The researchers found that patients with poorly controlled severe asthma generated significantly higher CO2 emissions (5.2% to 23.0% more) due to increased hospitalizations and overuse of rescue inhalers, particularly short-acting bronchodilators. However, when patients were referred to specialist asthma care, their carbon emissions decreased by 12.1% to 23.9%, demonstrating that better asthma management not only improves patient health but also reduces environmental impact