None of the participants suffered from endocrine conditions with altered cortisol production (Cushing syndrome or Addison's disease) or from neurodegenerative diseases associated with changes in cortisol and BDNF levels like Alzheimer's disease, Parkinson's disease, or Huntington's disease (44, 45). This evidence concerns the gene BDNF and Cushing syndrome due to macronodular adrenal hyperplasia.