Table 1.
Demographic Variables of Current Smokers and Nonsmokers among Patients with Schizophrenia and Healthy Controls
| HCs (n=131) | Patients with SZ (n=304) | |||||
|---|---|---|---|---|---|---|
| Smoker | Nonsmoker | Smoker | Nonsmoker | |||
| Variables | n=21 | n=110 | P values (z) | n=76 | n=228 | P values (z) |
| Age (y) | 40.9±12.3 | 34.2±10.9 | 4.39×10–3(2.9) | 51.2±13.0 | 50.4±15.7 | .71 ( .4) |
| Gender (male/female) | 19/2 | 65/45 | 6.00×10–3(7.6)a | 61/15 | 83/145 | 3.32×10–11(44.0)a |
| Education (y) | 16.4±2.0 | 16.7±2.5 | .18 (-1.4) | 11.8±2.1 | 12.0±2.2 | .32 (-1.0) |
| CPD | 14.5±6.5 | – | – | 21.1±13.9 | – | – |
| Heavy smoker (≥30 cigarettes/d) | 0/21 | – | – | 15/61 | – | – |
| Total periods of smoking (y) | 21.8±13.5 | 0.3±1.7 | 1.24×10–25(10.5) | 30.0±13.5 | 0.2±2.0 | 9.44×10–64(16.9) |
| Ever/never smoker | 21/0 | 4/106 | 1.21×10–20(106.0)b | 76/0 | 3/225 | 1.00×10–64(288.6)a |
| CPZ-eq atypical (mg/d) | – | – | – | 342.5±412.2 | 305.0±354.1 | .88 (.1) |
| CPZ-eq typical (mg/d) | – | – | – | 552.6±746.5 | 409.6±663.4 | .021 (2.3) |
| Age at onset (y) | – | – | – | 23.1±7.9 | 24.9±10.7 | .65 (-0.5) |
| Duration of illness (y) | – | – | – | 28.1±15.1 | 25.5±17.2 | .19 (1.3) |
| PANSS positive symptoms | – | – | – | 15.7±5.7 | 15.0±5.5 | .15 (1.4) |
| PANSS negative symptoms | – | – | – | 19.6±6.0 | 19.4±6.6 | .76 (.3) |
| DIEPSS total | – | – | – | 0.6±0.8 | 0.7±0.9 | .66 (-0.4) |
Abbreviations: CPD, cigarettes smoked per day; CPZ-eq., chlorpromazine equivalents of total antipsychotics; DIEPSS, Drug-Induced Extra-Pyramidal Symptons Scale; HC, healthy control; PANSS, Positive and Negative Syndrome Scale; SZ, schizophrenia.
Means±SD are shown. P values<0.05 are shown in boldface and underlined.
a χ 2 test.
bFisher’s exact test.