March 16, 2015Open Access
View Full PaperNocturnal Blood Pressure in Young Adults and Cognitive Function in Midlife: The Coronary Artery Risk Development in Young Adults (CARDIA) Study
Key Result
Among healthy young adults, the least nocturnal systolic BP dipping was associated with worse executive function in midlife compared to the reference group (β 0.37; P<0.05).
Study Design
Type
Cohort (n=224)
Structured PICO
Does less nocturnal blood pressure dipping and higher nocturnal blood pressure in young adults worsen cognitive function in midlife?
P
Population
224 young adults (mean age 30 years, 55% female, 63% African American) from the CARDIA ambulatory BP monitoring substudy, followed for 20 years.
E
Exposure
Least nocturnal systolic blood pressure dipping (Quartile 4: -7.7% to +56.4%) and higher nocturnal diastolic blood pressure levels
C
Comparator
Reference nocturnal systolic blood pressure dipping (Quartile 3: -13.1% to -7.8%) and lower nocturnal diastolic blood pressure levels
O
Outcome
Cognitive function in midlife assessed by the Stroop test (executive function), Digit Symbol Substitution Test (psychomotor speed), and Rey Auditory Verbal Learning Test (verbal memory) at 20-year follow-upsurrogate
Less nocturnal systolic blood pressure dipping and higher nocturnal diastolic blood pressure in young adulthood are associated with worse executive function in midlife, independent of long-term office blood pressure.
Main Result
Effect estimate: β 0.37
p-value: p=<0.05
Abstract
BACKGROUND: Nocturnal blood pressure (BP) is associated with risk for cardiovascular events. However, the relationship between nocturnal BP in young adults and cognitive function in midlife remains unclear. METHODS: We used data from the ambulatory BP monitoring substudy of the Coronary Artery Risk Development in Young Adults Study, including 224 participants (mean age 30 years, 45% men, 63% African Americans). At the 20-year follow-up, the Stroop test (executive function), Digit Symbol Substitution Test (psychomotor speed), and Rey Auditory Verbal Learning Test (verbal memory) were assessed. RESULTS: Baseline mean office, daytime, and nocturnal BP were 109/73, 120/74, and 107/59 mm Hg, respectively. Nocturnal BP dipping, calculated as (nocturnal systolic BP SBP--daytime SBP) × 100/daytime SBP, was divided into quartiles (Q1: -39.3% to -16.9%; Q2: -16.8% to -13.2%, Q3 reference: -13.1% to -7.8%, and Q4: -7.7% to +56.4%). In multiple regression analyses, the least nocturnal SBP dipping (Q4 vs. reference) and higher nocturnal diastolic BP level were associated with worse Stroop scores, with adjustments for demographic and clinical characteristics, and cumulative exposure to office BP during follow-up (β standard error: 0.37 0.18 and 0.19 0.07, respectively; all P < 0.05). Digit Symbol Substitution Test and Rey Auditory Verbal Learning Test were not significantly associated with nocturnal SBP dipping or nocturnal SBP/diastolic BP levels. CONCLUSIONS: Among healthy young adults, less nocturnal SBP dipping and higher nocturnal diastolic BP levels were associated with lower executive function in midlife, independent of multiple measures of office BP during long-term follow-up.
Cite This Study
Yano et al. (Mon,) conducted a cohort in Healthy young adults (n=224). Least nocturnal systolic BP dipping and higher nocturnal diastolic BP vs. Reference quartile of nocturnal systolic BP dipping (Q3: -13.1% to -7.8%) was evaluated on Stroop test (executive function) score (β 0.37, p=<0.05). Among healthy young adults, the least nocturnal systolic BP dipping was associated with worse executive function in midlife compared to the reference group (β 0.37; P<0.05).