GASTRIC-EMPTYING AND FIRST-PASS METABOLISM OF ETHANOL IN ELDERLY SUBJECTS WITH AND WITHOUT ATROPHIC GASTRITIS

Background: Oral ethanol intake results in lower blood ethanol concent rations than intravenous administration of the same dose of ethanol. T his first-pass metabolism is thought to be due to gastric metabolism o f ethanol via alcohol dehydrogenase and also to hepatic first-pass met abolism. Methods: Since a loss of gastric mucosa may decrease first-pa ss metabolism of ethanol, this metabolism was studied in 10 elderly su bjects (6 women and 4 men) with atrophic gastritis and bacterial overg rowth and in 17 control subjects with normal gastric secretory functio n. Atrophic gastritis was verified by means of the serum pepsinogen I to pepsinogen II ratio and the hypochlorhydria occurring after pentaga strin stimulation. Bacterial overgrowth was assessed by bacterial coun ts in gastric juice. The study was repeated after tetracycline treatme nt to decrease gastric bacteria. In addition, gastric emptying rates o f ethanol solution with technetium-99m sulfur colloid were calculated from scintigraphic images. Furthermore, gastric biopsy specimens were taken from 12 female patients with atrophic gastritis and from 12 cont rols for determination of alcohol dehydrogenase activity. Results: Nei ther gender (female versus male, 28 +/- 5% versus 42 +/- 5%), atrophic gastritis (normal versus atrophic gastritis, 35 +/- 4% versus 32 +/- 6%), nor tetracycline treatment in atrophic gastritis subjects (before versus after, 32 +/- 6% versus 41 +/- 5%) had a statistically signifi cant effect on the first-pass metabolism of ethanol in the elderly. Ga stric alcohol dehydrogenase activity was significantly lower in atroph ic gastritis subjects than in controls (p < 0.01). A significant corre lation was found between the first-pass metabolism of ethanol in healt hy controls and gastric half-emptying time (p = 0.032). Conclusions: W e conclude from these data that the rate of gastric emptying modulates first-pass metabolism of ethanol in elderly individuals.