Maximum acid output and risk of peptic ulcer.

The relationship between the capacity to secrete acid and the risk of peptic ulcer has been examined prospectively in 114 healthy symptom-free students and retrospectively in 2361 patients with and without ulcers. The risk of ulcer was found to increase as te maximum acid output (M.A.O.) increased, and the risk of recurrent ulceration, after vagotomy and drainage for duodenal ulceration, was found to increase as the postvagotomy M.A.O. increased. The risk of recurrent ulcer, at any postvagotomy M.A.O., was always greater than the risk of ulceration in a healthy individual with an equivalent M.A.O.. The addition of an antrectomy to a vagotomy restored the risk of recurrent ulcer towards that of a healthy individual developing his first ulcer. The therapeutic benefit of adding an antrectomy to a vagotomy could not be attributed solely to its enhancement of the percentage reduction in M.A.O. from 65% to 95%. The major therapeutic effect of an antrectomy seems to be achieved independently of its action on M.A.O.