Figures
- Fig. 1—
Bronchodilator (BD) responses in the special intervention (•) and usual care (○) groups over 11 yrs. a) shows relative responses, b) shows absolute responses, and c) shows responses as a percentage of predicted. #: significant differences among groups.
- Fig. 2—
Bronchodilator (BD) responses as a function of time in sustained quitters (○), intermittent quitters (▓), and continuing smokers (•). a) shows relative responses, b) shows absolute responses, and c) shows responses as a percentage of predicted. #: significant differences among groups.
- Fig. 3—
Frequency distribution of root mean squared error (RMSE), an analog of the standard deviation, of absolute response for years one to five.
Tables
- Table. 1—
Baseline data: 11-yr cohort
Variable Male 61.9 Age yr 50.1±7.4 SI treatment group 67.2 Baseline cigarettes·day−1 30.8±12.7 Pack-yrs 39.9±18.6 LHS 3 smoking status Sustained quitters 17.7 Intermittent quitters 57.1 Continuous smokers 25.5 FEV1 Pre-BD L 2.64±0.60 Post-BD L 2.75±0.63 FEV1 % pred pre-BD 75.4±8.73 % pred post-BD 78.5±9.01 Methacholine reactivity 5 mg·mL−1 % reactors# 33.6 25 mg·mL−1 % reactors# 71.8 Data are presented as mean±sd or %. SI: special intervention; LHS: lung health study; FEV1: forced expiratory volume in one second; BD: bronchodilator. #: reactors showed a decline in FEV1 of ≤20% in response to the indicated (or lower) doses.
- Table. 2—
Bronchodilator response by demographic variables
Variable Absolute Relative % predicted Response p-value Response p-value Response p-value Sex Females 86.6 <0.001# 4.20 0.308# 3.07 0.299# Males 127.3 4.36 3.19 Group SI 112.2 0.776# 4.33 0.534# 3.16 0.543# UC 111.0 4.23 3.09 LHS 3 smoking status SQ 116.0 0.519# 4.41 0.712# 3.23 0.601# IQ 111.8 4.30 3.15 CS 108.9 4.21 3.06 Methacholine Reactivity No response 107.1 <0.001# 3.62 <0.001# 2.82 <0.001# 25 mg 103.6 3.70 2.79 10 mg 109.7 4.30 3.12 5 mg 115.6 4.82 3.41 1 mg 151.3 6.73 4.57 Diluent 93.8 4.55 3.02 Age −0.200¶ <0.001+ −0.134¶ <0.001+ −0.157¶ <0.001+ Baseline cigarettes·day−1 −0.032¶ 0.013+ −0.044¶ 0.001+ −0.057¶ <0.001+ Pack-yrs −0.108¶ <0.001+ −0.089¶ <0.001+ −0.109¶ <0.001+ SI: special intervention; UC: usual care; LHS: lung health study; SQ: sustained quitters; IQ: intermediate quitters; CS: continuous smokers. #: p-value for ANOVA test of response differences within groups; ¶: correlation; +: p-value for correlation of response by variable of interest.
- Table. 3—
Comparison of bronchodilator response and methacholine reactivity
Bronchodilator response Methacholine reactivity Sex difference No Yes Age related Yes No Related to baseline smoking Yes No Influence of smoking cessation Increases Decreases Effect of disease progression Increases Increases Predicts decline of FEV1 No Yes FEV1: forced expiration volume in one second.
