Relation between stress and cytokine responses in inner-city mothers

Abstract

Background: Women in poor urban neighborhoods have high rates of stress and allergic diseases, but whether stress or stress correlates such as depression promote inflammatory and type 2 cytokine responses is unknown.

Objective: To examine associations among external stressors, perceived stress, depression, and peripheral blood mononuclear cell cytokine responses of mothers enrolled in the Urban Environment and Childhood Asthma Study and test the hypothesis that stress would be positively associated with type 2 and selected proinflammatory (tumor necrosis factor-α and interleukin-8) responses.

Methods: Questionnaire data from mothers living in 4 inner cities included information about external stress, stress perception, and depression. The external stress domains (interpersonal problems, housing, and neighborhood stress) were combined into a Composite Stressor score. Peripheral blood mononuclear cells were stimulated ex vivo and cytokine responses to innate, adaptive, and polyclonal immune stimuli were compared with stress and depression scores for 469 of the 606 study participants.

Results: There were no significant positive associations between Composite Stressor scores, perceived stress, or depression scores and proinflammatory or type 2 cytokine responses, and these findings were not modified by allergy or asthma status. There were some modest associations with individual stressors and cytokine responses, but no consistent relations were noted. Depression was associated with decreased responses to some stimuli, particularly dust mite.

Conclusion: Composite measurements of stressors, perceived stress, or depression were not positively related to proinflammatory or type 2 cytokine responses in these young urban women. These data do not support the hypothesis that these factors promote cytokine responses associated with allergy.

Trial registration: ClinicalTrials.gov, identifier NCT00114881.

Figure 1

Associations between composite stressors and individual stress domains with cytokine responses to innate (A) and adaptive (B) stimuli. Color-coded Pearson partial correlations are adjusted for site, season of blood draw, and mother’s smoking status. Red colors indicate negative associations, while blue colors are indicative of positive associations. The x-axis contains cytokine responses. The y-axis contains stimulants. Abbreviations for the stimulants and cytokines are listed in Table 2. Correlation coefficients are shown for correlations significant at p<0.05.

Figure 2

Associations between depression/perceived stress and cytokine responses to innate (A) and adaptive (B) stimuli. Color-coded Pearson partial correlations are adjusted for site, season of blood draw, and mother’s smoking status. Red colors indicate negative associations, while blue colors are indicative of positive associations. The x-axis contains cytokine responses. The y-axis contains stimulants. Abbreviations for the stimulants and cytokines are listed in Table 2. Correlation coefficients are shown for correlations significant at p<0.05.