Inhaled Corticosteroids (ICS)

Inhaled Corticosteroids (ICS) in Pediatric Asthma Management

Inhaled corticosteroids (ICS) are the cornerstone of asthma management in children. They are the most effective anti-inflammatory medications available for the treatment of persistent asthma across all age groups in pediatrics.

Key Points:

First-line therapy for persistent asthma in children of all ages
Reduce airway inflammation, hyperresponsiveness, and remodeling
Improve lung function, reduce symptoms, and decrease exacerbations
Generally well-tolerated with minimal systemic effects at recommended doses
Regular use is critical for maintaining asthma control

Mechanism of Action

Inhaled corticosteroids exert their effects through multiple mechanisms:

Anti-inflammatory action: ICS suppress inflammation by:
- Inhibiting the production of pro-inflammatory cytokines
- Reducing the recruitment and activation of inflammatory cells (e.g., eosinophils, T-lymphocytes)
- Decreasing vascular permeability and mucus secretion
Genomic effects: ICS bind to cytoplasmic glucocorticoid receptors, which then:
- Translocate to the nucleus
- Bind to glucocorticoid response elements (GREs)
- Upregulate anti-inflammatory genes and downregulate pro-inflammatory genes
Non-genomic effects: Rapid actions occurring within minutes, including:
- Vasoconstriction
- Reduction in vascular permeability
- Inhibition of arachidonic acid release
Airway remodeling: Long-term use may help prevent or reverse structural changes in the airways by:
- Reducing subepithelial fibrosis
- Decreasing airway smooth muscle hypertrophy and hyperplasia
- Inhibiting angiogenesis

Indications

Inhaled corticosteroids are indicated for:

Persistent asthma: First-line controller therapy for children of all ages with persistent asthma symptoms
Exercise-induced bronchospasm: Regular use can reduce the frequency and severity of exercise-induced symptoms
Acute asthma exacerbations: High-dose ICS may be used in conjunction with systemic corticosteroids in some acute settings
Seasonal allergic asthma: Prophylactic use during known trigger seasons

Specific indications by age group:

Infants and young children (0-4 years): Consider for recurrent wheezing and risk factors for persistent asthma
School-age children (5-11 years): Recommended for persistent asthma of any severity
Adolescents (12+ years): Similar indications as adults, with consideration for growth effects

Dosing and Administration

Common ICS Agents and Formulations:

Fluticasone propionate (MDI, DPI)
Budesonide (DPI, nebulizer suspension)
Beclomethasone dipropionate (MDI)
Mometasone furoate (DPI)
Ciclesonide (MDI)

Dosing Considerations:

Age-based dosing: Adjust doses based on the child's age and ability to use different delivery devices
Severity-based dosing: Categorized as low, medium, and high doses based on asthma severity
Step-up approach: Start at the lowest effective dose and increase as needed to achieve control
Step-down strategy: Gradually reduce dose once asthma is well-controlled for 3-6 months

Administration Tips:

Use spacer devices with MDIs to improve drug delivery, especially in younger children
Teach and regularly review proper inhaler technique
Rinse mouth after use to reduce the risk of oral thrush
Consider nebulized formulations for infants and young children who cannot use inhalers effectively

Efficacy

Inhaled corticosteroids have demonstrated high efficacy in pediatric asthma management:

Symptom control: Significant reduction in day and night symptoms
Lung function: Improvement in FEV1 and peak expiratory flow
Exacerbation reduction: Decreased frequency and severity of asthma exacerbations
Rescue medication use: Reduced need for short-acting beta-agonists
Quality of life: Improved overall quality of life and reduced school absenteeism
Airway hyperresponsiveness: Decreased bronchial hyperreactivity

Comparative Efficacy:

Generally, ICS are more effective than leukotriene receptor antagonists (LTRAs) for asthma control
Low-dose ICS is usually more effective than high-dose LTRA in children with mild persistent asthma
Different ICS agents have similar efficacy when compared at equivalent doses

Factors Affecting Efficacy:

Adherence to prescribed regimen
Correct inhaler technique
Use of appropriate spacer devices
Individual responsiveness to ICS (may vary among patients)

Safety Profile

Inhaled corticosteroids have a favorable safety profile when used at recommended doses:

Local Side Effects:

Oral thrush (candidiasis): Can be minimized by using spacer devices and rinsing mouth after use
Dysphonia: Usually mild and reversible
Cough and throat irritation: More common with DPIs

Systemic Side Effects:

Growth:
- Potential for mild growth suppression (about 1 cm/year) in first 1-2 years of treatment
- Effect is usually temporary and dose-dependent
- No significant impact on final adult height in most studies
Bone health:
- No significant effect on bone mineral density at recommended doses
- Importance of adequate calcium and vitamin D intake
Adrenal suppression:
- Rare at standard doses
- More likely with high doses or concomitant use of other forms of corticosteroids
Ocular effects:
- No evidence of increased risk of cataracts or glaucoma at standard pediatric doses

Safety Monitoring:

Regular growth monitoring in children on long-term ICS therapy
Consideration of the lowest effective dose to maintain asthma control
Periodic reassessment of the need for continued ICS therapy

Clinical Considerations

Patient Education:

Emphasize the importance of regular use, even when asymptomatic
Teach proper inhaler technique and spacer use
Explain the difference between controller (ICS) and reliever medications
Address concerns about corticosteroid use, particularly regarding growth

Adherence Strategies:

Simplify regimen when possible (e.g., once-daily dosing)
Use combination inhalers (ICS + LABA) in appropriate cases to improve adherence
Implement reminder systems (e.g., smartphone apps, calendar alerts)
Regular follow-up to reinforce the importance of adherence

Monitoring and Follow-up:

Regularly assess asthma control using standardized tools (e.g., ACT, C-ACT)
Monitor growth and adjust treatment as needed
Consider step-down therapy once asthma is well-controlled for 3-6 months
Evaluate inhaler technique at each visit

Special Populations:

Preschool children: Consider intermittent high-dose ICS for viral-induced wheezing
Adolescents: Be aware of potential adherence issues and increased risk-taking behaviors
Athletes: Address concerns about doping regulations and potential for exercise-induced bronchoconstriction

Combination Therapy:

Consider adding long-acting beta-2 agonists (LABAs) for children ≥4 years with uncontrolled asthma on medium-dose ICS
Leukotriene receptor antagonists (LTRAs) may be used as add-on therapy or alternative to ICS in mild cases
Biologics (e.g., omalizumab, mepolizumab) for severe asthma uncontrolled with high-dose ICS and other controllers