Respiratory Diseases: Asthma And COPD Flashcards
Define Childhood Asthma
Chronic disease associated with recurrent episodes of (reversible) airways obstruction manifesting as symptons of shortness of breath, wheeze and cough
Describe the difference between a normal airway and one during asthma symptoms
- Normal airway: outer layer is muscle within an inner airway wall, centre is open for airflow
- Asthma airway: Outer layer is muscle within a thickened inner airway wall followed by mucus in the centre
Describe the estimated asthma prevalence
- > 10.1 in coastal countries (America, Canada, Brazil, Australia, UK)
- 7.6-10.0 in South Africa, Finland etc
- 5.1-7.5 in Iran, Saudi Arabia, France, Germany
- 2.5-5.0 in Mexico, Morocco, Algeria, Pakistan, India
- 0-2.5 in Russia, China
Describe the temporal trends in asthma deaths and hospitalisations in Ecuador between 2000-2019
- Hospitalisation rate drops slowly between 2001 and 2011 (24.5 - 22.5)
- Sharper steady drop between 2011 and 2018 (22.5 - 14)
Describe the temporal trends in asthma deaths and hospitalisations in Ecuador between 2000-2019
- Mortality rate was steadily dropping from 0.83 to 0.3 between 2000 and 2018
- No more data beyond, possibly due to Covid 19
Describe the world wide burden of asthma
- 262 million people suffer from asthma worldwide (GBD, 2020).
– 21.6 million DALYs in 2019
– 460,000 asthma deaths in 2019.
– Over 90% of all asthma deaths occur in low and lower-middle income countries.
List the triggers of asthma
- Exercise
- Pets
- Pollen
- Bugs in the home
- Chemical fumes
- Dust
- Smoke
- Stress
What else can cause asthma?
- Dermatophagoides pteronyssinus
- Blomia tropicalis
- Mite faeces contain allergens: Der p1, Blo t5
List the risk factors for asthma
- Parents with asthma (e.g. genetics)
- Atopy
- Childhood respiratory infections (e.g RHV and RSV)
- Early life exposures to allergens or infections while the immune system is developing
- Psychosocial stress, diet, etc
How do we measure atopy in epidemiological studies?
- Atopy
- Either allergen Skin Prick Test reactivity (SPT)
- Or allergen-specific IgE (asIgE)
What is the association between current wheeze with atopy?
- Compare an allergen skin test reactivity with an allergen specific IgE
- Measure the level of combined affluent and the combined non affluent
Describe the difference between Asthmatic children with and without rhinovirus infection
VD
How does Asthma diagnosis work?
- Based on:
- Medical history
- Physical examination
- Test results:
- Spirometry: Bronchial hyperresponsiveness, Reversibility
- Blood: Eosinophilia, Specific IgE
- Allergen skin prick test
- Fractional Exhaled nitric oxide (FeNO)
How is asthma managed?
- Medication: Quick relief (rescue) medications: Short acting beta agonists, Ipratropium (anticholinergic), Oral and intravenous corticosteroids
- Long term control: Inhaled corticosteroids, Leukotriene modifiers, Long-acting beta agonists, Combination inhalers
- Avoid triggers
Describe the stepwise approach to asthma
VD
List the issues of asthma in LMICs
- Increasing burden of disease: Urbanisation and urban risk factors, inequalities
- Access to healthcare and drugs: Under diagnosis/ poor training, use of ER for control, Affordable inhaled drugs, economic costs to family
- Different risk factors and predominant non atopic disease
Give another issue with asthma in LMICs
Urban residence is associated with a 50% greater risk of asthma than rural residence
What is Pro-AR?
WHO Demonstration project - Bahia (Brazil)
Impact of a public health intervention for management
of severe asthma on health resource utilization and costs
Describe the Programme for Control of Asthma in Bahia (ProAR)
- Reference centre for management of severe asthma by a multidisciplinary team
- Free treatment, according to guidelines
- Research programme
- A partnership between a public university (UFBA) and municipal health department
What was the impact of ProAR on hospitalisation rates in the City of Salvador?
VD
Describe the costs of severe Asthma in Salvador Brazil
- Year before: Government = $750 Families = $807
- Year after: Government = $363 Families = $74
What’s the linkage between Covid 19 and asthma?
- Several respiratory viruses strongly linked to asthma attacks
- COVID-19 does not appear to increase risk of asthma attacks
- Some evidence that adult asthmatics with severe disease have greater risk of more severe Covid-19 outcomes.
- ICS may protect against severe Covid-19 by reduction in airways inflammation and expression of ACE2
Summarise this whole asthma section
- Asthma is a common disease of childhood and adults
- Airways obstruction reversible and generally associated with inflammation
-May be allergic or non-allergic - Prevalence (was) increasing worldwide, now more in LMICs
- Respiratory viral infections frequent cause of exacerbations
- Spirometry important aid to diagnosis controlled by rescue (b2-agonist) and preventer (inhaled corticosteroids) medications
- STEP-approach to management with increase or decrease in medications according to control of symptoms
- Improved access to specialized care and treatment key to control in LMICs
