Table 1.
Relationship of Tourette syndrome or chronic tic disorders to novel potential risk factorsa
| Tourette syndrome only |
Tourette syndrome/chronic tic disorder |
|||||||
|---|---|---|---|---|---|---|---|---|
| Unadjusted |
Adjusted for SES |
Unadjusted |
Adjusted for SES |
|||||
| Exposure | OR (95% CI) | P | OR (95% CI) | P | OR (95% CI) | P | OR (95% CI) | P |
| Maternal fitness | ||||||||
| Pre-pregnancy weight, kg | 1.01 (0.98-1.04) | 0.43 | 1.01 (0.99-1.02) | 0.41 | ||||
| Existing diabetes | 0.37 (0.05-2.78) | 0.34 | 0.46 (0.11-1.91) | 0.29 | ||||
| Maternal smoking before pregnancy | 1.28 (0.68-2.38) | 0.45 | 1.33 (0.69-2.57) | 0.40 | 1.43 (0.97-2.13) | 0.07 | 1.30 (0.85-1.99) | 0.22 |
| Cannabis use before pregnancy | 2.43 (0.86-6.84) | 0.09 | 2.38 (0.83-6.81) | 0.11 | 1.46 (0.64-3.73) | 0.37 | 1.32 (0.56-3.08) | 0.52 |
| Parity (second or later born v. first born) | 0.60 (0.33-1.11) | 0.10 | 0.62 (0.42-0.92) | 0.02 | ||||
| Early pregnancy exposures, prior miscarriage/stillborn | 1.02 (0.51-2.05) | 0.96 | 1.16 (0.75-1.79) | 0.50 | ||||
| Toxic exposures Influenza | ||||||||
| 1st trimester | 1.01 (0.36-2.82) | 0.99 | 0.86 (0.41-1.77) | 0.68 | ||||
| 2nd trimester | 0.81 (0.19-3.35) | 0.77 | 1.38 (0.67-2.86) | 0.39 | ||||
| 3rd trimester | 1.49 (0.46-4.84) | 0.50 | 1.23 (0.54-2.84) | 0.62 | ||||
| Anytime in pregnancy | 1.12 (0.52-2.39) | 0.78 | 1.23 (0.76-1.97) | 0.40 | ||||
| Cannabis use in 1st trimester | 4.74 (1.67-13.44) | 0.003 | 4.68 (1.61-13.63) | 0.005 | 1.87 (0.68-5.17) | 0.23 | 1.68 (0.60-4.71) | 0.32 |
| Cannabis use in last 2 months of pregnancy | 6.37 (2.23-18.21) | 0.001 | 6.00 (2.06-17.50) | 0.001 | 3.11 (1.23-7.84) | 0.016 | 2.82 (1.10-7.22) | 0.03 |
| Any illegal drug use in pregnancy | 4.28 (1.51-12.11) | 0.006 | 4.20 (1.45-12.16) | 0.01 | 2.10 (0.84-5.25) | 0.11 | 1.93 (0.76-4.87) | 0.17 |
| Partner smoked at start of pregnancy | 1.50 (0.77-2.95) | 0.24 | 1.24 (0.80-1.93) | 0.33 | ||||
| Pregnancy complications | ||||||||
| Diabetes in pregnancy | 1.66 (0.51-5.38) | 0.40 | 1.14 (0.46-2.81) | 0.78 | ||||
| Hypertensive disorder of pregnancy | 0.98 (0.46-2.10) | 0.96 | 1.01 (0.62-1.68) | 0.95 | ||||
| Placental weight (adjusted by birth weight), g | 1.00 (1.00-1.00) | 0.57 | 1.00 (0.99-1.00) | 0.96 | ||||
| Twin v. singleton | 0.99 (0.14-7.26) | 0.99 | 1.23 (0.39-3.92) | 0.73 | ||||
| Predicted weight gainb | ||||||||
| Less than adequate | 5.69 (1.99-16.25) | 0.001 | 9.70 (2.71-34.73) | <0.0001 | 2.37 (1.22-4.60) | 0.01 | 3.18 (1.52-6.65) | 0.002 |
| More than adequate | 1.98 (0.74-5.30) | 0.17 | 2.95 (0.88-10.05) | 0.09 | 1.27 (0.73-2.20) | 0.40 | 1.54 (0.82-2.89) | 0.18 |
| Complications of delivery | ||||||||
| Inspired oxygen | NA | NA | 0.66 (0.09-4.82) | 0.69 | ||||
| Mechanical ventilation | NA | NA | 1.35 (0.18-9.98) | 0.77 | ||||
| Resuscitation | 0.28 (0.04-2.01) | 0.21 | 1.15 (0.58-2.30) | 0.69 | ||||
| Preterm labour/PROM | NA | NA | 1.64 (0.22-12.09) | 0.63 | ||||
NA, no cases had the exposure; OR, odds ratio; PROM, premature rupture of membranes; SES, socioeconomic status.
a.
Only variables where unadjusted P-value <0.10 were carried forward and adjusted. See online Table DS3 for numbers, means and percentage of cases and controls for each exposure.
b.
Predicted using spline models and adjusted for gestational age.34 Parity is defined as second born or later compared with first born as the reference category.