The relevance of continuous blood pressure monitoring in examining the relationship of memory efficiency with blood pressure characteristics

The study of the relationship between hypertension and cognitive decline is characterized by various difficulties of realization and, as a consequence, by incongruent results. One of the reasons for these difficulties may be explained by the occasional method of measurement of blood pressure (once a day). This study presents the results obtained in 27 normotensive and mild hypertensive subjects of both sexes (ages between 20 and 77 years) with a continuous blood pressure monitoring for 24 h. A noninvasive sphygmomanometric technique was used employing a portable recorder programmed to take a measure every 30 min. Both objective and subjective measures of memory, measures of attention efficiency, and IQ were correlated to the blood pressure measures. Continuous monitoring data of blood pressure were analyzed according to a model that included a macroscopic descriptive analysis, a microscopic rhythmometric analysis, and a microscopic integrative analysis where the effects of the interaction between level and duration of excess and the time of the day when the excess eventually appeared were considered. Results evidenced no differences in cognitive efficiency between those subjects identified with the traditional occasional measurement of blood pressure as hypertensives of mild severity and the normal subjects. Cognitive efficiency of our subjects was found correlated, independently from the clinical diagnosis, with the time of peak and with the duration of excess of their blood pressure when the results of the analyses on the continuous monitoring of blood pressure were considered.