FIGURE 1
Pairwise comparisons of early risk factors during pregnancy and the child’s first years of life in children with familial high risk for schizophrenia, children at familial high risk for bipolar disorder and children of parents without these disorders
| Early risk factor | FHR-SZ | FHR-BP | PBC | P-value | P-value | |||
|---|---|---|---|---|---|---|---|---|
| Pairwise comparisons | ||||||||
| FHR-SZ vs. PBC | FHR-BP vs. PBC | FHR-SZ vs. FHR-BP | ||||||
| N (%) | N (%) | N (%) | - | - | - | - | ||
| Risk factors during pregnancy | ||||||||
| Unwanted pregnancy | ||||||||
| - | Yes | 21 (10.77) | 7 (5.93) | 2 (1.02) | <0.001a | <0.001a | 0.011a | 0.146 a |
| - | No | 174 (89.23) | 111 (94.07) | 195 (98.98) | ||||
| Unplanned pregnancy | ||||||||
| - | Yes | 81 (41.12) | 27 (22.88) | 28 (14.14) | <0.001a | <0.001a | 0.047a | 0.001a |
| - | No | 116 (58.88) | 91 (77.12) | 170 (85.86) | ||||
| Medication intake by biological mother during pregnancy | ||||||||
| - | Yes | 51 (26.02) | 24 (20.51) | 19 (9.64) | <0.001a | <0.001a | 0.007a | 0.269a |
| - | No | 145 (73.98) | 93 (79.49) | 178 (90.36) | ||||
| Cigarette smoking by biological mother during pregnancy | ||||||||
| - | Yes | 79 (40.93) | 27 (23.48) | 21 (10.71) | <0.001a | <0.001a | 0.003a | 0.002a |
| - | No | 114 (59.07) | 88 (76.52) | 175 (89.29) | ||||
| Alcohol consumption by biological mother during pregnancy | ||||||||
| - | Yes, once weekly | 9(4.66) | 4 (3.39) | 4 (2.05) | 0.377b | - | - | - |
| - | Yes, sometimes | 46 (23.83) | 37 (31.36) | 57 (29.23) | ||||
| - | No | 138 (71.50) | 77 (65.25) | 134 (68.72) | ||||
| Drug use by biological mother during pregnancy | ||||||||
| - | Yes | 8 (3.98) | 1 (0.85) | 0 (0.00) | 0.004b | 0.007b | 0.372b | 0.162b |
| - | No | 193 (96.02) | 117 (99.15) | 199 (100.00) | ||||
| Stressful life events for biological mother during pregnancye | ||||||||
| - | None | 55 (31.25) | 34 (31.19) | 87 (47.54) | <0.001a | <0.001a | <0.001a | 0.968a |
| - | One | 56 (31.82) | 37 (33.94) | 66 (36.07) | ||||
| - | Two | 34 (19.32) | 21 (19.27) | 23(12.57) | ||||
| - | Three | 31(17.61) | 17 (15.60) | 7 (3.83) | ||||
| Risk markers during the child’s first years of life | ||||||||
| Spent the most time with the child during the first years of life (0–3 years old) | ||||||||
| - | Biological parent | 190 (95.96) | 117 (100.00) | 195 (100.00) | 0.001b | 0.007b | NA | 0.028b |
| - | Other | 8 (4.04) | 0 (0.00) | 0 (0.00) | ||||
| Stressful life events for primary caregiver during the child’s first years of life (0–3 years old)e | ||||||||
| - | None | 34 (16.83) | 22 (18.33) | 87 (43.50) | <0.001a | <0.001a | <0.001a | 0.438a |
| - | One | 52 (25.74) | 22 (18.33) | 58 (29.00) | ||||
| - | Two | 54 (26.73) | 32 (26.67) | 38 (19.00) | ||||
| - | Three | 62 (30.69) | 44 (36.67) | 17 (8.50) | ||||
| Stressful life events for the child during the child’s first years of life (0–3 years old)e | ||||||||
| - | None | 57 (28.22) | 43 (35.83) | 117 (58.50) | <0.001a | <0.001a | <0.001a | 0.159a |
| - | One | 60 (29.70) | 28 (23.33) | 58 (29.00) | ||||
| - | Two | 45 (22.28) | 33 (27.50) | 16 (8.00) | ||||
| - | Three | 40 (19.80) | 16 (13.33) | 9 (4.50) | ||||
| Comforting (0–12 months old)f | ||||||||
| - | Median (IQI) | 2 (1;3)c | 2 (1;2)c | 1 (1;2)c | 0.180d | - | - | - |
| Eating (0–12 months old)f | ||||||||
| - | Median (IQI) | 1 (1;3)c | 1 (1;2)c | 1 (1;2)2 | 0.139d | - | - | - |
| Sleeping (0–12 months old)f | ||||||||
| - | Median (IQI) | 2 (1;3)c | 2 (1;3)c | 1 (1;3)c | 0.388d | - | - | - |
| Hypersensitivity (0–48 months old) | ||||||||
| - | Yes | 41 (20.60) | 25 (21.19) | 29 (14.65) | 0.212a | - | - | - |
| - | No | 158 (79.40) | 93(78.81) | 169 (85.35) | ||||
| Hyposensitivity (0–48 months old) | ||||||||
| - | Yes | 12 (6.06) | 2 (1.69) | 4 (2.02) | 0.062b | - | - | - |
| - | No | 186 (93.94) | 116 (98.31) | 194 (97.98) | ||||
| Stimulation seeking (0–48 months old) | ||||||||
| - | Yes | 45 (22.73) | 20 (17.09) | 24 (12.18) | 0.022a | 0.006a | 0.225a | 0.233a |
| - | No | 153 (77.27) | 97 (82.91) | 173 (87.82) | ||||
| Attachment behavior (9–24 months old) | ||||||||
| - | Yes | 49 (25.00) | 19 (16.38) | 32 (16.24) | 0.055a | - | - | - |
| - | No | 147 (75.00) | 97 (83.62) | 165 (83.76) | ||||
| Mean cumulative risk | ||||||||
| - | Number of risk factors | 4.78 (2.34)g | 4.03 (2.15)g | 2.83 (1.74)g | <0.001h | <0.001h | <0.001h | 0.006h |
Definitions and ratings of risk factors from the anamnestic interview with the primary caregiver
| Variable | Definition | Rating |
|---|---|---|
| Risk factors during pregnancy | ||
| Unwanted pregnancy | The pregnancy was not wanted | Yes |
| No | ||
| Unplanned pregnancy | The pregnancy was not planned | Yes |
| No | ||
| Medication intake by biological mother during pregnancy | Biological mother took regular medicine during the pregnancy | Yes |
| No | ||
| Cigarette smoking by biological mother during pregnancy | Biological mother smoked cigarettes during pregnancy | Yes |
| No | ||
| Alcohol consumption by biological mother during pregnancy | Biological mother drank alcohol during pregnancy | Yes, once weekly |
| Yes, sometimes | ||
| No | ||
| Drug use by biological mother during pregnancy | Biological mother took drugs during pregnancy | Yes |
| No | ||
| Stressful life events for biological mother during pregnancy | Stressful life events for biological mother during pregnancy (for instance critical illness or death in the family, financial problems, unstable housing conditions)* | 0–3 stressful life events |
| Risk factors during the child’s first years of life | ||
| Spent the most time with the child during the first years of life (0–3 years old) | Person that the child spent the most time with during the first three years of life | Biological parent |
| Other | ||
| Stressful life events for primary caregiver during the child’s first years of life (0–3 years old) | Stressful life events for the primary caregiver during the child’s first years of life (0–3 years) (for instance psychosocially, death in the family, disease)* | 0–3 stressful life events |
| Stressful life events for the child during the child’s first years of life (0–3 years old) | Stressful life events for the child during the child’s first years of life (0–3 years) (for instance psychosocially, death in the family, disease)* | 0–3 stressful life events |
| Comforting (0–12 months old) | Scale from 1 to 7, with 1 indicating that the child was happy, easy to comfort and pleased most of the time, and 7 indicating that the child was difficult to comfort and displeased most of the time | 1–7 |
| Eating (0–12 months old) | Scale from 1 to 7, with 1 indicating no problems with eating, and 7 indicating a lot of trouble with eating and keeping weight | 1–7 |
| Sleeping (0–12 months old) | Scale from 1 to 7, with 1 indicating no problems with sleeping, and being rested and happy after sleep, and 7 indicating sleeping unrestful and interruptedly most of the time, often being tired and not well rested | 1–7 |
| Hypersensitivity (0–48 months old) | The child responds very strongly to stimuli, is particularly sensitive and overreact to what he/she experiences, and displays avoidant behaviour. The child easily becomes anxious, starts to cry or freezes at certain stimuli. The child responds with discomfort to e.g. touching, loud noises, strong light or an unknown smell or taste | Yes |
| No | ||
| Hyposensitivity (0–48 months old) | The child doesn’t respond to stimuli (i.e. what is happening around them), even though he/she doesn’t seem sad or anxious. The child clearly doesn’t respond as much as other children to e.g. noises, smell, taste, touch | Yes |
| No | ||
| Stimulation seeking (0–48 months old) | The child displays stimulus-seeking behaviour to a degree where he/she accidentally destroys things or does something, that is potentially self-harming | Yes |
| No | ||
| Attachment behaviour (9–24 months old) | The child displays poor attachment behaviour meaning that the child doesn’t seek a parent or another familiar adult if he/she gets upset, scared or frightened | Yes |
| No | ||
Demographic and clinical characteristics of children, index parents and non-index parents from families with parental schizophrenia, parental bipolar disorder and families without schizophrenia or bipolar disorder
| FHR-SZ | FHR-BP | PBC | P-value | P-value | |||
|---|---|---|---|---|---|---|---|
| Pairwise comparisons | |||||||
| FHR-SZ vs. PBC | FHR-BP vs. PBC | FHR-BP vs. FHR-SZ | |||||
| Children, N | 202 | 120 | 200 | - | - | - | - |
| Female, N (%) | 93 (46.04) | 56 (46.67) | 93 (46.50) | 0.993b | - | - | - |
| Age at inclusion, mean (SD) | 7.84 (0.22) | 7.86 (0.20) | 7.81 (0.20) | 0.097c | - | - | - |
| CGASa, N, mean (SD) | 199, 68.07 (15.40) | 118, 73.55 (14.91) | 197, 77.71 (13.47) | <0.001c | <0.001c | 0.015c | 0.001c |
| Index parents, N | 200 | 116 | 204 | - | - | - | - |
| Female, N (%) | 111 (55.50) | 64 (55.17) | 115 (56.37) | 0.974b | - | - | - |
| Age at child’s birth, mean (SD) | 30.20 (6.14) | 33.12 (7.03) | 32.83 (4.78) | <0.001c | <0.001c | 0.670c | <0.001c |
| Employed or studying, N (%) | 93 (49.73) | 61 (55.96) | 185 (92.04) | <0.001b | <0.001b | <0.001b | 0.301b |
| Education, N | 178 | 109 | 197 | ||||
| Primary/lower secondary, N (%) | 54 (30.34) | 10 (9.17) | 8 (4.06) | ||||
| Upper secondary, vocational short cycle tertiary, N (%) | 76 (42.70) | 45 (41.28) | 95 (48.22) | <0.001b | <0.001b | 0.142b | <0.001b |
| Bachelor degree, equivalent or higher, N (%) | 48 (26.97) | 54 (49.54) | 94 (47.72) | ||||
| Non-index parents, N | 186 | 114 | 192 | - | - | - | - |
| Female, N (%) | 82 (44.09) | 51 (44.74) | 83 (43.23) | 0.966b | - | - | - |
| Age at child’s birth, mean (SD) | 30.92 (6.37) | 33.10 (5.39) | 32.97 (4.28) | <0.001c | <0.001c | 0.814c | 0.001c |
| Employed or studying, N (%) | 133 (75.14) | 93 (85.32) | 179 (95.21) | <0.001b | <0.001b | 0.003b | 0.040b |
| Education, N | 176 | 106 | 187 | ||||
| Primary/lower secondary, N (%) | 31 (17.61) | 5 (4.72) | 10 (5.35) | ||||
| Upper secondary, vocational short cycle tertiary, N (%) | 86 (48.86) | 44 (41.51) | 89 (47.59) | <0.001b | <0.001b | 0.543b | <0.001b |
| Bachelor degree, equivalent or higher, N (%) | 59 (33.52) | 57 (53.77) | 88 (47.06) | ||||