TABLE 1.

Clinical characteristics of study participants

	Asthmatic subjects, n=13	Healthy controls, n=14
Age (range), years	27.1 (18–45)	29.4 (19–51)
Sex (male/female)	7/6	9/5
FVC, L	4.3±0.9	4.8±0.8
FVC, % predicted	94.7±13.1	101.4±10.8
FEV1, L	3.3±0.7†	4.0±0.6
FEV1, % predicted	87.1±12.9†	101.0±10.3
PC20, mg/mL	2.2±2.1†	164.6±93.9
Atopy*	yes	no

Data are expressed as mean ± SEM, unless otherwise indicated.

^*Atopy was assessed using the skin prick test: response read at 10 min, a wheal response to histamine of 3 mm or greater served as a positive control, and sterile water as a negative control;

^†Statistically different from the healthy controls (P<0.01) using the Student’s t test. FEV₁ Forced expiratory volume in 1 s; FVC Forced vital capacity; PC₂₀ Provocative concentration of methacholine causing a 20% fall in FEV₁