Longitudinal links between early adolescent temperament and inflammation among young black adults

A large body of research demonstrates that inflammation is involved in physical health problems that cause substantial morbidity and early mortality. Given inflammation's role in the etiology of chronic diseases, pediatric scientists have begun to study childhood factors that presage elevation of inflammatory biomarkers later in life. The purpose of this study was to test hypotheses designed to determine whether early adolescent emotionally intense and low attention temperaments forecast (a) inflammation at ages 25 and 29 years and (b) worsening levels of inflammation between these two data points. Toward this end, 307 Black children from the rural southeastern United States participated in an 18-year longitudinal study (mean age at baseline, 11.2 years) to determine whether and how early adolescent's behavioral styles or emotionally intense and low attention temperaments may be associated with absolute and worsening levels of inflammation in young adulthood. When children were 11-13 years of age, different teachers at each age provided assessments of emotionally intense and low attention temperaments. Thus, multiple measures of the same temperament constructs were obtained across 3 years for each participant. At age 25, participants provided data on their self-regulation abilities. Peripheral blood was collected at ages 25 and 29 years from which inflammation was quantified, using soluble urokinase plasminogen activator (suPAR), the proinflammatory cytokines interleukin (IL) IL-6, IL-10, and tumor necrosis factor-alpha (TNF-α). Covariates associated with inflammation in prior studies were also assessed; these included socioeconomic risk, gender, cigarette smoking, body mass index (BMI), adverse childhood experiences (ACEs), depressive symptoms, and medication use. An early adolescent emotionally intense temperament was associated directly with higher suPAR and cytokine levels at age 29, and with worsening cytokine levels between ages 25 and 29. A low attention temperament was associated with suPAR levels at age 29. Collectively, these observations highlight pathways that could underlie health risks associated with early adolescent temperaments. The findings suggest that emotionally intense and low-attention early adolescent temperaments forecast higher and worsening inflammation levels across young adulthood.