Influence of treated blood pressure on progression of silent cerebral infarction

To examine whether treatment for hypertensive patients prevents the progression of cerebral infarction, we performed magnetic resonance imaging (MRI) repeatedly at mean intervals of 22 months on 117 Japanese subjects aged 65-89 (mean 74 years), including 84 hypertensive patients. The patients were given various anti-hypertensive agents, and the blood pressure of each patient was monitored periodically during the observation period. Depending on the average blood pressure at the end of the follow-up period, hypertensive patients were classified into three subgroups: normotension (N), borderline (B) and hypertension (H). None had a prior history of symptomatic cerebral infarction and neurological abnormalities. The number of infarcted lesions were determined on brain MRI by two independent observers.

Silent cerebral infarction (SCI) lesions were observed in 42 hypertensive subjects (50.0%) and in eight control subjects (24.2%) on enrollment. The numbers of SCI lesions increased in 33 hypertensive subjects (39.3%) and three control subjects (9.1%) during the observation period. In the hypertensive subjects, an increased number of infarcted lesions was found in six of 28 subjects in group N (21.4%), 17 of 44 in group B (38.6%), and 10 of 12 in group H (83.3%). Thus, blood pressure controlled to the normal level appears to result in a lower incidence of progression of infarcted areas in patients with hypertension (N versus H, P < 0.001).

Our data indicate that an appropriate anti-hypertensive treatment reduces the risk of a cerebrovascular accident in hypertensive patients.