In patients with major depressive disorders, depression, stress axis activity and problem solving skills as a proxy of executive functions are unrelated

Abstract

IntroductionMajor depressive disorders (MDD) are among the most prevalent psychiatric disorders worldwide. While there is abundant literature showing that an increased cortisol secretion, understood as a proxy of the deteriorated hypothalamus-pituitary-adrenocortical axis activity (HPA AA), and poor cognitive performance are tightly related, less is known as regards to the HPA AA and higher cognitive information processes such as problem solving.AimsInvestigating the association between cortisol secretion and problem solving performance among patients with MDD.MethodsFifteen inpatients with MDD (HDRS > 24; mean age: 59 years; 80% females) underwent a pharmacologic HPA AA challenge both at baseline and six weeks later to assess the cortisol secretion. They were treated with standard antidepressants at therapeutic dosages. Further, they learned how to solve the Tower-of-Hanoi problem-solving task (ToH-PS-T) and how to apply the problem solving strategy to other tasks (transfer). Testing occurred both at baseline and six weeks later. Outcome variables were symptoms of depression, cortisol secretion and the performance to transfer the acquired ToH-PS-T.ResultsBoth symptoms of depression and cortisol secretion decreased over time, and transfer performance increased over time. Neither at baseline nor six weeks later, symptoms of depression, transfer performance and cortisol secretion were statistically related.ConclusionsThe pattern of results suggests that cortisol secretion as a proxy of physiological stress regulation, symptoms of depression, and higher order cognitive performances seem unrelated. Given that cognitive information processing performance substantively increased regardless from depression and cortisol secretion, problem-solving skills need to be focused separately.Disclosure of interestThe authors have not supplied their declaration of competing interest.