“…Despite the reported association between HRV and depression, however, there are conflicting observations on HRV in major depression. HRV increased after successful pharmacological and cognitive-behavioral therapy (Apelbaum, 2001; Balogh, Fitzpatrick, Hendricks, & Paige, 1993; Chambers & Allen, 2002; Khaykin et al, 1998; McGrady, 1994; Peniston, Hughes, & Kulkosky, 1986; Ross, Quitkin, & Klein, 2002; Sala et al, 2009), but HRV was found not to differ between healthy controls and physically healthy depressed adults (Sayar, Güleç, Gökçe, & Ak, 2002; Yeragani et al, 1991). A correlation between reduced HRV and severity of disease has been described in major depressive disorder, with the HRV abnormalities not being resolved by pharmacological therapy (Kemp et al, 2010), whereas a study on a large patient population, adjusted for relevant covariates, suggests that antidepressants but not major depression per se reduce HRV, therefore implying a possible side effect of antidepressant medication on HRV (Licht, de Geus, van Dyck, & Penninx, 2010; Licht, Penninx, & de Geus, 2011).…”