Relationship between brain atrophy estimated by a longitudinal computed tomography study and blood pressure control in patients with essential hypertension

To evaluate the relationship between blood pressure control and the progres sion of brain atrophy in the elderly, patients with essential hypertension and brain atrophy were longitudinally evaluated using computerized tomograp hy (CT). The study evaluated 48 patients with essential hypertension aged 4 6-78 years, and 30 sex- and age-matched normotensive control subjects. The extent of brain atrophy as determined by caudate head index (CHI), the inve rse cella media index (iCMI), and Evans' ratio (ER) was estimated twice at an interval of 5-9 years (mean, 6.9 years). The mean annual increases in CH I (Delta CHI), iCMI (Delta iCMI), and ER (Delta ER) were evaluated. Mean bl ood volume in the common carotid artery (BF) and the decrease in BF per yea r (Delta BF) were also determined. The Delta CHI, Delta iCMI, and Delta ER increased with age in the hypertensive subjects as well as the control grou p across all age groups evaluated. The Delta CHI, Delta iCMI, and Delta ER were significantly greater in the patients with essential hypertension in t heir 50 s as compared with the controls. In patients with essential hyperte nsion aged 65 years or older, the Delta CHI, Delta iCMI, and Delta ER were significantly lower in the group in whom the blood pressure was controlled within the range of borderline hypertension than the groups in which it was controlled in the range of normal or mild hypertension. In the younger pat ients under the age of 65 with essential hypertension, blood pressure contr ol did not affect the Delta CHI, Delta iCMI, and Delta ER. The Delta CHI, D elta iCMI, and Delta ER were significantly correlated with Delta BF in both groups. These findings indicate that control of systolic blood pressure wi thin the range of borderline hypertension may delay the progression of brai n atrophy in elderly patients with essential hypertension.