In stable, elderly, asthmatic patients, fractional exhaled nitric oxide (FENO) was not elevated and did not correlate with subject demographics, comorbidities, treatment, symptoms, or spirometric values. Researchers at the University of Pennsylvania School of Medicine in Philadelphia, followed 30 asthmatics (mean age 72) for one year with evaluation at baseline and every three months.
Following data analysis, FENO (measured in triplicate) was not elevated in subjects at baseline (18.2 +/-14.3 ppb, 5-60) and did not significantly change throughout the follow-up period. The asthma control test (ACT) score at baseline was 22.1 +/-2.8, FEV1 was 84.9 +/-20.3%. The researchers found no significant correlation between FENO and FEV1/FVC (P
>0.55, 0.25, 0.10, 0.26, respectively, at each time point), or other spirometric values, inhaled steroid dose, or ACT at any time point. Further, no associations were found between FENO and age, sex, BMI, atopic status, disease duration, presence of rhinitis or gastroesophageal reflux disease, or other medications used.
The researchers concluded that routine measurement of FENO may not be clinically valuable in elderly asthmatics.