Patients with asthma and obesity at elevated risk of mortality and increased hospitalization

The study findings were presented in a poster at the annual American Academy of Allergy, Asthma & Immunology meeting.

Obesity is a significant risk factor for asthma development and increased asthma morbidity. There is a lack of extensive epidemiological studies addressing the impact of obesity on near-fatal asthma events. Considering this, Karl Mueller, a resident at the Mayo Clinic College of Science and Medicine in Florida, and colleagues aimed to determine if obesity is a risk factor for worse outcomes in asthma patients with an exacerbation.

For this purpose, the researchers conducted a retrospective review using the National Inpatient Sample from 2005 to 2014. Cases of asthma exacerbation were identified in patients five years or older utilizing the International Classification of Diseases, Ninth Revision, Clinical Modification codes (ICD-9-CM), using ICD-9-CM 493.xx for asthma exacerbation.

Cases were uncategorized into non-obese (BMI <30) and obese (BMI >_30). A near-fatal asthma event was defined as an asthma exacerbation resulting in respiratory arrest, tracheostomy, and cardiac arrest.

Key findings of the study include:

• Among 677,591 asthma exacerbations (mean age 47.8, 66% female, 52% White, 86% Non-Hispanic), there were 18% cases with obesity, 0.14% near-fatal asthma events, and 0.37% all-cause fatal events.
• Obese patients, compared to non-obese patients, had an increased mean hospitalization (4.2 vs 3.5 days), mean total direct cost ($24,550 vs $18,973), and near-fatal asthma events (0.2% vs 0.1%).

"It's known that for patients who are cardiac risks and obese, physicians recommend they reduce their weight, or for patients who were overweight and have diabetes," Mueller said. "Now they should start thinking about asthma as one of those conditions too."

"For future research, it is important to understand the underlying causes of worse asthma exacerbations in obese patients," he said.

"Is it because they are having more obesity-related lung conditions like obesity hypoventilation syndrome or obstructed sleep apnea?" he asked. "Or is there altered immunometabolism resulting in resistance of our conventional therapies, leading to this increased risk that we're seeing?"

"Is it because they have more obesity-related lung conditions like obstructive sleep apnea or obesity hypoventilation syndrome?" he asked. "Or is there altered immunometabolism leading to resistance of our conventional therapies, leading to this increased risk that we're seeing?"

"Asthma patients with obesity are at an increased risk for near-fatal asthma events with a longer hospitalization and cost than non-obese asthma patients," the authors conclude. "Further research is warranted to identify the mechanisms underlying this increased risk."

Reference:

Mueller K, et al. Abstract #220. Presented at: AAAAI Annual Meeting; Feb. 24-27, 2023; San Antonio.