Measuring serum concentrations of mannitol after inhalation can potentially provide insights into airway barrier function in asthma, a new study found. Health controls and participants with mild asthma inhaled dray powder mannitol in a dose-escalating manner on 2 separate occasions, stopping at 155 mg or 315 mg. Serum mannitol levels were measured at baseline and then 30, 90, and 150 minutes after mannitol inhalation. Absorption was compared with measurements of airflow obstruction (FEV1) and airway inflammation (FeNO). Researchers found:
- In both healthy controls and subjects with asthma, serum mannitol levels increased in a time- and dose-dependent manner.
- No significant differences in mannitol absorption were observed when comparing the 2 groups.
- Mannitol absorption did not correlate with markers of airway obstruction or inflammation.
Georas S, Ransom N, Hillman S, et al. The leaky lung test: A pilot study using inhaled mannitol to measure airway barrier function in asthma. [Published online ahead of print November 16, 2018]. J Asthma. doi:10.1080/02770903.2018.1536145.