Table 3.

Overview of studies comparing biological dysregulations across melancholic and atypical depression

Reference	Nr of melancholic depression	Nr of atypical depression	Nr of controls	Summary of findings
Metabolic dysregulation
Lamers et al. 2010 [115]	379	201	-	AD more MetS than MD
Seppala et al. 2012 [53]	293	1391	2,388	AD more MetS than C, no association with MD
Immuno-inflammatory dysregulation
Anisman et al. 1999 [123]	17	31	27	No difference in IL-1b + IL-2
Kaestner et al. 2005 [124]	21	161	37	AD higher IL-1b + IL-1RA than C + MD
Huang et al. 2007 [125]	25	171	40	MD higher IL-1b than AD no difference in IL-10 and TNF-α
Yoon et al. 2012 [126]	70	35	-	AD higher IL-2 and lower IL-4 than MD no differences in IL-6 + TNF-α
Lamers et al. 2012 [127]	111	122	543	AD higher IL-6 + CRP + TNF-α than MD + C
Karlovic et al. 2012 [128]	32	23	18	MD + AD higher IL-6 + CRP than C no difference in TNF-α
HPA-axis dysregulation
Nelson et al. 1997 [110]	662	6171	-	MD more DST non-suppression than AD
Anisman et al. 1999 [123]	17	31	27	AD lower cortisol than C
Wong et al. 2000 [129]	10	-	14	MD higher cortisol than C
Kaestner et al. 2005 [124]	21	161	37	MD higher cortisol than AD + C
Lamers et al. 2012 [127]	66	82	393	MD higher cortisol than AD + C
Karlovic et al. 2012 [128]	32	23	18	MD higher cortisol than AD + C

¹ Atypical depression was assessed as the absence of melancholic depression (non-melancholic depression).

AD, Atypical depression; C, Healthy controls; CRP, C-reactive protein; DST, Dexamethasone suppression test; IL, Interleukin; MD, Melancholic depression; MetS, Metabolic syndrome; TNF, Tumor necrosis factor.