Table 2.
Neurodevelopmental Factors by Group
| SzO | BpO | CcO | F | P | SzO Vs CcO | BpO Vs CcO | BpO Vs SzO | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Least Square Means (SE) | OR/Beta [95% CI] | t | P | OR/Beta [95% CI] | t | P | OR/Beta [95% CI] | t | P | |||||
| Paternal age at birth | 35.6 (0.74) | 35.1 (0.54) | 34.0 (0.55) | 1.8 | .17 | |||||||||
| Maternal age at birth | 31.1 (0.62) | 30.7 (0.46) | 31.8 (0.46) | 1.6 | .21 | |||||||||
| Obstetric complicationsa | 65.9% (6.9) | 56.8% (5.3) | 38.1% (5.3) | 5.6 | .004 | OR = 3.1 [1.5 to 6.6] | 3.0 | .003 | OR = 2.2 [1.2 to 4.2] | 2.6 | .010 | OR = 1.4 [0.70 to 2.9] | 0.88 | .38 |
| Birth weight | 3.23 (0.12) | 3.17 (0.10) | 3.29 (0.11) | 0.76 | .47 | |||||||||
| Childhood developmental difficulties* | 44.6% (7.7) | 23.5% (4.7) | 18.6% (4.4) | 4.9 | .008 | OR = 3.5 [1.5 to 8.0] | 3.0 | .003 | OR = 1.3 [0.6 to 2.8] | 0.78 | .44 | OR = 2.6 [1.2 to 5.7] | 2.4 | .017 |
| Neurological soft signs | 14.7 (3.3) | 13.2 (3.3) | 8.8 (3.5) | 12.4 | <.001 | Beta = 5.8 [3.4 to 8.3] | 4.7 | <.001 | Beta = 4.3 [2.0 to 6.6] | 3.7 | <.001 | Beta = 1.7 [−1.1 to 4.44] | 1.2 | .23 |
| General intelligenceb | 92.3 (2.0) | 104.8 (1.5) | 106.9 (1.5) | 22.6 | <.001 | Beta = −14.7 [−19.1 to −10.2] | −6.5 | <.001 | Beta = −2.1 [−5.8 to 1.6] | −1.1 | .27 | Beta = −12.6 [8.1 to 17.0] | −5.6 | .<001 |
| Grey matter volume | ||||||||||||||
| Total | 759.1 (6.4) | 762.9 (6.2) | 765.8 (6.4) | 4.4 | .014 | Beta = −6.7 [−11.3 to −2.2] | −2.95 | .003 | Beta = −2.9 [−6.9 to 1.0] | −1.5 | .14 | Beta = −3.8 [−8.3 to 0.67] | −1.7 | .095 |
| Frontal lobe | 143.0 (4.4) | 143.3 (4.4) | 144.3 (4.4) | 0.91 | .40 | |||||||||
| Temporal lobe | 123.5 (2.2) | 123.2 (2.1) | 123.8 (2.2) | 0.30 | .74 | |||||||||
| Parietal lobe | 91.9 (1.1) | 92.8 (1.0) | 93.5 (1.0) | 1.5 | .23 | |||||||||
| Hippocampus/ parahippocampal gyrus | 13.4 (0.22) | 13.5 (0.20) | 13.5 (0.22) | 0.24 | .78 | |||||||||
Note: SzO, offspring of probands with schizophrenia; BpO, offspring of probands with bipolar disorder; CcO, offspring of community controls; OR, odds ratio; CI, confidence interval. Generalized linear mixed model analyses including family and site as random variables adjusted by age, gender, and total intracranial volume (for grey matter volume) where significant. 1Includes difficulties reported in acquisition of language, motor, reading/writing skills, and elimination disorders. Socioeconomic status had an effect on obstetric complications and general intelligence. When controlling for socioeconomic status in group analyses:
a F = 4.6, P = .011. SzO vs CcO: OR = 2.8 [1.2 to 6.5], t = 2.4, P = .016. BpO vs CcO: OR = 2.25 [1.2 to 4.2], t = 2.6, P = .010. SzO vs BpO: ns.
b F = 6.8, P = .001. SzO vs CcO: Beta = −8.7 [−13.5 to −4.1], t = 3.7, P < .001 BpO vs CcO: Beta = −2.0 [−5.5 to 1.5], t = −1.1, P = .27 SzO vs BpO: Beta = −6.8 [−11.5 to −2.1], t = −2.9, P = .005.