Table 1.
Presentation of environmental risk groups in discovery and replication samples: sociodemographic and disease-related measures
| No risk factors | 1 risk factor | 2 risk factors | ≥3 risk factors | p value (H/χ2) | |
|---|---|---|---|---|---|
| Discovery samplea (N = 121–134) | |||||
| Male schizophrenic subjects | n = 30–33 | n = 32–36 | n = 24–26 | n = 35–39 | |
| Age (years)b | 33.09 (10.24) | 35.68 (11.23) | 31.47 (8.27) | 32.46 (8.66) | p = 0.630 (H = 1.73) |
| Premorbid intelligence MWT-Bc | 103.23 (16.57) | 101.09 (11.80) | 104.48 (14.36) | 97.42 (14.91) | p = 0.172 (H = 5.00) |
| Cognitive composite scored | −0.05 (1.13) | −0.49 (1.07) | 0.22 (0.72) | 0.03 (1.00) | p = 0.651 (H = 1.64) |
| Chlorpromazine equivalents | 751.09 (696.52) | 771.87 (1227.51) | 674.28 (508.49) | 648.83 (569.38) | p = 0.769 (H = 1.13) |
| Suicidalitye | 11 (33.3%) | 8 (23.5%) | 9 (34.6%) | 14 (36.8%) | p = 0.651 (χ2 = 1.64) |
| Replication sample I(N = 392–411) | |||||
| GRAS I male schizophrenic subjects | n = 91–98 | n = 156–166 | n = 91–92 | n = 53–59 | |
| Age (years)b | 46.94 (12.26) | 39.65 (12.50) | 34.51 (10.18) | 32.85 (8.38) | p = 1.6 x 10−5 (H = 24.87) |
| Premorbid intelligence MWT-Bc | 105.35 (17.09) | 103.32 (15.87) | 101.00 (14.26) | 99.23 (15.10) | p = 0.085 (H = 6.61) |
| Cognitive composite scored | 0.15 (1.12) | 0.75 (1.01) | 0.10 (0.93) | −0.01 (0.89) | p = 0.873 (H = 0.70) |
| Chlorpromazine equivalents | 611.92 (571.29) | 703.38 (585.70) | 686.03 (608.01) | 836.07 (622.14) | p = 0.059 (H = 7.43) |
| Suicidalitye | 23 (24.2%) | 57 (34.5%) | 33 (36.6%) | 33 (55.9%) | p = 0.001 (χ2 = 16.11) |
| Replication sample II (N = 238–290) | |||||
| GRAS II male schizophrenic subjects | n = 36–46 | n = 68–84 | n = 67–82 | n = 67–78 | |
| Age (years)b | 45.57 (15.02) | 42.17 (13.83) | 38.50 (14.08) | 35.75 (10.52) | p = 0.011 (H = 11.20) |
| Premorbid intelligence MWT-Bc | 98.09 (14.46) | 102.29 (16.03) | 100.48 (13.36) | 96.39 (9.29) | p = 0.184 (H = 4.84) |
| Cognitive composite scored | −0.23 (1.24) | −0.08 (1.03) | −0.01 (0.84) | −0.08 (0.96) | p = 0.816 (H = 0.94) |
| Chlorpromazine equivalents | 629.15 (513.31) | 747.35 (629.02) | 689.31 (717.18) | 713.84 (532.66) | p = 0.629 (H = 1.74) |
| Suicidalitye | 8 (20.5%) | 12 (14.6%) | 25 (31.6%) | 25 (34.2%) | p = 0.018 (χ2 = 10.08) |
| Replication sample III (N = 345–386) | |||||
| GRAS I-II female schizophrenic subjects | n = 125–140 | n = 118–130 | n = 65–71 | n = 37–43 | |
| Age (years)b | 43.44 (11.75) | 46.67 (12.90) | 40.84 (12.71) | 36.53 (11.31) | p = 0.003 (H = 13.83) |
| Premorbid intelligence MWT-Bc | 103.53 (14.19) | 104.04 (14.28) | 102.96 (15.84) | 99.10 (15.41) | p = 0.147 (H = 5.37) |
| Cognitive composite scored | 0.03 (0.96) | 0.09 (0.99) | 0.24 (0.99) | −0.21 (1.00) | p = 0.164 (H = 5.11) |
| Chlorpromazine equivalents | 536.52 (579.61) | 564.04 (506.21) | 620.48 (628.30) | 650.87 (477.23) | p = 0.167 (H = 5.07) |
| Suicidalitye | 45 (33.6%) | 59 (46.5%) | 33 (46.5%) | 22 (53.7%) | p = 0.052 (χ2 = 7.72) |
| Replication sample IV (N = 299) | |||||
| General population | n = 39 | n = 83 | n = 133 | n = 44 | |
| Age (years) | 26.44 (4.81) | 25.93 (2.46) | 25.56 (3.50) | 25.25 (3.64) | p = 0.117 (H = 5.89) |
| Gender, female/male (% male) | 29/10 (25.6%) | 51/32 (38.6%) | 78/55 (41.4%) | 18/26 (59.1%) | |
| Replication sample V (N = 177–183) | |||||
| General population | n = 13 | n = 54–56 | n = 86–89 | n = 24–25 | |
| Age (years) | 20.54 (0.88) | 20.63 (0.98) | 20.85 (1.12) | 20.88 (1.15) | p = 0.696 (H = 1.44) |
| Gender, female/male (% male) | 7/6 (46.2%) | 41/15 (26.8%) | 56/33 (37.1%) | 20/5 (20.0%) | |
Data are uncorrected means (SD) or n (%); for statistical analysis, Kruskal-Wallis-H, χ2, or Fisher’s exact test was used, all p values two-sided; Bonferroni-corrected p values <0.01 are considered significant and underlined; because of missing data, sample sizes vary;
anote regarding discovery sample: extreme groups of our previous study [18] differ slightly due to elimination of birth complications and neurotrauma, but inclusion of alcohol in the present study;
bcorrected for age at disease onset;
c MWT-B=Mehrfachwahl-Wortschatz-Intelligenztest-B;
dcognitive composite score consists of reasoning (Leistungsprüfsystem-subtest-3), executive function (Trail-Making Test B), verbal learning & memory test (VLMT) [18]; corrected for age, PANSS negative score, and chlorpromazine equivalents (standardized residuals after linear regression);
esuicidality=individuals with past suicide attempts