Atomoxetine, Diurnal Profiles of Cortisol and α-amylase, Possible Biological Markers of Treatment Success

Scientific and clinical Background

There is very good evidence that the hypothalamic-pituitary- adrenal (HPA) axis is disturbed in depression. There is some evidence that the stress system also plays a role in attention deficit disorder (ADHD ) (O'Connor, Heron et al. 2002).

The investigators have shown that motor activity and attention deficit/concentration are core symptoms of depression (Kammerer, Marks et al. 2009; Kammerer 2010). These symptoms are also the core symptoms of attention deficit hyperkinetic disorder (ADHD). There is increasing evidence that the diurnal variation of markers of the stress system (e.g. salivary cortisol for the hypothalamic pituitary adrenal (HPA) axis, salivary amylase for the sympathetic adrenomedullar (SAM) axis) reveal characteristics of different types of depression, e.g. atypical depression (Tops, Riese et al. 2008), post partum depression (Tops, Riese et al. 2008; Taylor, Glover et al. 2009) and related states, e.g. posttraumatic stress disorder (PTSD) (Wessa, Rohleder et al. 2006) and chronic fatigue syndrome (Roberts, Wessely et al. 2004).

There is some evidence that the saliva cortisol levels and the cortisol awakening rise may be markers of treatment success (Roberts, Papadopoulos et al. 2009). Salivary cortisol and salivary amylase are easy to study as only saliva is needed. (Clow, Hucklebridge et al.; Kirschbaum and Hellhammer 1989; O'Donnell, Kammerer et al. 2009). The investigators have tested saliva amylase, found it to be robust and a useful marker for the function of the SAM system (O'Donnell, Kammerer et al. 2009).

However there is still insufficient research into the diurnal profile of cortisol and amylase with children suffering from ADHD. This causes a serious lack of information for both clinical child and adolescent psychiatry and paediatrics as well as for the research community.