Asthma

Asthma is characterized by inflammation of the air passages resulting in the temporary narrowing of the airways that transport air from the nose and mouth to the lungs. Asthma symptoms can be caused by allergens or irritants that are inhaled into the lungs, resulting in inflamed, clogged and constricted airways. Symptoms include difficulty breathing, wheezing, coughing tightness in the chest. In severe cases, asthma can be deadly.

Asthma is a chronic inflammatory disorder of the airways in which many cells and cellular elements play a role, in particular, mast cells, eosinophils, T lymphocytes, macrophages, neutrophils, and epithelial cells. In susceptible individuals, this inflammation causes recurrent episodes of wheezing, breathlessness, chest tightness, and coughing, particularly at night or in the early morning. These episodes are usually associated with widespread but variable airflow obstruction that is often reversible either spontaneously or with treatment. The inflammation also causes an associated increase in the existing bronchial hyper-responsiveness to a variety of stimuli.

The inside walls of an asthmatic’s airways are swollen or inflamed. This swelling or inflammation makes the airways extremely sensitive to irritations and increases your susceptibility to an allergic reaction.

As inflammation causes the airways to become narrower, less air can pass through them, both to and from the lungs. Symptoms of the narrowing include wheezing (a hissing sound while breathing), chest tightness, breathing problems, and coughing. Asthmatics usually experience these symptoms most frequently during the night and the early morning. Asthma is an incurable illness. However, with good treatment and management there is no reason why a person with asthma cannot live a normal and active life.

Asthma is among the most common chronic childhood illnesses, accounting for 10.5 million missed school days a year. It also accounts for 14.2 million lost workdays for adults. Every year, about 14 million Americans see a doctor for asthma. About 1.4 million patients visit a hospital outpatient department for asthma; almost 1.75 million go to a hospital emergency room. The number of people in the U.S. diagnosed with asthma is increasing.

How is an Asthma Attack?

An asthma episode, or an asthma attack, is when symptoms are worse than usual. They can come on suddenly and can be mild, moderate or severe.

• The muscles around the airways tighten up, narrowing the airway.
• Less air is able to flow through the airway.
• Inflammation of the airways increases, further narrowing the airway.
• More mucus is produced in the airways, undermining the flow of air even more.

Types of Athma

• Child-Onset Asthma – Asthma that begins during childhood is called child-onset asthma. This type of asthma happens because a child becomes sensitized to common allergens in the environment – most likely due to genetic reasons. The child is atopic – a genetically determined state of hypersensitivity to environmental allergens.
• Adult-Onset Asthma – This term is used when a person develops asthma after reaching 20 years of age. Adult-onset asthma affects women more than men, and it is also much less common than child-onset asthma. It can also be triggered by some allergic material or an allergy. It is estimated that up to perhaps 50% of adult-onset asthmas are linked to allergies. However, a substantial proportion of adult-onset asthma does not seem to be triggered by exposure to allergen(s); this is called non-allergic adult-onset asthma.
• Exercise-Induced Asthma – If a person coughs, wheezes or feels out of breath during or after exercise, he or she could be suffering from exercise-induced asthma. Obviously, the level of fitness is also a factor – a person who is unfit and runs fast for ten minutes is going to be out of breath. However, if the coughing, wheezing or panting does not make sense, this could be an indication of exercise-induced asthma.
• Cough-Induced Asthma – Cough-induced asthma is one of the most difficult asthmas to diagnose. The doctor has to eliminate other possibilities, such as chronic bronchitis, post nasal drip due to hay fever, or sinus disease.
• Occupational Asthma – This type of asthma is triggered by something in the patient’s place of work. Factors such as chemicals, vapors, gases, smoke, dust, fumes, or other particles can trigger asthma. It can also be caused by a virus (flu), molds, animal products, pollen, humidity and temperature.
• Nocturnal Asthma – Nocturnal asthma occurs between midnight and 8 AM. It is triggered by allergens in the home such as dust and pet dander or is caused by sinus conditions. Nocturnal or nighttime asthma may occur without any daytime symptoms recognized by the patient.
• Steroid-Resistant Asthma (Severe Asthma) – While the majority of patients respond to regular inhaled glucocorticoid (steroid) therapy, some are steroid resistant. Airway inflammation and immune activation play an important role in chronic asthma. Current guidelines of asthma therapy have therefore focused on the use of anti-inflammatory therapy, particularly inhaled glucocorticoids (GCs).

Cause

Allergies – Almost all asthma sufferers have allergies. In fact, over 25% of people who have hay fever (allergic rhinitis) also develop asthma. Allergic reactions triggered by antibodies in the blood often lead to the airway inflammation that is associated with asthma. Common sources of indoor allergens include animal proteins (mostly cat and dog allergens), dust mites, cockroaches, and fungi. It is possible that the push towards energy-efficient homes has increased exposure to these causes of asthma.

Environmental Factors – Pollution, sulfur dioxide, nitrogen oxide, ozone, cold temperatures, and high humidity have all been shown to trigger asthma in some individuals. During periods of heavy air pollution, there tend to be increases in asthma symptoms and hospital admissions. Smoggy conditions release the destructive ingredient known as ozone, causing coughing, shortness of breath, and even chest pain. These same conditions emit sulfur dioxide, which also results in asthma attacks by constricting airways.

Pregnancy – Babies born by Caesarean sections have a 20% increase in asthma prevalence compared to babies born by vaginal birth. It is possible that immune system-modifying infections from bacterial exposure during Cesarean sections are responsible for this difference.

Obesity – Overweight adults – those with a body mass index (BMI) between 25 and 30 – are 38% more likely to have asthma compared to adults who are not overweight. Obese adults – those with a BMI of 30 or greater – have twice the risk of asthma. According to some researchers, the risk may be greater for nonallergic asthma than allergic asthma.

Tobacco smoke has been linked to a higher risk of asthma as well as a higher risk of death due to asthma, wheezing, and respiratory infections. In addition, children of mothers who smoke – and other people exposed to second-hand smoke – have a higher risk of asthma prevalence. Adolescent smoking has also been associated with increases in asthma risk.

Stress – People who undergo stress have higher asthma rates. Part of this may be explained by increases in asthma-related behaviors such as smoking that are encouraged by stress. However, recent research has suggested that the immune system is modified by stress as well.

Genetic Factors – Genes linked to asthma also play roles in managing the immune system and inflammation. There have not, however, been consistent results from genetic studies across populations – so further investigations are required to figure out the complex interactions that cause asthma.

Inflammatory Triggers – Inflammatory (allergic) triggers can cause inflammation of the lungs’ airways or tightening of the airways’ muscles. Inflammatory triggers include –

• Dust mites
• Animals
• Cockroaches
• Moulds
• Pollens
• Viral infections
• Certain air pollutants

Symptom Triggers – Symptom (non-allergic) triggers generally do not cause inflammation, but they can provoke “twitchy” airways, especially if they’re already inflamed. Symptom triggers include-

• Smoke
• Exercise
• Cold air
• Chemical fumes and other strong-smelling substances like perfumes
• Certain food additives like sulfites
• Certain air pollutants
• Intense emotions

Symptoms

Asthma symptoms can differ for each person, but here are some of the most common:

• Wheezing – People may notice a whistling sound when you breathe. Sometimes this happens only when you exercise or have a cold.
• Frequent cough – This may be more common at night. People may or may not cough up mucus.
• Shortness of breath – This is the feeling that you can’t get enough air into the lungs. It may occur only once in a while, or often.
• Chest tightness – The chest may feel tight, especially during cold weather or exercise. This can also be the first sign of a flare-up.

Treatment

Conventional Treatment

Medicine – Long-term asthma control medications, generally taken daily, are the cornerstone of asthma treatment. These medications keep asthma under control on a day-to-day basis and make it less likely you’ll have an asthma attack. Types of long-term control medications include –

• Inhaled corticosteroids – These anti-inflammatory drugs include fluticasone (Flonase, Flovent HFA), budesonide (Pulmicort Flexhaler, Rhinocort), flunisolide (Aerospan HFA), ciclesonide (Alvesco, Omnaris, Zetonna), beclomethasone (Qnasl, Qvar), mometasone (Asmanex) and fluticasone furoate (Arnuity Ellipta).
• Leukotriene modifiers. These oral medications — including montelukast (Singulair), zafirlukast (Accolate) and zileuton (Zyflo) — help relieve asthma symptoms for up to 24 hours.
• Long-acting beta agonists – These inhaled medications, which include salmeterol (Serevent) and formoterol (Foradil, Perforomist), open the airways.
• Combination inhalers – These medications — such as fluticasone-salmeterol (Advair Diskus), budesonide-formoterol (Symbicort) and formoterol-mometasone (Dulera) — contain a long-acting beta agonist along with a corticosteroid.
• Theophylline – Theophylline (Theo-24, Elixophyllin, others) is a daily pill that helps keep the airways open (bronchodilator) by relaxing the muscles around the airways.
• Short-acting beta agonists – These inhaled, quick-relief bronchodilators act within minutes to rapidly ease symptoms during an asthma attack. They include albuterol (ProAir HFA, Ventolin HFA, others) and levalbuterol (Xopenex).
• Ipratropium (Atrovent) – Like other bronchodilators, ipratropium acts quickly to immediately relax your airways, making it easier to breathe.
• Oral and intravenous corticosteroids – These medications — which include prednisone and methylprednisolone — relieve airway inflammation caused by severe asthma.

Alternative Treatment

Vitamins – Antioxidant vitamins are commonly suggested complementary therapies for asthma. Adults whose diets are naturally high in antioxidants such as vitamin C– and vitamin E–rich foods have the fewest pulmonary problems.

Magnesium – Dietary magnesium intake is strongly correlated with asthma symptoms; the more magnesium, the fewer the symptoms. Intravenous magnesium has proven helpful in treating pediatric status asthmatics.

Selenium – Plasma and erythrocyte levels of selenium and the activity of the selenium-dependent enzyme glutathione reductase are lower in asthmatic adults than in non-asthmatics.

Salt restriction – While bronchial sensitivity to methacholine is increased by high salt intakes, a pediatric case control study found no association between levels of salt intake and asthma or exerciseinduced bronchospasm.

Fatty acids – Omega-3 fatty acids (found in fish oils, canola oil, and flax seed oil) have been touted as important anti-inflammatory food supplements. Omega-3 fatty acids limit leukotriene synthesis by blocking arachidonic acid metabolism.

Zinc – There is little evidence of zinc deficiency causing asthma symptoms, but asthma patients have been shown to have lower plasma zinc than healthy controls.

Ginkgo extract has been shown to reduce inflammation.

Lobelia (Indian tobacco) was used by Native Americans to treat respiratory disorders, including asthma.

Other natural herbs that have been used to treat asthma include mullein, boswellia (Indian frankincense), dried ivy, and butterbur.

Coffee and tea can both be useful in treating asthma symptoms. Caffeine is a natural (mild) bronchodilator. Tea contains minute amounts of theophylline, one of the major prescription drugs for asthma.

Complementary Treatment

Acupuncture – A technique that involves inserting needles into key points of the body. Evidence suggests that acupuncture may signal the brain to release endorphins. These are hormones made by the body.

Biofeedback – A technique that helps people control involuntary physical responses. Results are mixed, with children and teenagers showing the greatest benefit.

Chiropractic spinal manipulation – A technique that emphasizes manipulation of the spine in order to help the body heal itself. There is no evidence that this treatment impairs the underlying disease or pulmonary function.

Hypnosis – An artificially induced dream state that leaves the person open to suggestion, hypnosis is a legitimate technique to help people manage various conditions. Hypnosis might give people with asthma or allergies more self-discipline to follow good health practices.

Laser treatment – A technique that uses high intensity light to shrink swollen tissue or unblock sinuses.

Massage, relaxation techniques, art/music therapy, yoga – Stress and anxiety may cause your airways to constrict more if you have asthma or allergies. Various techniques can help you relax, reduce anxiety or control your breathing.

 

Reference –

http://www.lung.org/lung-health-and-diseases/lung-disease-lookup/asthma/diagnosing-treating-asthma/

http://www.nhs.uk/Conditions/Asthma/Pages/Symptoms.aspx

http://www.medicalnewstoday.com/info/asthma/treatment-for-asthma.php

http://www.nhlbi.nih.gov/health/health-topics/topics/asthma/treatment

http://www.nationalasthma.org.au/understanding-asthma/what-is-asthma-#2

http://www.asthma.ca/adults/about/symptomTriggers.php

http://acaai.org/asthma/about

https://www.blf.org.uk/Page/Causes-of-asthma

http://www.healthline.com/health/natural-asthma-treatment-and-alternative-therapies#Overview1

http://www.asthmaaustralia.org.au/Complementary_Therapies.aspx

https://dphhs.mt.gov/Portals/85/publichealth/documents/Asthma/CAMUseandAsthma.pdf