Table 2.
Phenotypic classification of obesity-related asthma
| Phenotype | Characteristics | Predominant mechanisms | Biomarkers | Treatment response | Demographics |
|---|---|---|---|---|---|
| Atopic obesity-related asthma |
• Early onset (childhood/adolescence) • Allergic sensitization present • Eosinophilic airway inflammation • Positive allergy testing |
• Th2-mediated inflammation • Amplified allergic responses • Mechanical effects of obesity |
↑ IgE ↑ Eosinophils ↑ FeNO Positive skin prick tests | Good ICS response Standard therapy effective Anti-IgE biologics helpful | Both genders equally affected; Children and adults |
| Insulin-resistant phenotype |
• later-onset disease (typically after age 12) • Hyperinsulinemia present • Glucose intolerance or impaired glucose metabolism • Metabolic syndrome features |
• Insulin-mediated airway hyperreactivity • Non-Th2 inflammatory pathways • Metabolic dysfunction |
↑ Insulin levels ↑ HOMA-IR Impaired glucose tolerance Normal/low eosinophils | Poor ICS response May benefit from insulin sensitizers Weight loss crucial | later-onset disease (typically after age 12) |
| Dyslipidemic phenotype |
• Adult onset (typically > 30 years) • Elevated lipid levels • Male predominance (significant finding) • Often with metabolic syndrome |
• Metabolic inflammatory derangement • Oxidative stress pathways • Non-Th2 mediated inflammation |
↑ LDL cholesterol ↑ Triglycerides Dyslipidemia panel Variable eosinophils | Variable ICS response Lipid management may help Weight reduction beneficial | Predominantly males; Adult population |
| Non-Th2 neutrophilic phenotype |
• Late onset (adult) • Severe symptoms and frequent exacerbations • Poor asthma control • Neutrophilic sputum |
• Neutrophilic airway inflammation • Systemic inflammatory state • Mechanical respiratory restriction |
↑ Neutrophils ↑ Systemic inflammatory markers Low eosinophils Low/normal FeNO | Poor ICS response High-dose ICS may be needed May need IL-17 or other biologics | Adults; Both genders affected |
Th2 = T-helper type 2; IgE = Immunoglobulin E; FeNO = Fractional Exhaled Nitric Oxide; ICS = Inhaled Corticosteroids; HOMA-IR = Homeostatic Model Assessment for Insulin Resistance; LDL = Low-Density Lipoprotein; IL-17 = Interleukin-17