Table 4– Characteristics at enrolment of patients for which comparisons led to p-values <0.10 with and without pathogens
CharacteristicsITT with pathogensITT without pathogensp-value#
Subjects n662690
Age group yrs0.0003
 ≥75167 (25.2)147 (22.9)
 <75495 (74.8)495 (77.1)
Alcohol use0.046
 Abstinent415 (62.7)453 (65.8)
 Light consumption222 (33.5)196 (28.4)
 Moderate consumption25 (3.8)40 (5.8)
Sex0.064
 Male542 (81.9)537 (77.9)
 Female120 (18.1)152 (22.0)
FEV1 at enrolment % pred0.021
 <30149 (22.6)190 (27.6)
 ≥30510 (77.4)498 (72.4)
Diabetes0.095
 Yes80 (12.1)64 (9.3)
 No582 (87.9)626 (90.7)
Cardiopulmonary disease0.011
 Yes92 (13.9)65 (9.4)
 No570 (86.1)625 (90.6)
Respiratory disease0.070
 Yes134 (20.2)168 (24.3)
 No528 (79.8)522 (75.7)
History of respiratory failure0.035
 Yes59 (8.9)86 (12.5)
 No603 (91.1)603 (87.5)
Short-acting anticholinergics0.015
 Yes95 (14.3)69 (10.0)
 No567 (85.7)621 (90.0)
Short-acting bronchodilator0.080
 Yes153 (23.1)188 (27.2)
 No509 (76.9)502 (72.8)
Previous antibiotic use0.021
 Yes206 (31.1)256 (37.1)
 No456 (68.9)434 (62.9)
Exacerbation in last 3 months0.069
 Yes335 (50.6)315 (45.6)
 No327 (49.4)375 (54.3)
Chest discomfort at baseline0.020
 Absent551 (83.6)604 (88.0)
 Present108 (16.4)82 (12.0)
Wheeze at baseline0.047
 Absent409 (62.2)462 (67.3)
 Present249 (37.8)224 (32.7)
Sputum viscosity at baseline0.015
 Liquid24 (3.6)22 (3.2)
 Thick409 (61.9)401 (58.1)
 Very thick84 (12.7)67 (9.7)
 Quite thick144 (21.8)200 (29.0)
Wheeze at exacerbation0.033
 Absent109 (42.9)145 (21.0)
 Present552 (50.4)544 (79.0)
AECB-SS phlegm colour0.021
 Clear/white/grey70 (11.9)76 (12.2)
 Yellow318 (54.2)382 (61.1)
 Green/brown199 (33.9)167 (26.7)
AECB-SS at exacerbation: disturbances in daily activities0.089
 Not at all/slightly211 (35.9)191 (30.5)
 Moderately173 (29.4)214 (34.1)
 A lot/extremely204 (34.7)222 (35.4)
  • Data are presented as n (%) unless otherwise stated. ITT: intent-to-treat; FEV1: forced expiratory volume in 1 s; % pred: % predicted; AECB-SS: Acute Exacerbation of Chronic Bronchitis Symptom Score. #: p-values from the Wald Chi-squared statistic; : any antimicrobial given for any indication between 30 and 90 days prior to enrolment.