A 5-year follow-up of ambulatory blood pressure in healthy older adults.
BACKGROUND
This study assessed 5-year changes in ambulatory blood pressure (ABP) in healthy, older individuals and determined the extent to which it could be predicted from earlier BP measures and other cardiovascular risk factors.


METHODS
A total of 162 men and women, aged 55 to 79 years, with no prior medical disorders, completed a medical examination and two 24-h ABP sessions. The procedures were repeated 5 years later in 80% (130) of these subjects. A modified hierarchical regression analysis was used to determine whether initial ABP and casual blood pressure (CBP) measures and demographic and physical examination data could predict ABP in 5 years.


RESULTS
The CBP and most ABP levels during waking and sleep increased after 5 years. However, CBP remained in the normotensive range for 73% of the subjects. The ABP variability tended to decrease over time. The ABP and CBP measures accounted for at least 50% of the variance in the prediction of ABP level after 5 years. In comparison, the predictability of ABP variability was quite low, particularly during sleep (<30% of the variance accounted for).


CONCLUSIONS
The ABP and CBP were good predictors of future ABP level in healthy older subjects, but ABP variability was more difficult to predict. Except for age, none of the standard cardiovascular risk factors contributed significantly to the prediction of ABP level or variability.