Introduction: The etiology of ethanol-associated osteopenia is not fully understood. In order to define the role of ethanol in the pathogenesis of hepatic osteodystrophy, we compared two groups of alcoholic patients with histologically established alcoholic liver disease.
Patients and methods: Twenty-eight patients currently drinking ethanol ("drinkers") and 12 claiming not to have consumed any ethanol for at least six months ("abstainers") were enrolled in the study. In addition, 35 non-alcoholic control subjects without clinical or biochemical evidence of liver disease were also studied. Bone mineral density and various biochemical and hormonal values were measured in each subject; iliac crest biopsies were taken under local anesthesia in the patients and under general anesthesia in the control subjects.
Results: Forearm bone mineral densities, spinal bone mineral densities, and iliac crest cancellous bone areas were significantly lower in the alcoholic patients compared with control subjects (p less than 0.01 for all measurements), but these values did not differ between the drinkers and the abstainers. The drinkers, however, had significantly less osteoblastic activity than the abstainers, as assessed by dynamic bone histomorphometry (p less than 0.001). Serum bone Gla-protein concentrations were higher in the abstainers than in the drinkers (p less than 0.001). No differences were seen relating to histologic parameters of bone resorption, although the alcoholic patients who had lower serum free testosterone concentrations than the control subjects also had higher urinary hydroxyproline excretion rates.
Conclusion: These data suggest that ethanol may be responsible for osteoblastic dysfunction resulting in diminished bone formation and reduced bone mineralization.