Background: Elevated blood pressure (BP) is a risk factor for cognitive impairment.
Objective: We aim to explore the association between the duration of hypertension in early adulthood, with cognitive function in midlife. Furthermore, we investigate whether this asssociation is altered among participants with controlled BP.
Methods: This prospective study included 2,718 adults aged 18-30 years without hypertension at baseline who participated in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Duration of hypertension was calculated based on repeat measurements of BP performed at 2, 5, 7, 10, 15, 20, and 25 years after baseline. Cognitive function was assessed at Year-25 using the Rey Auditory Verbal Learning Test (RAVLT), Digit Symbol Substitution Test (DSST), and Stroop test.
Results: After multivariable adjustment, a longer hypertension duration was associated with worse verbal memory (RAVLT, p trend = 0.002) but not with processing speed (DSST, p trend = 0.112) and executive function (Stroop test, p trend = 0.975). Among subgroups of participants with controlled (BP < 140/90 mmHg) and uncontrolled (SBP≥140 mmHg or DBP≥90 mmHg) BP at the time of cognitive assessment (i.e., Year-25 BP), longer duration of hypertension was associated with worse verbal memory. Similar results were observed in subgroups with controlled and uncontrolled average BP prior to cognitive assessment.
Conclusion: Longer duration of hypertension during early adulthood is associated with worse verbal memory in midlife regardless of current or long-term BP control status. The potential risk of hypertension associated cognitive decline should not be overlooked in individuals with a long duration of hypertension, even if BP levels are controlled.
Keywords: Cognitive function; DSST; RAVLT; duration; hypertension; stroop test.