There are a number of biological features that may distinguish<unk>  from non-psychotic depression. The most significant difference may be the presence of an abnormality in the hypothalamic pituitary adrenal axis (HPA). The HPA axis appears to be dysregulated in<unk> , with dexamethasone suppression tests demonstrating higher levels of cortisol following dexamethasone administration (i.e. lower cortisol suppression). Those with<unk>  also have higher ventricular-brain ratios than those with non-psychotic depression.
Psychotic depression
Depression 
Double depression
Collective depression
Retarded depression
Late life depression
Masked depression
Melancholic depression