Article Impact Level: HIGH Data Quality: STRONG Summary of J Epidemiol Community Health. https://doi.org/10.1136/jech-2024-222114 Dr. Aya Bardugo et al.
Points
- A nationwide cohort study in Israel examined the link between cognitive function in adolescence and the risk of early-onset stroke in 1,741,345 adolescents aged 16-20 years, tracked from 1987 to 2012.
- Adolescents were categorized into three cognitive function levels: low (IQ below 89), medium (IQ 89-118), and high (IQ above 118), and followed through the Israeli National Stroke Registry from 2014 to 2018.
- During the follow-up, 908 first stroke events were recorded (767 ischemic and 141 hemorrhagic). Compared to the high cognitive function group, the medium cognitive function group had a hazard ratio (HR) of 1.78, and the low cognitive function group had an HR of 2.68 for early-onset stroke.
- Each unit decrease in cognitive function z-score correlated with a 33% increased stroke risk (HR: 1.33). These findings were consistent even when accounting for diabetes and hypertension and were robust for ischemic strokes, especially in individuals younger than 40 years.
- Lower cognitive function in adolescence is a significant risk factor for early-onset stroke, alongside other factors like obesity and hypertension. Early cognitive assessments could be vital in identifying and mitigating stroke risk factors before adulthood.
Summary
In a comprehensive nationwide cohort study, researchers examined the link between cognitive function in adolescence and the risk of early-onset stroke. Conducted on 1,741,345 Israeli adolescents (42% women) who underwent cognitive assessments at ages 16-20 years before mandatory military service between 1987 and 2012, the study categorized cognitive function into three levels: low (IQ score below 89), medium (IQ score 89-118), and high (IQ score above 118). These adolescents were then tracked through the Israeli National Stroke Registry, with stroke incidence measured from 2014 to 2018 using Cox proportional hazard models to determine the risk associated with each cognitive level.
During the follow-up period, encompassing 8,689,329 person-years and extending to a maximum age of 50 years, there were 908 first stroke events recorded, of which 767 were ischemic and 141 hemorrhagic. The analysis revealed that compared to those with high cognitive function, individuals in the medium cognitive function category had a hazard ratio (HR) for the early-onset stroke of 1.78 (95% CI: 1.33-2.38), while those in the low cognitive function category had an HR of 2.68 (95% CI: 1.96-3.67). Notably, there was a significant dose-response relationship, with each unit decrease in cognitive function z-score correlating with a 33% increased stroke risk (HR: 1.33; 95% CI: 1.23-1.42). These findings persisted across sensitivity analyses accounting for diabetes and hypertension, and the associations were robust for ischemic strokes and in individuals younger than 40 years.
The study concluded that lower cognitive function in adolescence, along with other factors like obesity and hypertension, may significantly contribute to the risk of early-onset stroke. This emphasizes the potential of early cognitive assessment as part of a comprehensive strategy to identify and mitigate the risk factors for stroke before adulthood.
Link to the article: https://jech.bmj.com/content/early/2024/05/23/jech-2024-222114
References Bardugo, A., Bendor, C. D., Libruder, C., Lutski, M., Zucker, I., Tsur, A. M., Derazne, E., Yaniv, G., Gardner, R. C., Gerstein, H. C., Cukierman-Yaffe, T., Lebenthal, Y., Batty, D., Tanne, D., Furer, A., Afek, A., & Twig, G. (2024). Cognitive function in adolescence and the risk of early-onset stroke. J Epidemiol Community Health. https://doi.org/10.1136/jech-2024-222114
