Fractional Exhaled Nitric Oxide (FENO) Is Negatively Associated with Percent-Predicted FEV1 in Inner-City Minority Asthma Patients
Sunday, March 6, 2016
South Exhibit Hall H (Convention Center)
Sherlyana Surja, MD, Byung Yu, MD, Christopher D. Codispoti, MD PhD, James N Moy, MD
Rationale: Asthma is a common disorder in African Americans (AA) and Hispanic Americans (HA). Little is known about the relationship of fractional exhaled nitric oxide (FENO) with asthma control in minority populations. We assessed the relationship of FENO with various asthma measures in our inner-city allergy clinic. 

Methods: We performed a retrospective review of medical records of asthma patients in our allergy clinic at a large, public hospital. Asthma patients who performed FENO measurements in the first month after our clinic acquired a FENO analyzer (NIOX VERO) were included.  We looked for associations between FENO and Asthma Control Test (ACT) scores, percent-predicted FEV1 (%FEV1), and asthma medications.

Results: FENO was measured in 56 patients. The patients ranged from 6 to 57 years old.  There were 26 AA children (46.5%), 18 AA adults (32%), 7 HA children (12.5%), and 5 HA adults (9%).  FENO ranged from 4 to 190 ppb.  The %FEV1 ranged from 46 to 135. FENO was negatively associated with both the pre and post-albuterol %FEV1 (r2=0.269, p=0.0001, and r2=0.1813, p=0.001, respectively). The negative association between FENO and pre-albuterol %FEV1 was stronger in adults (r2=0.403, p=0.001) than in children (r2=0.150, p=0.026).  In adult patients with %FEV1<80, FENO was higher (67.3±14.5ppb) compared to adults with %FEV1≥80 (22.9±5.5ppb, p=0.005). FENO was not associated with ACT score or asthma medications.

Conclusions:  In our inner-city minority asthma patients, elevated FENO is associated with lower lung function; a measure of asthma severity.  Our findings extend previously reported results of the general population to an inner-city minority asthma population.