Effect of Anger Patterns and Depression on Serum IgA and NK Cell Frequency

There are conflicting findings about relationship between depression and anger with immunological parameters.

To investigate the relationship between anger patterns and immune system in depressed patients.

Thirty-five patients with major depressive disorder were selected according to DSM-IV criteria. The Hamilton Depression Scale and Spielberger Anger questionnaires were used to determine severity of depression and "anger expression pattern", respectively. The control group without a previous history of mental illness was also selected. In the group of patients with moderate depression, serum IgA levels and NK cell percentage were measured.

Mean differences of all types of "anger expression pattern", including; "state-trait anger", "anger expression out", "anger expression in", "anger control out" and "anger control in", between study and control groups, were statistically significant (p<0.05). Difference in mean serum levels of IgA in either group was not significant (p=0.9), but the mean difference was significant in terms of NK-cell percentage in both groups (p=0.04). There was no significant relationship between IgA levels and percentage of NK- cell with all types of "anger expression pattern" in both groups. Only in the control group, IgA had significant correlation with anger control out (p=0.04).

Moderately depressed patients versus control group had higher Spielberger scores in all types of anger expression pattern except anger control-out and anger control-in. We found no evidence supporting the relationship between" anger expression pattern" and IgA levels and NK cell percentage; however, it seems that depression itself causes reduced number of NK cells and increased IgA levels.