Asthma
is a complex clinical syndrome of chronic airway inflammation
characterized by recurrent, reversible, airway obstruction. Airway
inflammation also leads to airway hyperreactivity, which causes airways
to narrow in response to various stimuli.
Asthma is a common chronic condition, affecting approximately 8% to
10% of Americans, or an estimated 23 million Americans as of 2008.
Asthma remains a leading cause of missed work days. It is responsible
for 1.5 million emergency department visits annually and up to 500,000
hospitalizations. Over 3,300 Americans die annually from asthma.
Furthermore, as is the case with other allergic conditions, such as eczema (atopic dermatitis), hay fever (allergic rhinitis), and food allergies, the prevalence of asthma appears to be on the rise.
Symptom
Symptoms of asthma develop as a result of the narrowing and inflammation of the airways. Wheezing is a characteristic symptom of asthma, along with shortness of breath. Chest pain or tightness can accompany an asthma attack. Coughing can also be a symptom of asthma. The cough associated with asthma is often worse at night or in the early morning. Nighttime cough can lead to problems with sleep.
Symptoms vary among affected individuals. Some people have mild symptoms
that occur infrequently, while others have more frequent or more severe
symptoms. Severe asthma attacks can be life-threatening.
Asthma causes
Asthma results from complex interactions between an individual's
inherited genetic make-up and their interactions with the environment.
The factors that cause a genetically predisposed individual to become
asthmatic are poorly understood. The following are risk factors for
asthma:
- Family history of allergic conditions
- Personal history of hay fever (allergic rhinitis)
- Viral respiratory illness, such as respiratory syncytial virus (RSV), during childhood
- Exposure to cigarette smoke
- Obesity
- Lower socioeconomic status
Common Causes
- Asthma causes inflammation and narrowing of the airways in the lungs.
- Asthma is most common in people under 40 years of age
- Attack: When asthma symptoms become suddenly worse than usual, a person is said to be having an asthma attack. Severe asthma attacks can close the airways so much that vital organs do not get enough oxygen.
- Respiratory failure: Respiratory failure is a condition in which not enough oxygen passes from the lungs into the blood. Respiratory failure also can occur if your lungs can't properly remove carbon dioxide from your blood.
- Indoor and outdoor environmental factors such as dust mites, molds, cockroaches, pet dander, and secondhand smoke can trigger asthma attacks.
How is asthma diagnosed?
The diagnosis of asthma begins with a detailed history and physical
examination. A typical history is an individual with a family history of
allergic conditions or a personal history of allergic rhinitis who
experiences coughing, wheezing, and difficulty breathing, especially
with exercise or during the night. There may also be a propensity
towards bronchitis
or respiratory infections. In addition to a typical history,
improvement with a trial of appropriate medications is very suggestive
of asthma.
In addition to the history and exam, the following are diagnostic
procedures that can be used to help with the diagnosis of asthma:
- Lung function testing with spirometry: This test measures lung
function as the patient breathes into a tube. If lung function improves
significantly following the administration of a bronchodilator, such as albuterol,
this essentially confirms the diagnosis of asthma. It is important to
note, however, that normal lung function testing does not rule out the
possibility of asthma.
- Measurement of exhaled nitric oxide (FeNO): This can be performed by
a quick and relatively simple breathing maneuver, similar to
spirometry. Elevated levels of exhaled nitric oxide are suggestive of
"allergic" inflammation seen in conditions such as asthma.
- Skin testing for common aeroallergens: The presence of sensitivities
to environmental allergies increases the likelihood of asthma. Of note,
skin testing is generally more useful than blood work (in vitro
testing) for environmental allergies. Testing for food allergies is not
indicated in the diagnosis of asthma.
- Other potential but less commonly used tests include provocation
testing such as a methacholine challenge, which tests for airway
hyperresponsiveness. Hyperresponsiveness is the tendency of the
breathing tubes to constrict or narrow in response to irritants. A
negative methacholine challenge makes asthma much less likely.
Specialists sometimes also measure sputum eosinophils, another marker
for "allergic" inflammation seen in asthma. Chest imaging may show
hyperinflation, but is often normal in asthma. Tests to rule out other
conditions, such as cardiac testing, may also be indicated in certain
cases.
Treatment for asthma?
As per widely used guidelines, the treatment goals for asthma are to:
- adequately control symptoms,
- minimize the risk of future exacerbations,
- maintain normal lung function,
- maintain normal activity levels, and
- use the least amount of medication possible with the least amount of potential side effects.
Inhaled corticosteroids (ICS) are the most effective
anti-inflammatory agents available for the chronic treatment of asthma
and are first-line therapy per most asthma guidelines. It is well
recognized that ICS are very effective in decreasing the risk of asthma
exacerbations. Furthermore, the combination of a long-acting
bronchodilator (LABA) and an ICS has a significant additional beneficial
effect on improving asthma control.
The most commonly used asthma medications include:
- Short-acting bronchodilators (albuterol [Proventil, Ventolin,
ProAir, Maxair, Xopenex]) provide quick relief and can be used in
conjunction for exercise-induced symptoms.
- Inhaled steroids (budesonide, fluticasone, beclomethasone, mometasone, ciclesonide) are first-line anti-inflammatory therapy.
- Long-acting bronchodilators (salmeterol, formoterol) can be added to ICS as additive therapy. LABAs should never be used alone for the treatment of asthma.
- Leukotriene modifiers (montelukast, zarirlukast) can also serve as anti-inflammatory agents.
- Anticholinergic agents (ipratropium, tiotropium) can help decrease sputum production.
- Anti-IgE treatment (omalizumab) can be used in allergic asthma.
- Chromones (cromolyn, nedocromil) stabilize mast cells (allergic cells) but are rarely used in clinical practice.
- Theophylline
also helps with bronchodilation (opening the airways), but again is
rarely used in clinical practice due to an unfavorable side effect
profile.
- Systemic steroids (prednisone, prednisolone,
methylprednisone, dexamethasone) are potent anti-inflammatory agents
that are routinely used to treat asthma exacerbations but pose numerous
unwanted side effects if used repeatedly or chronically.
- Numerous other monoclonal antibodies are currently being studied but
none are currently commercially available for routine asthma therapy.
There is often concern about potential long-term side effects of
inhaled corticosteroids. Numerous studies have repeatedly shown that
even long-term use of inhaled corticosteroids has very few if any
sustained, clinically-significant side effects, including changes in
bone health, growth, or weight. However, the goal always remains to
treat all individuals with the least amount of medication that is
effective. Patients with asthma should be routinely reassessed for any
appropriate changes to their medical regimen.
Asthma medications can be administered via inhalers either with or
without an AeroChamber or nebulized solution. It is important to note
that if an individual has proper technique with an inhaler, the amount
of medication deposited in the lungs is no different than that when
using a nebulized solution. When prescribing asthma medications, it is
essential to provide the appropriate teaching on proper delivery
technique.
Smoking
cessation and/or minimizing exposure to secondhand smoke are critical
when treating asthma. Treating concurrent conditions such as allergic
rhinitis and gastroesophageal reflux disease (GERD) may also improve asthma control. Vaccinations such as the annual influenza vaccination are also indicated.
Although the vast majority of individuals with asthma are treated as
outpatients, treatment of severe exacerbations can require management in
the emergency department or inpatient hospitalization. These
individuals typically require use of supplemental oxygen, early
administration of systemic steroids, and frequent or even continuous
administration of bronchodilators via a nebulized solution. Individuals
at high risk for poor asthma outcomes are referred to a specialist
(pulmonologist or allergist). The following factors should prompt
consideration or referral:
- History of ICU admission or multiple hospitalizations for asthma
- History of multiple visits to the emergency department for asthma
- History of frequent use of systemic steroids for asthma
- Ongoing symptoms despite the use of appropriate medications
- Significant allergies contributing to poorly-controlled asthma
What is an asthma action plan?
Patient education is a critical component in the successful
management of asthma. An asthma action plan provides an individual with
specific directions for daily management of their asthma and for
adjusting medications in response to increasing symptoms or decreasing
lung function, as usually measured by a peak flow meter.
What is the prognosis for asthma?
The prognosis for asthma is generally favorable. Children experience
complete remission more often than adults. Although adults with asthma
experience a greater rate of loss in their lung function as compared to
age-controlled counterparts, this decline is usually not as severe as
seen in other conditions, such as chronic obstructive pulmonary disease
(COPD) or emphysema. Asthma in the absence of other comorbidities does
not appear to shorten life expectancy. Risk factors for poor prognosis
from asthma include:
- History of hospitalizations, especially ICU admissions or intubation
- Frequent reliance on systemic steroids
- Significant medical comorbidities
Can asthma be prevented?
With the increasing prevalence of asthma, numerous studies have
looked for risk factors and ways to potentially prevent asthma. It has
been shown that individuals living on farms are protected against
wheezing, asthma, and even environmental allergies. The role of air
pollution has been questioned in both the increased incidence of asthma
and in regards to asthma exacerbations.
Climate change is also being studied as a factor in the increased incidence of asthma. Maternal smoking during pregnancy
is a risk factor for asthma and poor outcomes. Tobacco smoke is also a
significant risk factor for the development and progression of asthma.
The development of asthma is ultimately a complex process influenced by
many environmental and genetic factors, and currently there is no proven
way to decrease an individual's risk of developing asthma.
Source:Medicinenet
ASTHMA HERBS
- Angelica: possess anti-inflammatory properties and increases immune system function; which is why the root is often used in treating allergies as well.
- Anise: often an ingredient in cough syrups and lozenges as an expectorant, which means it helps in the coughing up of mucus in conditions like asthma, bronchitis, the common cold and whooping cough.
- Coltsfoot: since the principal active ingredient in the plant is a throat-soothing mucilage, it has been used medicinally as a cough suppressant and remedy for asthma and bronchial congestion.
- Elecampane: long valued as a tonic herb for the respiratory system. It is often used as a specific remedy for chronic bronchitis and bronchial asthma. Elecampane soothes the bronchial tube linings and acts as an expectorant.
- Horehound: anti-inflammatory and is often used to treat respiratory aliments such as asthma, bronchitis and whooping cough.
- Licorice: has been used traditionally to restore breathing and calm the breathing passageways.
- Lobelia: is a bronchodilator and antispasmodic which explains its popularity as a medicinal herb for asthma, spasmodic croup, pneumonia and whooping cough. It is thought to stimulate the respiratory center of the brain resulting in deeper and stronger breathing.
- Marshmallow: a powerful anti-inflammatory and anti-irritant. The soothing and healing properties that are found in the mucilage in marshmallow make it a valuable herb for many lung ailments such as asthma.
- Motherwort: decreases the severity of lung spasms but also reduce anxiety, thus lessening the chance of an attack.
- Mullein: contains antiseptic agents and is mostly used today for chest ailments including asthma, bronchitis, pneumonia, pleurisy and whooping cough.
- Passionflower: decreases the severity of lung spasms but also reduce anxiety, thus lessening the chance of an attack.
- Skullcap: due to its anti-spasmodic and sedative effects, it is also great for treating throat infections and incessant coughing.
- Slippery Elm: has anti-inflammation and anti-irritant properties and is often recommended for lung conditions such as asthma, bronchitis, sore throats, coughs, pleurisy, or lung bleeding.
- Turmeric: powerful anti-inflammatory and it is believed to reduce inflammation. Shows a similar efficacy to cortisone.
- Wild Cherry: is an expectorant, antispasmodic, and antitussive. These properties indicate its usefulness as a preparation for bronchitis or whooping cough and can be helpful in coughs that accompany pneumonia. It is also helpful in coughs with influenza, where there is associated shortness of breath and or wheezing.
