title: Diurnal variability of peak expiratory flow.
abstract: Diurnal variation in peak expiratory flow (PEFvar) has been suggested as a surrogate for bronchial hyperreactivity, and may be a useful tool in the management of bronchial asthma. Several indices have been postulated to measure PEFvar; however, the number of daily measurements and the timing of recordings are not clearly established. Although several investigators have defined ranges for PEFvar in healthy individuals, clear cutoff values that differentiate asthmatics from others are not available. Despite this shortcoming, PEFvar is an important measurement in screening and diagnosis of asthma in population-based studies, as well as for assessing disease severity and prognosis. Treatment of asthma with either inhaled corticosteroids or bronchodilators may influence the magnitude of PEFvar in a complex fashion. Therefore, PEFvar should only be interpreted in conjunction with other clinical and laboratory information.
authors.affiliation: Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India. skjindal@i91.net.in
authors.forename: Surinder K
authors.initials: SK
authors.lastname: Jindal
authors.forename: Ashutosh N
authors.initials: AN
authors.lastname: Aggarwal
authors.forename: Dheeraj
authors.initials: D
authors.lastname: Gupta
mesh_terms: D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use; D000375:Aging / Q000502:physiology; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy; D016535:Bronchial Hyperreactivity / Q000175:diagnosis; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use; D002940:Circadian Rhythm; D006801:Humans; D008403:Mass Screening; D010366:Peak Expiratory Flow Rate / Q000187:drug effects; D011379:Prognosis; D012720:Severity of Illness Index
chemical_list: D000305:Adrenal Cortex Hormones; D001993:Bronchodilator Agents