Abstract
BACKGROUND: Disagreement exists on the association between changes in blood pressure and cognitive impairment. We aimed to examine whether 4-year changes in systolic and diastolic blood pressure (SBP and DBP) are associated with cognitive status in a representative sample of older men and women. METHODS: Analysis of longitudinal data from 854 participants of a population-based German sample (aged 60-87 years) was performed with standard cognitive screening and blood pressure measurements. Effects of changes in SBP and DBP (10 mmHg and 5 mmHg respectively as unit of regression effect measure) on cognitive status were evaluated using non-parametric and linear regression modeling. RESULTS: No clear associations were seen between changes in SBP or in DBP and cognitive scores. Small effects were found after stratification for sex and hypertension awareness. Specifically, larger decreases in SBP were associated with higher cognitive scores in those men aware of their hypertension (10 mmHg decrease in SBP, β = -0.26, 95% CI: -0.51 to -0.02) and men with controlled hypertension (10 mmHg decrease in SBP, β = -0.44, 95% CI: -0.92 to -0.03). Additionally larger increases in DBP were associated with higher cognitive scores in men with controlled hypertension (5 mmHg increase in DBP, β = 0.67, 95% CI: 0.19-1.15). For women aware of their hypertension, larger decreases in DBP were associated with higher cognitive scores (5 mmHg decrease in DBP, β = -0.26; 95%CI: -0.51 to -0.01). CONCLUSIONS: Changes in blood pressure were only weakly associated with cognitive status. Specifically, decreases in SBP were associated with higher cognitive scores in men aware of their hypertension and especially those that were medically controlled.