Gastrointestinal complications of nonsteroidal anti-inflammatory drugs: prophylactic and therapeutic strategies

Analysis of risk factors for colonic diverticular bleeding and recurrence

The increase in incidence of colonic diverticular bleeding is relative to an age-related rise in the incidence of colonic diverticulosis and use of antithrombotic medication. However, risk factors related to the onset, recurrence, and prophylaxis have not been established. Therefore, we aimed to determine risk factors for the onset and recurrence of colonic diverticular bleeding.An age- and sex-matched case-control study was performed to assess the risk factors for the onset of colonic diverticular bleeding. The distribution of diverticulosis, comorbidity, and medication were evaluated from medical records. We also assigned patients with a first-time bleeding into groups with and without rebleeding during follow-up to determine risk factors for recurrence.Bilateral colonic diverticulosis, nonselective nonsteroidal anti-inflammatory drugs (NSAIDs), low-dose aspirin (LDA), and anticoagulants were significant risk factors for the onset of colonic diverticular bleeding on multivariate analysis. In contrast, the use of selective cyclooxygenase-2 (COX-2) inhibitor was not a risk factor for the onset. The incidence of bleeding in direct oral anticoagulant and warfarin users was not different between the 2 groups. The cumulative recurrence rate at 1 year was 15%. Recurrence rate was significantly higher in patients with a prior history of colonic diverticular bleeding than those without. Steroid use was associated with recurrence.Extensive distribution of diverticulosis and use of nonselective NSAIDs, LDA, and anticoagulants are regarded as risk factors for the onset of colonic diverticular bleeding. In addition, a prior history of colonic diverticular bleeding is related to the recurrence.

The electroacupuncture-induced analgesic effect mediated by 5-HT1, 5-HT3 receptor and muscarinic cholinergic receptors in rat model of collagenase-induced osteoarthritis

BACKGROUND

Osteoarthritis (OA) is an degenerative disease characterized by chronic joint pain. Complementary and alternative treatment such as acupuncture have been utilized to alleviate pain. The objective of this study was to investigate the analgesic mechanisms of electroacupuncture (EA) in the collagenase-induced osteoarthritis (CIOA) rat model.

METHODS

Four weeks after inducing CIOA by injecting collagenase solution into the left knee of 5-week-old male Sprague-Dawley rats, 2 Hz and 100 Hz EA on Zusanli (ST 36) was performed. The analgesic effect of EA was evaluated by the tail flick latency (TFL) and paw pressure threshold (PPT) tests. To investigate the analgesic mechanism, serotonergic and muscarinic cholinergic receptor agonists and antagonists were injected 20 min prior to EA and the resultant changes were evaluated by the TFL and PPT tests.

RESULTS

EA on Zusanli (ST 36) demonstrated an analgesic effect in the CIOA rat model. The 2 Hz EA treatment showed a significantly greater analgesic effect than the 100 Hz treatment. The analgesic effect of 2 Hz EA was not strengthened by 5-HT1, 5-HT2, 5-HT3, and muscarinic cholinergic receptor agonist pretreatment, was blocked by 5-HT1, 5-HT3, and muscarinic cholinergic receptor antagonist pretreatment, but not blocked by 5-HT2 receptor antagonist pretreatment.

CONCLUSIONS

In the CIOA rat model, EA on Zusanli (ST 36) exhibited analgesic effects, and 2 Hz EA resulted in a significantly greater analgesic effect than 100 Hz EA. The analgesic effect of 2 Hz EA was reduced by pretreatment of 5-HT1 receptor, 5-HT3 receptor and muscarinic cholinergic receptor antagonists.

Design, synthesis, molecular modeling and biological evaluation of novel diaryl heterocyclic analogs as potential selective cyclooxygenase-2 (COX-2) inhibitors

New series of 3,4-diaryl-2-thioxoimidazolidin-4-ones and 3-alkylthio-4,5-diaryl-4H-1,2,4-triazoles were designed, synthesized and evaluated for their activity as anti-inflammatory agents. Compounds 20, 21, 23 and 34 are highly selective inhibitors of COX-2 enzyme at a concentration of 100 mM relative to celecoxib, the standard reference. (±)-3-(4-Phenoxy-phenyl)-5-phenyl-2-thioxoimidazolidin-4-ones 23 exhibited the most active anti-inflammatory agent.

Postoperative complications in a lamb after major surgery

INTRODUCTION

Anaesthesia in lambs undergoing experimental surgery may develop problems associated with age-related immune incompetency: a postoperative complication in a 3 week old Scottish blackface lamb after spinal surgery is presented. CASE HISTORY AND MANAGEMENT: Both lamb and ewe were in good condition. The ewe was vaccinated against Clostridium perfringens and Clostridium tetani 5 weeks pre-partum. There were no apparent problems with the lamb's intake of colostrum. Pre-anaesthetic medication was intramuscular medetomidine (10 μg kg(-1)). Anaesthesia was induced and maintained with sevoflurane in oxygen. Morphine (0.5 mg kg(-1)), meloxicam (0.6 mg kg(-1)) and ketamine (1 mg kg(-1) followed by 10 μg kg(-1) minute(-1)) were administered intravenously (IV) for perioperative analgesia. Atracurium (0.5 mg kg(-1) IV, followed by 0.17 mg kg(-1) injected when the first twitch of the four, train-of four count was palpated) was used to improve muscle relaxation. The lamb's trachea was intubated and the lungs mechanically ventilated to maintain normocapnia. Intrathecal morphine (0.2 mg kg(-1)), IV meloxicam (0.3 mg kg(-1)) and edrophonium (0.5 mg kg(-1)) were administered before recovery. Operative and initial recovery periods were unremarkable. Three hours after surgery the lamb became depressed. Tachycardia (180-250 beats minute(-1)), tachypnoea (30 breaths minute(-1)), poor peripheral perfusion and cold pelvic limb extremities were present mimicking severe pain, and/or hypovolaemic shock. Analgesics - morphine (total dose 1.3 mg kg(-1)) - and IV fluid therapy boluses - crystalloids (300 mL), colloids (120 mL) and fresh whole blood (60 mL) - failed to ameliorate clinical signs and so the lamb was euthanized 10 hours after surgery. Post-mortem findings supported a possible diagnosis of peracute Clostridium perfringens enterotoxaemia.

CONCLUSION

Clostridium perfringens enterotoxaemia should be considered when clinical signs of severe pain and/or hypovolaemic shock fail to respond to analgesics and fluid resuscitation in lambs after major surgery.

Guidelines for prevention of NSAID-related ulcer complications

Guidelines for clinical practice are intended to indicate preferred approaches to medical problems as established by scientifically valid research. Double-blind, placebo-controlled studies are preferable, but compassionate use reports and expert review articles are used in a thorough review of the literature conducted through Medline with the National Library of Medicine. Only when data that will not withstand objective scrutiny are available is a recommendation identified as a consensus of experts. Guidelines are applicable to all physicians who address the subject, without regard to specialty training or interests, and are intended to indicate the preferable, but not necessarily the only, acceptable approach to a specific problem. Guidelines are intended to be flexible and must be distinguished from standards of care, which are inflexible and rarely violated. Given the wide range of specifics in any health-care problem, the physician must always choose the course best suited to the individual patient and the variables in existence at the moment of decision. These guidelines were developed under the auspices of the American College of Gastroenterology by a committee of experts in the field, reviewed by its Practice Parameters Committee, and approved by the Board of Trustees. The recommendations of these guidelines are therefore considered valid at the time of production based on the data available. New developments in medical research and practice pertinent to each guideline will be reviewed at an established time and indicated at publication to assure continued validity. Owing to the volume of new data on the subject of non-steroidal anti-inflammatory drug (NSAID)-related injury to the upper gastrointestinal tract, i.e., the advent of cyclooxygenase (COX)-2 inhibitors, new data on interactions between these agents, as well as traditional NSAIDs, with aspirin and H. pylori, it was elected by the Committee to confine these guidelines to upper gastrointestinal (GI) injury and to leave post-duodenal injury as the subject of a separate guideline.

Effects of Aloe vera and sucralfate on gastric microcirculatory changes, cytokine levels and gastric ulcer healing in rats

AIM: To compare the effects of Aloe vera and sucralfate on gastric microcirculatory changes, cytokine levels and gastric ulcer healing.

METHODS: Male Spraque-Dawley rats (n= 48) were divided into four groups. Group1 served as control group, group 2 as gastric ulcer group without treatment, groups 3 and 4 as gastric ulcer treatment groups with sucralfate and Aloe vera. The rats from each group were divided into 2 subgroups for study of leukocyte adherence, TNF-α and IL-10 levels and gastric ulcer healing on days 1 and 8 after induction of gastric ulcer by 20 % acetic acid.

RESULTS: On day 1 after induction of gastric ulcer, the leukocyte adherence in postcapillary venule was significantly (P< 0.05) increased in the ulcer groups when compared to the control group. The level of TNF-α was elevated and the level of IL-10 was reduced. In the ulcer groups treated with sucralfate and Aloe vera, leukocyte adherence was reduced in postcapillary venule. The level of IL-10 was elevated, but the level of TNF-α had no significant difference. On day 8, the leukocyte adherence in postcapillary venule and the level of TNF-α were still increased and the level of IL-10 was reduced in the ulcer group without treatment. The ulcer treated with sucralfate and Aloe vera had lower leukocyte adherence in postcapillary venule and TNF-α level. The level of IL-10 was still elevated compared to the ulcer group without treatment. Furthermore, histopathological examination of stomach on days 1 and 8 after induction of gastric ulcer showed that gastric tissue was damaged with inflammation. In the ulcer groups treated with sucralfate and Aloe vera on days 1 and 8, gastric inflammation was reduced, epithelial cell proliferation was enhanced and gastric glands became elongated. The ulcer sizes were also reduced compared to the ulcer group without treatment.

CONCLUSION: Administration of 20 % acetic acid can induce gastric inflammation, increase leukocyte adherence in postcapillary venule and TNF-α level and reduce IL-10 level. Aloe vera treatment can reduce leukocyte adherence and TNF-α level, elevate IL-10 level and promote gastric ulcer healing.

The use of celecoxib for reduction of pain after subpectoral breast augmentation

A study was conducted to determine whether a single 400-mg dose of oral celecoxib administered 30 min before surgery reduces the opioid requirement for patients undergoing aesthetic subpectoral breast augmentation. A total of 695 patients undergoing breast augmentation were randomly selected into either a placebo or a treatment group. The findings showed that patients who received 400 mg of celecoxib 30 min before surgery required significantly fewer opioid analgesics after the operation than those given a placebo (p < 0.001). It also was found that nonsmokers and multiparous women required significantly fewer opioids than smokers and nulliparous women (p < 0.001). On the basis of this prospective study, the authors recommend a single 400-mg dose of celecoxib administered 30 min before surgery to decrease opioid analgesic requirements after subpectoral breast augmentation.

The effect of Aloe vera A. Berger (Liliaceae) on gastric acid secretion and acute gastric mucosal injury in rats

The effect of varying doses of ethanol extract of Aloe vera (Liliaceae) on acute gastric mucosal lesions induced by 0.6 M HCl and acid output was studied in the pylorus ligated and lumen perfuse rats, respectively. Acid secretion was determined by titration of the collected gastric juice to pH 7.0. Intraperitoneal injection of Aloe vera, dose dependently inhibited gastric acid secretion. The plant was more active as a gastroprotective agent at lower concentration against mucosal injury induced by 0.6 M HCl. In conclusion, Aloe vera is endowed with gastric acid anti-secretory activity and could protect the gastric mucosa at low concentrations against injurious agents.

Traitements curatif et préventif des ulcères gastro-duodénaux induits par les AINS

The use of treatments to heal or to prevent nonsteroidal anti-inflammatory drugs (NSAIDs) associated gastroduodenal lesions is based on replacement of mucosal prostaglandin deficiency or inhibition of acid secretion. Four-week acid suppression by proton pump inhibitors (PPI) with 7-day eradication triple therapy in Helicobacter pylori positive patients is effective in healing gastric and duodenal ulcer upon discontinuation of NSAIDs. In the event NSAIDs must be continued, PPIs (omeprazole 20 mg, lansoprazole 30 mg, pantoprazole 40 mg) are more effective than H2-blockers and cytoprotective agents (sucralfate, misoprostol) to heal mucosal lesions. In long-term prevention studies, omeprazole 20 mg, lansoprazole 15 mg, and pantoprazole 20 mg significantly reduce gastric and duodenal ulcer rates. Misoprostol 800 microg is as effective as PPIs for preventing symptomatic and complicated gastric ulcers, but less effective to prevent duodenal ulcer, with a high rate of adverse effects such as diarrhea. Helicobacter pylori eradication in infected patients decrease the risk of NSAIDs-associated lesions but is less effective than concomitant antisecretory treatment. Current data from comparative studies of PPIs vs ranitidine or misoprostol are in favor of the PPIs as well tolerated and effective drugs in the prophylaxis of NSAIDs-related gastroduodenal lesions in high-risk patients.

Sucralfate therapy in NSAID bleeding gastropathy

BACKGROUND AND AIMS

A randomized, double-blind, placebo-controlled, multicenter study was conducted to assess the efficacy of 2 g sucralfate suspension in treating gastric mucosal lesions caused by long-term treatment with nonsteroidal anti-inflammatory drugs (NSAIDs).

METHODS

Only patients given NSAIDs continuously for at least 2 months with positive fecal occult blood (FOB) and endoscopically confirmed mild to moderate mucosal lesions (Lanza scale, grades 2-4) were included. After 1-week run-in phase, patients were stratified into 2 groups according to gastropathy-related symptoms during the preceding 7 days (symptomatic vs. asymptomatic) and randomized to 2 g (10 mL) of sucralfate suspension or placebo twice a day over a 6-week period. NSAIDs were given according to each patient's dosage schedule and always after meals.

RESULTS

Twenty-five patients received sucralfate and 25 received placebo. At the end of the study, 68% (17/25) of patients given sucralfate had no lesions (Lanza grade 0) on endoscopy compared with 35% (8/23) in controls (P = 0.042). The Lanza grades in patients given sucralfate were significantly improved compared with the placebo patients (P = 0.022).

CONCLUSIONS

In this target population selected according to positive FOB test and endoscopic evidence of mucosal injury, chronic administration of sucralfate significantly decreased NSAID-induced gastric erosions.

COX-2 inhibitors. Are they nonsteroidal anti-inflammatory drugs with a better safety profile?

In the treatment of arthritis, NSAIDs are some of the most commonly used drugs, although the prescription of such drugs has been questioned due to their inherent risks for gastrointestinal compromise, platelet effects, and the potential for renal toxicity with long-term use. With the availability of celecoxib and rofecoxib, 2 cyclooxygenase (COX-2) inhibitors (or COX-1 sparing agents) as new forms of NSAIDs, these issues have become magnified not only in the context of risk-to-benefit ratios but also interms of pharmacoeconomics because they have been proven to be equally efficacious as the nonselective NSAIDs, with an improved safety profile particularly within the gastrointestinal tract, but at a significantly increased cost.

Anti-inflammatory drugs: new multitarget compounds to face an old problem. The dual inhibition concept

In this short review we have tried to focus on some new relevant aspects of the pharmacological control of inflammation. The clinical availability of new drugs able to produce a selective inhibition of type 2 cyclooxygenase (COX-2), the enzyme thought to be mainly responsible for generating arachidonic-acid-derived inflammatory mediators, has been the origin of much hope. However, expectations of having an effective and completely safe non-steroidal anti-inflammatory drug (NSAID) have been only partially fulfilled. Emerging information has challenged some aspects of the original hypothesis indicating COX-2 as devoid of 'housekeeping' physiological functions. Moreover, the recently available clinical studies have indicated only a relatively small improvement in the tolerability of the newer 'selective' COX-2 inhibitors over the classical COX-1/COX-2 mixed type NSAIDs. The new appreciation of the role of other arachidonic acid derivatives, the leukotrienes (LTS), in producing and maintaining inflammation has generated considerable interest in drugs able to block LTS receptors or to produce a selective inhibition of 5-lipoxygenase (5-LO), the initial key enzyme of the leukotriene pathway. These drugs are now included among the effective therapies of asthma but appear, in the few clinical studies performed, to be an insufficient single therapeutic approach in other inflammatory diseases. Drugs able to block equally well both COX and 5-LO metabolic pathways (dual inhibitors) have been developed and experimentally evaluated in the last few years, but none are available on the market yet. The pharmacological rationale at the basis of their development is strong, and animal studies are indicative of a wide range of anti-inflammatory activity. What appears most impressive from the available studies on dual inhibitors is their almost complete lack of gastric toxicity, the most troublesome side effect of NSAIDs. The mechanism of the gastric-sparing properties of these drugs is not yet completely understood; however, it appears that leukotrienes significantly contribute to gastric epithelial injury particularly when these compounds represent the major arachidonic acid derivatives present in the gastric mucosa after inhibiton of prostanoid production.

The use of anti-inflammatory drugs in cancer pain

The role of non-steroidal anti-inflammatory drugs (NSAIDs) in cancer pain has been well established in the treatment of mild pain and also alone or in association with opioids for the treatment of moderate to severe pain. Acutely, NSAIDs may be more than mild analgesics, and may provide additional analgesia when combined with opioids. However, NSAIDs have ceiling effects and there is no therapeutic gain from increasing dosages beyond those recommended. As there is no clearly superior NSAID, the choice should be based on experience and the toxicity profile that probably relates to the COX-1:COX-2 ratio. Among the older drugs, ibuprofen seems to have these properties.Non-steroidal anti-inflammatory drugs have been shown to have an opioid-sparing effect. Although the value of a simple narcotic-sparing effect may be questioned in cancer pain treatment, the use of NSAIDs may be useful when the increase in opioid dosage determine the occurrence of opioid toxicity. Like opioids, NSAIDs should not be considered analgesics for a specific type or cause of pain. There is a lack of evidence for any difference between different routes of NSAIDs administration. The long-term toxicity of NSAIDs in cancer pain is poorly defined due to a lack of studies. A variety of strategies have been used in an attempt to reduce the risks associated with NSAID therapy. Those NSAIDs that are weak COX-1 inhibitors may be preferred. In addition, concomitant administration of misoprostol is recommended in patients at increased risk for upper gastrointestinal complications.

The effect of etodolac on bile salt and histamine-mediated gastric mucosal injury in the rat

The effect of the selective cyclo-oxygenase-type-2 (COX-2) inhibitor etodolac on gastric mucosal integrity and gastric acid secretion was investigated in the rat. Etodolac was given in doses comparable with those being used in man for therapy of rheumatic conditions. The effect of etodolac was studied in the presence of a mild barrier breaker and in the presence of increased rates of endogenous acid secretion. In conscious pylorus-ligated rats, etodolac given intragastrically in 16 or 32 mg /kg for 3 h did not by itself give rise to visible gastric mucosal injury. Etodolac, however, exacerbated gastric mucosal injury evoked by intragastric application of acidified sodium taurocholate (5 mM in 150 mM HCl) in a dose-dependent manner. This effect of edotolac was independent of changes in gastric acid secretory responses. In rats whose gastric acid secretion was stimulated by intraperitoneal histamine (5 mg/kg), and etodolac (given i.g. in doses of 16 or 32 mg/kg) also increased gastric mucosal injury caused by histamine dose-dependently in the 3-h pylorus-ligated rats. Etodolac decreased gastric mucus in the saline- and in the sodium taurocholate-treated rats. In urethane-anaesthetized acute gastric fistula rats, intragastric etodolac (32 mg/kg) did not modify basal gastric acid secretion. Our data suggest that etodolac, a selective COX-2 inhibitor, impairs gastric mucosal resistance and can exacerbate gastric mucosal injury caused by other mucosal barrier breaking agents. Cyclooxygenase type-2 thus contributes to the gastric mucosal defences.

Photosensitivity to ketoprofen: mechanisms and pharmacoepidemiological data

The topical use of nonsteroidal anti-inflammatory drugs (NSAIDs), widely used for moderate acute and chronic painful conditions, is one of several strategies used to improve the tolerability profile of NSAIDs, particularly with regard to gastric and renal adverse effects. However, topical NSAIDs can induce photosensitivity. Among the different NSAIDs used topically, ketoprofen has often been implicated in photosensitivity reactions. Photosensitivity includes both phototoxic and photoallergic reactions. Phototoxicity can be studied in the cell system and on biological targets such as cellular membranes or DNA. In hepatocyte cultures, data suggest that radical intermediates play a role in ketoprofen-photosensitised damage by cell membrane lysis. Photosensitised lysis of red blood cells has been employed as an indicator of membrane damage. Ketoprofen irradiation promotes the photolysis of erythrocyte suspensions. The drug is able to induce photoperoxidation of linoleic acid in the photo-induced lipid peroxidation process. The results obtained from the addition of radical scavengers suggest the involvement of free radicals in these processes. Ketoprofen may induce DNA damage in vitro upon irradiation. DNA, in the presence of ketoprofen, undergoes single strand breaks involving hydroxyl radicals as evidenced by the use of scavengers. Simultaneously with single strand breaks, pyrimidine dimers are formed by an energy transfer mechanism. The oxygen-dependence of both processes suggest competition between a radical process leading to DNA cleavage and a poorly efficient energy transfer between ketoprofen and pyrimidines at the origin of the dimerisation process. Photoallergy is due to a cell-mediated hypersensitivity response involving immunological reactions. Therefore, it only occurs in previously sensitised individuals and requires a latency period of sensitisation. Among NSAIDs, ketoprofen is the main drug involved in this photoallergic contact dermatitis. Cross-sensitivity reactions with other arylpropionic acid derivatives, such tiaprofenic acid, fenofibrate or oxybenzone-harbouring benzoyl ketone or benzophenone may also occur. Finally, the higher frequency of such adverse reactions with ketoprofen could be accounted for by its chemical structure and the variety of chemical reactions that give rise to phototoxic effects. The widespread and repeated use of these agents may lead to sensitisation, incurring a greater risk of systemic allergic reactions with oral NSAIDs or other drugs recognised to induce cross-reactions. Physicians and pharmacists should advise patients and inform them of the risks of topical NSAIDs which are often dispensed as over the counter drugs.

Are the biologic and clinical effects of the COX-2-specific inhibitors an advance compared with the effects of traditional NSAIDs?

This has been an unusual year for the accumulation of evidence regarding the clinical effects of inhibition of cyclooxygenase (COX)-1 and COX-2. This article reviews the available data regarding the clinical effects of the new COX-2-specific inhibitors, and speculates about the importance of the data as they relate to the treatment of patients with chronic pain and/or inflammation.

Diagnosis and treatment of nonsteroidal anti-inflammatory drug-associated upper gastrointestinal toxicity

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely prescribed in the United States to treat pain and reduce inflammation from chronic inflammatory disorders such as rheumatoid arthritis and osteoarthritis. Approximately 40% of older Americans take NSAIDs. Chronic NSAID use carries a risk of peptic ulcer and other gastrointestinal disturbances. This article reviews the diagnosis of medication-induced ulcers based on clinical presentation, laboratory tests, and endoscopic findings to assist the clinician in early diagnosis and appropriate therapy. Risk factors for NSAID-induced ulcers include old age, poor medical status, prior ulcer, alcoholism, smoking, high NSAID dosage, prolonged NSAID use, and concomitant use of other drugs that are gastric irritants, such as alendronate, a bone resorption inhibitor prescribed for osteoporosis. Appropriate treatment options for patients with medication-induced ulcers include dosage reduction, medication substitution, medication withdrawal, antiulcer therapy, and discontinuation of other gastrotoxic drugs.

Prophylaxis and treatment of NSAID-induced gastroduodenal disorders

A significant percentage of patients taking nonsteroidal anti-inflammatory drugs (NSAIDs) experience some type of adverse gastrointestinal symptoms, lesions of the gastroduodenal tract being clinically the most relevant. NSAIDs cause gastrointestinal damage by 2 independent mechanisms: a topical effect, which is pH and pKa related, and a systemic effect mediated by cyclooxygenase (COX) inhibition with a reduction in prostaglandin synthesis. Using endoscopy, gastroduodenal lesions identified include subepithelial haemorrhages, erosions and ulcers. The prevalence of ulceration in NSAID users has been reported as being between 14 and 31% with a 2-fold higher frequency of gastric ulcers compared with duodenal ulcers. Among the strategies used to decrease the risk of ulcer development are: (i) the use of analgesics other than NSAIDs; (ii) use of the lowest possible dosage of NSAID; (iii) the use of a COX-2 selective NSAID; (iv) the use of low doses of corticosteroids instead of NSAIDs; (v) avoidance of concomitant use of NSAIDs and corticosteroids; and (vi) use of preventive therapy. In an attempt to reduce the incidence of NSAID-induced gastrointestinal lesions, the following approaches have been proposed: (i) use of the prostaglandin analogue misoprostol, which is an antiulcer drug which has been proven to be as effective in the prevention of NSAID-induced gastric and duodenal ulcers as in the reduction of serious upper gastrointestinal complications; (ii) histamine H2 receptor antagonists (H2 antagonists), e.g. ranitidine, cimetidine and famotidine, which are useful in the prevention of NSAID-induced duodenal ulcers during long term treatment, but not in the prevention of NSAID-induced gastric ulcers; (iii) proton pump inhibitors, e.g omeprazole, and pantoprazole, whose efficacy in preventing NSAID-associated ulcers has been recently demonstrated; and (iv) barrier agents, e.g. sucralfate, which cannot be recommended as prophylactic agents to prevent NSAID-induced gastropathy. The first step in the treatment of NSAID-associated ulcers lies in a reduction in the dosage of the NSAID or discontinuation of the drug. If NSAID treatment cannot be withdrawn, a proton pump inhibitor appears to be the most effective treatment in healing ulcers, accelerating the slow healing observed with H2 antagonists.

The use of analgesics in the management of pain in rheumatic diseases

Pain is the most common complaint of patients who see rheumatologists. In this article, the current treatment options for pain are reviewed; these include acetaminophen, nonsteroidal anti-inflammatory drugs, new specific cyclooxygenase-2 inhibitors, opioid analgesics, centrally acting muscle relaxants, antidepressants, and topical analgesics and counterirritants. The doses of medication and known adverse effects of these medications are highlighted.

Economic and gastrointestinal safety comparisons of etodolac, nabumetone, and oxaprozin from insurance claims data from patients with arthritis

This study was conducted to compare the effect of etodolac, nabumetone, and oxaprozin use on gastrointestinal (GI) safety and associated costs based on insurance claims information from practice settings. Data were obtained from a national claims database (MarketScan) for the years 1992 to 1994. The claims data of interest were for patients with arthritis who had used etodolac, nabumetone, or oxaprozin exclusively during a 9-month follow-up period (ONLY groups), or these drugs plus (PLUS groups) the other nonsteroidal anti-inflammatory drugs (NSAIDs) ibuprofen, naproxen, diclofenac, sulindac, piroxicam, ketoprofen, or indomethacin. For each group, we obtained information on the use of inpatient and outpatient services for GI-related events and the associated costs. All GI admissions were classified as NSAID-induced or possibly NSAID-induced events based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9 CM) codes. All outpatient upper GI ulcers or bleeding episodes were also identified by specific ICD-9 CM code. There were no significant between-group demographic differences. The proportions of patients with NSAID-induced and possibly NSAID-induced GI admissions were 0.1% and 0.4% for the etodolac-ONLY, 0.3% and 1.0% for the nabumetone-ONLY, and 0.1% and 0.5% for the oxaprozin-ONLY groups, respectively (P > 0.05), and a similar pattern was observed among the PLUS groups. In outpatient settings, 3.9%, 4.2%, and 4.9% of the etodolac-, nabumetone-, and oxaprozin-ONLY patients, respectively (P > 0.05), and 6.0%, 5.3%, and 4.7% of the etodolac-, nabumetone-, and oxaprozin-PLUS patients, respectively, had at least one upper GI ulcer/bleeding claim (P > 0.05). The total health care costs for 9 months were approximately $3000 each for the etodolac-, nabumetone-, and oxaprozin-ONLY groups. Oxaprozin, nabumetone, and etodolac had similar GI-safety and associated-costs profiles based on information from practice settings. Also, in patients who used multiple NSAIDs, the groups did not differ in their GI-safety and cost profiles.

Effects of chronic treatment with indomethacin at clinically relevant doses on intestinal tissue 6-keto prostaglandin F1 alpha and leukotriene B4 level in relation to gastroenteropathy

This study investigated the effects of indomethacin at clinically relevant doses and its chronic usage on intestinal pathology, survival time and intestinal tissue 6-keto prostaglandin F1 alpha and leukotriene B4 level in rats during various periods with different doses. Indomethacin was administered ranging from 0.625 to 5 mg/kg. When used in doses of 0.625 and 1.25 mg/kg, indomethacin caused no apparent intestinal lesions or death during a treatment period of 30 days. On the other hand, all rats died in 7 days when 5 mg/kg of indomethacin was given. Mortality rate reached 53.3% in seven days in the group where 3.75 mg/kg indomethacin was given. The minimal dose of indomethacin, which induced intestinal ulcer and death, was 2.5 mg/kg. The main pathological findings were intestinal ulcers, but no macroscopic and microscopic changes were observed in the stomach. Intestinal tissue 6-keto prostaglandin F1 alpha and leukotriene B4 levels were quantified by enzyme immunoassay after homogenisation and extraction of tissue. In dose-dependent studies, only the dose of indomethacin, 3.75 mg/kg, significantly inhibited intestinal tissue 6-keto prostaglandin F1 alpha levels during seven days application period (197.39 +/- 24.26 vs 383.66 +/- 46.68 ng/g tissue, treatment vs control). 2.5 mg/kg of indomethacin caused no intestinal ulceration on 4th day, however, it significantly inhibited intestinal tissue 6-keto prostaglandin F1 alpha levels on 4th day in time-dependent studies (190.3 +/- 26.62 vs 383.66 +/- 46.68 ng/g tissue, treatment vs control). Neither dose-dependent nor time-dependent indomethacin administration changed intestinal tissue leukotriene B4 level. The results of this study indicated that indomethacin produced enteropathy rather than gastropathy when used chronically in clinically relevant doses in rats. Inhibition of prostaglandin synthesis, which was estimated by quantification of intestinal tissue 6-keto prostaglandin F1 alpha level, seemed not to be a prerequisite for its enteropathic effect.

Pharmacologic management of pain and inflammation in athletes

This article attempts to concisely present some of the scientific basis of the pharmacology of anti-inflammatory medications. The clinical use and application of anti-inflammatories is also addressed. The information is designed to assist the clinician to develop a sound approach in selecting the appropriate treatment plan for their patients.

The cost-effectiveness of misoprostol in preventing serious gastrointestinal events associated with the use of nonsteroidal antiinflammatory drugs

OBJECTIVE

To reexamine the cost-effectiveness of misoprostol, using data from a recently published placebo-controlled trial of misoprostol in > 8,000 patients with rheumatoid arthritis (RA) taking nonsteroidal antiinflammatory drugs (the Misoprostol Ulcer Complications Outcome Safety Assessment [MUCOSA] study).

METHODS

Actual clinical events and the rates of endoscopies and upper gastrointestinal (GI) radiographic series, hospitalizations, and surgery for these events were derived from the MUCOSA study and used in a decision analysis. Estimates of costs for the management of these events were derived from the Ontario Case Cost Project database and published economic evaluations; costs were adjusted to 1994 Canadian dollars. Incremental cost-effectiveness (from the viewpoint of the provincial health care plan in Canada) was calculated for the original trial population (risk of a serious GI complication 1%) and for the subsets of patients with medium (3%) and high (6%) risk.

RESULTS

For the original study population, averting 1 serious GI complication by prescribing misoprostol would cost an additional $94,766 (Canadian; range $60,286-137,146). For patients with previous peptic ulcer disease (medium risk), the cost would be $14,943 (range $10,912-32,157), and for patients with previous peptic ulcer disease and age > 75 (high risk), the cost would be $4,101 (range $-220 to $18,146).

CONCLUSION

Prescribing misoprostol for all patients with RA who are > or =52 years old costs $94,766 for each additional GI event averted. However, when patients at higher risk are specifically selected, the cost per averted GI complication is markedly reduced. These results, based on actual serious event rates and actual data on endoscopies and upper GI series, hospitalizations, and surgeries, provide a better estimate of the true cost-effectiveness of misoprostol than previous analyses based on endoscopic data and modeling of all resource utilizations.

[Risk of ulcer and its prophylaxis in therapy with non-steroidal antirheumatic drugs]

Nonsteroidal antiinflammatory drugs (NSAIDs) are among the most frequently prescribed drugs in western countries. The high incidence of adverse gastrointestinal effects which are potentially life-threatening require steps for prevention. The use of NSAIDs should be restricted to patients with inflammatory rheumatic diseases. If NSAIDs are indicated it is important to identify patients who are at high risk to develop serious gastrointestinal side effects. These patients should receive Misoprostol at a dose of 2 to 3 x 200 micrograms per day. Up to date Misoprostol is the only drug with proven efficacy with respect to the prevention of gastroduodenal ulcer and its complications. NSAIDs inhibit the key enzyme of prostaglandin synthesis, the cyclooxygenase. Recently published data show that 2 isoenzymes of the cyclooxygenase exists. Cyclooxygenase-1 is primarily involved in the maintenance of organ function whereas cyclooxygenase-2 is expressed in inflamed tissue. Specific cyclooxygease-2 inhibitors have been developed. Clinical trials have to prove if the concept of a selective cyclooxygenase-2 inhibition with high antiinflammatory potency but lack of gastrointestinal side effects holds true in humans.

Management of NSAID-induced gastropathy: an economic decision analysis

The use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with a 2% to 4% annual incidence of serious gastrointestinal complications. These adverse clinical outcomes, and the strategies used to prevent their occurrence, translate into a significant economic burden. A decision-analysis model was constructed to contrast the 6-month costs associated with various approaches to preventing and managing NSAID-induced gastropathy and to evaluate the economic impact of two treatment regimens using fixed-dose formulations of diclofenac/misoprostol. After incorporating expected medical out-comes and predicted practice patterns, 6-month per-patient costs were derived from the model for each of five treatment regimens: (1) NSAID alone; (2) NSAID with a histamine2-receptor antagonist; (3) NSAID with coprescribed misoprostol; (4) diclofenac/misoprostol 50 mg/200 micrograms TID/BID; and (5) diclofenac/misoprostol 75 mg/200 micrograms BID. The combined diclofenac/misoprostol regimens demonstrated an 18.6% per-patient cost advantage compared with the combined NSAID regimens. Based on a 6-month period, this cost savings translated into a $214.00 per-patient overall cost savings ($1153.00 per patient for NSAID regimens versus $939.00 for diclofenac/misoprostol regimens). The magnitude of this difference was verified by Monte Carlo simulation. Despite the considerable cost difference, sensitivity analyses revealed that our model was robust and that no single variation substantially influenced the results. Given the lack of long-term prospective, comparative clinical-outcomes studies in this area, this decision analysis provides guidance to clinicians in developing a rational and cost-effective approach to the treatment of patients requiring chronic NSAID therapy.

Peptic ulcer disease in the 1990s: an Asian perspective

Peptic ulcer disease is still a common disease in many parts of Asia, although it is less common today than it was 2-3 decades ago. Contrary to this general trend, peptic ulcers are on the rise in the elderly, particularly elderly females. Two important factors that could explain the observed changes in the trends of peptic ulcer disease are: Helicobacter pylori and NSAID. The seroprevalence of H. pylori, determined in three previous studies, would appear to have decreased over the last few decades, while NSAID and aspirin are used increasingly for arthritis, cerebrovascular disease and coronary artery disease. The major complication of peptic ulcer disease is gastrointestinal haemorrhage and in the 1990s endoscopic haemostatic therapy has replaced surgery as the treatment of choice. Treatment of peptic ulcer disease caused by H. pylori is directed at eradication of H. pylori itself; four classes of drug regimens are currently available for this. Antibiotic resistance, particularly metronidazole resistance, is an important factor that determines the outcome of therapy. Metronidazole resistance is reported to be present in 50% of all strains of H. pylori in Hong Kong and Singapore, and is present in 80-90% of all strains in India. Eradication rates in Asia, may for this reason, differ from those in the West, if the regimen contains metronidazole. Treatment of NSAID-associated ulcer consists of discontinuation of NSAID, if possible, and administration of anti-secretory drugs such as H2 blockers, proton pump inhibitors or mucosal protective agents. Co-prescription with misoprostol has been shown to reduce the risk of NSAID-induced ulcer. New NSAID or NO NSAID are being developed with few gastrointestinal side effects.

Hepatocyte growth factor as a key to modulate anti-ulcer action of prostaglandins in stomach

Although the clinical efficacy of prostaglandins (PGs), especially on gastric mucosal injuries induced by nonsteroidal antiinflammatory drugs, is widely appreciated, their mechanism of action, apart from acid suppression, is quite unclear. In this study, we have established a primary culture system of human gastric fibroblasts and clearly demonstrated that PGs strongly induce the expression of hepatocyte growth factor (HGF) in the fibroblasts, which is mediated by PGE specific receptor, EP2 or EP4. Since HGF facilitates repair and protection of gastric epithelial cells in a paracrine manner, it is assumed that some of the beneficial effects of PGs may be mediated by HGF. To confirm this assumption, we established a simplified in vitro culture gastric mucosal model which consists of gastric epithelial cells and gastric fibroblasts. Using the model, we performed a round wound restitution assay. PGE1 remarkably accelerated restitution which was completely inhibited by anti-HGF antibody, indicating that the action was mediated by HGF. To confirm these in vitro data, we further demonstrated that HGF mRNA expression is downregulated at the edges of nonsteroidal antiinflammatory drug-induced gastric ulcers where PGs should be depleted. In summary, we proposed that gastric fibroblasts are newly recognized targets of PGs, and HGF produced by human gastric fibroblasts may be a key factor for anti-ulcer action of PGs in the stomach.

Advanced and controlled drug delivery systems in clinical disease management

Advanced and controlled drug delivery systems are important for clinical disease management. In this review the most important new systems which have reached clinical application are highlighted. Microbiologically controlled drug delivery is important for gastrointestinal diseases like ulcerative colitis and distally localized Crohn's disease. In cardiology the more classic controlled release systems have improved patient compliance and decreased side effects. In the treatment of intractable pain the spinal and transdermal route is well documented. In neurology the flattened peak-through levels of antiepileptic drugs and anti Parkinson's drugs represents a more predictable kinetic profile. Tracheal delivery of corticosteroids and sympaticomimetics in asthma and Chronic Obstructive Pulmonary Disease is fully accepted in clinical practice: delivery by this route results in better efficacy and a better safety profile. In gynaecology the delivery of pulsatile hormones (LHRH) is used for pregnancy induction, while transdermal oestrogens are promising in the prevention of osteoporosis. In surgical practice the use of antibiotic impregnated bone cement and antibiotic impregnated biodegradable collagens is well established. To prevent infections intravascular catheters coated with heparin or antibiotics are used. In ophthalmology the Ocusert systems provide a controlled release of different drugs in the eye. Most spectacular is the clinical introduction of the first liposomal drugs; amfotericine B and daunorubicine. Liposomal formulations of these drugs have enhanced activity and decreased toxicity compared to conventional formulations.

Cyclooxygenase 1 and 2 in rheumatic disease: implications for nonsteroidal anti-inflammatory drug therapy

OBJECTIVES

Prostaglandin synthase (cyclooxygenase) is now known to exist in two separate isoforms, termed prostaglandin synthase 1 and 2 (or COX1 and COX2). This has prompted a dramatic increase in research regarding the contribution of these isoforms to inflammatory disease and their relationship to the efficacy and safety of nonsteroidal anti-inflammatory drugs (NSAIDs). The emerging picture is that COX1 is responsible for maintaining prostaglandin synthesis in the gastric mucosa, platelets, and kidney, whereas COX2 is responsible for prostaglandin production in inflamed tissues, including rheumatoid arthritis (RA) synovium. This review examines the validity of the hypothesis that NSAIDs exhibiting selectivity for COX2 demonstrate an improved safety and efficacy profile when compared with NSAIDs exhibiting selectivity for COX1.

METHODS

Literature on the efficacy and safety (gastric, renal, and hemostatic) of various NSAIDs are compared with published data on their relative COX1 and COX2 in vitro specificity.

RESULTS

No differences in clinical efficacy are evident between NSAIDs exhibiting preferential activity for either COX1 or COX2. NSAIDs representing the extremes in terms of selectivity for COX1 or COX2 do exhibit some differences with respect to gastric, renal, and hemostatic safety; those exhibiting a preferential action on COX2 are generally less toxic than those exhibiting a preferential activity on COX1. Exceptions do exist.

CONCLUSIONS

There is some support for the hypothesis that NSAIDs exhibiting a preferential action on COX2 are safer than those exhibiting a preferential activity on COX1, but there exists no support for improved efficacy. A strict correlation does not exist between the COX1 and COX2 specificity and the gastric, renal, and hemostatic toxicity of NSAIDs. This lack of correlation is believed to stem from the fact that both the safety and efficacy of NSAIDs may result from mechanisms distinct from prostaglandin inhibition. Preferential COX2 activity can reduce the level of toxicity for a given NSAID but may not be sufficient to overcome toxicities resulting from other mechanisms.

Nonsteroidal anti-inflammatory drugs: practical and theoretical considerations in their selection

Nonsteroidal anti-inflammatory drugs (NSAIDs) are prescribed frequently for patients with painful musculoskeletal conditions: Each year, physicians write approximately 60 million NSAID prescriptions. Because of the magnitude of patient exposure, gastrointestinal and other side effects of NSAIDs are a significant clinical concern. The mechanism of action of NSAIDs is inhibition of cyclooxygenase with secondary inhibition of proinflammatory prostaglandins. This mechanism also accounts for gastrointestinal toxic side effects of NSAIDs. Two forms of cyclooxygenase, cox-1 and cox-2, appear to be differentially inhibited by NSAIDs. Because cox-1 is responsible for maintaining normal physiologic function in gastric mucosa and other tissue, "ideal" NSAIDs would suppress only cox-2. The design of future NSAIDs-related peptic ulceration is characterized by its location in the gastric antrum, asymptomatic nature, and ability to develop through both topical and systemic effects of NSAIDs. Major risk factors for patients with rheumatoid arthritis include age >60 years, magnitude of disability, concomitant use of corticosteroids, larger doses/longer duration of NSAID treatment, and a history of peptic ulcer disease. A prophylactic strategy includes the identification of high-risk patients and, if NSAIDs must be used, the addition of misoprostol.

Drug-related admissions to an Australian hospital

This study was conducted to determine the prevalence of drug-related hospital admissions in southern Tasmania, Australia. The causes of consecutive admissions to medical wards of the Royal Hobart Hospital were reviewed. Comprehensive data were collected over a 10-week period on 691 admissions (median age: 67 years and range: 11-97 years; 50.8% males). Sixty-eight (9.8%) of the admissions were classified as being either probably or definitely drug-related. Most of these admissions were attributable to intentional overdose (38.2%) or an adverse drug reaction (30.9%). The overdoses often involved benzodiazepines or antipsychotics. Gastrointestinal bleeding related to the use of nonsteroidal anti-inflammatory drugs was the most common adverse drug reaction (38.1% of all reactions). Other drug-related admission categories were poor compliance (14.7%), dosage decrease or therapy cessation by a doctor producing an exacerbation of symptoms (7.4%), substance abuse (4.4%) and drug interaction (4.4%). Patients with a drug-related admission were, on average, younger than the other medical admissions, with no significant difference in gender. Patients admitted due to an overdose or substance abuse were younger than other drug-related admissions and non-drug related admissions. In conclusion, this study has determined that almost 10% of medical admissions to the hospital are drug-related and it is estimated that 40 to 50 elderly people are admitted each year suffering from gastrointestinal bleeding related to nonsteroidal anti-inflammatory drugs.

Postsurgical complications in older patients. The role of pharmacological intervention

The number of elderly patients undergoing surgery has been rapidly increasing during the last few years. Following surgical interventions, high rates of mortality and morbidity have been reported in the most advanced age groups. Nevertheless, perioperative evaluation and postoperative care are the major determinants of the overall outcome. Postsurgical complications are common in advanced age, since multiple pathology is often present in geriatric patients. Furthermore, the decreased efficiency of homeostatic mechanisms may facilitate the development of multiple organ failure (MOF), even as a consequence of apparently slight alterations in immune, cardiac or respiratory systems. Thus, prompt recognition and treatment of any complication often prevents the development of irreversible conditions. While cardiac and pulmonary complications account for 50% of early postoperative adverse events, infections, thromboembolism, renal failure, stress ulcers and coagulation disorders may occur well after surgical procedures. An important part of postoperative geriatric care is the diagnosis and correction of fluid, electrolyte and acid-base disturbances. These disturbances may manifest as mild, atypical signs, such as slight neuromuscular depression or delirium. Yet, they often constitute life-threatening conditions that should be rapidly and properly corrected. Finally, it should be remembered that, due to the frequent use of multiple drugs, elderly patients are at high risk of developing adverse drug reactions. Thus, the treatment of postoperative complications requires a strong rational effort to disentangle the combined effects of aging, drugs and pathology.