ASTHMA; cause, risk factors, manifestations and management

A power point presentation on Asthma and its management

1. ASTHMA

2. Source: Leader, D. (2020). Bronchodilator or Steroid Inhaler: Which Should I Use First? Asthma Treatment

3. Introduction Asthma is a chronic inflammatory disease of the airways. It causes airway hyper-responsiveness, mucosal edema and mucus production ( Enilari & Sinha, 2019). The inflammation results in recurring episodes of symptoms. Patients experience symptom-free periods alternating with acute exacerbations. Characterized by wheezing sounds, cough, chest tightness and dyspnea. The condition is reversible, either spontaneously or with treatment

4. Predisposing Factors Allergy is the major predisposing factor of asthma. Allergy from seasonal allergens such as pollen and perennial allergens such as dust and animal dander. A irway irritants such as cold, smoke and strong perfumes trigger asthma symptoms in asthmatic patients. Other risk factors include smoking, and chronic exposure to airway irritants.

5. Etiology Viral respiratory tract infections Chronic rhinitis and sinusitis Environmental allergens Environmental pollutants Cigarrette smoking Occupational exposure Obesity and GERD Emotional stress

6. Epidemiology Asthma is an epidemic chronic condition. It is r anked 16 th among the leading causes of years lived with disability. Approximately 15 years of asthma associated disability-adjusted years are lost annually. It affects approximately 334 million people worldwide with approximately 250000 deaths annually. The condition is common across all age-groups, gender, races and socioeconomic classes. Prevalence of asthma ranges between 15-20% in many countries.

7. Epidemiology cont ’’ The prevalence is higher in industrialized countries including Canada, Germany and New Zealand. The high prevalence is associated with urbanization, air pollution, exposure to environmental allergens and passive smoking. In the US, the prevalence of asthma among adults is approximately 7.6% (Enilari & Sinha, 2019). In 2019, the CDC weighted approximately 20 million US adult citizens with asthma (CDC, 2019). The prevalence varies across ethnic groups. It is 9.1% among Black Non-Hispanics, 13.6 % Puerto Ricans and 5% among Mexicans and Asians.

8. Epidemiology Cont ’’ Asthma-caused mortality is higher in developing countries. Source : global Asthma Network (2018)

9. Pathophysiology The mechanisms responsible for asthma obstructive symptoms include; Inflammation and edema of the airway mucus membranes Accumulation of tenacious mucus secretions and Spasm of bronchi and bronchiole smooth muscles. The pathophysiology is complex and involves the following processes; Airway inflammation Intermittent airflow obstruction and Hyper responsiveness of the bronchuss

10. Pathophysiology Cont ’’ The pathophysiology occurs in two phases; the early and late phase. IgE antibodies sensitized and released by plasma cells initiate the early phase in response to environmental triggers. Upon inhalation of airway irritants, the mast cells release cytokines including histamine, prostaglandins and leukotrienes ( Sinyor & Perez, 2021). The cytokines contract the smooth muscle and cause airway tightening. Th2 lymphocytes produce interleukins, IL-4, IL-5, and IL-13 that mediate and sustain inflammation.

11. Pathophysiology cont ’’ IL-13 mediate remodeling, fibrosis and hyperplasia of the airway. The late phase occurs after several hours. Esinophils , neutrophils, basophils, helper and memory T-cells localize to the airways causing bronchoconstriction, inflammation and edema. I nflammation and bronchoconstriction result in intermittent airflow obstruction and in return increased labor during breathing. Increased histamine release from mast cells and increased smooth muscle contractility cause airway hyperresponsiveness .

12. Pathophysiology Cont ’’ The release of cytokines also cause plasma exudation and expression of mucin resulting in mucous hypersecretion. Mucus hypersecretion cause further airway obstruction and contribute to hyperresponsiveness . The mechanisms alter lungs compliance and increase breathing labor. They make the myofibroblasts cause an increase in airway epithelium and in return narrowing the smooth muscle layer. The bronchioles are unable to expand on inspiration and contract on expiration.

13. Pathophysiology Cont ’’ The increased airway resistance cause forced expiration through the narrow lumen. This causes trapping of air in the lungs. Increased air volume in lungs make patients struggle to inspire sufficient air. Expenditure of energy in breathing results in fatigue, reduced respiratory effectiveness and increased oxygen consumption. Inspiration on high lung volumes cause alveoli hyperinflation, decreased ventilation, carbon iv oxide retention, hypoxemia, and respiratory acidosis ( Sinyor & Perez, 2021).

14. source : Morris, M. (2020). Asthma. Pulmonology.

15. Clinical Presentation Patients present with the classical signs including; Wheezing sounds as air is forced out through the narrowed airways Cough with or without mucus chest tightness and Dyspnea Diaphoresis and tachycardia from labored breathing . Central cyanosis due to hypoxemia On examination, chest hyper resonance, crackles and prolonged expiration. The symptoms are often worse at night or early in the morning The clinical symptoms are then classified into intermittent, mild, moderate, and severe stages depending on their severity.

16. Source: Morris., M. (2020). Asthma guidelines. Pulmonology .

17. Prevention Measures Primary prevention involves reducing exposure to risk factors among populations at risk. It entails; Removal of allergens from indoor environment. Smoking cessation programs Mass education about possible risk factors Reduction of occupational and environmental exposure to allergens and irritants (CDC, 2020). Health weight control

18. Prevention Measures Cont ’’ Secondary prevention seeks to prevent development of the disease among sensitized individuals through. Prompt treatment of sinusitis and rhinitis Adherence to asthma medications Pneumococcal and influenza vaccinations Treating concurrent diseases In tertiary prevention, chronically-ill patients are protected from complications to prevent disease burden. It includes social support programs

19. Therapeutic Measures Pharmacologic treatment includes use of; Inhaled corticosteroids Long-acting bronchodilators (beta-2 agonists) Theophyliine Leukotriene modifiers and antileukotrienes IgE antibodies Systemic corticosteroids and anticholinergics (CDC, 2020). Oxygen supplementation to relieve hypoxemia Allergen immunotherapy Bronchial thermoplasty in medication resistant cases Intubation in severe cases causing respiratory failure

20. Research on Asthma Current research seeks to; understand the role of immune system in asthma. Role of genes in controlling immune response Introduce new treatment methods to replace use of corticosteroids Research on new treatment methods suggest that dupilumab is a potential effective treatment in place of corticostreroids ( Cevhertas et al., 2020). Currently, researchers are evaluating whether asthma is a potential risk factor for COVID-19 and its impact in management of the viral infection.

21. Impact of Asthma among adults Asthma causes morbidity and mortality especially in developing countries. It is a cause of increased hospitalizations. It impacts the quality of life factors including work, physical, social, and emotional health. Asthmatic attacks make adults miss work subjecting them reduced income or job loss. It increases healthcare usage and financial challenges related to treatment strategies. Lowered quality of life subject adult patents to depression.

22. References Enilari, O. & Sinha, S. (2019). The global impact of asthma in adult populations. Annal Global Health , 85(1), 2, https://dx.doi.org/10.5334%2Faogh.2412 Centre for Disease Control and Prevention (CDC). (2019). Most recent national asthma data. https://www.cdc.gov/asthma/most_recent_national_asthma_data.htm Cevhertas, L., Ogulur , I., Maurer, D., Burla , D., Ding, M., Jansen, K., Koch, J. & Ma, S. (2020). Advances and recent developments in asthma in 2020. Allergy , 75(12), 3124-3146, https://doi.org/10.1111/all.14607

23. References Cont ’’ Centers for Disease Control and Prevention (CDC). (2020). Asthma Prevention and Treatment. The National Institute for Occupational Safety and Health, https ://www.cdc.gov/niosh/topics/asthma/treatment.html Sinyor, B. & Perez, L. (2021). Pathophysiology of asthma. Stat Pearls , https://www.ncbi.nlm.nih.gov/books/NBK551579/ Morris, M. (2020). Asthma. Pulmonology. https:// emedicine.medscape.com/article/296301-overview Leader, D. (2020). Bronchodilator or Steroid Inhaler: Which Should I Use First? Asthma Treatment