Exhaled nitric oxide: A novel biomarker of adverse respiratory health effects in epidemiological studies

The sampling of exhaled breath is a noninvasive procedure that can be perfo rmed easily in adults, children, and patients with respiratory disease. Sev eral studies have demonstrated increased exhaled nitric oxide in patients w ith pulmonary disease, including asthma. In addition, exhaled nitric oxide may be an elegant tool for monitoring of environmental health effects of ai r pollution and the prevalence of atopy in epidemiological surveys. Recent literature about exhaled nitric oxide is presented in this article. Technic al, physiological, and behavioral confounding factors of exhaled nitric oxi de measurement are outlined.