Galactose elimination capacity and liver volume in aging man

The galactose elimination capacity, a measure of the functional liver cell mass, and liver volume were measured in 50 normal subjects of five different age groups (<50, 51 to 60, 61 to 70, 71 to 80 and >81 years). The volume of the liver was evaluated by ultrasonography. All subjects had normal routine liver function tests and no history of liver disease. Galactose elimination progressively decreased from 3.05 ± 0.58 (S.D.) mmoles per min in younger subjects to 1.83 ± 0.24 mmoles per min in subjects over 81 (p < 0.00003), without any change in the apparent volume of distribution of the sugar. Similarly, the estimated volume of the liver decreased from 110 ± 14 units to 75 ± 13 units with increasing age (p < 0.0002). Both galactose elimination capacity and the estimated liver volume inversely correlated with age (r = 0.728 and r = −0.579, respectively) whereas a positive correlation was observed between galactose elimination and the estimated liver volume (r = 0.520). Part correlation analysis confirmed that age, when entered in a multiple regression already containing body weight and estimated liver volume as independent variables, had a significant effect on liver function, whereas no significant independent effect of liver volume was present. Both age and body weight had a significant independent effect on the estimated liver volume. The maximum functional capacity of the liver, measured by galactose elimination, is reduced in the elderly. Although several factors may play a role, our data suggest that aging is associated with a slight decline in the intrinsic metabolic activity of the hepatic parenchyma.