Asthma

Definition

Asthma is a chronic inflammatory disease of the respiratory system that makes it hard to breath. The disease is an over-responsiveness of the respiratory system to stimulating factors. Symptoms include repeated, temporary episodes of constriction and inflammation of the airways and lungs, along with excess mucous production. Asthma causes wheezing, coughing, and shortness of breath. Asthma attacks are characterized by severe difficulty breathing, especially when exhaling.

Description

Asthma is a chronic disease that affects the network of air passages of the respiratory system. People with asthma may experience symptoms ranging from mild discomfort to life-threatening attacks that require immediate emergency treatment. The respiratory system is made up of bronchial tubes (airways) and the lungs. Asthma involves inflammation of the bronchial tubes and lining of the lungs. The inflammation causes the airways to be overly sensitive to irritating factors,

which cause constriction and obstruction to the passageway that brings air to the lungs.

People with asthma produce excess amounts of mucous in the respiratory tract. Mucous is a normal component of respiratory function that aids in carrying irritating particles up and out of the respiratory system to be coughed up from the body. People with asthma produce excessive, abnormally thick mucous that interferes with breathing and contributes to the problem.

Severe asthma attacks can be fatal. Persistent or chronic inflammation of the airways can cause permanent damage. Severe attacks can also reduce lung function so that breathing becomes less efficient even outside of asthma attacks. People with asthma may experience chronic wheezing, coughing, shortness of breath, and tightness in the chest. Medication and careful management of the disease is often necessary for maintaining normal function. Chronic asthma has both a genetic and an environmental component. Research shows that some people inherit a strong genetic predisposition for asthma that can be triggered by a variety of environmental factors. These triggering factors include repeated exposure to lung irritants, such as dust mites, pet hair, and tobacco smoke. These types of stimuli are called allergens, which are particles that trigger an allergic response. Asthma may also be induced by exercise , especially in cold climates where the respiratory system has to work harder to warm and moisten the air that is breathed in. Some people with asthma only experience symptoms during viral infections. Asthma can be brought on by emotional stress . Both physical and psychological factors can bring on an asthma attack. Severe attacks that are left untreated can become fatal. A person with asthma may not have any symptoms between attacks.

Demographics

Asthma is more common in children than adults. In adults, it is more common in women than men. Adult females have a 30% higher prevalence of asthma than adult males. In the United States, nearly 11% of people 65 and older have asthma, compared to 8% in the United Kingdom, 6% in France, and up to 8% in Canada. Within ethnic groups, non-Hispanic blacks have more asthma attacks and are more likely to be hospitalized and die from asthma than non Hispanic whites. Asthma is distinct from, but closely linked to, allergies . Most, but not all, people with asthma have allergies.

Asthma has been described as the fastest-growing chronic disease and a worldwide epidemic. According to Global Initiative for Asthma (GINA), an asthma research and education program, asthma accounts for about one in every 250 deaths worldwide. Many of the deaths are believed to be preventable and are caused by poor medical care. GINA estimates that there are over three million people with asthma worldwide. In most countries, asthma cases are increasing 20–50% every decade. The United States is one of the top countries for prevalence of asthma, along with England, Australia, parts of South America, and Canada.

Causes and symptoms

Causes

People who have a family history of asthma are more likely to develop the condition than people with no family history of asthma. Elderly persons often have more severe asthma than younger people and may be more likely to require urgent medical treatment and hospital admission. In the elderly, the most common causes of late-onset asthma are sensitivity to cat allergen and other allergies, especially dust mites. They are also more likely than younger persons to develop asthma associated with the use of certain medications, including aspirin , nonsteroidal antiinflammatory drugs (NSAIDs), and adrenergic-blocking agents used to treat some types of heart conditions and high blood pressure .

Exercise is a common trigger for asthma in about 80% of asthmatic individuals. Some people with asthma have exercise-induced symptoms brought on by brisk activity such as running, especially during cold weather. Pretreatment medications, such as short-acting bronchodilators , quickly widen air passages and help prevent the onset of asthma during physical activity. Activities that allow for frequent breaks rather than prolonged endurance are most suitable. Asthma does not have to be a barrier to participating in athletic activities. Many Senior Olympic athletes have exercise-induced asthma that is controlled by medication. Emotional stress may also trigger asthmatic symptoms, such as coughing or wheezing from prolonged crying or laughing.

Every asthma patient is unique. Because there are so many environmental conditions that affect individuals with a genetic predisposition for asthma, it is often difficult to pinpoint the primary cause of the disease in individual cases.

Symptoms

There are several common symptoms of asthma. The frequency and intensity depends on each individual person and attack. The symptoms most often experienced include:

• coughing that is worse at night or early in the morning, making sleep difficult
• wheezing; a whistling or squeaky sound when breathing, especially during a cold, flu, or other illness
• tightness in the chest, as if it is being compressed
• shortness of breath and the feeling of breathlessness
• difficulty getting enough air in or out of the lungs, especially when exhaling
• fast breathing; if airflow to the lungs is inadequate, a lack of sufficient oxygen to the tissues causes the body to breathe faster in an attempt to get more oxygen

A person with asthma may have any combination of symptoms, which can vary from one asthma attack to another. Symptoms may exhibit a range of severity, from mildly irritating to life-threatening. Symptoms occur with varying frequency from once every few months to every day. Asthma classifications are based on symptom levels in the absence of medication.

• Mild intermittent asthma—Defined as symptoms of wheezing, coughing, or breathing difficulty twice a week or less, with night symptoms twice a month or less.
• Mild persistent asthma—Defined as symptoms of wheezing, coughing, or breathing difficulty once a day or less, but more than twice a week. Symptoms occur at night more than twice a month.
• Moderate persistent asthma—Defined as daily symptoms that require daily medication. Symptoms at night occur more than once a week. Symptoms may be severe enough to interfere with normal physical activity.
• Severe asthma—Described as ongoing, persistent symptoms with more serious asthma attacks. Symptoms may occur throughout the day, with night symptoms occurring often. In severe asthma, physical activity is likely to be limited.

People with any degree of asthma may have severe asthma attacks. However, with appropriate treatment and avoidance of asthma stimulators, most people with asthma can achieve a general condition of minimal or no symptoms. People with asthma are encouraged to recognize their own specific asthma stimulators and avoid them, and to recognize their specific early warning signs that signal the start of an attack. The first signs of a mild or moderate attack may be a slight tightening of the chest, coughing or wheezing, and spitting up mucous. Severe attacks can bring on a feeling of extreme tightening of the neck and chest, making breathing increasingly difficult. People with asthma may struggle to speak or breathe. In advanced stages of severe attacks, lips and fingernails may take on a grayish or bluish tinge, indicating declining oxygen levels in the blood. Such attacks can be fatal in the absence of prompt medical attention. Asthma symptoms are usually reversible with medication.

Diagnosis

Asthma is often difficult to diagnose in the elderly due to misconceptions about its prevalence and because older patients often have other conditions that mimic asthma symptoms, such as heart failure and chronic obstructive pulmonary disease (COPD). At least half of elderly people with asthma were recently diagnosed, according to the Canadian Medical Association.

The first stage of asthma diagnosis is to obtain a history of asthma symptoms. These symptoms include periods of coughing, wheezing, shortness of breath, or chest tightness that come on suddenly in response to specific stimulants or time periods. A history of head colds that evolve into chest congestion or take more than 10 days to recover from is pertinent. Family history of asthma or allergies may also be part of the diagnosis.

A physical exam may reveal wheezing in the chest that can be heard with a stethoscope. A device called a spirometer may be used to check the function of the airways. This test measures the volume of air and the speed with which air can be blown out of the lungs after a deep breath. If the airways are narrowed from inflammation and the muscles around the airways tightening up from asthma, the results will be lower than normal. If spirometry results are normal but asthma symptoms are present, other tests are performed. A bronchial challenge test involves inhalation of a substance such as methacholine, which causes narrowing of the airways in asthma. The effect is measured by spirometry to determine if asthma is present.

Treatment

There is no cure for asthma but it can be controlled with proper treatment. In many respects, asthma in the elderly is treated the same as in younger people. Asthma in senior populations is treated by avoiding factors that trigger the condition, such as allergens and certain medications. It is important for elderly patients to give their health care practitioner a complete list of medications, including over-the-counter drugs, that the patient takes both regularly and infrequently.

Asthma is treated primarily by two types of drugs: acute short-term medications and long-term medications. Acute medications give rapid, short-term relief, and are only used when asthma symptoms require immediate treatment. Acute medications are bronchodilators that may be inhaled or taken orally and take effect within minutes to dilate the airways and allow normal breathing. Bronchodilators may be used at the beginning of an asthma attack to provide relief. Bronchodilators may also be used before exercise to prevent exercise-induced asthma symptoms. Long-term control medications are taken daily over long periods of time to control chronic symptoms and prevent asthma attacks. The full effect of these medications requires several weeks of use.

Individuals with persistent asthma require long-term control medications. The most effective long-term control medication for asthma is an inhaled corticosteroid. Corticosteroids reduce the swelling of airways and help to prevent asthma attacks from occurring. Inhaled corticosteroids are preferred for treatment of all levels of persistent asthma. In some cases, steroid tablets or liquid medications are used temporarily to control asthma. Prolonged treatment of the elderly with oral corticosteroids can cause high blood pressure, diabetes, weight gain, and osteoporosis—a disease, occurring especially in women after menopause , in which the bones become very porous, break easily, and heal slowly. Physicians treating older patients for asthma need to take measures to prevent osteoporosis from developing.

Other types of asthma medications inhibit the inflammatory mediators released in the asthma response. Long-acting bronchiodialators, such as montelukast (Singulair), are also available for use as inhalers. A newer treatment, omalizumab (Xolair), is an antibody directed at the antibody IgE that is produced in allergic reactions. It is primarily used for allergic asthma that does not respond well to more standard therapies. Some long-term control medications may be used in combination with inhaled corticosteroids to treat moderate persistent and severe persistent asthma.

Long-term control medications are used to prevent an asthma attack and will not stop a currently occurring asthma attack. Many people with asthma require both a short-acting bronchodilator to use when symptoms worsen and a long-term daily asthma control medication to treat ongoing inflammation.

Emergency treatment

Emergency care may be necessary during a severe asthma attack. Emergency care takes place in a hospital setting and may include treatment with high levels of bronchodilators and corticosteroids, additional medications, and oxygen administration in an attempt to restore normal breathing. Delayed access to emergency treatment can lead to complete respiratory failure where the patient simply stops breathing and cannot be revived. In cases of allergic asthma, allergy shots may assist in reducing symptoms. Allergy shots, also known as allergen immunotherapy, are recommended for people who have allergic asthma but cannot avoid contact with the allergens that stimulate asthma. A series of shots with controlled and gradually increasing amounts of allergen are given over a number of months or years. The shots are vaccines containing various allergens, such as pollen or dust mites. Increased exposure to the allergen desensitizes the immune system to allergen triggers. Allergy shots can diminish the severity of asthma symptoms and lower the dosage of required asthma medications.

Nutrition/Dietetic concerns

There is some evidence of a link between obesity and asthma. It is important for people with asthma who are overweight or obese to reduce their weight to a normal level. Obese people without asthma who reduce their weight to a normal level may lessen their risk of developing asthma. Use of a class of medications called bisphosphonates, primarily used to strengthen bones, along with vitamin D and calcium supplements is recommended in older patients who require prolonged use of oral corticosteroids to treat their asthma.

Therapy

Use of an inhaler to take asthma medications is usually required, especially in people with severe asthma. It is important as a quality of life issue that elderly persons with asthma chose an inhaler that is both comfortable and easy for them to use.

Prognosis

When medication is used properly, the prognosis for most people with asthma is excellent. An improvement in environmental conditions can reduce the number and severity of asthma attacks and improve the prognosis for people with asthma. Elderly patients with severe asthma may develop anxiety and depression . Proper treatment and management can dramatically improved the quality of life for older people with asthma.

QUESTIONS TO ASK YOUR DOCTOR

• What treatments are available to treat my asthma?
• What are the side effects of asthma treatments?
• Are there alternative or complementary treatments available?
• What are inhalers and how are they used?
• How will asthma affect what I can do?
• What do I do if I have an asthma attack?

Prevention

There is no known way to prevent asthma but there are ways to decrease the chances of having an asthma attack.

• Learning about asthma and how to control it.
• Using medications under a doctor's guidance to prevent or stop attacks.
• Avoiding things that make asthma worse.
• Getting regular medical check-ups.
• Following an asthma self-management plan developed in conjunction with a physician.

Caregiver concerns

It is important for the caregiver to recognize symptoms of asthma and know how to react when the person they are caring for has an asthma attack. The caregiver should know where the patient's medication inhalers are kept and ensure the supply does not run out. At the first signs of an asthma attack, the caregiver should:

• Sit the person upright, remain calm, and provide the person with reassurance. Do not leave the person alone.
• Give the person four puffs from an inhaler, one puff at a time, preferably through a spacer device. Have the person take four breaths from the spacer after each puff of medication. If no spacer is available, use a inhaler on its own.
• Wait four minutes. If there is little or no improvement, the caregiver should repeat the inhaler treatment.
• If there is still little or no improvement, immediately call for an ambulance, paramedics, or fire-rescue. Continue inhaler treatment until medical help arrives.

KEY TERMS

Adrenergic-blocking agents —Medications used to treat some types of heart conditions and high blood pressure.

Allergen —A substance or organism foreign to the body; allergens stimulate the immune system to produce antibodies.

Allergy —A condition in which the immune system is hypersensitive to contact with allergens; an abnormal response by the immune system to contact with an allergen; condition in which contact with allergen produces symptoms such as inflammation of tissues and production of excess mucus in respiratory system.

Antibody —A protein produced by the mature B cells of the immune system that attach to invading microorganisms and target them for destruction by other immune system cells.

Bronchial tubes —The tubular passages that form part of a network of airways to and within the lungs.

Bronchodilators —Drugs that relax the main air passages in the bronchial tubes that carry air in and out of the lungs.

Chronic obstructive pulmonary disease (COPD) —A term referring to two lung diseases, chronic bronchitis and emphysema, that are characterized by obstruction to airflow that interferes with normal breathing.

Corticosteroid —A steroid hormone produced by the adrenal gland involved in metabolism and immune response.

Hypersensitive —A process or reaction that occurs at above normal levels; overreaction to a stimulus.

Inflammation —Swelling and reddening of tissue; usually caused by the immune system's response to the body's contact with an allergen.

Spirometer —An instrument for measuring the capacity of the lungs.

Resources

BOOKS

Berger, William E., M.D. Asthma for Dummies. Hoboken, NJ: Wiley Publishing, 2006.

Mahmoudi, Massoud. Allergy and Asthma: Practical Diagnosis and Management. New York: McGraw-Hill, 2007.

Mitchell, Dean. Dr. Dean Mitchell's Allergy and Asthma Solution: The Ultimate Program for Reversing Your Symptoms One Drop at a Time. New York: Marlowe & Company, 2006.

Pulmonary Disorders of the Elderly: Diagnosis, Prevention, and Treatment, edited by Thomas Petty and James S. Seebass. Philadelphia: American College of Physicians, 2007.

PERIODICALS

Bellia, Vincenzo, et al. “Asthma in the Elderly.” Chest October 2007: 1175–1182.

Fanta, Christopher H. “Plan for an Asthma Attack.” Adult Asthma (Harvard Special Health Report) Annual 2007: 41–43.

King, Monroe James. “Identifying and Treating Comorbidities Can Be Crucial—How Best to Diagnose and Control Asthma in the Elderly.” Journal of Respiratory Diseases June 1, 2006: 238.

Ramos, Rosemarie G., et al. “Community Urbanization and Hospitalization of Adults for Asthma.” Journal of Environmental Health April 2006: 26–32.

Wendling, Patrice. “Asthma Deaths Declining Overall, Most Common in Elderly.” Internal Medicine News June 1, 2006: 12.

“What Works Best to Control Asthma in Older Adults? It Isn't Only a Disease that Affects Children; Older People Can Suffer From Asthma, Too.” Focus on Healthy Aging December 2007: 1–2.

ORGANIZATIONS

American Academy of Allergy, Asthma, and Immunology, 555 E. Wells St., Suite 1100, Milwaukee, WI, 53202-3823, (414) 272-6071, (800) 822-2762, [email protected], http://www.aaaai.org.

American Lung Association, 61 Broadway, 6th Floor, New York, NY, 10006, (212) 315-8700, (800) 548-8252, http://www.lungusa.org.

Asthma and Allergy Foundation of America, 1233 20th St., NW, Suite 402, Washington, DC, 20036, (202) 466-7643, (800) 727-8462, [email protected], http://www.aafa.org.

British Lung Foundation, 73–75 Goswell Road, London, United Kingdom, EC1V 7ER, 08458 50 50 20, [email protected], http://www.lunguk.org.

National Heart, Lung, and Blood Institute, P.O. Box 30105, Bethesda, MD, 20824-0105, (301) 592-8573, (240) 629-3246, [email protected], http://www.nihlbi.nih.gov.

The Lung Association, 1750 Courtwood Crescent, Suite 300, Ottawa, ON, Canada, K2C 2B5, (613) 569-6411, (888) 566-5864, (613) 569-8860, [email protected], http://www.lung.ca.

Ken R. Wells