Increasing hepatic arteriole wall thickness and decreased luminal diameter occur with increasing age in normal livers

Background & aims: There is no data to suggest that the size of bile ducts, portal venules, and hepatic arterioles varies according to age in the normal human liver. We sought to examine whether hepatic arteriolar size, wall thickness, and luminal diameter change with increasing age.

Methods: Histologically normal liver specimens from 90 live and deceased donors were separated into three groups of thirty: donor age<30, 31-60, and>60years old. Trichrome-stained slides were de-identified and assessed by a liver pathologist blinded to donor age. Morphometric measurements were taken of the hepatic arteriole, the cross-sectional diameter, and its wall thickness. The arteriole was measured at its widest diameter, the arteriolar wall at its thickest portion, and the luminal diameter between its widest points.

Results: There was no difference in number of arterioles or bile ducts or in arteriolar cross-sectional diameter among the groups and no correlation with age was found. An increasing arteriolar wall thickness and a decrease in luminal diameter with advancing age were noted; no difference in bile duct size among the groups was found. There was a significant difference in wall thickness/total cross-sectional diameter with extremes in age (21-30 age group vs. 71-80 age group, p=0.0009) with an accompanying significant decrease in luminal diameter/cross-sectional diameter between the same groups (p=0.00002).

Conclusions: Increasing hepatic arteriolar wall thickness and decreased arteriolar cross-sectional diameter occur with increasing age in the normal human liver.