This study investigated the relationships of the serum markers of fibrogenesis and basement membrane formation to the clinical and morphological severity of alcoholic liver disease and to the degree of alcohol abuse. The concentrations of the aminoterminal propeptide of type III collagen, type IV collagen, and laminin were measured from 87 samples representing a wide range of clinical and histological severities of the disease, which were assessed with indices that have been shown to correlate well with the risk of dying within 1 yr. Significant correlations (p less than 0.00001) were found between the markers of connective tissue metabolism and the Combined Clinical and Laboratory Index: (aminoterminal propeptide of type III collagen, rs = 0.82; type IV collagen, rs = 0.82; laminin, rs = 0.81), as well as between these markers and the Combined Morphological Index: (aminoterminal propeptide of type III collagen, rs = 0.70; type IV collagen, rs = 0.68; laminin, rs = 0.64). Whereas the patients with less than 8 mM of alcohol in their morning urine (mild or moderate drinkers) showed a significant (p less than 0.00001) decrease in these markers in a period of 27 +/- 1 wk, the patients with more than 8 mM of urinary alcohol (heavy drinkers) had no improvement. It is proposed that both fibrogenesis and basement membrane formation are associated with disease severity, degree of alcoholic hepatitis, and alcohol intake, which are important determinants of prognosis in alcoholic liver disease.