This 2015 worldwide human study was:
“The largest study to date investigating the role of HPA [hypothalamic–pituitary–adrenal] axis related genes in response to a psychological therapy. Furthermore, this is the first study to demonstrate that DNA methylation changes may be associated with response to psychological therapies in a genotype-dependent manner.
In this study, we tested the association between polymorphisms of FKBP5 [a gene that produces a protein that dampens glucocorticoid receptor sensitivity primarily in areas of the limbic system such as the hippocampus and amygdala] and GR [glucocorticoid receptor gene] and response to CBT [cognitive behavior therapy] in children with anxiety disorders (N = 1,152), and examined change in DNA methylation at specific regions of these genes during the course of CBT in a subset of the sample (n = 98).
No significant association was found between GR methylation and response. Allele-specific change in FKBP5 methylation was associated with treatment response.”
Regarding “treatment response:”
“Subjects aged 5–18 (mean: 9.8 years) met DSM-IV criteria for primary diagnosis of an anxiety disorder.
Clinical severity ratings (CSRs) were usually based on composite parent and child reports, and were assigned on a scale of 0–8.  [linked below]
Treatment response was defined as the change in primary anxiety disorder severity from pretreatment to follow-up. A diagnosis was made when the child met diagnostic criteria and received a CSR of 4 or more. Remission was regarded as the absence of the primary anxiety according to diagnostic criteria, as determined by the clinicians at the follow-up interview.”
Scenarios where nine-year-olds and their parents may have benefited from skewing their “composite parent and child reports” either way:
- Parents benefited from an anxious-child report (financial support provided, social services provided, avoided undesirable activities like going to work, continued psychological dependence, provided victim celebrity, enabled their own problems)
- Parents benefited from a well-child report (freed up time to pursue desirable activities, financial relief, relief from court-ordered or social-services-required activities, covered up their own contributions to the child’s problems)
- Nine-year-olds benefited from an anxious report (relief from undesirable activities like school attendance, continued psychological dependence, provided victim celebrity, activities structured around their condition, enabled the parents’ problems)
- Nine-year-olds benefited from a well report (symptom reduction, met parental expectations, freed up time to pursue desirable activities, covered up the parents’ contributions to the child’s problems).
I wonder what “treatment response” criteria were available other than self-serving reports and “diagnostic criteria, as determined by the clinicians.” Every day medical personnel hear patients self-report conditions where biological measurements may confirm or indicate something different. Did the “diagnostic criteria, as determined by the clinicians” include comparisons to relevant biological measurements?
The related study linked below points out:
“Although CBT has been established as an efficacious treatment, roughly 40% of children retain their disorder after treatment.”
Its focus was also on predictors (other than genetic) of CBT outcomes.
Neither study provided evidence of attempts to find originating causes for the children’s conditions. Were the international CBT approaches only interested in treating symptoms?
http://onlinelibrary.wiley.com/doi/10.1002/da.22430/full “HPA AXIS RELATED GENES AND RESPONSE TO PSYCHOLOGICAL THERAPIES: GENETICS AND EPIGENETICS”
Related 2015 study: http://www.jaacap.com/article/S0890-8567%2815%2900191-4/pdf “Clinical Predictors of Response to Cognitive-Behavioral Therapy in Pediatric Anxiety Disorders: The Genes for Treatment (GxT) Study”