Jacob et al. [58] identified patients with persistent asthma by using medication claims for long-acting β-2 agonists (LABA), leukotriene modifiers (LTRA), inhaled corticosteroids, oral corticosteroids, Anti-IgE, theophylline, and ipratropium bromide in combination with hospitalisations with a primary diagnosis of asthma. Here, IGHE is linked to asthma.