“…More detailed investigations of HPA axis function in individuals with depression across time have led to conflicting results, with some studies finding a return to normal functioning of the HPA axis after successful antidepressant treatment (Anacker, Zunszain, Carvalho, & Pariante, 2011; Pariante, 2009; Ruhe et al, 2015; Schule, 2007) or during periods of euthymia (Lange et al, 2013) and others reporting abnormalities of HPA axis function even during periods of remission from depression, including both hyper-reactivity (Hohne et al, 2014; Holsen et al, 2013; Keating, Dawood, Barton, Lambert, & Tilbrook, 2013; Lok et al, 2012) and hypo-reactivity (Ahrens et al, 2008; Bagley, Weaver, & Buchanan, 2011) of the HPA axis. Studies evaluating HPA axis reactivity in individuals with histories of early life stress have more consistently demonstrated persistent hyperreactivity of the HPA axis over time irrespective of current psychopathology/symptoms (Heim, Newport, Mletzko, Miller, & Nemeroff, 2008), leading to the hypothesis that the finding of HPA axis hyperreactivity in individuals with depression represents an underlying biological predisposition to depression shaped by early life events rather than a transient biomarker of depressive symptoms (Pariante & Lightman, 2008).…”