Potential hazards of long-term acid suppression

Intravenous pantoprazole utilization in a level 1 trauma center

BACKGROUND

In recent years there has been a rapid increase in the use of proton pump inhibitors. Our institution has recently had several shortages of IV pantoprazole, each lasting 7-10 days. The purpose of our study was to evaluate in-patient usage of IV pantoprazole. We hypothesized that hospitalized patients with upper gastrointestinal bleeding (GIB) or risk for stress ulcers inappropriately received IV pantoprazole based on current literature.

METHODS

This was a retrospective study of 165 consecutive in-patients identified as receiving pantoprazole from December 2004 to March 2005. Only patients receiving IV pantoprazole were included (n = 78). Data collected included demographics, indication and dosing of pantoprazole, admitting team (surgery vs. medicine), and risk factors for stress ulcers.

RESULTS

Our study population had a mean age of 54 +/- 17 years and 62% were male. Overall, 45% (35/78) of patients receiving IV pantoprazole had an appropriate indication, and 19% (15/78) received the correct dose. Of the 78 patients, 43 (55%) were treated with pantoprazole for stress ulcer prophylaxis (SUP), and 35 (45%) patients were treated for GIB. We found that none of the 43 patients treated for SUP had an appropriate indication for pantoprazole, but all of the patients with GIB (35) had an appropriate indication. Of the 35 patients treated for GIB with pantoprazole, only 40% (14/35) received the correct dose. In all cases of incorrect dosing, the patients were underdosed.

CONCLUSIONS

Pantoprazole is not being prescribed appropriately for stress ulcer prophylaxis in our patient population. Even in patients appropriately receiving pantoprazole the majority were prescribed an incorrect dose. Appropriate indications and dosing of pantoprazole could eliminate the shortages seen at our institution.

Intragastric volatile N-nitrosamines, nitrite, pH, and Helicobacter pylori during long-term treatment with omeprazole

BACKGROUND & AIMS

This study evaluated the effect of long-term gastric acid suppressive therapy with omeprazole on intragastric levels of carcinogenic N-nitrosamines and related parameters.

METHODS

Forty-five patients on long-term omeprazole medication (mean, 35 months) and 13 healthy subjects without medication participated. Volatile N-nitrosamines were determined in gastric juice and urine. Intragastric pH, nitrite, nitrate, and H. pylori status were determined. DNA isolated from gastric biopsy specimens was analyzed for precarcinogenic alkyl-DNA adducts.

RESULTS

The intragastric pH in patients was significantly higher compared with controls (P = 0.0001). Gastric nitrite levels in patients were nonsignificantly higher. There was no difference in total levels of intragastric volatile N-nitrosamines between patients and controls, however, urinary N-nitrosodimethylamine excretion was higher in patients (P = 0.001). On omeprazole, Helicobacter pylori-positive vs. -negative patients had a nonsignificantly higher intragastric nitrite level and higher urinary N-nitrosodimethylamine excretion. No alkyl-DNA adducts could be detected in gastric epithelium.

CONCLUSIONS

Increased intragastric pH caused by long-term treatment with omeprazole does not result in increased intragastric levels of nitrite and volatile N-nitrosamines. The significantly higher urinary N-nitrosamine excretion implies the risk of increased endogenous formation of N-nitrosamines during long-term omeprazole treatment. This risk may be higher in H. pylori-positive patients.

Overuse of proton pump inhibitors

BACKGROUND

There have been concerns raised about the potential adverse effects of proton pump inhibitors, especially with long-term use. In particular, their potent action can suppress the features and delay the diagnosis of gastric cancer, while prolonged exposure may hasten the development of gastric carcinoids.

AIM

To examine the use of proton pump inhibitors in patients at the major teaching hospital in Tasmania, Australia, principally to determine the appropriateness of the therapy according to published guidelines.

METHODS

A retrospective review of the medical records of all patients prescribed any of the proton pump inhibitors at the hospital over a 7-month period, was performed. An extensive range of demographic and clinical variables was recorded for each patient. The patients were also asked a series of questions during their hospitalization to extract some of the relevant information - in particular, if and when they had undergone endoscopy.

RESULTS

The 200 patients (52% males) had a mean age of 69 +/- 16.4 years. The most common indications for using proton pump inhibitors were acute gastrointestinal bleeding (20.9%), severe refractory ulcerating oesophagitis (17.3%), mild/moderate oesophageal reflux (17.3%) and refractory peptic ulcer (11.7%). A large number of patients were using a proton pump inhibitor for 'other' indications (39.6%). The prescribing of proton pump inhibitors satisfied the approved indications, as outlined in the Australian Schedule of Pharmaceutical Benefits, in only 37.1% of cases. Endoscopy had been performed in 54.1% of patients prior to commencing therapy with a proton pump inhibitor and within the next 7 days in another 12.8% of patients. Only 59% of patients had previously been treated with an H2-receptor antagonist before commencing therapy with a proton pump inhibitor. Even worse, only 58.5% of patients had used an H2-receptor antagonist before a proton pump inhibitor for mild/moderate oesophagitis. The median duration of proton pump inhibitor therapy for patients admitted to the hospital and already receiving one of the drugs was 450 days. Over half of the patients were being concurrently treated with other drugs which are known to cause or exacerbate gastro-oesophageal disease, and 18% were smokers.

CONCLUSION

Whereas the proton pump inhibitors are undoubtedly effective agents, studies of their prescribing in practice consistently suggest over-use prior to endoscopy, use in patients who do not fit the approved criteria, and prescribing for indications in which 'less powerful' agents should have been sufficiently effective for the patient's symptoms. This poses economic and safety concerns, particularly in light of the suggestion that these drugs could delay the diagnosis of gastric cancer.