Hippocampal atrophy, whole brain volume, and white matter lesions in older hypertensive subjects

Objective: To determine the potential role of whole brain atrophy, hippocampal atrophy, or both, and small vessel disease/white matter lesions as mechanisms underlying the cognitive impairment associated with hypertension. Methods: Using MRI scanning the authors determined hippocampal volumes, whole brain volumes, and location and severity of white matter lesions, using Scheltens scale, in 103 hypertensive (166 +/- 8/88 +/- 7 mm Hg, 54 female) and 51 normotensive (132 +/- 12/74 +/- 7 mm Hg, 21 female) subjects age greater than or equal to 70 years. Results: Compared to normotensive subjects, older hypertensive subjects had significantly smaller whole brain volumes (887 +/- 109 vs 930 +/- 97 cm(3), p = 0.02) and nonsignificantly reduced hippocampal volumes (5.39 +/- 1.60 vs 5.67 +/- 1.80 cm(3), p = 0.33). Hypertensive subjects had an increased burden of periventricular lesions: bands (p = 0.03), frontal caps (p = 0.08), occipital caps (p = 0.07), and total periventricular hyperintensities (p = 0.02). They also had higher scores in subcortical areas: frontal (p = 0.04), temporal (p = 0.03), and deep white matter areas (p = 0.05). A correlation was found between whole brain volumes and systolic blood pressure (r = -0.19, p = 0.02). No correlation was seen between whole brain volumes and white matter lesion burden. Conclusions: Moderate hypertension in non-impaired older subjects is associated with smaller whole brain volume and an increased burden of subcortical and periventricular white matter lesions.