Table 1. Baseline Characteristics.
| Variable | Total Enrolled (n = 203) |
Nonrandomized (n=116) |
Placebo (n = 47) |
Varenicline (n = 40) |
|---|---|---|---|---|
| Age, ya | ||||
| Mean (SD) | 47.5 (10.2) | 46.9 (10.0) | 45.7 (10.3) | 51.4 (9.6) |
| Range | 22-68 | 22-68 | 23-66 | 23-65 |
| Women, No. (%) | 80 (39) | 48 (41) | 16 (34) | 16 (40) |
| Race/ethnicity, No. (%) | ||||
| White | 151 (74) | 87 (75) | 34 (72) | 30 (75) |
| Black | 35 (17) | 20 (17) | 6 (13) | 9 (23) |
| Other | 17 (8) | 9 (8) | 7 (15) | 1 (3) |
| Hispanic | 8 (4) | 6 (5) | 0 | 2 (5) |
| Not a high school graduate, No. (%) | 49 (24) | 30 (26) | 10 (22) | 9 (23) |
| Never married, No. (%) | 132 (65) | 80 (69) | 31 (66) | 21 (53) |
| Disabled, No. (%) | 132 (65) | 80 (69) | 29 (62) | 23 (58) |
| Cigarettes smoked per d, average lifetime | ||||
| Mean (SD) | 25.9 (14.2) | 28.0 (16.5) | 22.1 (9.6) | 24.2 (9.4) |
| Range | 4-100 | 4-100 | 7-40 | 10-50 |
| Expired carbon monoxide, ppm | ||||
| Mean (SD) | 23.1 (14.9) | 24.4 (15.5) | 22.6 (13.2) | 20.1 (15.1) |
| Range | 2-88 | 2-88 | 3-60 | 4-69 |
| Age at initiation of regular smoking, y | ||||
| Mean (SD) | 17.6 (5.7) | 18.0 (6.0) | 17.1 (5.1) | 17.4 (5.7) |
| Range | 6-45 | 7-45 | 6-39 | 8-32 |
| FTND score | ||||
| Mean SD | 6.1 (1.8) | 6.3 (1.8) | 5.9 (1.7) | 5.9 (2.0) |
| ≥6, No. (%) | 127 (64) | 76 (67) | 28 (61) | 23 (58) |
| Prior cessation attempts, No. (%) | ||||
| None | 25 (12) | 20 (17) | 3 (6) | 2 (5) |
| ≥5 | 70 (34) | 39 (34) | 16 (34) | 15 (38) |
| Psychiatric symptom ratings | ||||
| SANS composite score | ||||
| Mean (SD) | 35.0 (14.7) | 35.7 (14.8) | 32.7 (15.6) | 36.0 (13.3) |
| Range | 4-73 | 4-73 | 6-69 | 12-72 |
| BPRS total score | ||||
| Mean (SD) | 51.1 (13.1) | 50.0 (13.2) | 50.3 (11.7) | 55.6 (13.8) |
| Range | 29-98 | 29-89 | 33-72 | 30-98 |
| CDSS total score | ||||
| Mean (SD) | 4.1 (3.3) | 3.7 (3.1) | 4.7 (3.4) | 4.6 (3.9) |
| Range | 0-15 | 0-14 | 0-12 | 0-15 |
| Psychiatric diagnosis, No. (%) | ||||
| Schizophrenia spectrum | 185 (91) | 108 (93) | 41 (87) | 36 (90) |
| Bipolar disorder | 18 (9) | 8 (7) | 6 (13) | 4 (10) |
| Prior substance use disorder | 94 (48) | 50 (44) | 22 (48) | 22 (58) |
| Antipsychotic medication, No. (%) | ||||
| Conventional antipsychotics only | 24 (13) | 16 (15) | 4 (10) | 4 (11) |
| Atypical other than clozapine | 119 (65) | 67 (63) | 28 (68) | 24 (67) |
| Clozapine | 41 (22) | 24 (22) | 9 (22) | 8 (22) |
| No. of psychotropic medications | ||||
| Mean (SD) | 1.1 (0.9) | 1.1 (1.0) | 1.2 (1.0) | 1.1 (0.9) |
| Range | 0-4 | 0-3 | 0-4 | 0-3 |
| BMI | ||||
| Mean (SD) | 31.7 (6.7) | 31.5 (6.9) | 31.9 (6.3) | 32.0 (6.7) |
| Range | 19-58 | 20-58 | 20-48 | 19-49 |
Abbreviations: BPRS, Brief Psychiatric Rating Scale, for which higher scores in a range of 24 to 168, indicate more severe symptoms; BMI, body mass index, weight in kilograms divided by the square of the height in meters, for which 30 or higher indicates obesity; CDSS, Calgary Depression Scale for Schizophrenia, for which higher scores in a range of 0 to 27 indicate more severe symptoms; FTND, Fagerstrom Test for Nicotine Dependence, for which scores of 6 or higher in a range of 0 to 10 indicate severe dependence; SANS, Schedule for Assessment of Negative Symptoms, for which higher scores in a range of 0 to 85 indicate more severe symptoms.
There were no significant between-group differences in baseline characteristics in randomized groups except for age. P values based on 2-sample t tests or χ2 tests (P = .01; 2-sample t test) and a trend, P = .06, for BPRS scores to be higher at baseline in those assigned to varenicline.