Mean affect and affect variability may interact to predict inflammation

• Published in: Brain, behavior, and immunity behavior, and immunity, 2023-03, Vol.109, p.168-174
• Main Authors: Jones, Dusti R., Ruiz, John M., Schreier, Hannah M.C., Allison, Matthew A., Uchino, Burt N., Russell, Michael A., Taylor, Daniel J., Smith, Timothy W., Smyth, Joshua M.
• Format: Article
• Language: English
• Subjects: Adult; Affect - physiology; Affect dynamics; Cytokines; Ecological Momentary Assessment; Emotion variability; Female; Humans; Inflammation; Interleukin-6; Male; Negative emotion; Positive emotion; Tumor Necrosis Factor-alpha; Young Adult
• ISSN: 0889-1591; 1090-2139
• DOI: 10.1016/j.bbi.2023.01.008

•Average levels of affect are not linked with inflammatory markers.•Average negative affect moderates the association of negative affect variability and TNF-α.•Average positive affect moderates the association of positive affect variability and IL-6.•Those with high and unstable positive and negative affect may have higher inflammation. Individuals with greater affect variability (i.e., moment-to-moment fluctuations possibly reflecting emotional dysregulation) are at risk for greater systemic inflammation, which is associated with cardiovascular disease. Some evidence suggests that affect variability is linked with poorer health indicators only among those with higher average levels of affect, particularly for positive affect (PA), and that associations may be non-linear. The present study sought to examine whether links between both PA and negative affect (NA) variability and inflammation are moderated by average level of affect. Participants (N = 300, 50 % female, ages 21–70, 60 % non-Hispanic White, 19 % Hispanic, 15 % non-Hispanic Black) completed a lab assessment and provided a blood sample to measure systemic inflammation (i.e., TNF-α, IL-6, CRP). Affect was collected via a two-day ecological momentary assessment protocol where reports were collected about every 45-min during waking hours. Momentary affect ratings were averaged across both days (i.e., iM), separately for PA and NA, for each participant. Affect variability was calculated as the person-specific SD (i.e., iSD) of affect reports, separately for PA and NA. Linear and quadratic interactions were tested. Models included covariates for sex, race, and body mass index. There were significant interactions between NA iM and NA iSD predicting TNF-α (b = 6.54; p