapy in Asthma
•
•
•
•
•
•
•
Short acting beta-2 agonists
– Albuterol, levalbuterol
Long acting beta-2 agonists
– Salmeterol, Formoterol
Inhaled corticosteroids—fluticasone, budesonide,
mometasone, ciclesonide, beclomethasone,
flunisolide, triamcinolone
Leukotriene modifiers
Combination inhalers
– ICS/LABA
Theophylline
Oral steroids for exacerbations
Barnes et.al 1998 Asthma Basic Mechanisms and Clinical Management
Not all Spacers are created equal
One Way Valves
Action Plans
• All children with asthma should have an
action plan to guide therapy
• Can be symptom based or PF based
• Green 80% of personal best Peak Flow
• Yellow 50-80% of best
• Red zones <50% of best. GET HELP!
Asthma Management:
Patient Education the Key
• KEY EDUCATIONAL MESSAGES: TEACH
AND REINFORCE AT EVERY
OPPORTUNITY!
• Teach the Basic Facts About Asthma
– The contrast between airways of a person with
and without asthma
– The role of inflammation
– What happens to the airways during an asthma
attack
Asthma Management:
Patient Education the Key
•
Role of Medications: Understanding the
Difference Between:
– Long-term control medications: prevent symptoms,
often by reducing inflammation. Must be taken daily. Do
not expect them to give quick relief.
– Quick-relief medications: SABAs relax airway muscles to
provide prompt relief of symptoms. Do not expect them
to provide long-term asthma control. Using SABA >2
days a week indicates the need for starting or increasing
long term control medications.
Asthma Management:
Patient Education the Key
• Teach Patient Skills
– Taking medications correctly
– Inhaler technique (demonstrate to the patient
and have the patient return the demonstration).
– Use of devices, as prescribed (e.g., valved
holding chamber (VHC) or spacer, nebulizer).
– Identifying and avoiding environmental
exposures that worsen the patient’s asthma;
e.g., allergens, irritants, tobacco smoke.
Asthma Management:
Patient Education the Key
• Self-monitoring
– Assess level of asthma control.
– Monitor symptoms and, if prescribed, PEF
measures.
– Recognize early signs and symptoms of
worsening asthma. Use a written asthma
action plan to know when and how to:
• Take daily actions to control asthma.
• Adjust medication in response to signs of worsening
•
asthma.
Seek medical care as appropriate.
Goals for Asthma ECHO clinic
•
•
•
•
Use best practices to implement the National
Guidelines for asthma management
Enhance the care of asthmatics throughout the state
by working with a variety of healthcare proffesionals.
– Physicians, NPs, PAs, school nurses and SBHC
– RTs, Pharmacists, CHWs, DOH
Have a certified asthma educator in every county.
Develop asthma centers of excellence
Current Asthma ECHO clinic
• Short didactic teaching on relevant topics:
participant guided.
– Visual demonstrations of asthma medications/devices,
management of exacerbation, other factors impacting
control
• Case presentations
– Written recommendations sent back to provider
•
Clinics are 2nd and 4th Fridays 12-1.
–
–
–
–
The dial-in number is:
Toll Free Number: 1.800.617.4268 and when asked, enter the
PIN # 81465589#
The participant will be asked to state their name and hit the #
key at which time they will be joined in.
For Video Participants: 64.234.191.##2000
Websites for further info
• www.cdc.gov
• www.nhlbi.nih.gov/guidelines/asthma
• http://echo.unm.edu