Major Depressive Disorder and Immunity

Is there immune dysfunction in depressive disorders?

“…In the larger study recently reported by Schleifer et al (1989), the investigators found no statistically significant differences between patients and well-matched controls on a range of in vitro cellular immune responses. This sample again consisted mainly of young out-patients.…”

“…Such cells are thought to play a vital role in the body's defences against viral infections and neoplasms (Ritz, 1989), so that a deficit in NK cell activity in depressed patients may have clinical significance. Schleifer et al (1989) failed to detect differences in NK cell activity in their large study but, given the demographic and diagnostic limitations of their sample, these results should not be considered definitive. By contrast, Irwin et al (1987) found impaired NK cell activity in a casecontrol study of 19 unmedicated men hospitalized with depression, while Urch et al (1988) reported that NK cell activity and antibody-dependent cellular cytotoxicity were impaired in both unmedicated and medicated depressed patients.…”

“…Dismissal of any association between depression and immune dysfunction may seem justified by a cursory reading of the report of Schleifer et al (1989) who, in the largest study of its kind, found no substantive differences in humoral or cell-mediated immunity (CMI) between 91 unmedicated patients with major depressive disorder and matched control subjects. It is therefore timely to consider whether 'psychoimmunology' should now be 'cut out and thrown away without any harm being done' (Hall, 1987) or whether methodological issues have obscured important positive findings.…”

“…In summary, although the 1989 report by Schleifer et al is undoubtedly the most important investigation yet published in this area, it does not allow a critical evaluation of the fundamental question: is immunological dysfunction largely confined to a depressive sub-type, namely those patients with endogenous depression? Stein (1989), a co-worker of Schleifer, has recently conceded that 'altered immune system measures... may occur in subgroups of depressed patients'.…”

Chronic stress alters the immune response to influenza virus vaccine in older adults.

“…Not (31,32). Age-related immunological declines are related to the increased vulnerability to infectious illness among the elderly (8,10,25).…”