What is the recommended treatment for asthma in obese individuals?

Treatment of Asthma in Obese Individuals

Weight reduction is recommended in obese patients with asthma to improve asthma control, and should be achieved through a comprehensive lifestyle intervention combining reduced-calorie diet, exercise/increased physical activity, and behavioral counseling. 1

Core Treatment Strategy

Weight Loss as Primary Intervention

• Target a 5-10% weight loss as this threshold results in clinically important improvements in asthma control in 58% of patients and quality of life improvements in 83% of patients 2
• Weight loss of 48-100% remission of asthma symptoms and medication use has been documented in obese individuals with doctor-diagnosed asthma 3
• Weight reduction improves asthma severity, reduces medication requirements, decreases dyspnea, enhances exercise tolerance, and reduces acute exacerbations including hospitalizations 3

Comprehensive Lifestyle Intervention Components

The intervention must include all three elements 1:

1. Reduced-calorie diet (especially meal substitution programs)
2. Exercise/increased physical activity (combining aerobic and resistance training)
3. Behavioral counseling and modifications

Exercise Training Specifics

• Aerobic and resistance muscle training combined produces superior outcomes compared to diet alone 4
• Exercise added to weight-loss programs achieves better clinical control scores (median improvement -0.7 vs -0.3 with diet alone, P=0.01) 4
• Exercise interventions result in greater weight loss (-6.8% vs -3.1%, P<0.001) and improved aerobic capacity (3.0 vs 0.9 ml O2/kg/min, P<0.001) 4
• Physical training improves cardiopulmonary efficiency and should be part of general lifestyle rehabilitation, with appropriate precautions for exercise-induced asthma 1

Standard Asthma Pharmacotherapy

Continue Conventional Treatment

• Inhaled corticosteroids (ICS) remain the most consistently effective long-term control medication at all steps of care for persistent asthma 1
• ICS improve asthma control more effectively than leukotriene receptor antagonists or any other single long-term control medication 1
• However, obese patients demonstrate altered, generally less favorable responses to both reliever and controller medications compared to normal-weight patients 5

Treatment Approach Philosophy

• Combine pharmacologic and non-pharmacologic therapies rather than primarily focusing on stepping up asthma therapy 5
• The obesity-related asthma phenotype has different characteristics including association with atopy and type of airway inflammation compared to classic asthma 5
• This phenotype may have a potentially higher remission rate with weight loss interventions 5

Mechanisms and Expected Outcomes

Physiologic Improvements

• Weight loss improves lung function and airway responsiveness to inhaled methacholine 3
• Reductions in gynoid adipose tissue are associated with reduced neutrophilic airway inflammation in women 2
• Reductions in dietary saturated fat are associated with reduced neutrophilic airway inflammation in males 2
• Exercise interventions specifically reduce sputum eosinophils 2

Clinical Improvements

• Asthma control improves significantly with dietary and combined interventions 2
• Quality of life improves with dietary, exercise, and combined interventions 2
• Improvements occur in antiinflammatory biomarkers, vitamin D levels, and reductions in airway and systemic inflammation 4

Comorbidity Management

Screen and Treat Associated Conditions

• Evaluate for obstructive sleep apnea, particularly in overweight/obese patients with poorly controlled asthma 1
• Assess for gastroesophageal reflux, especially in patients with frequent nighttime symptoms or poorly controlled asthma 1
• GERD treatment includes avoiding heavy meals, fried foods, caffeine, and alcohol; avoiding food/drink within 3 hours of bedtime; elevating head of bed 6-8 inches; and using proton pump inhibitors 1

Common Pitfalls to Avoid

• Do not delay weight loss interventions while only escalating asthma medications, as obese patients have diminished responses to conventional therapies 5
• Do not recommend diet alone without exercise, as the combination produces significantly better outcomes 4
• Do not expect improvements in eosinophilic airway inflammation markers (like exhaled nitric oxide), as weight loss primarily affects neutrophilic inflammation and clinical outcomes rather than eosinophilic pathways 3
• Do not overlook the distinct obesity-related asthma phenotype, which may represent a disease mimicking asthma with higher remission potential 5

Adjunctive Pharmacotherapy Considerations

• For patients unable to achieve or sustain weight loss through comprehensive lifestyle intervention, consider adjunctive pharmacotherapy if BMI ≥30 kg/m² or BMI ≥27 kg/m² with weight-related comorbidities (such as asthma), unless contraindicated 1
• Liraglutide has been studied in obese patients with moderate OSA and produced significant weight loss (mean difference -4.9 kg) 1