Figure 2: Vector analysis of the pair of variables “systolic blood pressure; diastolic blood pressure.” The points and the 95% confidence ellipses represent the mean values of systolic and diastolic pressure among subjects with cognitive reserve index ≥94 (●) and <94 , the cut-off of 94 representing the median of this continuous variable for this cohort. The vector of impairment (arrow) is directed towards significantly higher values of systolic (+6 mmHg) and lower values of diastolic (−1 mmHg).