Association between ambulatory 24-hour blood pressure levels and cognitive performance: a cross-sectional elderly population-based study.

OBJECTIVE: The aim of this study was to examine the cross-sectional association between ambulatory 24-h blood pressure levels and cognitive performance while considering the effects of potential confounders among community-dwelling adults aged 65 years and older. METHODS: Based on a cross-sectional design, 1011 subjects (mean age 66.2 +/- 0.8 years; 60.2% women) were recruited prospectively. Average levels of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were computed for a 24-h period. Cognitive performance was assessed by Folstein's Mini-Mental State Examination, immediate and delay recall subtests of the French version of the Free and Cued Selective Reminding Test, and Trail Making Test A and B. Age at baseline evaluation, gender, education level, anxiety, depression, cardiovascular risk factors, antihypertensive drugs use, and body mass index were used as confounders in data analysis. RESULTS: Multivariate logistic regression showed that, compared with low DBP level (i.e., <80 mmHg) used as reference value, only a high DBP level (i.e., >or=90 mmHg) was significantly associated with lower performance in immediate recall (adjusted odds ratio [OR] = 2.7 [1.3;5.9] for full model, and adjusted OR = 2.6 [1.2;5.4] for the stepwise backward model). Furthermore, the stepwise backward selection showed that male gender (adjusted OR = 2.2 [1.4;3.3]) and depression (adjusted OR = 2.4 [1.3;4.6]) were also significantly associated with low performance in immediate recall, whereas a high education level was associated with high performance (adjusted OR = 0.9 [0.8;0.9]). CONCLUSIONS: The findings show that only high DBP was associated with lower episodic memory performance compared with low DBP level in the studied sample. Further research is needed to corroborate and explain this finding.