Table 5– Adjusted change in mean standardised residual# per 10-fold increase in endotoxin level for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC and endotoxin levels for atopics and nonatopics and stratified by CD14 genotype
CD14/-260 genotypep-value
CCCTTTHeterogeneity of effectTrend of interactionTest of difference in effect of CD14 on lung function response to endotoxin+
FEV1, adjusted§
 Nonatopics0.46 (-0.03–0.96) (n=84)0.08 (-0.21–0.38) (n=191)-0.39 (-0.78– -0.01) (n=104)0.0280.0040.091
 Atopics1.11 (0.67–1.55) (n=26)-0.13 (-0.71–0.43) (n=79)0.16 (-0.67–1.00) (n=41)0.0010.273
FVC, adjusted§
 Nonatopics0.57 (0.01–1.13) (n=84)0.004 (-0.31–0.32) (n=190)-0.45 (-0.82– -0.08) (n=104)0.0080.0090.260
 Atopics0.42 (-0.35–1.20) (n=26)-0.02 (-0.59–0.55) (n=80)-0.04 (-0.82–0.73) (n=41)0.6150.900
FEV1/FVC, adjusted§
 Nonatopics-0.12 (-0.58–0.33) (n=84)0.06 (-0.20–0.33) (n=190)0.28 (-0.07–0.65) (n=104)0.3620.1940.107
 Atopics1.44 (0.60–2.27) (n=26)0.02 (-0.50–0.55) (n=80)0.31(-0.25–0.88) (n=41)0.0180.221
  • Data are presented with 95% confidence intervals. #: a male of age 50 yrs and height 180 cm is predicted to have a FEV1 of 3.8 L using the equation of Quanjer et al. [17]. If his observed FEV1 is 4 L, then the difference between observed and predicted FEV1 is 0.2 L. Following standardisation (again using the standard deviation provided by Quanjer et al. [17]), his standardised residual is 0.38. This means the difference between his measured and predicted FEV1 is 0.38 standard deviations greater than the mean of all of these values.: additive model. +: comparing atopics and nonatopics, p-value of hypothesis that a linear effect of a three-way interaction term (endotoxin×CD14/-260C to T×atopy) is equal to 0. §: confounders were age, sex, smoking status in pack-yrs and household variables (keeping a cat or dog, age of the mattress, presence of mould in bedroom, presence of damp in bedroom, household density and age of home).