Early Cardiovascular Health and Cognitive Function in Young Adulthood: New Insights From Childhood

In this issue of Pediatrics, Salo et al examined whether cardiovascular risk factors beginning in infancy were associated with cognitive function in young adulthood.1 Drawing from the Special Turku Coronary Risk Factor Intervention Project (STRIP), a prospective, randomized trial that provided dietary counseling to families from infancy through early adulthood, the authors followed 1062 children who started the study at 7 months of age in Turku, Finland. Over 20 years, participants underwent repeated assessments of body mass index (BMI), total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol (LDL measured from age 5 years), blood pressure, serum glucose and insulin (measured from age 15 years), and hemoglobin A1c (measured at age 26 years). At the 26-year follow-up, 542 participants (51%) completed a computerized battery of cognitive function tests assessing learning and memory, verbal memory, working memory, reaction time, information processing, and cognitive flexibility.The authors reported that higher BMI, waist circumference, and adverse lipid profiles from childhood through adolescence were associated with lower cognitive performance in young adulthood, particularly in the domain of cognitive flexibility (the ability to shift attention and adapt to changing demands). Higher systolic blood pressure and lower HDL levels during childhood were also associated with lower cognitive flexibility. The authors did not find evidence of associations between glucose and HbA1c and cognitive function. After adjusting for multiple comparisons, associations remained significant between childhood BMI and information processing speed in young adulthood, as well as childhood HDL cholesterol and early adolescence BMI with cognitive flexibility.A notable strength of this study is its longitudinal, prospective design, which spans critical developmental periods from childhood into young adulthood and represents a valuable contribution to lifespan epidemiology research in a pediatric population. Few studies have followed participants from infancy into adulthood with repeated assessments of cardiovascular risk factors. As with all long-running studies, attrition over time presents a challenge. The authors reported that participants who completed the 26-year follow-up were similar to nonparticipants in terms of BMI, blood pressure, and serum lipids, yet these variables reflect only part of the heterogeneity that may differentiate those retained from those lost to follow-up. Long-term participants often differ in meaningful ways, particularly in sociodemographic characteristics such as education and income, which may correlate with both cardiovascular and cognitive outcomes. These characteristics may change over time, as may the environments in which people live and the supports and stressors they encounter, which could influence who remains in follow-up. As such, results should be interpreted in light of potential selection bias and the unmeasured factors that might shape participation, retention, and health outcomes over time. Furthermore, the single time point for measurement of cognitive functioning and the absence of normative data make it challenging to determine cognitive trajectories in relation to the onset of cardiovascular risk factors, determine the clinical significance of relatively lower cognitive performance, or elucidate the potential role of neurocognitive processes in the development of cardiovascular risk, which remain important areas of study.Nonetheless, by extending this work into infancy and across multiple stages of childhood development, Salo et al make a significant contribution to the literature by showing that adverse cardiovascular risk profiles across early life may be associated with lower cognitive function in young adulthood. This builds on a growing body of longitudinal research in adult and older populations that has shown that maintaining high or ideal levels of cardiovascular health across both health behaviors (eg, dietary intake, physical activity) and health factors (eg, BMI, blood pressure) is associated with more favorable cognitive outcomes.2 Notably, these associations in Salo et al’s study were observed in a cognitively healthy, normoglycemic cohort, suggesting that even modest elevations in unfavorable cardiovascular risk factors within clinically acceptable ranges may have implications for cognitive function.While discussing their findings, the authors rightly note that the developing brain is highly sensitive to external influences, reinforcing the importance of primordial risk factors, including cardiovascular risk factors, from the very start of life. Past studies have found associations between early childhood adversities and related socioeconomic and environmental contexts (eg, household and neighborhood factors associated with disadvantage) with both obesity and children’s cognitive development.3–6 Recent studies among children and adolescents have shown the associations between several sociodemographic characteristics (eg, household income, race and ethnicity) as well as neighborhood environmental factors (eg, safety) with cardiometabolic risk factors (eg, HbA1c), cardiovascular health behaviors (eg, physical activity), and overall cardiovascular health.7–11 There is also emerging evidence showing that neighborhoods where children live matter profoundly for cognitive health. Higher neighborhood opportunity, measured by the Child Opportunity Index, a multidimensional measure including education, health and environment, and social and economic domains (eg, access to quality education, stable housing, parks and green spaces), was associated with higher cognitive function in youth.12 In contrast, neighborhood poverty was associated with lower cognitive function in children, and those exposed to socioeconomic adversity were more likely to exhibit disparities in brain structure and development.13,14Findings from Salo et al’s study also underscore the importance of early interventions to promote cardiovascular health during childhood given their potential relevance to cognitive functioning in adulthood. Key questions remain about the role of timing and duration of cardiovascular risk factors in influencing children’s neurocognitive development and later adult cognitive outcomes, making this a rich area for continued study. These associations must also be considered within the complex interplay between social and environmental contexts (eg, poverty, food insecurity) and shared biological and behavioral mechanisms that may shape children’s cardiovascular health and neurocognitive trajectories. This is especially relevant in settings like the United States, where both socioeconomic and racial and ethnic disparities persist in children’s cardiovascular health.Building on the strengths of prospective longitudinal studies like STRIP, future work should engage diverse study populations, integrate theory-driven approaches and rigorous methodological designs, and capture contextual factors shaping children’s health and development alongside detailed measures of cardiovascular health and norm-referenced measures of neurocognitive functioning at multiple time points. For clinicians, findings from the study by Salo et al amplify the importance of preventing and managing cardiovascular risk factors during childhood and adolescence, given potential implications for cognitive functioning in early adulthood. In contexts marked by persistent health disparities, cardiovascular health promotion strategies need to also consider and attempt to address patients’ social needs, which can create barriers to care and reduce uptake of health behavior change strategies. Accessible and effective health promotion efforts early in the lifespan may help reduce cardiovascular health disparities and, if the findings from Salo et al’s study are replicated, support cognitive outcomes into adulthood.