TABLE 1.
Characteristics of study participants
| Characteristic | All patients |
Haemophilus influenzae status |
P valueb | |
|---|---|---|---|---|
| Negative | Positive | |||
| Patients (n) | 150 | 73 | 77 | |
| Age (yr) | 0.38 | |||
| Mean (SD) | 66.6 (9.6) | 67.3 (9.8) | 65.9 (9.5) | |
| Range | 45–85 | 47–85 | 45–84 | |
| Race (n [%])a | 0.57 | |||
| White | 131 (87.3) | 65 (89.0) | 66 (85.7) | |
| Nonwhite | 18 (12.0) | 8 (11.0) | 10 (13.0) | |
| Sex (n [%]) | 0.16 | |||
| Male | 148 (98.7) | 73 (100) | 75 (97.4) | |
| Female | 2 (1.3) | 0 | 2 (2.6) | |
| Current smoker (n [%]) | 0.10 | |||
| Yes | 51 (34.0) | 20 (27.4) | 31 (40.3) | |
| No | 99 (66.0) | 53 (72.6) | 46 (59.7) | |
| Pack yrsc | 0.83 | |||
| Mean (SD) | 81.2 (38.2) | 80.5 (42.0) | 81.8 (34.4) | |
| Range | 10–185 | 10–185 | 10–160 | |
| Enrollment duration (yr) | <0.0001 | |||
| Mean (SD) | 4.1 (3.6) | 2.3 (2.1) | 5.8 (3.8) | |
| Range | 0.10–15.0 | 0.10–8.4 | 0.5–15.0 | |
| FEV1d at enrollment | 0.65 | |||
| Mean (SD) | 1.63 (0.68) | 1.60 (0.70) | 1.65 (0.67) | |
| Range | 0.47–4.07 | 0.53–3.96 | 0.47–4.07 | |
| Clinic visits (no.) | <0.0001 | |||
| Mean (SD) | 43 (40) | 23 (21) | 62 (45) | |
| Range | 3–176 | 3–85 | 6–176 | |
| Exacerbation visits (no.) | <0.0001 | |||
| Mean (SD) | 8 (9) | 4 (4) | 11 (11) | |
| Range | 0–42 | 0–16 | 0–42 | |
| Courier samples (no.) | 0.11 | |||
| Mean (SD) | 10 (15) | 8 (13) | 12 (17) | |
| Range | 0–48 | 0–44 | 0–48 | |
a
One subject with H. influenzae was missing data on race.
b
P values are from chi-square tests for race, sex, and current smoker and from t tests for all other variables. Boldface indicates a significant P value.
c
Pack years were calculated by multiplying the number of packs of cigarettes smoked by the number of years the participant smoked.
d
FEV1, median forced expiratory volume in 1 s.