Table 2

Temporal transitions in selected study population characteristics and FeNO levels

VariableYears 5–6 transition categoriesN (%)GM of year 5 FeNO (GSD)*p ValueMean of FeNO change (SD)p Value
SeasonWarm–Warm226 (18.7)15.9 (16.6)0.162.5 (11.7)0.33
Cold–Warm368 (30.4)14.1 (15.9)1.1 (12.0)
Warm–Cold213 (17.6)15.6 (16.9)1.1 (12.9)
Cold–Cold404 (33.4)16.9 (18.8)0.5 (14.7)
AsthmaNo Asthma–No Asthma1052 (86.9)14.5 (14.8)<0.011.4 (12.4)0.07
No Asthma–Asthma23 (1.9)27.7 (40.3)−4.2 (27.6)
Asthma–Asthma136 (11.2)22.3 (25.0)0.01 (14.6)
AllergyNo Allergy–No Allergy441 (36.4)13.0 (12.7)<0.010.8 (10.7)0.54
No Allergy–Allergy44 (3.6)13.3 (8.6)3.1 (9.6)
Allergy–Allergy726 (59.9)17.3 (19.7)1.2 (14.5)
Secondhand smokingNo SHS–No SHS1128 (93.15)15.4 (16.5)0.111.4 (12.5)0.04
(SHS)No SHS–SHS20 (1.65)24.6 (43.2)−3.2 (28.6)
SHS–No SHS26 (2.15)15.7 (11.7)−2.9 (6.8)
SHS–SHS13 (1.07)19.2 (27.4)−5.5 (27.8)
  • *Results based on geometric means (GM) and geometric SDs (GSD) due to skewness of year 5 FeNO data.