title: Lower airway obstruction, bronchial hyperresponsiveness, and primary pulmonary hypertension in children.
abstract: We investigated the prevalence and reversibility of lower airway obstruction (LAO) and its correlation with pulmonary artery pressure in children with primary pulmonary hypertension (PPH). The analysis was performed retrospectively in a cohort of children with PPH between 5-18 years of age. PPH was defined as mean pulmonary artery pressure (PAPm) >25 mmHg at rest, or >30 mmHg during exercise, with normal pulmonary capillary wedge pressure in the absence of other causes. Lower airway function was assessed by spirometry and maximal expiratory flow-volume curves. Lung volumes were measured by body plethysmography. Patients were assigned according to their pattern of lung function into "normal," "obstructive," and "restrictive" groups. The reversibility of LAO was defined as an increase of > or = 15% from baseline in forced expiratory volume at 1 sec (FEV1) and/or > or =20% in forced expiratory flow at 25-75% of forced vital capacity (FEF25-75%) in response to nebulized albuterol. An "obstructive" pattern was found in 23 children (59%), a "restrictive" pattern in 2 children (5%), and a "normal" pattern in 14 children (36%). Response to bronchodilator was documented in 78% of children with an "obstructive" pattern and in 22% of those with a "normal" pattern. The PAPm showed a significant positive correlation with the TLC, RV, and RV/TLC, but a negative one with the ratio FEV1/FVC. Our findings suggest that reversible LAO is the most common lung function abnormality among pediatric patients with PPH. Whether airway reactivity is a cause of or the result of PPH remains to be determined.
authors.affiliation: Division of Pediatric Pulmonology, Department of Pediatrics, College of Physicians and Surgeons of Columbia University and the Morgan Stanley Children's Hospital of New York-Presbyterian, New York, New York 10032, USA.
authors.forename: Deepa
authors.initials: D
authors.lastname: Rastogi
authors.forename: Pakkay
authors.initials: P
authors.lastname: Ngai
authors.forename: Robyn J
authors.initials: RJ
authors.lastname: Barst
authors.forename: Anastassios C
authors.initials: AC
authors.lastname: Koumbourlis
mesh_terms: D000293:Adolescent; D000402:Airway Obstruction / Q000150:complications / Q000503:physiopathology*; D001794:Blood Pressure; D016535:Bronchial Hyperreactivity / Q000150:complications / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications / Q000503:physiopathology*; D008297:Male; D010993:Plethysmography, Whole Body; D011651:Pulmonary Artery; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D013147:Spirometry