The Role of Brachial Pulse Pressure as an Indicator of Intracranial Atherosclerosis: The Atahualpa Project.

Abstract

Carotid siphon calcifications (CSC) are an important imaging marker of systemic atherosclerosis. Routine assessment of asymptomatic CSC may allow the implementation of intervention strategies before catastrophic cerebrovascular events occur. To assess whether brachial PP determinations might independently predicts the presence and severity of CSC in community-dwelling adults. All Atahualpa residents aged ≥40years were invited for the practice of a non-enhanced CT scan of the head, and those who signed the informed consent and had no contraindications for this exam were enrolled. The brachial PP was calculated by subtracting the mean diastolic pressure from the mean systolic pressure obtained from three different readings with individuals in the sitting position. Of 830 eligible candidates, 663 (80%) were included. The mean brachial PP was 56.4±19.9mmHg; 182 persons (27.4%) had PP levels >65mmHg. CT revealed Grade 1 CSC in 356 (54%), Grade 2 in 141 (21%), Grade 3 in 128 (19%), and Grade 4 in 38 (6%) subjects. Predictive margins of PP (delta method) were significantly lower in individuals with Grade 1 CSC than in the other groups. In the best adjusted linear model, PP levels increased up to 11.7mmHg as the severity of CSC increased (β 11.71; 95% C.I. 5.36-18.08: p<0.001). This study provides evidence on the relationship between brachial PP levels and intracranial atherosclerosis. Calculation of the PP may be used for detecting candidates for CT screening, reducing costs during population-based surveys, particularly in remote areas.