Associação entre eventos estressores e biomarcadores de inflamação em jovens adultos pertencentes à Coorte de nascimentos de 1993, Pelotas, RS

Abstract

Introduction: Stressful events (SEs) are environmental demands of a subjective nature with potential negative effects, such as traumatic events or conflicts. Childhood exposure to SEs is associated with cardiovascular diseases, obesity, diabetes, and mood disorders in adulthood. A documented metabolic response to stressors is the dysregulation of the inflammatory system. Studies have investigated whether circulating inflammatory biomarkers, such as C-reactive protein (CRP) and interleukin6 (IL-6), are related to these events and the development of comorbidities. Among the significant gaps in this field, the latency period between exposure and increased biomarker levels remains a critical unresolved issue. Objective: To investigate the association between exposure to stressful events (SEs) and levels of CRP (C-reactive protein) and IL-6 (interleukin-6) at 18 and 22 years of age, this study analyzed data from the 1993 Pelotas Birth Cohort (Rio Grande do Sul, Brazil), including participants with complete exposure and outcome data (N=2,871 at 18 years; N=2,444 at 22 years). Methods: Exposure to SEs was categorized as a numeric variable (count) and into six groups at 18 years (financial problems, physical abuse, household dysfunction, death, unwanted home/neighborhood relocation, and interpersonal conflicts) and eight groups at 22 years (adding sexual abuse and discrimination). Crude and adjusted linear regression models were applied, adjusting for covariates (sex, race/skin color, household income, SE exposure history, mental health, body mass index, smoking, and alcohol use), analyzing cross-sectional and longitudinal associations, and testing sex-specific interactions. Results: After adjustments, cross-sectional analysis at 18 years showed no significant associations, while at 22 years, exposure to ≥2 SEs in the past year was associated with lower CRP levels. Longitudinal analysis linked financial problems at 18 years to higher CRP levels at 22 years. Sex-stratified analysis revealed that men exposed to 1 SE at 22 years had lower CRP levels, whereas physical abuse at 22 years correlated with higher CRP and IL-6 levels. Among women, unwanted relocation at 18 years was associated with higher IL-6 levels, interpersonal conflicts at 22 years with lower CRP levels, and financial problems at 18 years with higher IL-6 levels at 22 years. Conclusion: These findings suggest that SEs’ impact on inflammation varies by life stage and sex, likely due to psychobiological mechanisms. Future studies should explore biological pathways linking SEs to inflammation, incorporate longitudinal designs to capture latency patterns, and integrate markers (e.g., cortisol) and contextual variables (e.g., social support) to clarify SEs’ long-term health effects.