The New England Journal of
Medicine -- April 1, 1999 -- Vol. 340, No.
13
Primary Prevention of Bleeding from Esophageal
Varices
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- Most patients with portal hypertension in
North America and Europe have cirrhosis. Of those with compensated
cirrhosis (i.e., cirrhosis with no ascites, encephalopathy, or
severe jaundice), 30 percent have esophageal varices, as compared
with 60 percent of those with decompensated cirrhosis. (1) The risk of a first episode of bleeding from
esophageal varices is higher among patients with cirrhosis who have
severe liver dysfunction and those whose varices are large or have
red signs -- so-called varices on varices -- identified
endoscopically. (2) Patients with cirrhosis
may also have bleeding due to portal hypertensive gastropathy,
nonvariceal mucosal abnormalities seen on endoscopy. These
abnormalities account for at least 10 percent of first bleeding
episodes. (2)
The mortality due to bleeding among these patients is high: between
30 percent and 50 percent die within six weeks of the first
bleeding episode. (1)
This dismal outcome has led to attempts
both to identify those at high risk for bleeding and to prevent
bleeding. Initial studies of the endoscopic characteristics
originally thought to predict variceal bleeding -- such as the
presence of large varices or the presence of red signs (3) -- proved to overestimate the risk of bleeding.
In one subsequent study in which the severity of liver disease was
assessed by modified Child's criteria (with the classification
based on ascites, encephalopathy, serum albumin and bilirubin
concentrations, and prothrombin time), only 19 percent of 321
patients in the two categories at highest risk had an incidence of
bleeding of 40 percent or more one year after initial endoscopy.
(2) In another study, which included patients
with cirrhosis who had varices at high risk as determined by
endoscopy, only 18 percent of these patients had varices that bled
within one year. (4)
Further data related to the risk of
bleeding have come from studies of untreated groups in randomized
trials designed to assess methods for the prevention of the first
bleeding episode. Two therapies have been used for the prevention
of first bleeding from varices: beta-adrenergic-antagonist drugs
and variceal obliteration. Propranolol or nadolol has been compared
with no active therapy or placebo in nine studies. A meta-analysis
(5) found that the drugs reduced the
incidence of bleeding, with a pooled odds ratio of 0.5 (95 percent
confidence interval, 0.4 to 0.7); an average of 11 patients
required treatment in order to prevent one episode of bleeding. The
mortality rate was lower in the treatment group in all but one
study. (5) The results of a second
meta-analysis, (6) of data on 589
patients with at least medium-sized but mostly large varices
(diameter, greater than or equal to 5 mm), all followed for two
years, revealed an actuarial rate of bleeding of 22 percent among
the patients treated with a beta-adrenergic-antagonist drug, as
compared with 35 percent among the untreated patients (P=0.002).
The rate of fatal bleeding was also lower among the treated
patients (P=0.01), but overall survival was not.(6) The addition of
isosorbide mononitrate may improve the effectiveness of medical
therapy: in patients with red signs on their varices, irrespective
of the size of the varices, or with varices 5 mm or more in
diameter, bleeding occurred after an average follow-up of 30 months
in 6 percent of patients treated with nadolol and isosorbide
mononitrate and in 14 percent of those treated with nadolol alone.
(7)
The other treatment option is endoscopic
sclerotherapy, which has been compared with no treatment in 20
randomized trials that included 1756 patients, most of whom had
either medium-sized or large varices. (5) In
the sclerotherapy groups there was a significant reduction in
bleeding in 5 trials, an increase in bleeding in 2 trials, and no
difference in 13 trials. Although the pooled odds ratio for
bleeding was 0.6 (95 percent confidence interval, 0.5 to 0.7),
there was significant heterogeneity in the results with regard to
bleeding and mortality among the different trials (P<0.001). (5) For example, the Veterans Affairs Cooperative
Variceal Sclerotherapy Group study of 281 patients was stopped
prematurely because mortality was higher in the sclerotherapy group
than in the sham-treatment group (32 percent vs. 17 percent); the
rates of bleeding were 22 percent and 17 percent, respectively.
(8) The complications of sclerotherapy
included bleeding from ulcers caused by the sclerosing procedure,
dysphagia, esophageal strictures, and (rarely) perforation. (8) Given these results, nonselective
beta-adrenergic-antagonist drugs are currently the treatment of
choice for the primary prevention of bleeding from esophageal
varices in patients with cirrhosis. (5)
The above-mentioned studies were performed
before the advent of endoscopic ligation, which has replaced
injection sclerotherapy as the endoscopic method of choice for the
prevention of rebleeding (secondary prevention). In comparative
trials and in a meta-analysis of studies including 547 patients,
(9) ligation was more effective than
sclerotherapy in preventing rebleeding, in part because it resulted
in faster eradication of varices and had fewer
complications.
The logical next step was to compare
ligation of esophageal varices with drug therapy for the primary
prevention of variceal bleeding. In a trial reported in this issue
of the Journal, Sarin et al. (10) studied
patients who had varices larger than 5 mm in diameter with one or
more red signs, corresponding to the highest-risk categories.
(2,3) After 18 months, the
actuarial rate of bleeding in the ligation group was 15 percent. In
contrast, the bleeding rate in the propranolol group was 43
percent, an unusually high rate. (10) The
latter rate is similar to the 46 percent rate found by Sarin et al.
at 18 months among untreated patients in a trial of esophageal
ligation for primary prevention in patients selected according to
the same criteria and followed for a similar period of time.
(11)
The higher-than-expected rate of bleeding
in the propranolol group in the current study by Sarin et al. is
unexplained, particularly because the authors do not include
information about bleeding due to portal hypertensive gastropathy.
In addition, two other difficulties exist in interpreting the
results. First, the mean dose of propranolol, 70 mg per day, was
lower than that in previous trials, in which the mean dose was 123
mg per day (6); this low dose could in part explain the high rate
of bleeding among patients in the propranolol group. Second,
despite a significant reduction in bleeding in the ligation group
as compared with the propranolol group, there was no significant
difference between the two treatment groups either in overall
mortality or in mortality due to bleeding, in contrast to the
results of previous primary-prevention studies in which either
drugs or sclerotherapy was used. (5,6)
Should the study by Sarin et al. change
the clinical practice of giving propranolol for the primary
prevention of variceal bleeding? Though the question is arguable,
we think not, because of the difficulties in interpreting the
results, described above, and because of the similarity of the
results to those of some trials of sclerotherapy. (5) Moreover, the preliminary results of another recent
trial suggest that ligation has no advantage over
propranolol.(12)Finally, propranolol
is very cheap and safe. We think that patients with cirrhosis
should continue to be examined for varices by endoscopy and that
those with varices should be considered for primary-prevention
therapy. Patients deemed to be at high risk for bleeding should be
given a nonselective beta-adrenergic drug, and for now, ligation
should be reserved for patients who have contraindications to or
intolerance of these drugs.
Andrew K. Burroughs, F.R.C.P.
David Patch, M.R.C.P.
Royal Free Hospital
London NW3 2QG, United Kingdom
References
1. D'Amico G, Luca A. Natural history: clinical-haemodynamic
correlations: prediction of the risk of bleeding. Baillieres Clin
Gastroenterol 1997;11:243-56.
2. The North Italian Endoscopic Club for the Study and Treatment
of Esophageal Varices. Prediction of the first variceal hemorrhage
in patients with cirrhosis of the liver and esophageal varices: a
prospective multicenter study. N Engl J Med 1988;319:983-9.
3. Beppu K, Inokuchi K, Koyanagi N, et al. Prediction of
variceal hemorrhage by oesophageal endoscopy. Gastrointest Endosc 1981;27:213-8.
4. Rigo GP, Merighi A, Chahin NJ, et al. A prospective study of
the ability of three endoscopic classifications to predict
hemorrhage from esophageal varices. Gastrointest Endosc
1992;38:425-9.
5. Pagliaro L, D'Amico G, Sorensen TI, et al. Prevention of
first bleeding in cirrhosis: a meta-analysis of randomized trials
of nonsurgical treatment. Ann Intern Med 1992;117:59-70.
6. Poynard T, Cales P, Pasta L, et al.
Beta-adrenergic-antagonist drugs in the prevention of
gastrointestinal bleeding in patients with cirrhosis and esophageal
varices -- an analysis of data and prognostic factors in 589
patients from four randomized clinical trials. N Engl J Med
1991;324:1532-8.
7. Merkel C, Marin R, Enzo E, et al. Randomised trial of nadolol
alone or with isosorbide mononitrate for primary prophylaxis of
variceal bleeding in cirrhosis. Lancet 1996;348:1677-81.
8. The Veteran Affairs Cooperative Variceal Sclerotherapy Group.
Prophylactic sclerotherapy for esophageal varices in men with
alcoholic liver disease -- a randomized, single-blind, multicenter
clinical trial. N Engl J Med 1991;324:1779-84.
9. Laine L, Cook D. Endoscopic ligation compared with
sclerotherapy for treatment of esophageal variceal bleeding: a
meta-analysis. Ann Intern Med 1995;123:280-7.
10. Sarin SK, Lamba GS, Kumar M, Misra A, Murthy NS. Comparison
of endoscopic ligation and propranolol for the primary prevention
of variceal bleeding. N Engl J Med 1999;340:988-93.
11. Sarin SK, Guptan RK, Jain AK, Sundaram KR. A randomized
controlled trial of endoscopic variceal band ligation for primary
prophylaxis of variceal bleeding. Eur J Gastroenterol Hepatol
1996;8:337-42.
12. Stanley AJ, Forrest EH, Lui HF, et al. Band ligation versus
propranolol or isosorbide mononitrate in the primary prophylaxis of
variceal haemorrhage: preliminary results of a randomised
controlled trial. Gut 1998;42:Suppl 1:A19. abstract.
Copyright © 1999 by the Massachusetts
Medical Society. All rights reserved.
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