Prevention of complicated ulcer disease among chronic users of nonsteroidal anti-inflammatory drugs: the use of a nomogram in cost-effectiveness analysis

Identification of the Optimal Model for the Prediction of Diabetic Retinopathy in Chinese Rural Population: Handan Eye Study

BACKGROUND

To identify an optimal model for diabetic retinopathy (DR) prediction in Chinese rural population by establishing and comparing different algorithms based on the data from Handan Eye Study (HES).

METHODS

Five algorithms, including multivariable logistic regression (MLR), classification and regression trees (C&RT), support vector machine (SVM), random forests (RF), and gradient boosting machine (GBM), were used to establish DR prediction models with HES data. The performance of the models was assessed based on the adjusted area under the ROC curve (AUROC), sensitivity, specificity, and accuracy.

RESULTS

The data on 4752 subjects were used to build the DR prediction model, and among them, 198 patients were diagnosed with DR. The age of the included subjects ranged from 30 to 85 years old, with an average age of 50.9 years (SD = 3.04). The kappa coefficient of the diagnosis between the two ophthalmologists was 0.857. The MLR model revealed that blood glucose, systolic blood pressure, and body mass index were independently associated with the development of DR. The AUROC obtained by GBM (0.952), RF (0.949), and MLR (0.936) was similar and statistically larger than that of CART (0.682) and SVM (0.765).

CONCLUSIONS

The MLR model exhibited excellent prediction performance and visible equation and thus was the optimal model for DR prediction. Therefore, the MLR model may have the potential to serve as a complementary screening tool for the early detection of DR, especially in remote and underserved areas.

Nanofibers used for the delivery of analgesics

Nanofibers are extremely advantageous for drug delivery because of their high surface area-to-volume ratios, high porosities and 3D open porous structures. Local delivery of analgesics by using nanofibers allows site-specificity and requires a lower overall drug dosage with lower adverse side effects. Different analgesics have been loaded onto various nanofibers, including those that are natural, synthetic and copolymer, for various medical applications. Analgesics can also be singly or coaxially loaded onto nanofibers to enhance clinical applications. In particular, analgesic-eluting nanofibers provide additional benefits to preventing wound adhesion and scar formation. This paper reviews current research and breakthrough discoveries on the innovative application of analgesic-loaded nanofibers that will alter the clinical therapy of pain.

Cost-effectiveness analyses of osteoarthritis oral therapies: a systematic review

BACKGROUND

Cost-effectiveness analyses (CEAs) have been performed for oral non-disease-altering osteoarthritis (OA) treatments for well over a decade. During that period the methods for performing these analyses have evolved as pharmacoeconomic methods have advanced, new treatments have been introduced, and the knowledge of associated adverse events (AEs) has improved.

OBJECTIVE

The objective of this systematic review was to trace the development of CEAs for oral non-disease-altering treatments in OA.

METHODS

A systematic search for CEAs of OA oral treatments was performed of the English-language medical literature using the following databases: PubMed, EMBASE, MEDLINE In-Process, EconLit, and Cochrane. Key requirements for inclusion were that the population described patients with OA or arthritis and that the analysis reported at least one incremental cost-effectiveness ratio. Each identified publication was assessed for inclusion. Thirteen characteristics and all AEs appearing in each included CEA were extracted and organized. Reference lists from these CEAs were also searched. A chronology of key CEAs in the field was compiled, noting the characteristics that advanced the state of the art in modeling oral OA treatments.

RESULTS

Thirty publications of 28 CEAs were identified and evaluated. Developments in CEAs included an expanded set of comparators that broadened from non-steroidal anti-inflammatory drugs (NSAIDs) only to NSAIDs plus gastroprotective agents, cyclooxygenase-2 inhibitors, and opioids. In turn, AEs expanded from gastrointestinal (GI) events to also include cardiovascular (CV) and neurological events. Efficacy, which initially was presumed to be equivalent for all treatments, evolved to treatment-specific efficacies. Decision-tree analyses were generally replaced by Markov models or, occasionally, stochastic or discrete event simulation. Finally, outcomes have progressed from GI-centric measures to also include quality-adjusted life-years.

CONCLUSION

Methods used by CEAs of oral non-disease-altering OA treatments have evolved in response to changing treatments with different safety profiles and efficacies as well as technical advances in the application of decision science to health care.

Cost-utility analysis of duloxetine in osteoarthritis: a US private payer perspective

BACKGROUND

Duloxetine has recently been approved in the USA for chronic musculoskeletal pain, including osteoarthritis and chronic low back pain. The cost effectiveness of duloxetine in osteoarthritis has not previously been assessed. Duloxetine is targeted as post first-line (after acetaminophen) treatment of moderate to severe pain.

OBJECTIVE

The objective of this study was to estimate the cost effectiveness of duloxetine in the treatment of osteoarthritis from a US private payer perspective compared with other post first-line oral treatments, including nonsteroidal anti-inflammatory drugs (NSAIDs), and both strong and weak opioids.

METHODS

A cost-utility analysis was performed using a discrete-state, time-dependent semi-Markov model based on the National Institute for Health and Clinical Excellence (NICE) model documented in its 2008 osteoarthritis guidelines. The model was extended for opioids by adding titration, discontinuation and additional adverse events (AEs). A life-long time horizon was adopted to capture the full consequences of NSAID-induced AEs. Fourteen health states comprised the structure of the model: treatment without persistent AE, six during-AE states, six post-AE states and death. Treatment-specific utilities were calculated using the transfer-to-utility method and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total scores from a meta-analysis of osteoarthritis clinical trials of 12 weeks and longer. Costs for 2011 were estimated using Red Book, The Agency for Healthcare Research and Quality's Healthcare Cost and Utilization Project database, the literature and, sparingly, expert opinion. One-way and probabilistic sensitivity analyses were undertaken, as well as subgroup analyses of patients over 65 years old and a population at greater risk of NSAID-related AEs.

RESULTS

In the base case the model estimated naproxen to be the lowest total-cost treatment, tapentadol the highest cost, and duloxetine the most effective after considering AEs. Duloxetine accumulated 0.027 discounted quality-adjusted life-years (QALYs) more than naproxen and 0.013 more than oxycodone. Celecoxib was dominated by naproxen, tramadol was subject to extended dominance, and strong opioids were dominated by duloxetine. The model estimated an incremental cost-effectiveness ratio (ICER) of US$47,678 per QALY for duloxetine versus naproxen. One-way sensitivity analysis identified the probabilities of NSAID-related cardiovascular AEs as the inputs to which the ICER was most sensitive when duloxetine was compared with an NSAID. When compared with a strong opioid, duloxetine dominated the opioid under nearly all sensitivity analysis scenarios. When compared with tramadol, the ICER was most sensitive to the costs of duloxetine and tramadol. In subgroup analysis, the cost per QALY for duloxetine versus naproxen fell to US$24,125 for patients over 65 years and to US$18,472 for a population at high risk of cardiovascular and gastrointestinal AEs.

CONCLUSION

The model estimated that duloxetine was potentially cost effective in the base-case population and more cost effective for subgroups over 65 years or at high risk of NSAID-related AEs. In sensitivity analysis, duloxetine dominated all strong opioids in nearly all scenarios.

Economic outcomes for celecoxib: a systematic review of pharmacoeconomic studies

Osteoarthritis and rheumatoid arthritis are conditions that are associated with significant clinical burden, and impact on patients' functional status and quality of life. Medical costs related to treating these common and disabling conditions place an economic strain on healthcare systems. This systematic review was conducted to investigate the impact of celecoxib on healthcare costs for patients with rheumatoid arthritis and osteoarthritis. In total, 24 studies examined economic outcomes associated with celecoxib in patients with these conditions. Six of these studies evaluated economic outcomes in developing regions, including Mexico, Asia and Turkey. Across all geographies, most studies were cost-effectiveness analyses comparing celecoxib with nonselective NSAIDs alone or in combination with gastroprotective agents. Overall, based on local standards, economic models indicated favorable cost-effectiveness profiles for celecoxib compared with nonselective NSAIDs and other active-treatment options. Cost analyses indicated that the use of celecoxib resulted in lower direct medical costs.

Reduced hospitalization cost for upper gastrointestinal events that occur among elderly veterans who are gastroprotected

BACKGROUND & AIMS

Despite prescription of gastroprotection among elderly nonsteroidal anti-inflammatory drug (NSAID) users, residual bleeding can still occur. We sought to determine the effect of proton pump inhibitors (PPI) on hospitalization and resource use among veterans in whom an upper gastrointestinal event (UGIE) occurred.

METHODS

We identified from national pharmacy records veterans > or =65 years prescribed an NSAID, cyclooxygenase-2 selective NSAID (coxib), or salicylate (>325 mg/day) at any Veterans Affairs (VA) facility (01/01/00-12/31/04). Prescription fill data were linked longitudinally to a Veterans Affairs-Medicare dataset of inpatient, outpatient, and death files, and demographic and provider data. Among veterans in whom a UGIE occurred, we assessed the effect of prescription strategy on hospitalization, using a multivariate logistic regression model.

RESULTS

A total of 3566 UGIEs occurred among a cohort that was predominantly male (97.5%), white (77%), with a mean age of 73.5 (SD, 5.7). Hospitalization occurred in 47.5%, and gastroprotection was associated with a 30% reduction in hospitalization compared with no PPI. Five-year pharmacy costs associated with the PPI strategy exceeded the no-PPI strategy ($742,406 vs $184,282); however, a substantial reduction in medical costs was observed with PPI ($9,948,738 vs $18,686,081).

CONCLUSIONS

Even if an NSAID-UGIE occurs in the PPI-protected older veteran, the reduction in need for hospitalization results in a cost saving to the Department of Veterans Affairs.

A comparison of cost effectiveness using data from randomized trials or actual clinical practice: selective cox-2 inhibitors as an example

BACKGROUND

Data on absolute risks of outcomes and patterns of drug use in cost-effectiveness analyses are often based on randomised clinical trials (RCTs). The objective of this study was to evaluate the external validity of published cost-effectiveness studies by comparing the data used in these studies (typically based on RCTs) to observational data from actual clinical practice. Selective Cox-2 inhibitors (coxibs) were used as an example.

METHODS AND FINDINGS

The UK General Practice Research Database (GPRD) was used to estimate the exposure characteristics and individual probabilities of upper gastrointestinal (GI) events during current exposure to nonsteroidal anti-inflammatory drugs (NSAIDs) or coxibs. A basic cost-effectiveness model was developed evaluating two alternative strategies: prescription of a conventional NSAID or coxib. Outcomes included upper GI events as recorded in GPRD and hospitalisation for upper GI events recorded in the national registry of hospitalisations (Hospital Episode Statistics) linked to GPRD. Prescription costs were based on the prescribed number of tables as recorded in GPRD and the 2006 cost data from the British National Formulary. The study population included over 1 million patients prescribed conventional NSAIDs or coxibs. Only a minority of patients used the drugs long-term and daily (34.5% of conventional NSAIDs and 44.2% of coxibs), whereas coxib RCTs required daily use for at least 6-9 months. The mean cost of preventing one upper GI event as recorded in GPRD was US$104k (ranging from US$64k with long-term daily use to US$182k with intermittent use) and US$298k for hospitalizations. The mean costs (for GPRD events) over calendar time were US$58k during 1990-1993 and US$174k during 2002-2005. Using RCT data rather than GPRD data for event probabilities, the mean cost was US$16k with the VIGOR RCT and US$20k with the CLASS RCT.

CONCLUSIONS

The published cost-effectiveness analyses of coxibs lacked external validity, did not represent patients in actual clinical practice, and should not have been used to inform prescribing policies. External validity should be an explicit requirement for cost-effectiveness analyses.

NSAIDs and the gastrointestinal tract

NSAIDs incur significant gastrointestinal (GI) side effects. The complication risk increases with history of peptic ulcer or older age. Helicobacter pylori infection and cardioprotective aspirin have independent and additive risks in the presence of NSAID use. NSAID enteropathy is increasingly recognized. Cardiovascular and GI risk stratification and H. pylori infection testing should be done before initiating NSAIDs. An NSAID combined with a proton pump inhibitor (PPI) is comparable to cyclooxygenase (COX)-2 inhibitors for gastroprotection, but for high-risk patients, COX-2 plus PPI should be considered. Aspirin and COX-2 inhibitors are associated with reduced colon adenoma risk, but higher dose and longer duration of treatment with aspirin appears effective. Hence, patients at high risk of colorectal cancer (with significant family or personal history of premalignant adenoma) must be identified, and cardiovascular and GI risk must be assessed before using these agents as chemopreventive drugs.

Perforated peptic ulcer: different ethnic, climatic and fasting risk factors for morbidity in Al-ain medical district, United Arab Emirates

AIM

To evaluate risk factors, morbidity and mortality rates of perforated peptic ulcer (PPU) and to investigate factors affecting postoperative complications of PPU.

BACKGROUND

The incidence of PPU has remained constant, simple closure with omental patch repair being the mainstay of treatment.

PATIENTS AND METHODS

One hundred and nineteen patients admitted to Al-Ain Hospital with PPU between January 2000 and March 2004 was studied retrospectively; two with deficient data were excluded from the analysis. Logistic regression was used to define factors affecting postoperative complications.

RESULTS

The mean age of patients was 35.3 years (range, 20-65). 45.7% of patients were Bangladeshi, and 85.3% originated from the Indian subcontinent. One patient, subsequently found to have a perforated gastric cancer, died. In 116 patients, 26 complications were recorded in 20 patients (17.2%). Common risk factors for perforation were smoking, history of peptic ulcer disease (PUD) and use of non-steroidal anti-inflammatory drugs (NSAIDs). A significantly increased risk of perforation was evident during the daytime fasting month of Ramadan. An increase in the acute physiology and chronic health evaluation (APACHE) II score (p = 0.047) and a reduced white blood cell count (0.04) were highly significant for the prediction of postoperative complications.

CONCLUSION

Patients with dyspeptic symptoms and a history of previous PUD should be considered for prophylactic treatment to prevent ulcer recurrence during prolonged daytime fasting in Ramadan, especially during the winter time.

Economic evaluation of nonsteroidal anti-inflammatory drug strategies in rheumatoid arthritis

Objectives:Although disease modifying antirheumatic drugs (DMARDs) are the first choice drugs in the treatment of rheumatoid arthritis, many patients still take nonsteroidal anti-inflammatory drugs (NSAIDs) as well. These drugs may cause serious gastric adverse events with continuous usage. Cyclooxygenase-2 (COX2) inhibitors were supposed to have a gastrointestinal (GI) friendly side effect profile. The aim of the study is to compare three therapeutic strategies: conventional NSAIDs, NSAID in combination with proton pump inhibitors (PPIs), and the selective COX2 inhibitor therapy (celecoxib).

Methods:A decision tree model was developed, for 1 year, to simulate cohorts within the three arms (NSAIDs, NSAID + PPI, celecoxib). The efficacy of the different active agents of NSAIDs in therapeutically relevant doses was assumed to be the same, consequently differences can be seen in the side effect profile of the drugs. Medical costs, the costs of the side effects (GI, cardiovascular [CV] events), and quality-adjusted life-years (QALYs) were calculated to gain an incremental cost-effectiveness ratio (ICER). Evaluations were made from a third party payer's perspective. We performed one-way deterministic sensitivity analyses; the results were displayed in tornado diagrams.

Results:Our model indicates that NSAID + PPI offers extra health gain for extra costs compared with conventional NSAIDs (ICER:14,287 euro/QALY), while it dominates celecoxib because of celecoxib's higher costs and lower effectiveness. According to the sensitivity analyses, QALYs had the highest influence on ICER.

Conclusions:Although COX2 inhibitors have elevated GI efficacy compared with NSAIDs, celecoxib seems to be an adequate choice only for a limited group of patients with specific conditions because of the significantly higher price and CV risk profile.

A randomized, multicentre, double-blind, parallel-group study to assess the adverse event-related discontinuation rate with celecoxib and diclofenac in elderly patients with osteoarthritis

OBJECTIVE

To compare the adverse event (AE)-related discontinuation rate with celecoxib vs. diclofenac when given to reduce joint pain associated with knee or hip osteoarthritis (OA) in elderly patients.

METHODS

This was a double-blind, randomized, multicentre, parallel-group, 1-year comparison of celecoxib 200 mg once daily and diclofenac 50 mg twice daily in 925 patients with OA aged > or = 60 years. Study visits were at baseline and at 4, 13, 26, 39, and 52 weeks. At each visit, the Patient's and Physician's Global Assessment of Arthritis (PaGAA, PhGAA), the Patient's Assessment of Arthritis Pain--Visual Analogue Scale (PAAP-VAS), and AEs were assessed. A concomitant health economic analysis was conducted throughout.

RESULTS

The rate of study discontinuation due to AEs, laboratory abnormalities, and deaths was 27% for celecoxib and 31% for diclofenac (p = 0.22). The results of the arthritis/pain efficacy assessments were similar for celecoxib and diclofenac. Significantly fewer patients in the celecoxib group than the diclofenac group experienced cardiovascular/renal AEs (70/458 vs. 95/458, p = 0.039) or hepatic AEs (10/458 vs. 39/458, p<0.0001). Medication costs were higher for celecoxib than diclofenac but mean total treatment cost was slightly higher in the diclofenac group.

CONCLUSION

Treatment with celecoxib 200 mg once daily and diclofenac 50 mg twice daily resulted in similar rates of AE-related study discontinuation in elderly patients with OA. Celecoxib and diclofenac demonstrated comparable efficacy in relieving the signs and symptoms of OA. However, the proportion of patients with cardiorenal and hepatic AEs was significantly lower in the celecoxib group than the diclofenac group.

Canadian consensus guidelines on long-term nonsteroidal anti-inflammatory drug therapy and the need for gastroprotection: benefits versus risks

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used, but are not without risks.

AIM

To provide evidence-based management recommendations to help clinicians determine optimal long-term NSAID therapy and the need for gastroprotective strategies based on an assessment of both gastrointestinal (GI) and cardiovascular (CV) risks.

METHODS

A multidisciplinary group of 21 voting participants revised and voted on the statements and the strength of evidence (assessed according to GRADE) at a consensus meeting.

RESULTS

An algorithmic approach was developed to help manage patients who require long-term NSAID therapy. The use of low-dose acetylsalicylic acid in patients with high CV risk was assumed. For patients at low GI and CV risk, a traditional NSAID alone may be acceptable. For patients with low GI risk and high CV risk, full-dose naproxen may have a lower potential for CV risk than other NSAIDs. In patients with high GI and low CV risk, a COX-2 inhibitor plus a proton pump inhibitor (PPI) may offer the best GI safety profile. When both GI and CV risks are high and NSAID therapy is absolutely necessary, risk should be prioritized. If the primary concern is GI risk, a COX-2 inhibitor plus a PPI is recommended; if CV risk, naproxen 500 mg b.d. plus a PPI would be preferred. NSAIDs should be used at the lowest effective dose for the shortest possible duration.

CONCLUSION

More large, long-term trials that examine clinical outcomes of complicated and symptomatic upper and lower GI ulcers are needed.

Incremental cost effectiveness of proton pump inhibitors for the prevention of non-steroidal anti-inflammatory drug ulcers: a pharmacoeconomic analysis linked to a case-control study

INTRODUCTION

We estimated the cost effectiveness of concomitant proton pump inhibitors (PPIs) in relation to the occurrence of non-steroidal anti-inflammatory drug (NSAID) ulcer complications.

METHODS

This study was linked to a nested case-control study. Patients with NSAID ulcer complications were compared with matched controls. Only direct medical costs were reported. For the calculation of the incremental cost effectiveness ratio we extrapolated the data to 1,000 patients using concomitant PPIs and 1,000 patients not using PPIs for 1 year. Sensitivity analysis was performed by 'worst case' and 'best case' scenarios in which the 95% confidence interval (CI) of the odds ratio (OR) and the 95% CI of the cost estimate of a NSAID ulcer complication were varied. Costs of PPIs was varied separately.

RESULTS

In all, 104 incident cases and 284 matched controls were identified from a cohort of 51,903 NSAID users with 10,402 NSAID exposition years. Use of PPIs was associated with an adjusted OR of 0.33 (95% CI 0.17 to 0.67; p = 0.002) for NSAID ulcer complications. In the extrapolation the estimated number of NSAID ulcer complications was 13.8 for non-PPI users and 3.6 for PPI users. The incremental total costs were euro 50,094 higher for concomitant PPIs use. The incremental cost effectiveness ratio was euro 4,907 per NSAID ulcer complication prevented when using the least costly PPIs.

CONCLUSIONS

Concomitant use of PPIs for the prevention of NSAID ulcer complications costs euro 4,907 per NSAID ulcer complication prevented when using the least costly PPIs. The price of PPIs highly influenced the robustness of the results.

An economic model of long-term use of celecoxib in patients with osteoarthritis

Background

Previous evaluations of the cost-effectiveness of the cyclooxygenase-2 selective inhibitor celecoxib (Celebrex, Pfizer Inc, USA) have produced conflicting results. The recent controversy over the cardiovascular (CV) risks of rofecoxib and other coxibs has renewed interest in the economic profile of celecoxib, the only coxib now available in the United States. The objective of our study was to evaluate the long-term cost-effectiveness of celecoxib compared with nonselective nonsteroidal anti-inflammatory drugs (nsNSAIDs) in a population of 60-year-old osteoarthritis (OA) patients with average risks of upper gastrointestinal (UGI) complications who require chronic daily NSAID therapy.

Methods

We used decision analysis based on data from the literature to evaluate cost-effectiveness from a modified societal perspective over patients' lifetimes, with outcomes expressed as incremental costs per quality-adjusted life-year (QALY) gained. Sensitivity tests were performed to evaluate the impacts of advancing age, CV thromboembolic event risk, different analytic horizons and alternate treatment strategies after UGI adverse events.

Results

Our main findings were: 1) the base model incremental cost-effectiveness ratio (ICER) for celecoxib versus nsNSAIDs was $31,097 per QALY; 2) the ICER per QALY was $19,309 for a model in which UGI ulcer and ulcer complication event risks increased with advancing age; 3) the ICER per QALY was $17,120 in sensitivity analyses combining serious CV thromboembolic event (myocardial infarction, stroke, CV death) risks with base model assumptions.

Conclusion

Our model suggests that chronic celecoxib is cost-effective versus nsNSAIDs in a population of 60-year-old OA patients with average risks of UGI events.

Valdecoxib is associated with improved dyspepsia-related health compared with nonspecific NSAIDs in patients with osteoarthritis or rheumatoid arthritis

OBJECTIVES

Dyspepsia and related gastrointestinal (GI) symptoms are commonly reported by patients taking nonspecific nonsteroidal anti-inflammatory drugs (NSAIDs) and significantly impact treatment effectiveness, cost, and quality of life. This study sought to evaluate dyspepsia-related health in osteoarthritis (OA) and rheumatoid arthritis (RA) patients taking valdecoxib compared with patients taking nonspecific NSAIDs.

METHODS

Analysis of two separate, double-blind, placebo-controlled studies: one in RA patients randomized to placebo, valdecoxib (10 and 20 mg once daily [o.d.]) and naproxen (500 mg twice daily [b.i.d.]); one in OA patients randomized to placebo, valdecoxib (10 and 20 mg o.d.), diclofenac (75 mg b.i.d.), or ibuprofen (800 mg three times daily [t.i.d.]). Study population comprised patients with RA in flare or clinically documented OA who required chronic symptomatic treatment with NSAIDs/analgesics. Dyspepsia-related health was evaluated at baseline and weeks 2, 6, and 12 (or early termination) using the validated Severity of Dyspepsia Assessment (SODA) questionnaire. This patient self-report tool consists of scales for evaluating dyspepsia pain intensity, nonpain symptoms, and satisfaction. Analysis was based on the intent-to-treat population with the last observation carried forward.

RESULTS

Valdecoxib was significantly better at endpoint than standard doses of naproxen, diclofenac, and ibuprofen for pain intensity scores (p < 0.05), and provided significantly improved nonpain symptom and satisfaction scores compared with naproxen for patients with RA (p < 0.05). For RA patients, the difference between valdecoxib and naproxen pain intensity scores were clinically meaningful; at all the time points, significantly fewer patients receiving valdecoxib reported severe dyspepsia pain intensity increases (>/=10 points) than those receiving naproxen. At 12 wk, fewer patients receiving valdecoxib reported severe dyspepsia pain intensity increases versus those receiving ibuprofen and diclofenac.

CONCLUSIONS

The GI tolerability of valdecoxib is superior to that of nonspecific NSAIDs, and therefore can potentially have a favorable impact on patient quality of life.

Minimizing complications from nonsteroidal antiinflammatory drugs: Cost-effectiveness of competing strategies in varying risk groups

OBJECTIVE

To appraise the cost-effectiveness of competing therapeutic strategies in patient cohorts eligible for aspirin prophylaxis with varying degrees of gastrointestinal (GI) and cardiovascular risk.

METHODS

Cost-effectiveness and cost-utility analyses were performed to evaluate 3 competing strategies for the management of chronic arthritis: 1) a generic nonselective nonsteroidal antiinflammatory drug (NSAID(NS)) alone; 2) NSAID(NS) plus a proton pump inhibitor (PPI); and 3) a cyclooxygenase 2-selective inhibitor (coxib) alone. Cost estimates were from a third-party payer perspective. The outcomes were incremental cost per ulcer complication avoided and incremental cost per quality-adjusted life year (QALY) gained. Sensitivity analysis was performed to evaluate the impact of varying patient GI risks and aspirin use.

RESULTS

In average-risk patients, the NSAID(NS) + PPI strategy costs an incremental 45,350 US dollars per additional ulcer complication avoided and 309,666 US dollars per QALY gained compared with the NSAID(NS) strategy. The coxib strategy was less effective and more expensive than the NSAID(NS) + PPI strategy. Sensitivity analysis revealed that the NSAID(NS) + PPI strategy became the dominant approach in patients at high risk for an NSAID adverse event (i.e., patients taking aspirin with > or =1 risk factor for a GI complication).

CONCLUSION

Generic nonselective NSAIDs are most cost-effective in patients at low risk for an adverse event. However, the addition of a PPI to a nonselective NSAID may be the preferred strategy in patients taking aspirin or otherwise at high risk for a GI or cardiovascular adverse event.

Assessing the cost-effectiveness of COX-2 specific inhibitors for arthritis in the Veterans Health Administration

OBJECTIVE

This study was designed to assess the cost-effectiveness of cyclooxygenase-2 specific (COX-2) inhibitors (rofecoxib and celecoxib) over nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) in high-risk arthritis patients from the perspective of the Veterans Health Administration (VA).

METHODS

This literature-based economic analysis (with data summarized from MEDLINE-indexed and other published sources, FDA reports, and data on file at VA San Diego Healthcare System) compared rofecoxib and celecoxib to NSAIDS in two arthritis patient populations considered at higher risk of developing clinically significant upper gastrointestinal events (CSUGIEs): (1) patients of any age with previous medical history of perforation/ulcer/bleed (PUB); and (2) patients 65 years and older (regardless of history of PUB). Two outcome measures were reported: (1) incremental cost per CSUGIE averted over 1 year; and (2) incremental cost per quality-adjusted life-year (QALY) gained, considering both the mortality and morbidity associated with gastrointestinal (including CSUGIEs) and cardiovascular-related adverse events. When possible, costs were modeled to reflect the VA perspective. Sensitivity analyses were conducted to test the robustness of the analysis.

RESULTS

Compared to NSAIDS, rofecoxib and celecoxib increased costs but reduced the incidence of CSUGIE. Cost per CSUGIE avoided were $7476 and $16,379 (in patients with a PUB history) and $14,294 and $18,376 (in patients aged > or = 65 years) for celecoxib and rofecoxib, respectively. In both populations, celecoxib was associated with a cost per QALY less than $50,000. In contrast, rofecoxib was found to cost more and result in a net QALY loss, due in particular to the increase in the risk of cardiovascular complications, and was therefore considered cost-ineffective. Results were most dependent on assumptions about the incidence of cardiovascular events and CSUGIE and the COX-2 inhibitors' acquisition price.

CONCLUSIONS

This analysis suggests that COX-2 inhibitors may be cost-effective from the perspective of the VA. However, cost-effectiveness appears to depend less on the specific characteristics of the high-risk target population considered but more on the agent evaluated. Celecoxib appears to be an alternative to traditional NSAIDs in the patient populations studied.

Reducing Clinically Significant Gastrointestinal Toxicity Associated with Nonsteroidal Antiinflammatory Drugs

OBJECTIVE:

To evaluate the efficacy of treatment strategies to reduce clinically significant gastrointestinal adverse effects associated with nonsteroidal antiinflammatory drugs (NSAIDs).

DATA SOURCES:

A MEDLINE search (1966–November 2003) was performed to identify relevant articles. Key search terms included proton-pump inhibitors, histamine H2 antagonists, misoprostol, cyclooxygenase-2 (COX-2) selective inhibitors, nonsteroidal antiinflammatory agents, stomach ulcer, prevention, and economics. Additional references were obtained from cross-referencing the bibliographies of selected articles.

STUDY SELECTION AND DATA EXTRACTION:

All information obtained from the MEDLINE search was reviewed. To provide the most clinically relevant information, only randomized controlled trials are included in this review.

DATA SYNTHESIS:

Clinically significant upper gastrointestinal adverse events, such as ulcers and ulcer complications, associated with NSAIDs are a cause of significant morbidity and mortality in the US. Interest in strategies to reduce the risk of these adverse events is high among clinicians and patients. Misoprostol, high-dose H2-receptor antagonists, proton-pump inhibitors, and COX-2 inhibitors have been shown to reduce this risk. Misoprostol and proton-pump inhibitors are more effective than H2-receptor antagonists; dose-related diarrhea limits the clinical utility of misoprostol. These strategies may not provide enough protection in patients taking concomitant low-dose aspirin therapy or patients with a history of ulcer complications.

CONCLUSIONS:

COX-2 inhibitors and proton-pump inhibitors are effective and well-tolerated therapies to reduce clinically significant upper gastrointestinal adverse events associated with NSAIDs.

Utilization of nonsteroidal anti-inflammatory drugs and antisecretory agents: a managed care claims analysis

PURPOSE

To describe patients initiating nonsteroidal anti-inflammatory drug (NSAID) therapy with regard to gastrointestinal and cardiac risks and patterns of antisecretory agent use, and to explore the relation between therapy type and subsequent outcomes.

METHODS

We studied patients aged 18 years or older who had continuous coverage from 1998 to 2001 and who had initiated treatment with cyclooxygenase-2 (COX-2) selective inhibitors or nonselective NSAIDs. Patients were categorized with respect to gastrointestinal and cardiac risk profiles. Proton pump inhibitor use within 15 days of initiating NSAID therapy was considered prophylactic. Logistic regression analysis was used to evaluate associations between treatment and hospitalization events, cardiac events, and health care costs.

RESULTS

We identified 106,564 eligible NSAID initiators: 65.2% used COX-2 inhibitors and 34.8% used traditional NSAIDs. Users of COX-2 inhibitors were more likely to be at higher risk of gastrointestinal bleeding and cardiac events than were NSAID users. Proton pump inhibitor prophylaxis was most common among users of COX-2 inhibitors, but was only 11% in patients at high risk of gastrointestinal bleeding. There were no differences among treatment groups in terms of gastrointestinal or cardiac events. Initiation of COX-2 inhibitor therapy was associated with greater total health care costs.

CONCLUSION

Although we found that COX-2 inhibitors were used more frequently than were traditional NSAIDs in certain groups of patients with varying cardiac or gastrointestinal risk, we did not find that their use resulted in reductions in clinical events, cotherapy with proton pump inhibitors, or costs, suggesting that a better understanding of the relation between NSAID treatment strategies and outcomes in patients with differing risk characteristics is needed.

Review article: prevention of non-steroidal anti-inflammatory drug gastrointestinal complications--review and recommendations based on risk assessment

The incidence of non-steroidal anti-inflammatory drug-related ulcer complications remains high despite the availability of potent anti-ulcer drugs and selective cyclo-oxygenase-2 inhibitors. Non-steroidal anti-inflammatory drug-related ulcer complications can be minimized by prospective assessment of patients' baseline risk, rational choice and use of non-steroidal anti-inflammatory drugs, and selective use of co-therapy strategies with gastroprotectives. Current recommendations regarding strategies using anti-ulcer drugs and cyclo-oxygenase-2 inhibitors for prevention of clinical non-steroidal anti-inflammatory drug upper gastrointestinal events are largely derived from studies using surrogates such as endoscopic ulcers, erosions, and symptoms in low- to average-risk patients. Conclusions based on surrogate and potentially manipulatable end-points are increasingly suspect with regard to applicability to clinical situations. This article reviews the risks associated with non-steroidal anti-inflammatory drugs including aspirin and includes the effect of the patients' baseline risk, and the confounding effects of Helicobacter pylori infection. In addition, uncertainties regarding the clinical efficacy of anti-ulcer drugs and cyclo-oxygenase-2 inhibitors against non-steroidal anti-inflammatory drug-related ulcer complications are put into perspective. We propose management strategies based on the risk category: low risk (absence of risk factors) (least ulcerogenic non-steroidal anti-inflammatory drug at lowest effective dose), moderate risk (one to two risk factors) (as above, plus an antisecretory agent or misoprostol or a cyclo-oxygenase-2 inhibitor), high risk (multiple risk factors or patients using concomitant low-dose aspirin, steroids, or anticoagulants) (cyclo-oxygenase-2 inhibitor alone with steroids, plus misoprostol with warfarin, or plus a proton pump inhibitors or misoprostol with aspirin), and very high risk (history of ulcer complications) (avoid all non-steroidal anti-inflammatory drugs, if possible or a cyclo-oxygenase-2 plus a proton pump inhibitors and/or misoprostol). The presence of H. pylori infection increases the risk of upper gastrointestinal complications in non-steroidal anti-inflammatory drug users by two- to fourfold suggesting that all patients requiring regular non-steroidal anti-inflammatory drug therapy be tested for H. pylori.

Classification and regression tree analysis in public health: methodological review and comparison with logistic regression

BACKGROUND

Audience segmentation strategies are of increasing interest to public health professionals who wish to identify easily defined, mutually exclusive population subgroups whose members share similar characteristics that help determine participation in a health-related behavior as a basis for targeted interventions. Classification and regression tree (C&RT) analysis is a nonparametric decision tree methodology that has the ability to efficiently segment populations into meaningful subgroups. However, it is not commonly used in public health.

PURPOSE

This study provides a methodological overview of C&RT analysis for persons unfamiliar with the procedure.

METHODS AND RESULTS

An example of a C&RT analysis is provided and interpretation of results is discussed. Results are validated with those obtained from a logistic regression model that was created to replicate the C&RT findings. Results obtained from the example C&RT analysis are also compared to those obtained from a common approach to logistic regression, the stepwise selection procedure. Issues to consider when deciding whether to use C&RT are discussed, and situations in which C&RT may and may not be beneficial are described.

CONCLUSIONS

C&RT is a promising research tool for the identification of at-risk populations in public health research and outreach.

Inadequate prevention of NSAID-induced gastrointestinal events

BACKGROUND

Use of nonsteroidal antiinflammatory drugs (NSAIDs) is a well-known cause of gastrointestinal (GI) adverse events. To protect patients at risk, several strategies are advised, including concomitant treatment with proton-pump inhibitors or switching to cyclooxygenase (COX)-2 selective NSAIDs. It is as yet unknown how many patients at risk for NSAID-induced events are protected.

OBJECTIVE

To estimate the number of patients using GI preventive treatment while at risk for NSAID-induced GI events.

METHODS

Records of patients using NSAIDs consecutively for at least 100 days (from 2001 to 2002) were obtained from the PHARMO system in the Netherlands (N = 1,000,000). GI preventive treatments were classified as adequate or inadequate based on evidence-based criteria. Adequate treatment was defined as concomitant use of misoprostol (>400 microg daily), histamine2-antagonists (> or =2 times recommended dose) or proton-pump inhibitors (> or =1 recommended dose), or alternative treatment with COX-2 selective inhibitors.

RESULTS

A total of 10,121 patients met the study inclusion criteria; 70% were women. One or more preventive strategies were prescribed in 4340 patients (42.9%), of which 2799 (64.5%) were adequate and 1541 (35.5%) inadequate. Prescribing of adequate preventive treatments increased with the number of risk factors, from 13.3% among those with no additional risk factors to 61.9% for those with > or =4 risk factors.

CONCLUSIONS

Although risk factors for GI damage were recognized, a large number of patients in the Netherlands were not or were inadequately protected against potential NSAID-associated GI damage. Despite recommendations, and even in the presence of > or =4 risk factors, almost 40% of these patients were not prescribed adequate GI preventive treatment.

Assessment of the safety of selective cyclo-oxygenase-2 inhibitors: where are we in 2003?

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used drugs worldwide despite their well-documented adverse gastrointestinal (GI) effects. The risk of developing a severe GI event varies from patient to patient and NSAID to NSAID. Selective cyclo-oxygenase-2 inhibitors (coxibs) have been designed to have similar efficacy but less GI toxicity than traditional NSAIDs, and have been shown to have an improved GI tolerability and less adverse events across a range of different GI safety assessments. In clinical trials, particularly VIGOR and CLASS, rofecoxib and celecoxib, respectively, significantly reduce the risk of ulcers and ulcer complications than nonselective NSAID comparators with ulcer rates comparable to placebo. The real benefit of a coxib comes from the sparing of the thromboxane and hence preservation of normal platelet function. Thus, there is less risk of bleeding with selective inhibition of COX-2, which is the most common and serious complication of non-selective NSAIDs. Moreover, bleeding can occur anywhere in the GI tract. Although some concern has been raised about the cardiovascular safety of coxibs, when used in recommended doses, there is no convincing evidence that patients treated with a coxib have an increased risk of cardiovascular thrombotic events. Different approaches have been advocated to minimize NSAID-related GI toxicity. Choice of less harmful NSAIDs such as coxib has been one of the strategies promoted in guidelines. The introduction of coxibs with a higher benefit-risk ratio has dramatically changed the therapeutic scenario for anti-inflammatory treatment in the clinical practice.

Iron deficiency anemia in the elderly: prevalence and endoscopic evaluation of the gastrointestinal tract in outpatients

Iron deficiency anemia (IDA), mostly due to chronic occult bleeding from the gastrointestinal tract, is a common problem in the elderly. This study aimed to determine the prevalence of IDA in the elderly and to investigate the gastrointestinal tract in elderly patients with IDA. 1,388 patients over 65 years were prospectively evaluated for IDA in our outpatient clinic. IDA was defined if decreased hemoglobin concentrations (<13 g/dl for men and <12 g/dl for women) were associated with low serum ferritin levels (<15 ng/ml in men and <9 ng/ml in women). We evaluated the gastrointestinal system of all patients with IDA by upper gastrointestinal endoscopy and colonoscopy regardless of fecal occult blood loss. The prevalence of anemia was found to be 25% (n = 347) in our study population, and 30.5% (n = 106) of these patients with anemia had iron deficiency. Upper gastrointestinal endoscopy and colonoscopy were performed in 96 patients with IDA. Fifty-eight upper gastrointestinal system lesions (55 patients, 57.3%) and 27 colonic lesions (26 patients, 27.1%) were detected. We diagnosed gastrointestinal malignancy in 15 (15.6%) elderly patients with IDA (8 colon, 1 esophageal and 6 gastric cancers). IDA is a common problem in elderly patients; consequently, before iron replacement therapy, patients should be thoroughly investigated regarding a possible association with gastrointestinal malignancy.