Factors influencing healing of duodenal ulcer. Control of nocturnal secretion by H2 blockade and characteristics of patients who failed to heal

What is an intractable duodenal ulcer and how should it be managed?

An intractable duodenal ulcer is an ulcer that has not healed after 8 weeks of full-dose treatment with a modern anti-ulcer drug. Such ulcers are relatively rare--perhaps five in 100 patients will have intractable duodenal ulceration. The differential diagnosis includes non-compliance as a cause of continuing ulceration, hypersecretion of gastric acid or other rare causes of ulcers in the duodenum. Investigations should include biopsy of the continuing ulceration at endoscopy, measurement of fasting plasma gastrin and routine haematology and biochemistry profiles. An intractable duodenal ulcer can be treated either by using a powerful antisecretory regimen (high doses of ranitidine or famotidine or a conventional dose of omeprazole), by changing to tripotassium dicitrato bismuthate or, in exceptional circumstances, by extremely careful surgical intervention.

Risk factors associated with refractory peptic ulcers

BACKGROUND & AIMS

The risk factors associated with refractory peptic ulcers are still undefined. The purpose of this study was to identify these factors in a multivariate context.

METHODS

Clinical and endoscopic findings as well as Helicobacter pylori status, gastric secretion analysis, serum gastrin levels, nonsteroidal anti-inflammatory drug (NSAID) use, and objective testing of aspirin use by platelet cyclooxygenase activity were studied in 60 consecutive refractory patients with peptic ulcer and 54 matched nonrefractory controls.

RESULTS

Refractory patients had a longer history of symptomatic ulcer, had an earlier onset, had more frequent relapses, and smoked more during the episode of refractoriness. H. pylori status was similar in both groups, but H. pylori eradication in a subset of refractory patients (23 of 26) was highly effective in healing these ulcers (14 of 23). Globally, NSAID-analgesic abuse (including > 1500 mg/day paracetamol) was present in 40% of refractory patients (P < 0.006). Objective testing showed that 43.7% of NSAID use was surreptitious. Multivariate logistic regression analysis identified only NSAID and analgesic abuse and the number of relapses as individually affecting refractoriness.

CONCLUSIONS

NSAID and analgesic abuse is the single most important exogenous factor associated with refractoriness. H. pylori infection emerges as an important intrinsic factor, but almost a quarter of refractory patients cannot be linked to either NSAID use or H. pylori infection.

Prescribing policy for antiulcer treatment in the elderly

In the short and long term treatment of peptic ulcer in the elderly some problems have yet to be resolved, mainly concerning the physiology and pathophysiology of the aging stomach, the pharmacokinetic and pharmacodynamic properties of antiulcer drugs, and the presence of different risk factors compared with young patients. The available data from controlled trials of peptic ulcer in the general population and from the limited experience in geriatrics, show that the clinical efficacy and tolerability of the anti-secretory drugs (e.g. cimetidine, ranitidine and famotidine) and of cytoprotective compounds are similar to that observed in younger patients. However, more data are necessary concerning the optimal dosage in relation to physiological age-related changes of liver and kidney function, the duration of prophylactic treatment, and importantly, the assurance of adequate patient compliance.

Why do ulcers heal with sucralfate?

It is unknown why ulcers in general heal. Some clues are worth considering. What is known is (i) that ulcer healing occurs spontaneously, (ii) that ulcers heal more quickly in the duodenum than in the stomach, (iii) that mucosal blood flow at ulcer edge improves with healing, and (iv) that healing can be speeded up by (a) not smoking, (b) removing acid from the stomach, and (c) using non-antisecretory mucosal protective agents such as sucralfate and colloidal bismuth. The difference in healing rates between duodenal and gastric ulcers may be related to ulcer size, duodenal alkalinity due to the secretion of the Brunner's glands, and other uninvestigated factors such as epidermal growth factor and mucosal blood flow. The difference between smokers and non-smokers may be related to inhibition of prostaglandin synthesis and impairment of mucosal blood flow due to smoking and to higher acid secretion in smokers. The success with antisecretory agents indicates that acid inhibits the healing process. The success of sucralfate and bismuth indicates that cytoprotective mechanisms play a role in ulcer healing. The literature also shows that ulcer healing is less affected by smoking in patients treated with sucralfate than in those treated with antisecretory agents, suggesting that cytoprotective mechanisms play a more important part than acid inhibition in counteracting the adverse effects of smoking on healing. Furthermore, ulcer relapse occurs sooner in patients treated with antisecretory agents than in those treated with sucralfate or bismuth, suggesting that withdrawal of antisecretory agents speeds up relapse and/or that cytoprotective mechanisms are associated with longer-lasting remission. It is concluded that sucralfate healing involves cytoprotective mechanisms and that these cannot be ignored in the planning of any anti-ulcer therapy. Despite the understanding of the various site-protective and cytoprotective mechanisms, as discussed in the previous article, it is not clear why ulcers heal with sucralfate. In fact, there is no clear answer to the fundamental question as to why ulcers in general heal with the known therapeutic agents, including H2-receptor antagonists, antacids, proton pump inhibitors, anticholinergics, site-protective agents, and cytoprotective agents. This review examines this question, using sucralfate as a model.

Arbaprostil [15(R)-15-methyl prostaglandin E2] in a single nighttime dose of either 50 or 100 micrograms in acute duodenal ulcer

To determine the efficacy of single nighttime doses of arbaprostil [15(R)-15-methyl prostaglandin E2], 50 or 100 micrograms for 4 wk, a double-blind randomized placebo-controlled multiclinic trial was undertaken. Success was defined as complete healing of the ulcer documented by endoscopy. Fifty-one of 64 patients enrolled were considered evaluable. Ulcer healing was documented in 64.3%, 85.7%, and 31.2% of the 100-micrograms arbaprostil, 50-micrograms arbaprostil, and placebo treatment groups (p value vs. placebo = 0.003 and 0.002, respectively). No difference in side effects or changes in laboratory parameters were found between the treatment groups except that diarrhea, usually mild, was found more often in the 100-micrograms arbaprostil group (60.0%) than in the 50-micrograms arbaprostil (31.8%) or placebo groups (23.5%) (p value 100 micrograms arbaprostil vs. placebo = 0.02). A single nighttime administration of arbaprostil seems to be a safe and efficacious agent for the treatment of acute duodenal ulcer.

Natural history of Campylobacter pylori in duodenal ulceration treated with an H2-antagonist

Campylobacter pylori has been associated closely with active antral gastritis and duodenal ulcer but its pathogenetic role remains uncertain. The present longitudinal study examined, prospectively, the endoscopic antral biopsies of 45 patients with duodenal ulceration, taken before and after healing of the duodenal ulcer, during remission and at relapse. The biopsies were examined for the activity and degree of chronic inflammation of the gastritis and for the occurrence and density of C. pylori by Warthin-Starry stain. Before treatment the frequency of chronic active antral gastritis was 100% and the occurrence of C. pylori was 97%. Compared with the pre-treatment state, there was no significant change in either the frequency and severity of antral gastritis, or in the occurrence and density of the bacteria in the antral mucosa at the time the duodenal ulcer healed, during remission, or at relapse. The occurrence of the bacteria was significantly more frequent during remission, than at the time when the ulcer had healed initially (P less than 0.05). These results suggest that the bacterium may not play an important pathogenetic role in ulcer healing and relapse, when patients are managed using an H2-blocker.

A randomized study of maintenance therapy with ranitidine to prevent the recurrence of duodenal ulcer

After an active duodenal ulcer has healed in response to medical therapy, the rate of recurrence during the subsequent year is relatively high. We therefore enrolled 140 patients with healed duodenal ulcers in a two-year randomized, double-blind trial comparing maintenance therapy (ranitidine, 150 mg nightly) with placebo for the prevention of recurrent duodenal ulceration. We performed endoscopy annually and when symptoms suggested the recurrence of ulcers. Verified recurrent ulcers in either group were treated for four or eight weeks with open-label ranitidine (150 mg twice a day). Patients whose ulcers healed within eight weeks resumed randomized treatment. Prophylactic therapy with ranitidine reduced the rate of ulcer relapses from 63 percent in the placebo group to 37 percent in the ranitidine group (P less than 0.05). Treatment with ranitidine extended the median ulcer-free interval from one to two years (P less than 0.05). The first recurrences of ulcer were asymptomatic in half the ranitidine group and in a quarter of the placebo group. Prophylactic therapy with ranitidine also reduced the frequency of recurrent ulcers that were unhealed by eight weeks, that were bleeding, that were in the stomach, or that were the second recurrent ulcer within six months, from 43 percent in the placebo group to 21 percent. Patients who drank alcohol, smoked, had a history of ulcer disease, or had duodenal scarring or erosion at the time of entry into the study were at the greatest risk for recurrence and benefited the most from prophylactic ranitidine. We conclude that prophylactic treatment with ranitidine is effective in preventing the recurrence of duodenal ulceration.

Refractory duodenal ulcers (nonhealing duodenal ulcers with standard doses of antisecretory medication)

To evaluate possible differences between patients with refractory duodenal ulcers and those with duodenal ulcers that respond to standard doses of antisecretory medications, we determined basal acid outputs by nasogastric suction and daily smoking histories in 75 patients with endoscopically documented active duodenal ulcers. Patients were treated for at least eight weeks with standard doses of antisecretory medications and endoscopic healing or nonhealing was documented. Fifty-five patients that had complete healing of their duodenal ulcers had a mean basal acid output of 6.6 +/- 5.3 meq/hr, and 18/55 had daily cigarette smoking histories, whereas 20 patients that had nonhealing duodenal ulcers had a mean basal acid output of 20.0 +/- 9.6 meq/hr, and 8/20 had daily cigarette smoking histories. There were no significant differences between the two groups with regard to age, duodenal ulcer size, or cigarette smoking history. However, there were significant differences in male-female ratio (P less than 0.02) and in mean basal acid output (P less than 0.001), and all patients with nonhealing duodenal ulcers had basal acid outputs of greater than 10.0 meq/hr. Patients with nonhealing duodenal ulcers were treated with increased doses of ranitidine, mean 675 mg/day (range 600-1200 mg/day), and all had complete healing endoscopically documented. These results indicate that patients treated with standard doses of antisecretory medications with nonhealing duodenal ulcers have increased basal acid outputs of greater than 10.0 meq/hr, and the duodenal ulcers heal with increased doses of antisecretory medication.

Oxmetidine (H2 receptor antagonist) induced cytotoxicity in isolated rat hepatocytes

Oxmetidine, a new and more potent analogue of the H2 receptor antagonist, cimetidine, was recently withdrawn from clinical trials because of associated hepatotoxicity. We investigated the potential hepatotoxicity of the drug in vitro and in vivo in the rat. In addition, we investigated, in in vitro experiments, the potential hepatoxicity of other gastric acid inhibitory drugs (cimetidine, ranitidine, omeprazole and nolinium bromide). In in vitro experiments, oxmetidine, at various concentrations, was added to isolated hepatocyte incubations and cytotoxicity was assayed by trypan blue exclusion. In in vivo experiments, oxmetidine was administered both i.p. and orally, and hepatotoxicity was assessed by serum biochemical measures (transaminases, alkaline phosphatase, 5' nucleotidase, gamma glutamyl transpeptidase) and liver histopathology. In the in vitro studies, the addition of oxmetidine to the hepatocyte incubations was associated with significant (P less than 0.001) dose and time dependent cytotoxicity. However, the in vivo experiments revealed no significant changes in serum biochemistry and no significant alterations in liver histopathology up to 72 h following the administration three different dosages of oxmetidine. Of the other gastric acid inhibitory drugs, only nolinium bromide was associated with significant (P less than 0.001) in vitro cytotoxicity. Our in vitro observations establish that oxmetidine is cytotoxic to isolated rat hepatocytes and suggest that nolinium bromide be further evaluated for potential hepatotoxicity.

Multiple duodenal ulcer: natural history and pathophysiology

It has not been established whether multiple duodenal ulcer is associated with a different natural history, pathophysiology, and therapeutic response than a single duodenal ulcer. A consecutive series of 96 patients with two or more duodenal ulcers at endoscopy, representing 9.6% of the total number of new patients with duodenal ulcer seen during the period 1980-1985, were compared with a random series of 200 patients with single duodenal ulcer seen in the middle years of this period. Multiple duodenal ulcer was associated with higher (p less than 0.02) male to female ratio, more (p less than 0.05) late onset patients (those with ulcer symptoms starting after age 30 years, more (p less than 0.05) chronic cigarette smokers, and more frequent (p less than 0.05) moderate to severe deformity of the duodenal bulb. More (p less than 0.05) patients with multiple duodenal ulcer had abnormally low D50 derived from pentagastrin dose response tests, indicating that they were more sensitive to gastrin stimulation. Furthermore, their mean fasting and meal stimulated serum gastrin concentrations were significantly higher than those of patients with single ulcer (p less than 0.005), or of controls (p less than 0.05). Compared with single duodenal ulcer, multiple ulcer had significantly lower placebo healing rate, and required a higher dose of misoprostol (1200 v 800 micrograms/day) to achieve a similar healing efficacy at four weeks. We conclude that multiple duodenal ulcer is associated with different clinical features, pathophysiology, and possibly therapeutic response from single duodenal ulcer, and appears to represent the more aggressive side of the ulcer spectrum.

Large single daily dose of histamine H2 receptor antagonist for duodenal ulcer. How much and when? A clinical pharmacological study

The effects of single doses of cimetidine 800, 1200, and 1600 mg, given at 2300 h or 800, and 1600 mg at 1800 h, have been studied in patients with duodenal ulcer disease in symptomatic remission, and compared with cimetidine 400 mg bd (0800 h and 2300 h) and ranitidine 300 mg (given at 1800 h) respectively. A dose related reduction in intragastric acidity was seen. All single nocturnal (2300 h) doses of cimetidine produced anacidity overnight. This was not achieved with dosing at 1800 h although the duration of inhibition of gastric acidity was longer. Inhibition of overnight acid and pepsin outputs were similarly dose and timing related, but inhibition of peptic activity was much less after dosing at 1800 h. Cimetidine 1600 mg and ranitidine 300 mg were similar in their effects.

Nizatidine as maintenance therapy of duodenal ulcer disease in remission

A new H2-receptor antagonist, nizatidine (150 mg h.s.), was compared with placebo as maintenance therapy in a randomized, parallel, double-blind, one-year study of 513 patients with recently healed duodenal ulcer. Endoscopies were performed at 0, 3, 6, and 12 months and at unscheduled times if symptoms of active peptic ulcer disease were present. Cumulative ulcer recurrence rates for nizatidine and placebo were 13 versus 40% at 3 months, 24 versus 57% at 6 months, and 34 versus 64% at 12 months. The differences were significant (p less than 0.001) at each treatment period. Smokers in both treatment groups had significantly greater recurrence rates than non-smokers. Symptoms of peptic ulcer disease were significantly less in nizatidine-treated patients in the first 3 months of treatment. Adverse events, including those related to peptic ulcer disease, occurred more frequently in placebo-treated patients. Nizatidine proved to be safe and effective in preventing recurrences of duodenal ulcer.

Cigarette smoking delays gastric emptying of a radiolabelled solid food in healthy smokers

The effect of cigarette smoking on gastric emptying was studied in 18 healthy volunteers by means of an isotopic method. Although the observed individual reactions were fairly variable, cigarette smoking significantly delayed gastric emptying of a solid meal. Potential mechanisms of action of cigarette smoking on gastric emptying are discussed, including the role of nicotine. The method of gastric emptying measurement was shown to be reproducible in the paired studies performed in 11 subjects.

Chronic antral gastritis in duodenal ulcer. Natural history and treatment with prostaglandin E1

The natural history of chronic antral gastritis in relation to the healing of duodenal ulcer and its response to treatment, if any, are unknown. We performed a double-blind controlled trial using an oral prostaglandin E1, misoprostol, in 229 patients with active duodenal ulcer randomized to receive placebo (n = 76), misoprostol 200 micrograms (n = 77), or misoprostol 300 micrograms (n = 76), q.i.d. orally. Healing of duodenal ulcer was assessed biweekly up to 12 wk by endoscopy, during which procedures at least two antral and two fundal biopsy specimens were taken. The activity and the degree of chronic inflammation of gastritis, as assessed histologically by the infiltration of polymorphs and chronic inflammatory cells, respectively, was graded blindly by two pathologists as nil, mild, moderate, or severe. Before treatment, 99% of patients had chronic antral gastritis and 1.5% had chronic fundal gastritis. In the placebo group, healed duodenal ulcer was associated with significantly (p less than 0.01, life table analysis) higher incidence of improvement of the activity of the antral gastritis (nil or mild as endpoint) than unhealed ulcer (30% vs. 4% at week 8). Irrespective of whether duodenal ulcer was healed or unhealed, significantly (p less than 0.01) more patients on misoprostol (50% at week 8) showed improvement (nil or mild as endpoint) than the placebo group. The degree of chronic inflammation of the antral gastritis showed similar significant changes in favor of misoprostol. Smoking and alcohol intake had no significant effect on the improvement of chronic antral gastritis. In conclusion, healing of duodenal ulcer was associated with improvement of the activity of chronic antral gastritis, which, as shown for the first time, could be further enhanced by a therapeutic agent--prostaglandin E1.

Comparison of enprostil and cimetidine in active duodenal ulcer disease. Summary of pooled European studies

Data were combined for statistical analysis from four European trials comparing enprostil (35 micrograms twice daily) with cimetidine (400 mg twice daily) in the treatment of duodenal ulcer, using a double-blind, randomized design with endoscopic control. A total of 369 patients entered the trials, of whom 348 were eligible for the efficacy analyses and 362 for the safety analyses. Patients were allowed antacids as needed. The pooled cumulative healing rates at two, four, and six weeks were 40, 75, and 84 percent, respectively, for enprostil and 42, 77, and 87 percent, respectively, for cimetidine. There were no significant differences between treatments. Healing rates in both groups were reduced in smokers, in those with larger ulcers at baseline, and in those who reported a higher consumption of alcohol. Age, however, had no effect on healing rates. Digestive system complaints were reported more frequently in the enprostil group, whereas central nervous system complaints were more than twice as frequent in the cimetidine group.

Prostaglandin E1 (misoprostol) overcomes the adverse effect of chronic cigarette smoking on duodenal ulcer healing

Chronic cigarette smoking adversely affects duodenal ulcer healing despite treatment by potent gastric acid-reducing agents. Prostaglandins of the E series possess antisecretory and cytoprotective properties and theoretically offer advantages over existing therapeutic agents. A double-blind randomized study was performed to compare complete duodenal ulcer healing as assessed by endoscopies every two weeks for up to 12 weeks. Two hundred twenty-nine patients were randomized to receive misoprostol, an orally stable synthetic derivative of prostaglandin E1, in 200-micrograms or 300-micrograms qid dosages, or placebo. Life-table analysis showed that (1) both regimens of misoprostol were significantly more effective than placebo, achieving healing rates of 61% and 71%, respectively, at four weeks, and (2) cigarette smoking significantly impaired healing by placebo but not by misoprostol. In fact, the time-healing curves of smokers and nonsmokers on the higher dose of misoprostol completely overlapped. Furthermore, delayed treatment and large ulcer diameter adversely affected healing by misoprostol in smokers, whereas in nonsmokers, high basal and maximal acid output were unfavorable. Misoprostol is recommended for the treatment of duodenal ulcer, particularly in chronic smokers early in a given period of symptoms.