[Relationship between stressful events and inflammatory markers in young adults from the 1993 Pelotas (Brazil) birth cohort].

Chronic stress is associated with various morbidities, but the physiological effects require greater understanding, especially with regards to inflammatory biomarkers. This study investigated the association between stressful events and mean levels of C-reactive protein (CRP) and interleukin-6 (IL-6) in both cross-sectional (at ages 18 and 22) and longitudinal (exposure at age 18 and outcome at age 22) analyses. Participants from the 1993 Pelotas (Brazil) birth cohort with complete data at both ages were included (n = 2,871 at age 18; n = 2,444 at age 22). Exposure was assessed as the number of stressful events (none, 1, ≥ 2) and by stressful events group (6 groups at age 18; 8 groups at age 22). Linear regression models were used for the determination of associations, including the analysis of interactions with sex. Unstratified associations were either null or conflicting. Cross-sectional associations were observed after stratification by sex: at 22 years of age, men exposed to physical abuse had higher levels of CRP (β logCRP: 0.41, 95%CI: 0.04; 0.78) and IL-6 (β logIL-6: 0.26, 95%CI: 0.06; 0.46) than those not exposed; at 18 years of age, women exposed to unwanted changes had higher IL-6 levels (β: 0.15, 95%CI: 0.02; 0.28), while at 22 years of age, those with relationship problems had lower CRP levels (β: -0.15, 95%CI: -0.29; -0.01) compared to those not exposed. The results suggest that the impact of stressful events on inflammation varies according to the type of event, age, and sex, possibly reflecting differences in biopsychological mechanisms.