asthma and allergies

Asthma and Allergies

Pamela Amelung, MDMini-Med School Fall 2006University of Maryland School of Medicine

What is asthma? Asthma facts and statistics Who is most at risk to get asthma? Symptoms and triggers, including allergies Management of asthma How to avoid triggers and attacks

Topics Covered

Chronic inflammatory disorder of the medium and small airways.

These airways are hypersensitive to certain “triggers” in the environment.

Intermittent and recurrent episodes of...– Wheezing– Shortness of breath – Chest tightness– Cough - night, early morning

Usually reversible

Asthma cannot be cured but its symptoms can be controlled with proper environmental changes and medication.

What is Asthma ?

About 17 million Americans have asthma

Most common chronic childhood disease, affecting about 5 million children (6% of children under 18)

14 people die each day from asthma

Nearly 2 million emergency room visits each year

The facts about Asthma

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2

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8

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14

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1993

1998

How many people have Asthma

? The number of

Americans diagnosed with asthma has risen.– Self-reported

prevalence increased 75%

Close to 21 million Americans have been diagnosed with asthma in their lifetime.

*MMWR December 04, 1998 / 47(47);1022-1025

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The cost of Asthma ! Asthma costs

billions of dollars each year and the cost is rising.

The estimated annual cost of asthma in 2000 was $14.5 billion.

* www.cdc.gov

1990 2000

$6.2 billion

$ 14.5 billion

The cost of Asthma ! 3 million lost

work days

10 million lost school days each year from asthma

The cost of Asthma ! Deaths from

asthma have increased more than 50% in the past 20 years, and have increased more than 75% in children under 19

*CDC MMWR April 24, 1998 / 47(SS-1);1-28

Race and asthma

Mortality

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Asthma Mortality:Female vs. Male

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Risk factors for

Asthma Allergy / Atopy Family history of

asthma/allergy Perinatal exposure to

tobacco smoke Viral respiratory

infections Low birth weight Male gender - pre-

adolescence Low-income, urban

residents Obesity

Classification of Asthma Intermittent -

– Asthmatics who have symptoms that occur with a cold from time to time.

– They often grow out of the disease.

Persistent -– Asthmatics having symptoms at least twice

a week during the day and twice a month during the night

– These asthmatics are further classified as mild, moderate, or severe.

Coughing

Wheezing

Chest tightness

Shortness of breath

Symptoms of Asthma

Asthma Triggers For people with asthma,

exposure to certain substances they are sensitive to can lead to an asthma attack or exacerbation.

These substances are known as triggers.

Not all people with asthma have the same triggers that will cause an asthma attack.

Indoor air Triggers

Environmental tobacco smoke (ETS)

Cockroaches Dust mites Animal dander Mold, mildew Strong scented products

(perfumes, scented cleaners)

All of the common asthma triggers are found indoors

Americans spend about 90% time indoors

Reducing exposure to indoor allergens and irritants can reduce asthma symptoms

Prevention is an important asthma management tool

Why indoor air is Important

Contains more than 4,000 substances (over 40 are carcinogenic)

Is particularly harmful to young children

Can trigger asthma attacks and cause young children to develop asthma

Secondhand Smoke

Found in most homes

Live in soft bedding

Feed on skin flakes

Mites and mite droppings can be asthma triggers

Most common asthma trigger in adults and kids

Dust Mites

Skin flakes, urine and saliva of warm blooded animals can be asthma triggers.

Triggers can remain in the home for several months after a pet is removed, even with cleaning.

Pets

Can be found almost anywhere.

Key to mold control is moisture control.

Clean up the mold and get rid of excess water or moisture, this also helps reduce other triggers, such as dust mites and cockroaches.

Molds

Droppings or body parts can be asthma triggers.

Cockroaches likely contribute significantly to asthma problems in inner city area.

Asthmatic children allergic to cockroaches are three times more likely to be hospitalized if exposed in the home.

Cockroaches and other Pests

Outdoor air Triggers

Ozone

Particulate matter

Sulfur dioxide

Nitrogen dioxide - vehicle exhaust

Outdoor pollens and mold

Additional Triggers Viral upper

respiratory infections Exercise Aggravating

conditions - gastric reflux, sinusitis, rhinitis

Diet, medication Cold air Changes in weather Menstrual cycle,

pregnancy

What causes an Asthma Attack ?

An allergic reaction to triggers or exposures

Airways swell and fill with mucus and secretions

The muscles around the airways contract and spasm

Airways can collapse, causing classic symptoms, even death

Indications of a severe

Attack Breathless at

rest Hunched forward Talking in words

rather than sentences

Agitated Peak flow rate is

less than 50% of normal

Management of

AsthmaAsthma is one condition that, when treated

with timely and effective regular outpatient care,

prevents hospitalization and ED visits.

Consult with a physician to develop an asthma management plan, which includes:

Medication Education: identification of asthma

triggers & ways to reduce/avoid exposure to your asthma triggers

Peak flow monitoring Emergency plan

Managing Asthma

Goals of asthma

Management Control chronic asthma symptoms and asthma

attacks during the day and night– no sleep disruption due to asthma– no missed school or work because of asthma– no or minimal need for emergency care or

hospitalizations Avoid attacks or exacerbations Maintaining normal activity levels, including

exercise and other daily activities Having normal or near-normal lung function Avoid side-effects of medications Prevent asthma mortality

Choose not to smoke in your home or car and do not allow

others to do so either.

Avoiding secondhand

Smoke

Wash sheets and blankets once a week in hot water

Choose washable stuffed toys-- keep stuffed toys off beds

Cover mattresses and pillows

Vacuum often (when asthmatic is not present)

Maintain low indoor humidity, ideally between 30-50% 

Avoiding dust Mites

Consider keeping pets outdoors or even finding a new home for your pets, if necessary.

Keep pets out of the bedroom at all times.

Keep pets away from fabric-covered furniture, carpets, and stuffed toys.

Avoiding pet Triggers

Wash mold off hard surfaces and dry completely, absorbent materials (ceiling tiles and carpet) may need to be replaced.

Use exhaust fans or open windows in kitchens and bathrooms when showering, cooking, or using the dishwasher.

Maintain low indoor humidity (between 30-50% relative humidity).

Fix leaky plumbing or other sources of water. Keep drip pans in your air conditioner,

refrigerator, and dehumidifier clean and dry Clean bathrooms frequently.

Avoiding mold Triggers

Pest Avoidance

Free your home of places for pests to hide and sources of food and water

Regular, careful cleaning - kitchen Daily trash removal Store food in airtight containers Extermination - baits, gels (not

sprays)

Prevent outdoor

Triggers Ozone - advisories, stay indoors Pollens and Molds (if allergic)

– Close windows, doors– Use air conditioners, clean filters

regularly– Dry clothes indoors– Avoid raking leaves, gardening– Outside - less breezy, after gentle

rain

Peak expiratory flow (PEF) Meters

Allows the Allows the patient to patient to assess the assess the status of his status of his or her or her asthmaasthma

Peak flow Chart

People with People with moderate or moderate or severe asthma severe asthma should take should take readingsreadings—— Every morning Every morning and eveningand evening After an After an exacerbationexacerbation Before inhaling Before inhaling certain certain

medicationsmedicationsSource: “What You and Your Family Can Do About Asthma” by the Global Initiative For Asthma Source: “What You and Your Family Can Do About Asthma” by the Global Initiative For Asthma Created and funded by NIH/NHLBICreated and funded by NIH/NHLBI

Management of Asthma

Quick-relief medications used to treat asthma attacks and acute symptoms

“Relievers”Long-term control medications reduce the airway inflammation that causes these symptoms

“Controllers”

Asthma Medications Quick-relief medications

– Short-acting bronchodilators •Relax smooth muscle around the airways

Long-term Medications– Steroids

• Inhaled, tablets•Anti-inflammatory

– Long acting bronchodilators•Relax smooth muscle

– Leukotriene inhibitors•Anti-inflammatory

Asthma action Plan

National Heart, Lung, and Blood Institute

Asthma is Increasing

Why the increase? Increased recognition, diagnosis-shifting Environmental allergens - indoor, outdoor

– Energy-efficient buildings, carpet Exposure to mother’s tobacco smoke Psychosocial and socioeconomic factors

– More time indoors– Overcrowding– Access to care

“Hygiene

Hypothesis”

Are we too clean ? Immune Response

– Th1 •Responds to harmless bacteria, dirt, animal droppings after birth

•Not activated in sterile birth environment

•Subdues the more hyperactive Th2– Th2

•Not as effective as Th1•Fight allergens, cause allergies

T0

T2T1

“Hygiene

Hypothesis” Are we too clean ? Less allergies and asthma:

– 1990 East vs. West Germany– Farm vs. city children– Daycare before 6 months of age vs.

later – Older siblings vs. none

Failure to develop balanced immune system– Detergents/chlorine, antibiotics,

vaccines, antibacterial soaps

Healthy people 2010Objectives

Reduce asthma deaths Reduce hospitalizations for asthma Reduce hospital ED visits for asthma Reduce activity limitations - reduce #

of school/work days missed Increase proportion who receive formal

patient education Increase proportion who receive

appropriate asthma care Establish in 25 states a surveillance

system for tracking asthma

http://www.health.gov/healthypeople

Conclusions Asthma affects 5-10% of the population

and the prevalence is rising in developed countries.

Allergies often play a key role in asthma and act as triggers for asthma symptoms.

Asthma can not be cured but can usually be well controlled in most people.

Controlling asthma involves patient education, lung function monitoring, avoidance of triggers, and in many, medications.