Table 1.

Baseline demographic and clinical characteristics of all study participants

CHARACTERISTICALL (N = 69)POSITIVE MCT RESULT (n = 21)NEGATIVE MCT RESULT (n = 48)P VALUEEFFECT SIZE (ϕ OR g)
Female sex, n (%)45 (65.2)14 (66.7)31 (64.6).8670.02
Mean (SD) age, y41.14 (16.03)38.52 (19.04)42.29 (14.59).3730.18
Mean (SD) BMI, kg/m226.60 (5.01)26.07 (5.45)26.81 (4.86).5900.14
Smoker, n (%)4 (5.8)1 (4.8)3 (6.3)> .99-0.03
Family history, n (%)22 (31.9)11 (52.4)11 (22.9).0160.29
Nasal allergy symptoms, n (%)29 (42.0)9 (42.9)20 (41.7).9270.01
Allergy history, n (%)42 (60.9)14 (66.7)28 (58.3).5140.08
Baseline symptoms, n (%)
    • Cough53 (76.8)16 (76.2)37 (77.1)> .99-0.01
    • Wheeze32 (46.4)11 (52.4)21 (43.8).5080.08
    • Shortness of breath36 (52.2)13 (61.9)23 (47.9).2840.13
    • Chest tightness31 (44.9)10 (47.6)21 (43.8).7660.04
Spirometry results, mean (SD)
    • Pre FVC, L3.60 (1.08)3.24 (0.89)3.77 (1.13).0650.49
    • Post FVC, L3.62 (1.11)3.24 (0.93)3.79 (1.15).0590.50
    • Pre FVC, %*96.32 (14.71)93.23 (13.16)97.67 (15.27).2510.30
    • Post FVC, %*96.77 (15.21)92.90 (12.07)98.46 (16.22).1650.37
    • Pre FEV1, L2.99 (0.84)2.68 (0.66)3.13 (0.88).0400.54
    • Post FEV1, L3.09 (0.87)2.77 (0.73)3.22 (0.90).0460.52
    • Pre FEV1, %*96.59 (15.02)92.02 (14.15)98.59 (15.09).0950.44
    • Post FEV1, %*99.76 (15.69)95.08 (14.35)101.80 (15.95).1020.43
    • ΔFEV1, L0.10 (0.12)0.10 (0.13)0.10 (0.12).9700.00
    • ΔFEV1, %3.22 (4.16)3.33 (4.14)3.18 (4.21).8920.04
    • Pre FEV1-FVC0.84 (0.07)0.84 (0.07)0.85 (0.07).6380.14
    • Post FEV1-FVC0.87 (0.07)0.87 (0.08)0.86 (0.06).9050.15
    • Pre FEF25-75, L/s3.28 (1.09)2.88 (0.96)3.45 (1.11).0530.53
    • Post FEF25-75, L/s3.62 (1.07)3.24 (1.08)3.78 (1.04).0580.51
  • BMI—body mass index, FEF25-75—forced expiratory flow at 25% to 75% of the pulmonary volume, FEV1—forced expiratory volume in 1 s, FVC—forced vital capacity, MCT—methacholine challenge testing, post—postbronchodilation, pre—prebronchodilation.

  • *Pre-and postbronchodilator percentages are compared to predicted values before and after bronchodilation.

  • Change in volume or percentage before and after bronchodilation.