Physicians' communication of risks from non-steroidal anti-inflammatory drugs and attitude towards providing adverse drug reaction information to patients

RATIONALE, AIMS, AND OBJECTIVES

Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently prescribed for orthopaedic conditions, therefore this study aimed to explore orthopaedic physicians' perceptions of their role in NSAID-risk communication, their attitudes towards the necessity of informing patients about adverse drug reactions (ADR), and factors associated with these.

METHODS

Self-administered questionnaires were mailed to all 206 orthopaedic physicians working at hospitals in Northeastern Thailand. Attitudes were assessed using 17 statements and total scores classed as poor, moderate and good attitude.

RESULTS

Sixty-six questionnaires were returned (32.04%). The responses showed that 75% of physicians claimed to communicate NSAID ADR information, more frequently about gastrointestinal (GI) complications, than about renal and cardiovascular (CVS) complications. ADR management (36%) and monitoring (30%) were not frequently communicated. The time spent with patients was associated with provision of ADR and monitoring advice. Renal function was the risk factor of greatest concern for prescribing any NSAID, followed by history of GI complications, and allergy for non-selective NSAIDs, and history of CVS diseases and age for selective COX-2 NSAIDs. Most physicians (41) had moderate attitude towards providing information and 24 good attitude. Fewer physicians working in tertiary hospitals than general and community hospital physicians considered that time limitations prevented counseling and that patient information leaflets offered easily accessible information. Additionally, more physicians who did not inform patients about ADRs agreed that ADR communication can lead to anxiety and discontinuing treatment.

CONCLUSION

The study indicates that, although orthopaedic physicians had positive attitudes towards providing ADR information to patients, improvement is needed in communicating NSAID risk information.

Uso de anti-inflamatórios e analgésicos por uma população de idosos atendida na Estratégia Saúde da Família

ResumoEste estudo objetivou analisar a prevalência do uso de anti-inflamatórios e analgésicos em idosos da Estratégia Saúde da Família de Porto Alegre-RS, bem como investigar fatores associados: dados sociodemográficos e de saúde; uso contínuo ou se necessário da medicação; indicação médica ou automedicação. A coleta de dados ocorreu entre março de 2011 e dezembro de 2012. Os agentes de saúde comunitários aplicaram um questionário com dados sociodemográficos, de saúde e uso de medicamentos. Foram estudados os anti-inflamatórios não esteroidais, glicocorticoides, analgésicos não opioides e opioides de uso oral. Foram incluídos 758 idosos e o uso de anti-inflamatórios e analgésicos era feito por 28,8%. O paracetamol e o ibuprofeno foram os mais utilizados. No que diz respeito à autopercepção de saúde, quanto pior a saúde relatada, maior o uso da terapêutica (p<0,001). A doença hepática e artrose/artrite/reumatismo mostraram estar associadas ao uso de anti-inflamatórios e analgésicos (p<0,001). A prevalência de uso de anti-inflamatórios e analgésicos foi considerada moderada quando comparada a estudos prévios (28,8%). Além disso, a maioria dos idosos fazia uso desses medicamentos quando era preciso, provavelmente porque sentia dores leves a moderadas, não sendo necessário o uso contínuo da medicação ou também por sofrer com os efeitos adversos desses medicamentos, optando por usá-los esporadicamente.

Underuse of proton-pump inhibitors in older patients newly starting NSAID treatment

OBJECTIVE

Proton pump inhibitors (PPIs) are recommended for the prevention of traditional non-steroidal anti-inflammatory drugs (tNSAIDs)-related ulcer complications in high-risk patients. We aimed to study to which extent older persons initiating tNSAIDs with and without oral corticosteroids receive PPIs and whether sex and age influence treatment.

METHODS

We analysed claims data of the German health insurance company BARMER GEK, covering about 9 million persons. A cohort of new users of tNSAIDs aged 65 years and older starting treatment from 1 January 2011, through 1 December 2012 was included. Concurrent use of oral corticosteroids was assessed within the 28 days before the index date. Persons were categorised as users of PPIs if they filled a prescription within 28 days before or after the index prescription.

RESULTS

A total of 83,326 persons met the inclusion criteria (64.1% females; mean age: 74.7 years). Of these new users of tNSAID, 27.8% received PPIs within 28 days before or after the index date (females: 29.4% and males: 25.0%). Of the 2857 persons with concurrent prescriptions of oral corticosteroids, 42.8% also received PPIs (females: 43.4% and males: 41.8%). An increase in prescribing of PPIs with age was found in all new users as well as in those concurrently receiving oral corticosteroids.

CONCLUSIONS

We found that gastroprotective agents are not prescribed to older new users of tNSAIDs as recommended. When compared with earlier studies, adherence to guidelines still remains low.

Co-prescription of gastroprotective agents and their efficacy in elderly patients taking nonsteroidal anti-inflammatory drugs: a systematic review of observational studies

BACKGROUND & AIMS

Guidelines recommend prescribing gastroprotective agents (proton pump inhibitors, misoprostol) to older patients (primarily ≥65 years old) taking nonsteroidal anti-inflammatory drugs (NSAIDs) to prevent gastrointestinal ulcers. Older individuals are underrepresented in clinical trials of these agents. We systematically reviewed evidence from observational studies on the use of gastroprotective agents in elderly patients and their ability to prevent NSAID-related ulcers in this population.

METHODS

We performed a systematic search of Embase and MEDLINE and identified 23 observational studies that focused on elderly patients and reported data on co-prescription of gastroprotective agents and NSAIDs and/or the effectiveness of the agents in preventing gastrointestinal events in NSAID users. We collected data on rates of co-prescription and NSAID-related gastrointestinal events in patients with and without gastroprotection.

RESULTS

A median of 24% (range, 10%-69%) of elderly patients taking NSAIDs received a co-prescription for gastroprotective agents; this percentage was only slightly higher in the oldest age groups. All studies of efficacy showed a positive effect of gastroprotection. However, the adjusted results were not suitable for synthesis, and the 5 studies reporting unadjusted results were too heterogeneous for meta-analysis (I(2) = 97%). The studies differed in outcomes, definitions of co-prescription, and differences in baseline risk factors between patients with and without gastroprotection. None of the studies assessed adverse effects of gastroprotective agents. The 2 cost-effectiveness studies reached opposing conclusions.

CONCLUSIONS

In a systematic review, the observational evidence for the efficacy of gastroprotective agents in preventing NSAID-associated gastrointestinal events was in agreement with results of randomized controlled trials. However, because of heterogeneity of included studies, it is not clear what the effect would be if more patients were treated, or at what age gastroprotection should be recommended. We offer suggestions to facilitate comparison with other work and address the questions of risk and benefit in relation to age.

Nonsteroidal anti-inflammatory drugs, gastroprotection, and benefit-risk

Background

Gastroprotective agents (GPA) substantially reduce morbidity and mortality with long-term nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin.

Objective

To evaluate efficacy of NSAIDs, protection against NSAID-induced gastrointestinal harm, and balance of benefit and risk.

Methods

Free text searches of PubMed (December 2012) supplemented with “related citation” and “cited by” facilities on PubMed and Google Scholar for patient requirements, NSAID effectiveness, pain relief benefits, gastroprotective strategies, adherence to gastroprotection prescribing, and serious harm with NSAIDs and GPA.

Results

Patients want 50% reduction in pain intensity and improved fatigue, distress, and quality of life. Meta-analyses of NSAID trials in musculoskeletal conditions had bimodal responses with good pain relief or little. Number needed to treat (NNTs) for good pain relief were 3 to 9. Proton pump inhibitors (PPI) and high-dose histamine-2 receptor antagonists (H₂RA) provided similar gastroprotection, with no conclusive evidence of greater PPI efficacy compared with high-dose H₂RA. Prescriber adherence to guidance on use of GPA with NSAIDS was 49% in studies published since 2005; patient adherence was less than 100%. PPI use at higher doses over longer periods is associated with increased risk of serious adverse events, including fracture; no such evidence was found for H₂RA. Patients with chronic conditions are more willing to accept risk of harm for successful treatment than their physicians.

Conclusion

Guidance on NSAIDs use should ensure that patients have a good level of pain relief and that gastroprotection is guaranteed for the NSAID delivering good pain relief. Fixed-dose combinations of NSAID plus GPA offer one solution.

Use of non-steroidal anti-inflammatory drugs and proton pump inhibitors in correlation with incidence, recurrence and death of peptic ulcer bleeding: an ecological study

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) and proton pump inhibitors (PPIs) are regarded as two types of drugs that respectively increase and decrease the risk of peptic ulcer bleeding. However, their relation to occurrence, recurrence and death of bleeding in the population level is not clear.

STUDY OBJECTIVE

To clarify recent calendar-time correlations between sales of NSAIDs and PPIs and the occurrence of peptic ulcer bleeding, re-bleeding and death.

DESIGN

Ecological study.

RESULTS

The time trend of peptic ulcer bleeding did not correlate with PPI sales but did correlate with NSAIDs in mem (R(male)=0.6571, P(male)=0.05). Sales of PPIs (inverse) and NSAIDs correlated with re-bleeding in women (R(male)=-0.8754, P(male)=0.002 and R(female)=0.7161, P(female)=0.03, respectively), but not in men. An inverse correlation between PPI sales and 30-day death after bleeding was found (R(male)=-0.9392, P(male)=0.0002 and R(female)=-0.8561, P(female)=0.003), and NSAID sales were found to correlate with increased death after bleeding ((R(male)=0.7278, P(male)=0.03, R(female)=0.7858, P(female)=0.01).

CONCLUSIONS

The sales of NSAIDs and PPIs correlate with recurrence of peptic ulcer bleeding in women and death after peptic ulcer bleeding in both genders in the population level.

Musculoskeletal pain and its treatment among older home-dwelling people: ten-year changes in two Finnish birth cohorts

The purpose of this study is to evaluate the prevalence of musculoskeletal pain and the use of analgesics in two random cohorts of home-dwelling older people 10 years apart (1999 (N = 2044) and 2009 (N = 1610)) in Helsinki, Finland, and to explore which patients characteristics are associated with potential undertreatment or overtreatment of pain. In 1999, the prevalence of daily joint pain interfering with functioning was 16.4% and that of back pain 13.9% among 75-85-year-old people, the respective figures being 21.9% and 17.1% in 2009 (p < 0.001). The proportion of those patients suffering from joint pain and using prescribed analgesics for that was 35.5% in 1999 and 41.5% in 2009 (p < 0.001). The corresponding figures for patients suffering from back pain with analgesics were 38.2% and 48.2% (p < 0.001), respectively. In 2009, 66.1% suffered from any musculoskeletal pain and 28.7% of them were prescribed analgesics, the figures being more frequent among women than men. In addition to higher age, female gender, and painful conditions, also psychiatric symptoms and dizziness tended to be independently associated with analgesic prescriptions. Among persons not reporting pain (N = 545) psychiatric symptoms were overrepresented in the group using prescribed analgesics (22.4% vs. 8.1%, p < 0.05). In conclusion, musculoskeletal pain is still clearly undertreated, but the coverage has increased during 10 years. In addition to pain, several patient characteristics, functioning and psychiatric symptoms, especially, were associated with analgesic prescriptions.

Concomitant use of SSRIs, NSAIDs/aspirin and gastroprotective drugs among residents of long-term care facilities: a medical record review

BACKGROUND AND OBJECTIVES

Concomitant use of selective serotonin reuptake inhibitors (SSRIs) and nonsteroidal anti-inflammatory drugs (NSAIDs) [including aspirin (acetylsalicylic acid)] may potentiate the likelihood of upper gastrointestinal haemorrhage (UGIH). The objectives of this study were to determine the prevalence and factors associated with concomitant SSRI/NSAID use among residents of long-term care facilities, and to investigate the use of gastroprotective drugs among concomitant SSRI/NSAID users.

METHODS

The study sample comprised 1087 out of 1444 residents of all 53 long-term care wards in Helsinki, Finland, in September 2003. Data were extracted from residents' medication charts and medical records by trained nurses. Medication, diagnostic and mortality data were available for 1004 residents.

RESULTS

Among the 1004 residents (mean ± SD age 81.3 ± 10.9 years), 28% used an SSRI, 38% used an NSAID and 24% used a gastroprotective drug. Thirteen percent of residents were concomitant users of SSRIs/NSAIDs. Concomitant use was associated with diabetes mellitus (p < 0.001), previous stroke (p < 0.001) and a higher degree of co-morbidity (p < 0.001). Gastroprotective drugs were used by 27% of concomitant users of SSRIs/NSAIDs compared with 37%, 20% and 22% of SSRI users, NSAID users and non-users of SSRIs/NSAIDs, respectively. One-year all-cause mortality was similar among all groups.

CONCLUSION

The long-term facility residents in this study sample were frequently exposed to drug-drug interactions that potentiate the risk of UGIH. Only about one-quarter of concomitant users of SSRIs/NSAIDs were prescribed a gastroprotective drug. Further initiatives are needed to optimize the use of SSRIs, NSAIDs and gastroprotective drugs.

High concomitant use of interacting drugs and low use of gastroprotective drugs among NSAID users in an unselected elderly population: a nationwide register-based study

BACKGROUND

NSAIDs are commonly used in the elderly and carry significant risks of adverse events when used concomitantly with potentially interacting drugs.

OBJECTIVE

The aim of this study was to provide a valid estimate of concomitant use of potentially interacting drugs and gastroprotective agents among elderly NSAID users.

METHODS

This was a nationwide Swedish register-based study of drug prescriptions for 1 529 267 persons aged ≥65 years in 2008, using the Swedish Prescribed Drug Register. The proportions of concomitant use of potentially interacting drugs and gastroprotective agents were analysed among NSAID users, categorized by age group, sex and NSAID use, defined as: non-users, people with 0-30 days of treatment, people with >30-180 days of treatment and people with >180 days of treatment. Use of the following concomitant drugs was evaluated: potentially harmful interacting drugs, i.e. antithrombotic drugs, antihypertensive drugs or drugs for congestive heart failure (digitalis glycosides, thiazide diuretics, loop diuretics, β-adrenoceptor antagonists, calcium channel antagonists, ACE inhibitors and angiotensin II type 1 receptor antagonists [angiotensin receptor blockers]) and other drugs (systemic corticosteroids, selective serotonin reuptake inhibitors [SSRIs], methotrexate and lithium); and gastroprotective drugs.

RESULTS

In the study cohort, 257 963 (16.9%) people had collected at least one prescription for an NSAID in 2008. This use was higher in females than in males and decreased in older age groups in both sexes. In the age groups 65-69, 70-74, 75-79, 80-84 and ≥85 years, the frequencies of NSAID users were 20.6%, 20.5%, 18.9%, 15.6% and 11.6% among women, and 16.8%, 16.7%, 15.2%, 13.5% and 11.1% among men, respectively. NSAID users often concomitantly used potentially interacting drugs, e.g. over 30% used antithrombotic agents, and women had higher concomitant use of SSRIs, i.e. 12% compared with 6% in men in the youngest age group. Concomitant use of potentially harmful interacting drugs generally increased with age and with increasing use of NSAIDs. Among the eldest (age ≥85 years), concomitant drug use was stable over NSAID groups. Only 40% of regular NSAID users (i.e. those prescribed NSAIDs for >180 days) were prescribed any gastroprotective medication.

CONCLUSIONS

Prescribers should be alert to the possibility of potentially harmful interactions between NSAIDs and commonly prescribed drugs in the elderly. Increased use of gastroprotective medication might be justified in this context.

Gastro-protective strategies in primary care in Italy: the "Gas.Pro." survey

INTRODUCTION

Risk of gastrointestinal injury is relevant among users of anti-inflammatory or cardio-protective drugs. Adequate gastro-protection is warranted in high-risk patients.

AIM

To assess the perceptions and practices of Italian primary care physicians regarding gastro-protective strategies.

METHODS

Nationwide cross-sectional observational study. A 14-question survey questionnaire was administered to 112 primary care physicians throughout Italy. Data collection covered consecutive outpatient candidates for the prescription of a potentially GI harmful medication, observed in the physicians' office over a 3-week period.

RESULTS

Cohort included 3943 cases (2489 naïve and 1463 chronic NSAID/ASA users). Mean age and prevalence of cardiovascular comorbidity were significantly higher in the latter subgroup. Non-selective NSAIDs and low-dose aspirin were the most commonly prescribed drugs. Combined NSAIDS/ASA plus steroids/anticoagulant/antiplatelets were recorded in 161 cases. Helicobacter pylori status was known in only 38% of naïve and 33.2% of chronic users, being negative in 85.3% and 89.5%, respectively. When positive, H. pylori was eradicated by almost all physicians (97.9%), but in case of unknown H. pylori status, the presence of infection was investigated in only 8.6% and 14.9% of patients in the two subgroups. Gastro-protection was endorsed in 80.7% of patients, mostly PPIs (91%). In patients aged over 70, pantoprazole and lansoprazole were the preferred gastro-protective agents.

CONCLUSIONS

There is a significant over-use of gastro-protection in the primary care setting in Italy and the role H. pylori is largely overlooked. Educational efforts should be directed to a more targeted gastro-protection only for at-risk patients as well as improved adherence to recommendations for testing and treating H. pylori infection.

Sensory and vascular changes in a rat monoarthritis model: prophylactic and therapeutic effects of meloxicam

OBJECTIVE AND DESIGN

The objective of this study was to determine the ability of meloxicam prophylaxis and therapy to blunt the effect of complete Freund's adjuvant (CFA) induced monoarthritis.

MATERIALS AND METHODS

First the validity of this animal model was established by examining joint changes at multiple levels after injecting CFA into the tibio-tarsal joint. Next, meloxicam (5 mg/kg) or vehicle was administered on days 0-7 (prophylactic) and on days 7-16 (therapeutic) in separate groups of animals.

RESULTS

The CFA-injected joint demonstrated hallmark histological and structural changes such as pannus formation, bone remodeling, cartilage erosion and immune cell infiltration. Both prophylactic and therapeutic treatment with meloxicam effectively reduced swelling (ankle circumference), oedema and extravasation of Evans blue dye in the affected joint. Moreover, meloxicam reduced loss in range of motion and also reduced mechanical stimulus evoked pain scores. Notably, these effects persisted after discontinuing drug treatment.

CONCLUSION

The present study provides a unique comparison of prophylactic versus therapeutic effects of meloxicam in the CFA-induced model of monoarthritis.

Sedative load and mortality among residents of long-term care facilities: a prospective cohort study

BACKGROUND

Older people are often prescribed multiple drugs with sedative properties. Most research has focused on specific classes of sedative and psychotropic drugs. The cumulative effect of taking multiple drugs with sedative properties has been termed 'sedative load'. Few previous studies have investigated the sedative load among residents of long-term care facilities. No previous studies have assessed the possible association between sedative load and mortality.

OBJECTIVE

The objective of this study was to describe the sedative load among residents of long-term care facilities, and to investigate a possible association between sedative load and mortality.

METHODS

This was a prospective cohort study. The study population comprised all 1444 residents of 53 long-term care wards in seven hospitals in Helsinki during September 2003. Of the eligible residents, 1087 residents or their proxies provided written informed consent to participate. Medical, medication and follow-up mortality data were available for 1004 residents. The main outcome measures were sedative load and all-cause mortality.

RESULTS

The mean age of the residents was 81.3 (SD 10.9) years, and the mean number of regularly used drugs per resident was 7.1 (SD 3.4). Fifteen percent of residents were categorized as non-users of sedative drugs, 32% as users of some drugs with sedative properties and 53% as residents with a high sedative load. There was a bivariate association between having a higher sedative load and younger age (p < 0.001), male sex (p = 0.006), not being widowed (p = 0.001), diagnosis of depression (p < 0.001), diagnosis of psychiatric illness other than depression (p < 0.001), not being diagnosed with dementia (p = 0.009) and a shorter duration of institutional care (p = 0.02). Unadjusted analysis revealed that having a higher sedative load was associated with increased survival (p = 0.04, log rank test). However, in the adjusted Cox proportional hazard model, only poor nutritional status (hazard ratio [HR] 1.55; 95% CI 1.32, 1.82), male sex (HR 1.37; 95% CI 1.12, 1.69), increasing age (HR 1.04; 95% CI 1.03, 1.05) and co-morbidity (HR 1.07; 95% CI 1.02, 1.13) were significantly associated with risk of death.

CONCLUSIONS

There is a very high rate of sedative and psychotropic drug use among residents of long-term care facilities in Helsinki. However, having a high sedative load was not associated with an increased risk of death. Further research is needed to investigate the possible association between sedative load and mortality using alternative models and methods, and in different resident populations.

Preventing the gastrointestinal adverse effects of nonsteroidal anti-inflammatory drugs: from risk factor identification to risk factor intervention

Nonsteroidal anti-inflammatory drugs (NSAIDs) have huge prescription volumes, for two main reasons: the aging of the population is increasing the prevalence of diseases that respond to NSAIDs, such as osteoarthritis; and NSAIDs are highly effective drugs that contribute crucially to the management of many diseases. In France, the number of physician orders that include an NSAID is estimated at 25 to 30 million per year. Nevertheless, the use of NSAIDs is limited by adverse effects. The gastrointestinal tract is the main target of NSAID toxicity, and NSAID therapy is among the leading causes of bleeding from upper gastrointestinal ulcers. Adverse events targeting the lower gastrointestinal tract are also of concern, although they receive less attention. To effectively prevent NSAID toxicity, it must be recognized that the risk of adverse events can be diminished but not eliminated. Therefore, the risk/benefit ratio must be carefully evaluated at each prescription. A number of risk factors should be emphasized. Thus, the risk increases with age, and there is a sharp risk increase at 60 years of age. Other risk factors include a history of ulcers (most notably with bleeding), the use of high NSAID dosages, Helicobacter pylori infection, and the concomitant use of antiplatelet agents. Minimizing NSAID-related gastrointestinal toxicity requires a careful risk factor evaluation; selection of the most appropriate NSAID and NSAID dosage; and, in some patients, prophylactic gastroprotective therapy, for instance with a proton pump inhibitor. Gastrointestinal symptoms either have no value for predicting gastrointestinal events or occur too late to serve as alarm signals. The toxicity advantages of cyclooxygenase-2 inhibitors seem modest and do not eliminate the need for this rational prescription strategy.

Uncomplicated peptic ulcer in the UK: trends from 1997 to 2005

BACKGROUND

Few studies have examined the incidence of uncomplicated peptic ulcer or the trends in factors affecting its incidence.

AIM

To estimate the incidence rate of uncomplicated peptic ulcer in the UK from 1997 to 2005 and report temporal changes in the main known preventive and risk factors.

METHODS

Population-based cohort study of 1 049 689 patients enrolled in The Health Improvement Network in the UK. We estimated the incidence rate of uncomplicated peptic ulcer and evaluated temporal trends in demographic characteristics and prescription patterns for various anti-inflammatory and gastroprotective agents.

RESULTS

Overall uncomplicated peptic ulcer incidence was 0.75 cases per 1000 persons-years, declining from 1.1 to 0.52 cases per 1000 person-years between 1997 and 2005. Distributions of age, gender and alcohol habits were similar in 1997 and 2005. The proportion of documented Helicobacter pylori-negative cases increased from 5% to 12%. Monthly prevalence of subjects with prescriptions for traditional non-aspirin NSAIDs changed from 7.7% to 6.8%, Coxibs from 0% to 0.7%, and proton pump inhibitors (PPIs) from 2.4% to 7.4%. The proportion of subjects on prescription NSAIDs on PPIs increased continuously over time.

CONCLUSION

A reduction in H. pylori-related peptic ulcers, changing patterns in NSAID use and increasing PPI use may have contributed to a decline in uncomplicated peptic ulcer incidence in the UK.

Nonsteroid anti-inflammatory drug-induced gastroduodenal injury

PURPOSE OF REVIEW

This article reviews selected publications related to nonsteroid anti-inflammatory drug (NSAID)-induced gastroduodenal toxicity in recent years.

RECENT FINDINGS

This article provides a comprehensive review of the latest evidence on the epidemiology of NSAID-induced gastroduodenal injury, recommendations on optimal gastroprotective regimens among patients in need of NSAID, risk stratification approach by considering gastrointestinal and cardiovascular risks, and negative interaction between proton pump inhibitors (PPIs) and clopidogrel.

SUMMARY

Current evidence indicates that a PPI and a cyclooxygenase (COX)-2-selective NSAID provides the best gastric protection. In light of potential cardiovascular hazard of NSAIDs, physicians should select an NSAID according to individual patients' cardiovascular risk (i.e., naproxen vs. a nonnaproxen NSAID). The choice of gastroprotective therapy depends on the number and nature of gastrointestinal risk factors. PPI co-therapy is recommended in patients with high gastrointestinal risk on aspirin. Whether there is any clinically important interaction between PPIs and clopidogrel remains uncertain.