Genetic Makeup Affects Anxious Children's Response to CBT

Determining whether psychotherapy or a drug intervention would work better for a child with anxiety disorder is challenging. To investigate this question, researchers genotyped the short and long allele polymorphisms of 5-HTTLPR, the promoter region of the serotonin transporter, in 359 white children with any anxiety diagnosis from Australia and the U.K. (mean age, 9 years; 49% female; 73% of invited patients). Children were participating in various trials of manual-based cognitive-behavioral therapy (CBT; 4–12 weeks; administered in-person or by telephone and typically in group format in Australia). Parents' anxiety and depressive symptoms were assessed at baseline only.

Patients' 5-HTTLPR genotypes were comparable to those in a similar white population without psychiatric disorders. The most common primary anxiety disorders were generalized anxiety disorder (45%), social phobia (21%), and separation anxiety (18%). At follow-up (range, 3–12 months), but not immediately posttreatment, the subgroup that was homozygous for the short allele had a significantly higher percentage of responders to CBT for both the primary anxiety disorder and any anxiety symptoms.