Hypertensive renovasculopathies and the rise of blood pressure with age in Japan and USA.

Arterial intimal fibroplasia in renal interlobular arteries but not arteriolar hyalinization was reported to be proportional to the rise of blood pressure with age in the data from all populations examined so far. New findings from Japan offer further insights into the disparities between the two types of renovasculopathy, both of which are called by the same name, 'arteriolosclerosis'. PAS stained paraffin sections were prepared from specimens obtained at autopsy in Tokyo and New Orleans, emphasizing basal subjects, i.e. those with no cause of death known to be related to hypertension. Severities of fibroplastic vasculopathy, in units of intimal thickness as % of outer diameter, and hyaline vasculopathy, in units of affected arterioles per cm2 of tissue sectional area, were measured morphometrically. Blood pressure data were taken from published population surveys. Fibroplastic renovasculopathy was found to provide a proxy for mean blood pressure (MBP) when comparing groups of men and women of various age groups in the USA and Japan. Hyaline renovasculopathy did not reproduce these patterns. Some of these findings confirm similar results from prior studies, and this reproducibility increases confidence that a true biological difference may exist between these populations.