Effects of affective symptoms in adolescence and adulthood on trajectories of cognitive function from middle to late adulthood

Adolescent depressive symptoms and memory performance in young adulthood: Testing critical period, accumulation, and pathway models using a sibling comparison design

RATIONALE

Despite the existing literature connecting depressive symptoms with cognitive function in adulthood, there is limited knowledge about the longitudinal association between depressive symptoms in adolescence and memory function in adulthood, as well as the mechanisms underlying this relationship.

OBJECTIVES

This study aims to determine whether depressive symptoms in adolescence are associated with memory function in young adulthood. To explore the underlying mechanisms of this association, it employs a life course approach, testing the critical period, accumulation, and pathway models.

METHODS

Utilizing data from the sibling sample of the National Longitudinal Study of Adolescent to Adult Health (Add Health), this study employed sibling fixed effects models to control for unobserved heterogeneity at the family level. To test various life course models, the analysis incorporated adult depressive symptoms, as well as an array of behavioral, psychosocial, and educational mechanism variables.

RESULTS

Sibling fixed effects estimates indicated a longitudinal association between depressive symptoms in adolescence and memory function in young adulthood (b = -0.084, p < 0.01). Depressive symptoms in adulthood neither explained nor intensified this association. Mediation analysis revealed that educational attainment modestly accounted for about 11% of the relationship between adolescent depressive symptoms and adult memory function. Combined, these findings lend support to the life course approach, with a specific focus on the critical period model.

CONCLUSIONS

This study's findings suggest that depressive symptoms in adolescence are an independent risk factor for memory function in adulthood. The empirical support for the critical period model underscores the importance of implementing early intervention programs and targeted strategies to support adolescents experiencing depressive symptoms.

The Power of Birth Cohorts to Study Risk Factors for Cognitive Impairment

PURPOSE OF REVIEW

Birth cohorts are studies of people the same time; some of which have continuously followed participants across the life course. These are powerful designs for studying predictors of age-related outcomes, especially when information on predictors is collected before these outcomes are known. This article reviews recent findings from these cohorts for the outcomes of cognitive function, cognitive impairment, and risk of dementia, in relation to prior cognitive function, and social and biological predictors.

RECENT FINDINGS

Cognitive function and impairment are predicted by a wide range of factors, including childhood cognition, education, occupational status and complexity, and biological factors, including genetic and epigenetic. The particular importance of high and rising blood pressure in midlife is highlighted, with some insight into brain mechanisms involved. Some limitations are noted, including sources of bias in the data. Despite these limitations, birth cohorts have provided valuable insights into factors across the life course associated with cognitive impairment.