Table. 3—

Odds ratios (OR) of having chronic respiratory symptoms at the time of the first annual visit following a 25% decrease in cigarettes per day between baseline and the first annual visit

Participants with the symptoms at baselineParticipants without the symptoms at baseline
BaselineRetainedOR95% CIBaselineGainedOR95% CI
Cough859 (43)667 (78)0.900.79–1.041117 (57)348 (31)0.92*0.85–1.00
Phlegm736 (37)514 (70)0.83*0.79–1.041240 (63)323 (26)0.970.90–1.05
Increased cough and phlegm#580 (29)390 (67)0.870.75–1.011396 (71)314 (22)0.960.88–1.04
Wheeze1511 (76)1270 (84)0.920.82–1.03465 (24)141 (30)0.970.87–1.07
Shortness of breath841 (43)570 (68)0.990.90–1.101096 (57)235 (21)0.940.85–1.04
  • Data are presented as n (%), unless otherwise stated. CI: confidence interval. #: multiple sustained periods of increased cough and phlegm indicative of chronic bronchitis.*: p<0.05 logistic regression.