Asthma is a common and recurrent breathing disorder that often requires long-term treatment. The bronchial tubes spasm, causing tightness in the chest and shortness of breath. Wheezing and coughing are common, and breathing sounds noisy. In severe asthma, air entry into the chest is so poor that the chest makes no sounds at all. Episodes can last for seconds, minutes or much longer. Anxiety, fear, and panic may accompany asthma episodes as a reaction to oxygen deprivation or “air hunger.”
The asthmatic pathway is a complex system with many components. Obstruction and chronic inflammation occurring intermittently in the hypersensitive airway insults the pathway causing recurrent, severe, and irreversible damage. The airway and distant parts of the body are compromised due to oxygen deprivation. Quality of life is often diminished with patients losing days at school and work, and missing family life. The worst cases of asthma can involve a progression to irreversible obstructive lung disease. Asthma is not cured, but managed over the lifetime.
Children with asthma often have mild or intermittent symptoms that require minimum treatment. Some children have persistent problems that could become severe. Very small children and those that may need high doses of medications should be rigorously evaluated for other medical diagnoses or causes. While most cases of asthma in children are mild and respond to treatment, the airway can be irreversibly damaged and children do suffer from lingering sickness and early death.
Adults who develop asthma often have workplace exposure to toxins. Airway irritants can be from immunological or non-immunological agents, meaning a toxin could be causing an allergy or not. If an allergy is detected, the worker is advised to cease that activity. If no allergy is detected, the worker is advised to seek accommodations or preventative measures to lessen the impact of the culprit toxin or irritant. Typically, those occupations likely to develop asthma are farmers, bakers, carpenters, and factory workers especially those involved in manufacturing plastics, foams, and glues.
Types of Asthma
- Infrequent intermittent – mild episodes occur less than every 6-8 weeks, no daytime or nighttime symptoms.
- Frequent intermittent – mild episodes, maximum 2 episodes per week, no daytime or nighttime symptoms.
Mild Persistent Asthma
- Episodes occur not every day, but at least once a week, up to two times a week, but not more than once a day. Symptoms may affect activities and sleep may be disrupted a few times a month.
Moderate Persistent Asthma
- Episodes occur daily and disrupt sleep at least once a week. Activities are affected by daily attacks.
Severe Persistent Asthma
- Frequent attacks daily and nightly so that physical activity, social activities and sleep is disrupted.
Asthma is found in 300 million people across the globe and is expected to rise at least another 100 million in the next ten years. Asthma patients often wind up in emergency rooms. The U.S. counted 2 million emergency room visits in one year for asthma-related trauma, with 100 million days of work lost. One study found that children with poorly controlled asthma miss ten times the school days as children with controlled asthma.
While studies show that insurance status, the status of having insurance, improves the chances that someone will seek treatment and therefore have their asthma controlled, insurance status has no effect on hospitalization rates. Whether someone has insurance or not, they will still seek emergency care. Acute care utilization, because of the seriousness of the condition, may have to be accepted by the patient, family, and health care system.
Causes of Asthma
Chronic inflammation underlies the complex disease process in Asthma, partly due to genetic make-up, which may trigger environmental hyper-responsiveness. The trigger provokes inflammatory mediators which call other inflammatory cells to migrate to the large and the small airways. The entire airway becomes inflamed due to the T-helper type 2 (Th2) lymphocytic response. Smooth muscle mass increases and contracts more. Deposits of dead cells, proteins, mucus, and collagen remodel the airway and lungs.
The asthmatic pathway includes:
- epithelial cells
- mast cells
- T lymphocytes
Genes involved include:
- chromosome 12q
- dipeptidyl peptidase 10
- PHD finger protein 11
- polymorphisms in tumor necrosis factor (TNF)
- prostanoid DP1 receptor
Environmental triggers include:
- allergen exposure like trees, grass or mold
- bacterial infections
- food additives
- occupational exposures like chemicals
- viral infections
- Strong emotions – deprivation of oxygen or feeling like you are slowly suffocating, is a life-threatening event which people often respond to with emotional arousal in a cascade of reactions like panic, anxiety, fear and hysteria. A global sympathetic nervous system or adrenal system activation causes these feelings. In addition, some asthmatic attacks have been initiated by strong emotions.
- Death – those with uncontrolled asthma, those exposed to a single event of high allergic potential, those with previous history of near death, those using long-acting beta agonists (LABA) without a corticosteroid, and those with a psychiatric disorder have a high risk.
- Obstructive lung disease – a result of long-term remodeling of the airway, severe exacerbations of asthma, and a more rapid deficit in lung function.
- Dental Health – teeth cavities and gingivitis are more prevalent in asthmatic children, adolescents, and adults. Asthmatics often become dry in the mouth and may use more sugary drinks and/or medications may reduce the amount of saliva in the mouth.
- Infection and Flu – asthmatics who become ill with infections or the flu always become worse, need more supplemental oxygen and greater respiratory treatment distress. Mucus and inflammatory cells camp out in the airways and block air movement.
- Lung function – children with severe asthma are at risk for permanent lung damage as they grow older.
- Sense of Smell – loss of the sense of smell is common for all asthmatics regardless of the severity of the disease. Smell loss can be used to detect asthma as well.
- Sleep – all asthma patients have a poorer quality of sleep, even when not reporting nighttime disturbances. Poor sleep then makes asthma states worse with poorer asthma control and quality of life.
- Allergens – dust mites, pets, tobacco smoke, cockroaches, fungal spores, fumes from chemicals, and pollen from trees, weeds, and grass.
- Atopic diseases – eczema and allergic rhinitis.
- Respiratory tract infections.
- Nasal polyps – often found in late-onset asthma.
- Family history – children with a parent who has asthma often develop asthma.
- Aspirin intolerance.
- Obesity – overweight and obese people have greater incidence of asthma. Overweight children are at twice the risk as normal children.
- Belly Fat – central obesity is associated with 2 times the risk of asthma.
- Hormone Replacement Therapy (HRT) – drugs that women take to ease menopause are associated with a greater increase in hospitalizations for asthma.
- Smoking – people who smoke or have smoked in their lifetime are more likely to develop asthma.
- Chronic rhinosinusitis – people with chronic nasal congestion and a runny nose are likely to be asthmatic.
- Maternal status – both physical and mental conditions like anemia and depression in the mother are associated with asthmatic stress for the child.
- Early Antibiotic Use – babies who are given antibiotics may be 50% more likely to develop asthma by the age of six.
- A cold or upper respiratory infection.
- A tight feeling in the chest.
- Allergies – sneezing, runny nose, cough, congestion, sore throat, and headache.
- Blue lips or fingernails.
- Coughing, especially at night, with exercise, or when laughing.
- Difficulty talking.
- Feeling tired, grouchy, or moody.
- Feelings of anxiety or panic.
- Inability to speak
- Pale, sweaty face.
- Strong emotions trigger symptoms – shouting, crying, or laughing.
- Tight neck and chest muscles.
- Tired or weak when exercising or after exercising.
- Trouble breathing – gasping for air or rapid breathing.
- Trouble sleeping.
- Wheezing – a squeaky or whistling sound.
Diagnosis of Asthma
Identifying the patient’s pattern of episodes, evaluating the risk factors, symptoms, and confirming with tests is part of the diagnostic process. Diagnosis of a child patient and an adult patient may differ. Adult patients are more likely to have an environmental trigger, whereas children are more likely to have a medical condition that causes asthma. Finding the cause in adult patients is more like solving a mystery, unlike for children, which is more about excluding other pathologies. The physician will check your vital signs and use a stethoscope to listen to your airway.
You may complete an Asthma Control Questionnaire and an Asthma Control Diary. Some of the questions that the physician may ask in order to solve the mystery or exclude other pathologies include:
- What factors make the asthma worse?
- When does the asthma happen: during exercise, during the night or day, during different seasons?
- What does it feel like when episodes occur?
- Do you have pets in the house?
- What kind of chemicals do you use at home or work?
- Do people smoke in your home or work?
- Do you have pain anywhere, like in your nose?
Laboratory tests will depend on the symptoms, degree of severity, complicating factors like other illnesses, physician preference, insurance status, test availability, and by the locality or country. Airway tests are used to establish baseline capabilities and reversibility if treatment is given.
Common tests may include:
CXR – chest x-ray may show signs of infection, and useful to rule out other causes.
FBC – full blood count, may show raised esinophils and/or neutrophilia in asthma.
Challenge tests – agents are used to constrict the airway directly or indirectly in order to establish how the airway is modeled and to what degree is it inflamed and hyper-responsive. Common direct agents are histamine or methacholine and indirect agents like exercise, mannitol, and inhaled saline solution.
Pulmonary Function Testing (PFT) also known as Spirometry:
- Forced Expiratory Volume at 1 second (FEV1) – normally shows 230 mL or 14% improvement after treatment with a bronchodilator. If the patient shows a 20% improvement, the test is diagnostic for asthma.
- Forced Vital Capacity (FVC) – the difference between the inhaled breath and the exhaled breathe.
- FEV1/FVC ratio – the primary diagnostic tool is the ratio of forced expiratory volume at 1 second (FEV1) to the forced vital capacity (FVC). This test shows the airway obstruction. When the patient is then given a short-acting bronchodilator and the asthma reverses by 12% and 200 ml, the diagnosis of asthma is confirmed. This test is repeated yearly.
- Peak Expiratory Flow Rate (PEFR) – evaluates the variability according the day or night schedule. The rate is expressed as the highest daily number minus the lowest number divided by the highest daily PEFR. If the airway flow rate improves by at least 20% after asthma treatment, the diagnosis of asthma is confirmed. This test can be performed in the doctor’s office and monitoring can be continued at home. However, this test does not perform as well for lung function as does the FEV1 and FEV1/FVC ratio.
Allergy testing – useful for people who may be triggered by environmental factors. Skin prick testing and serum IgE levels are reliable indicators for allergens.
Exhaled Nitric Oxide Levels– not a standard test, but it is highly specific and sensitive, and can be used to monitor progress over time.
Peak Expiratory Flow Rate (PEFR) – uses the patient’s best peak flow to monitor progress. Flow monitoring is useful for moderate to severe patients in order to track changes in airway efficiency, evaluate drug efficacy, and guide decision making in the asthma disease course.
- Mild intermittent: Forced expiratory flow at 1 second (FEV1) or PEFR ≥80% of predicted, PEFR variability <20%.
- Mild persistent: FEV1 ≥80% of predicted, PEFR variability between 20% and 30%.
- Moderate persistent: FEV1 greater than 60% to <80% of predicted, PEFR variability >30%.
- Severe persistent: FEV1 ≤60% of predicted, PEFR variability >60%.
Treatment of Asthma
The airway obstruction causing asthma may resolve on its own or require intervention. Individual treatment plans will vary, according to the severity of the asthma, the physician’s directives, and the patient’s ability to comply with recommendations. The ongoing task for asthma patients is to monitor their peak expiratory flow daily. In a similar way to diabetics who monitor their blood sugar every day, asthmatics need to have the tools to be on guard against a severe attack. Monitoring the airway flow allows specific and targeted actions, improves the quality of life and avoids hospitalization.
Asthma control is a management system for the environment, medications, exercise, diet, sleep and other medical conditions. Physicians seek to get the maximum benefit from drug treatment with the lowest possible dosage. Successful asthma control is a state where the patient has no symptoms and is able to lead a normal and productive life. After control is reached, medications can be adjusted downwards to further limit drug usage while still maintaining control. The following are treatment options for mild to severe asthma. Only a physician can counsel the patient, prescribe medication and monitor the patient’s progress.
Inhaled Short-Acting Beta-2 Agonist (SABA) – all asthma patients may be prescribed this metered dose inhaler. If patients are using the device more than 2 days a week, the asthma is not in control. SABA’s are deployed on an ‘as required’ basis or prior to exercise.
- Salbutamol: inhaled at 100-200 micrograms/dose (1-2 puffs)
- Levosalbutamol: inhaled at 45-90 micrograms/dose (1-2 puffs)
Injectable Adrenaline – all asthma patients should carry a SABA inhaler and an injectable adrenaline preparation in order to be prepared for an extreme asthma event.
Inhaled Corticosteroid (ICS) – added to the treatment regimen in a metered dose inhaler if the SABA is not enough.
- Fluticasone: inhaled at 50-300 micrograms/dose
- Budesonide: inhaled at 90-600 micrograms/dose
- Triamcinolone: inhaled at 100-1000micrograms/dose
- Flunisolide: inhaled at 80-320 micrograms/dose
- Beclometasone: inhaled at 50-800 micrograms/dose
- Mometasone: inhaled at 200 micrograms/dose
- Ciclesonide: inhaled 80 or 160 micrograms/dose
Allergen Immunotherapy – for patients with confirmed allergies, Omalizumab is an effective immunomodulator.
Leukotriene-Receptor Antagonist (LTRA) – offered after trial of SABA and corticosteroids. These preparations are very safe in the long-term and have some effectiveness in downgrading symptoms. They are not used for sudden attacks of asthma. A trial period of use is preferred to establish dosage and guard against toxicity.
- Sodium Cromoglicate: inhaled in 20 mg/dose four times a day.
- Theophylline: a sustained release bronchodilator. Orally delivered in 10-300 mg dosage.
- Montelukast:10 mg orally once a day usually in the morning.
- Zafirlukast: 20 mg orally two times a day.
- Nedocromil: inhaled in 2-4 mg/dose four times a day.
Long-Acting Beta Agonist (LABA)
- Salmeterol: inhaled at 50 micrograms/dose two times a day.
- Formoterol: inhaled at 12 micrograms/dose every 12 hours.
Supplemental Medications and Aids
- Oxygen – may be used in a hospital setting, or for severe attacks.
- Inhaled anticholinergic – inhibits nerves and reduces airway spasms.
- Magnesium – inhibits airway spasms.
- Heliox – a breathing gas used in the hospital.
- Mechanical ventilation – a machine used to force air into the cardiopulmonary system.
- Antibiotic therapy – to treat respiratory infections common to asthmatics.
- Systemic corticosteroid – an injection of medication that reaches all parts of the body, not just the airway as SABAs do. Offered in severe attacks or in persistent and severe asthma.
The act of exercising, with its increased cardiopulmonary demands, may induce asthma symptoms in more than half of patients. Since exercise is such an important health behavior, patients are offered additional options to cope with symptoms. Inhaled corticosteroids (ICS), sodium cromoglycate, nedocromil sodium, leukotriene receptor antagonists or a bronchodilator can be used before, during and after exercise.
All people need to examine their homes and workplaces for potential toxins and allergens. People with asthma especially, must take measures to control their environment and limit asthma symptoms. Dust mites, animals, and cigarette smoke contribute to indoor asthma risks. Outside, seasonal variations, pollen, and grass may be culprits. In the workplace, chemicals are often found and need to be eliminated or controlled.
Every person is different and an investigation into asthma triggers is undertaken in the beginning, and should continue through the lifetime. Specific drugs like aspirin and NSAIDS like ibuprofen, may need to be avoided. Smoking cigarettes and recreational drugs are better avoided for asthmatics. Food choice is also important, especially eliminating culprit compounds like sulfites.
Self-monitoring using a PEFR meter, records the peak expiratory flow rate (PEFR). Patients check their rate daily and compare it to standards set by their physician. If the flow rate is within normal range, asthma is controlled. If the data shows deficits, patients can adjust their medications according to prior instructions from the doctor. Self-monitoring with the device is critical as patients often cannot sense worsening of asthma. Testing frequency depends on the severity of the symptoms. Some patients may need once daily testing while others may need frequent testing throughout the day.
Medication compliance is an issue in all aspects of medical care. Patients often misunderstand instructions and doses, forget to take their medications or are openly defiant in taking medication. Studies show that about half of asthma patients do not take their medications as directed. Continuing follow-up with their physician is very important for compliance, as well as for adjusting dosage and planning for eventualities.
Children with asthma may be expected to have permanent changes and remodeling of the airway and deficits in lung function. Even young adults who develop asthma have airway remodeling. The permanent changes may be mild, moderate or severe depending on the severity of the asthma. However, people with controlled asthma, those who are compliant with taking medications, have a similar life expectancy as the rest of the population.
Prevention of Asthma
Complementary and alternative medicine is commonly used to treat asthma and prevent it. Alternative strategies are especially prevalent in regions where formal medical care is unavailable. Use of these treatments is considered helpful and not harmful. However, researchers are concerned that alternative therapies are over-used in the case of asthma.
About 13 – 60% of parents who have children with asthma, use acupuncture, homeopathy, chiropractic medicine or herbal therapy to treat or prevent asthma. Unfortunately, using alternative medicine is not helpful for asthma as children who use homeopathy have two times poorer outcomes than those who take traditional pharmacological medicine.
The following strategies are proven effective in preventing asthma:
- Allergen and Toxins elimination – a rigorous screening of the home and workplace is recommended.
- Smoking – all people can do without the harmful toxins found in cigarettes.
- Body Weight – normal body weight is important for medical, mental, and disease prevention reasons.
- Supplementation – some over the counter supplements and foods like those with fish oil can be helpful in preventing chronic inflammation. Vitamin C has been shown to have small protective qualities against asthma.
- Vaccinations – can be helpful in preventing infections and disease states which may lead to asthma.
- Pregnancy – proper care, nutrition and social environment is critical to foster an environment in the womb that sets the child up for success. Mothers who were anemic while pregnant have children with asthma and other problems. Women exposed to stress and neglect may end up coding the genes of their child with medical and emotional deficiencies.
- Mepolizumab – the Th2 immune response activates other inflammatory cells. Mepolizumab may be a possible new drug that reduces the inflammatory response.
- Infliximab – an anti-tumor medication given in conjunction with corticosteroids may inhibit asthma symptoms.
- Etanercept – TNF-alpha is elevated in asthma so this drug acts to block the TNF receptor.
A new procedure to mechanically control asthma is in use in a bronchial thermoplastic, bronchoscopic procedure. Thermal or radiofrequency energy is released through a tube into the airway wall, which acts to reduce contractions in the smooth muscles. This procedure is recommended for severe cases of asthma, when drugs do not work or if the patient may otherwise be a good candidate. The procedure is approved but may only be available in limited areas.
Researchers have developed and validated a survey tool that measures parent and child anxiety. Measuring anxiety is important as the emotional state of anxiety is associated with overreactions to symptoms and over-use of medications. The questionnaires are called the Youth Asthma-related Anxiety Scale (YAAS) and the Parent Asthma-related Anxiety Scale (PAAS).
A Text Message Program
The new adherence and compliance program may improve asthma outcomes. People with asthma on prescribed medications participated in a novel program designed to improve their perceptions about asthma and their compliance in taking medications. Those who got individually tailored messages based on their illness and medications got text messages over an eighteen week period. The other group in the study received no messages.
Participants who received messages showed increased perceptions of the necessity of preventer medication. They also accepted the long-term nature of their asthma more readily, and improved their perceived control over their asthma. 37% of the text message group took over 80% of prescribed inhaler doses compared to 23.9% in the control group.
Supportive care for medical patients has transformed in the past decade from a physician-managed care system to a guided self-management system. Many self-guided programs have been developed to provide support to individuals with a variety of medical and emotional issues. Patients find the programs satisfying for a variety of reasons including convenience, low cost and up-to-date recommendations. Asthma support programs have also enjoyed success but the cost of Internet-based asthma self-management support compared with usual care, had not been evaluated before a recent study. The report found that the quality of care and the cost of care was similar between the Internet group and traditional supportive care.
Bronchiectasis – the airway widens and causes air hunger and other signs of asthma. Chest scans show a thickening bronchial wall.
Chronic Obstructive Pulmonary disease (COPD) – shortness of breath, wheezing and coughing is common. Symptoms do not respond to bronchodilator treatment.
Cystic fibrosis – patients have a chronic cough, nasal polyps before 12 years old, and signs of internal organ deficiencies related to digestion, excretion and deficits in growth and vitality.
Foreign body aspiration – an object or particulate may lodge in the airway causing wheezing and lung collapse.
Rhinosinusitis – patients have air hunger, nighttime cough and nasal deficiencies. Nasal tests show inflammation and polyps. This condition may occur with asthma.
Tracheomalacia – usually presents itself in the first year of a child’s life. Coughing, wheezing, holding the breath, respiratory infections and cardiac problems may occur when the child is in different positions.
Vascular ring – air hunger and a high-pitched wheezing sound is indicative of heart and lung issues.
Vocal cord dysfunction – if steroid treatment does not help the asthma patient, then this condition may be to blame as the symptoms for asthma and this condition appear to be the same. A direct look at the vocal cords when the patient is having an episode can confirm diagnosis.
- Guidelines for the Diagnosis and Management of Asthma (EPR-3), July 2007, National Heart Blood Lung Institute (http://www.nhlbi.nih.gov/guidelines/asthma/)
- Diagnosis and Management of Work-Related Asthma, September 2008, American College of Chest Physicians (http://www.chestnet.org/accp/consensus-statements/diagnosis-and-management-work-related-asthma)
- Poorly controlled asthma costly, National Jewish Health (2011, August 4). (http://www.nationaljewish.org/programs/directory/asthma/)
- The Association of Health Insurance and Disease Impairment with Reported Asthma Prevalence in U.S. Children, Health Serv Res. 2011 Oct 27 (http://www.ncbi.nlm.nih.gov/pubmed/22091849)
- Young people with asthma run a greater risk of developing caries, University of Gothenburg (2011, January 11). (http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=20409196)
- Why does flu trigger asthma?, Children’s Hospital Boston (2011, May 29). (http://www.nature.com/ni/journal/v12/n7/full/ni.2045.html)
- Sleep quality and asthma control and quality of life in non-severe and severe asthma.(Sleep Breath. 2011 Nov 20)
- Persistent asthma has an accumulative impact on the loss of smell in patients with nasal polyposis.(Rhinology. 2011 15 1;49(5):519-524)
- ‘Belly fat’ linked to development of asthma European Lung Foundation (2011, September 25). (http://www.eurekalert.org/pub_releases/2011-09/elf-f092311.php)
- Early antibiotic use can lead to increased risk of childhood asthma, The Norwegian University of Science and Technology (NTNU) (2011, January 27). (http://aje.oxfordjournals.org/content/173/3/310)
- Patient Characteristics Associated with Medication Adherence, Clin Med Res. 2011 Nov;9(3-4):158 (http://www.ncbi.nlm.nih.gov/pubmed/22090568)
- Alternative therapies may leave asthmatics gasping, University of Montreal (2010, November 30).(http://www.pulsus.com/journals/abstract.jsp?origPg=abstract.jsp&sCurrPg=journal&jnlKy=4&atlKy=9632&isuKy=931&spage=1&isArt=t&&HCtype=Physician)
- A text message programme designed to modify patients’ illness and treatment beliefs improves self-reported adherence to asthma preventer medication, Br J Health Psychol. 2011 Jun 22. (http://www.ncbi.nlm.nih.gov/pubmed/22107110)
- Cost-Effectiveness of Internet-Based Self-Management Compared with Usual Care in Asthma, PLoS One. 2011;6(11):e27108. Epub 2011 Nov 11.(http://www.ncbi.nlm.nih.gov/pubmed/22096523)