A randomized controlled trial of β-blockers versus endoscopic band ligation for primary prophylaxis: A large sample size is required to show a difference in bleeding rates

Primary prophylaxis with nonselective beta-blockers in high-risk subjects has been shown to be effective in reducing both esophageal variceal bleeding and mortality. Recently it has been suggested that band ligation may be a better option for primary prophylaxis. We compared nonselective beta-blockers with band ligation in patients with large varices (F2, F3) and elevated hepatic venous wedge pressure gradient (HVWPG, greater than or equal to 12 mm Hg). All patients were prospectively followed for variceal bleeding, mortality, and treatment-related complications. Based on previous published studies, we estimated that 90 patients in each arm would be required to show a difference in bleeding rate. The study was prematurely terminated when we realized that our estimated sample size was inadequate to show a difference based on the observed bleeding rate. At the time of termination, 31 patients ( Child A, 11; B, 14; C, 6), with a mean HVWPG of 19 +/- 9.1 mm Hg, were randomized to either band ligation ( group A; n = 16) or beta-blockers ( group B; n = 15). Baseline demographics of both groups were similar and the mean follow-up period was 27.4 +/- 12.9 months. During the follow-up, two patients in group A and one patient in group B had bleeding. Nine patients (29%; group A, six; group B, three; P = ns) died due to non-bleeding-related causes and five (16%) patients ( group A, three; group B, two) underwent liver transplantation. Treatment-related complication were minimal in both groups. Despite the selection of high-risk patients, the observed bleeding rate was much lower than anticipated. Based on our observed bleeding rates, 424 patients would be required in each arm to show a difference between band ligation and beta-blocker therapy.