The Effects of Aging on Exhaled Nitric Oxide (FeNO) in a North African Population.

OBJECTIVE: To determine and explain the effect of age on exhaled nitric oxide values in North African healthy subjects aged from 5 to 83 years.

DESIGN: Prospective cross-sectional study.

METHODS: Volunteer children adults and elderly healthy subjects were included. A medical questionnaire was used to assess several subject characteristics. The levels of exhaled fraction of nitric oxide (FeNO) were measured by Medisoft HypAir FeNO method. Spirometry function test was done after the FeNO measurement. The following parameters were measured: forced vital capacity (FVC, L); 1st second forced expiratory volume (FEV1 , L); FEV1 /FVC ratio (absolute value); maximal mid expiratory flow (MMEF, L/s); Mid expiratory flow from 25 to 75% (MEF25%, MEF50%, and MEF75%). Statistical analyses were carried out using Statistica software with a significance set at the 0.05 level.

RESULTS: A significant increase in FeNO is noted between groups with respective age ranges of (5, 17) and (17, 25) years with a breakpoint at 1,397,034 years. A significant decrease of FeNO is noted between groups with respective age ranges of (45, 55) and (55, 65) years with a breakpoint at 6,366,052 years. No statistical significant difference was found between females' and males' means FeNO data. Finally, SEL, obesity status, and hypertension contribute significantly in the variations of FeNO values.

CONCLUSION: The development and aging of the lung touched non-respiratory functions and so modified FeNO values in healthy North African subjects.