Major depression and immunity in alcohol-dependent persons

Altered immunity has been associated with both alcoholism and major depression (MD). We investigated the contribution of MD, as well as alcoholism, to in vitro measures of immunity in inner-city alcohol-dependent (SCID-DSM-III-R) persons and community nonabusers, all otherwise in good health.

Alcohol-dependent persons at an ambulatory alcohol treatment center who did not abuse other substances were studied along with the comparison sample (total n=122). Enumerative and functional immune measures included leukocyte and lymphocyte subsets, mitogen response, natural killer cell activity (NKCA), and granulocytic phagocytosis.

Controlling for alcohol dependence, age, gender, racial background, and medical status, MD was associated with decreased phytohemagglutinin (PHA) responses (p<.03), possibly decreased NKCA (p<.08), and increased circulating monocytes (p<.04). Controlling for MD, age, gender, racial background, and medical status, alcohol dependence was associated with decreased circulating B lymphocytes (p<.02), possibly decreased CD56+ (NK) cells (p<.06), and increased monocytes (p<.04). Responses to concanavalin A and pokeweed mitogen, granulocyte functions, and the composition of other leukocyte and lymphocyte subsets showed no evidence of being associated with MD or with alcoholism (p>.1). Secondary analyses exploring factors such as recent alcohol use, cigarette use, and nutrition suggested that these factors accounted for the altered lymphocyte subsets associated with alcoholism and the possibly decreased NKCA with MD. They did not account for the association of MD with increased monocytes and decreased PHA.

MD-associated immune changes in alcoholics are modest and consistent with those seen in MD without alcoholism. Some MD- and many alcoholism-associated immune effects appear related to factors such as cigarette use and recent alcohol exposure.