Elevated blood pressure and decreased cognitive function among school-age children and adolescents in the United States

Objective: To evaluate the relationship between elevated blood pressure (BP) and cognitive test performance in a nationally representative sample of children. Study design: The National Health and Nutrition Examination Survey III provides cross-sectional data for children 6 to 16 years, including BP and cognitive test scores. Elevated BP was defined as systolic or diastolic BP ≥90th percentile. Cognitive tests were compared for children with elevated and normal BP. Linear regression was used to evaluate the relation between elevated BP and decreased test scores. Results: Among the 5077 children, 3.4% had systolic BP ≥90th percentile and 1.6% diastolic BP ≥90th percentile. Children with elevated systolic BP had lower average scores compared with normotensive children for digit span (7.9 vs 8.7, P = .01), block design (8.6 vs 9.5, P = .03), and mathematics (89.6 vs 93.8, P = .01). Elevated diastolic BP was associated with lower average scores on block design (9.5 vs 11, P = .01). Linear regression showed that elevated systolic BP was independently associated with lower digit span scores (P = .032). Conclusion: Children with elevation of systolic BP are at risk for central nervous system end-organ damage, as manifested by decreased digit span test scores.