Parental Psychopathology and Tourette Syndrome/Chronic Tic Disorder in Offspring: A Nationwide Case-Control Study

Objective To determine the associations between maternal and paternal psychiatric diagnoses and Tourette syndrome (TS)/chronic tic disorder (CT) in a nationwide study. Method This nested case-control study linked data derived from three national registers. All singletons born and diagnosed with TS/CT in Finland between January 1991 and December 2010 were identified (n = 1,120) and matched to four controls (n = 4,299). Conditional logistic regression was used to examine the associations between parental psychopathology and TS/CT. Results Altogether, 24.9% of patients with TS/CT and 12.0% of controls had a mother with a psychiatric diagnosis. Similarly, 17.9% and 12.9% had a father with a psychiatric diagnosis. Any maternal and any paternal psychiatric diagnosis was associated with offspring TS/CT (odds ratio [OR] 2.3; 95% CI 1.9−2.7 and OR 1.2; 95% CI 1.01−1.5, respectively). The association between maternal psychiatric diagnosis and TS/CT was stronger than that between paternal psychiatric diagnosis and TS/CT ( p Conclusion Parental psychiatric diagnoses (especially in the mother) are associated with diagnosed offspring TS/CT. Further studies are required before the results can be generalized to all children with TS/CT. The associations between maternal psychiatric disorders and TS may reflect both maternal specific environmental and/or genetic influences.