Asthma: Current Concepts in Diagnosis and ManagementChristie F. Michael, MD

Assistant Professor

University of Tennessee, Memphis

Goals of Talk

Scope of asthmaDefinition/diagnosisNHLBI guidelines 2007Asthma in pregnancyOmalizumab

Asthma in Adults

14.7 million in US >10million office visits/yr ~1.9million ED visits/yr 466,000 hospitalizations/yr

Asthma Mortality

Asthma deaths: >5000 each year (1998,USA)

Asthma death in children 36% severe persistent 31% moderate persistent 33% mild persistent

The Good News

Mortality on decline despite increasing incidence

Most asthmatics can lead normal, active life with proper treatment

Asthma Definition

Obstructive lung disease with key features including partial reversibility, airway hyper-responsiveness and airway modeling

Davies, et al. Airway remodeling in asthma: new insights. JACI 2003; 111:215-25

Asthma: Expanding Definition

“A chronic inflammatory disorder of the airways in which many cells and cellular elements play a role…”

1.“Reversibility incomplete in some patients..”

2. Anti-inflammatory tx fails to prevent dz progression.

Airway Remodeling

Sub-basement fibrosis Mucus hypersecretion Epithelial injury Smooth muscle hypertrophy Angiogenesis

Not All That Wheezes Is Asthma…

-Foreign body- Upper airway diseases - Enlarged lymph nodes or tumor- Vocal cord dysfunction - Aspiration/GERD - COPD- CHF- PE- Drug reaction/side effect

Asthma Does Not Always Wheeze…

Chronic or nocturnal cough with awakenings

Exercise induced symptoms Chest tightness Viral induced symptoms

Asthma Diagnosis

Lower airway obstruction Variation in the magnitude of obstruction Recurrence of obstruction on more than

one occasion PFT’s/ peak flow variability Exclusion of alternative diagnoses

Diagnosis of Asthma

PFTs - FEV1 <80%

- Fev1/FVC

Ratio <65%

- >12%(200ml)

Reversibility in

FEV1 after B2

Agonist

Diagnosis of Asthma

Methacholine challenge:

Peak expiratory flow rate (PEFR):

Ht (cm) X 5.25-425

Gene by Environment

RSV in pediatrics Smoking/ smoke exposure Atopy Many others…

Link Between Asthma/Atopy:“One Airway, One Disease”

~80% asthmatics with allergic rhinitis 40% AR pts with asthma Of asymptomatic AR pts- up to 40% with

AHR Nasal allergen challenge increases AHR tx AR lowers asthma sx’s and related

costs

Guidelines for Asthma Diagnosis and Management

ASSESSMENT and MONITORING CONTRIBUTING FACTORS PATIENT EDUCATION PHARMACOTHERAPY

Asthma Severity Classification

Intrinsic intensity of dz process Used as the basis for selection of

therapy Incorporates subjective and objective

parameters Must apply with clinical judgement

Impairment AND Risk

Domains of both assessment and control

Current symptoms Future risk Objective and subjective measures

Impairment

Quality of life Missed school or work Surveys (ACT, ACQ..) Lung functions

Risk

Hospital stays/ICU ED visits Oral steroid bursts Lung function (FEV1, FEV1/FVC) Other biomarkers not proven (FeNO,

serum IgE, bld/sputum eos)

Assess Control

Once long-term control therapy initiated Responsiveness- the ease with which

control achieved Continue to assess impairment and risk

Guidelines for Asthma Diagnosis and Management

ASSESSMENT and MONITORING CONTRIBUTING FACTORS PATIENT EDUCATION PHARMACOTHERAPY

Precipitating Factors

Viral URIs Inhalant allergens- grasses, trees,

molds, pets, dust/dust mite, feather, cockroach

Food allergens- soy, wheat, milk, nuts, eggs

Irritant triggers- strong odors, smoke, cold air

Weather changes

Comorbid Conditions

Sinusitis Rhinitis Gastroesophageal reflux ABPA Vocal cord dysfunction OSA

Recognizing High-risk Asthmatics

Beta2-agonist over-use Disregard of symptoms Psychosocial factors Previous respiratory arrest or ICU admit

Asthma in Pregnancy

1/3 patients better1/3 stay the same1/3 worsen

Acute Treatment of Asthma

2 Agonists- PO, IV (albuterol, terbutaline) Anticholinergics- Ipatropium (Atrovent) Steroids- PO, IV (solumedrol, prednisone) Methylxanthines- PO, IV (Aminophylline,

Theophylline) Heliox (60/40) Magnesium Sulfate Intubation

Treatment of Asthma-Controller Therapy Inhaled Corticosteroids- gold standard Long-Acting B2 Agonists Leukotriene Modifiers Mast Cell Stabilizers Theophylline Omalizumab (Xolair) Immunotherapy

Inhaled corticosteroids

Preferred treatment for all classes of persistent asthma

Maximize benefit/ minimize risks combination therapies to minimize doses

(leukotriene modifiers, long acting beta2- agonists…)

Medications in Pregnancy

NASAL Pseudoephedrine (avoid in 1st trimester) Oxymetazoline nasal spray (3-5 days) Nasal steroids budesonide* beclomethasone Nasal saline irrigation Antihistamines chlorpheniramine cetirizine (after 1st trimester) loratadine (after 1st trimester)

Medications in Pregnancy

ASTHMA theophylline inhaled beta-agonists cromolyn prednisone (when indicated) inhaled steroids budesonide* beclomethasone

Anti- IgE Therapy: Omalizumab

XOLAIR multicenter, randomized, DBPCT, phase

III Anti-IgE reduces asthma exacerbations,

ED visits and hospitalization rates Adjunctive tx in poorly controlled

asthmatics and pt in need of IT but unable to tolerate due to severity of asthma

Anti-IgE: Qualifying for tx

Documented allergy to perennial allergen

Serum total IgE 30-700 Asthma

Referral Guidelines

Difficulty achieving/mx control Step 4 or higher Immunotherapy Omalizumab ICU stay