The liver in 30-year-old individuals with alpha₁-antitrypsin deficiency

Abstract

Objective. Severe (PiZZ) alpha₁-antitrypsin (AAT) deficiency is a risk factor for liver disease, i.e. juvenile cirrhosis in infancy, and cirrhosis and hepatoma in adulthood. Little is known about the risk of liver disease in individuals with moderate (PiSZ) AAT deficiency. To investigate the natural course of AAT deficiency, a cohort of PiZZ and PiSZ individuals identified by the Swedish National neonatal screening programme in 1972–74 is followed regularly. The aim of this study was to compare liver function in this cohort with healthy control subjects aged 30 years. Material and methods. Blood samples were obtained from 89 PiZZ, 40 PiSZ, and 84 control subjects (PiMM), and plasma levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyl (GT) transpeptidase were analysed. Results. The mean values of all liver enzymes were within the normal range in all Pi subgroups. However, the mean AST was higher in the PiZZ and PiSZ subgroups than in the PiMM subgroup (p < 0.001), and the mean ALT was higher in the PiZZ individuals than in the controls (p < 0.05), while GT did not differ significantly among the Pi subgroups. The PiZZ women taking oral contraceptives had higher mean AST and ALT (p < 0.01) and GT (p < 0.05) than the control women taking oral contraceptives. Conclusions. At the age of 30 years, PiZZ and PiSZ individuals have normal plasma levels of the transaminases AST and ALT, although they are significantly higher than those in healthy control subjects. Use of oral contraceptives seems to influence liver enzymes in PiZZ women.

Key Words::

• Alpha₁-antitrypsin deficiency
• liver disease
• liver function
• screening

Acknowledgements

The authors thank Maria Walles for secretarial assistance and Ewa Szemberg for technical assistance. The study was supported by The Swedish Heart-Lung Foundation, The Heart and Lung Association, and The Swedish Society of Medicine.