IMPAIRED INVIVO IMMUNE-RESPONSES IN PATIENTS WITH MELANCHOLIA

Previous attempts to establish a relationship between impaired cell-me diated immunity (CMI) and major mood disorders have been limited by a failure to explore the relevance of depressive subcategories or to ass ess CMI by in vivo methods. In this case-control study CMI was assesse d in 57 patients with major depression (31 with melancholic, 26 with n on-melancholic disorders), and in age- and sex-matched controls by bot h in vitro and in vivo immunological techniques. Compared with control subjects and patients with non-melancholic depression, patients with melancholia demonstrated reduced in vivo CMI as assessed by delayed-ty pe hypersensitivity (DTH) skin responses. Although increasing age, sev erity of depression, hospital admission for treatment, and reported we ight loss are correlates of melancholia, none of these factors alone, or in combination, accounted for the differences in DTH responses obse rved between the two depressive subtypes. These data suggest that impa ired CMI in vivo may be limited to those with melancholic disorders. A t this stage the factors which account for this effect are unclear.