Determinants and sequelae associated with utilization of acetaminophen versus traditional nonsteroidal antiinflammatory drugs in an elderly population

Protocol for the RETHINK study: a randomised, double-blind, parallel-group, non-inferiority clinical trial comparing acetaminophen and NSAIDs for treatment of chronic pain in elderly patients with osteoarthritis of the hip and knee

INTRODUCTION

In patients with chronic pain, oral analgesics are essential treatment options to manage pain appropriately, improve activities of daily living abilities and achieve a higher quality of life (QOL). It is desirable to select analgesics for elderly patients based on comparative data on analgesic effect and risk of adverse events; however, there are few comparative studies so far. The purpose of this study is to determine whether the efficacy and safety of acetaminophen are non-inferior to non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of chronic pain associated with osteoarthritis of the hip and knee in elderly patients.

METHODS AND ANALYSIS

This study is a multicentre, randomised controlled, double-blind, parallel-group study to compare the analgesic effect and adverse events between acetaminophen or NSAIDs (loxoprofen or celecoxib). A total of 400 elderly patients with osteoarthritis of the hip and knee will be recruited from five institutions in Japan. Patients of 65 years or older with osteoarthritis-related pain will be registered and randomly assigned to acetaminophen, loxoprofen or celecoxib with 2:1:1 allocation. The primary endpoint is change in the Brief Pain Inventory (BPI) item 3 (worst pain) score from baseline to week 8. The secondary endpoints are BPI item 3 score change from baseline to week 4, health-related QOL measured by Short Form-8 Health Survey, and occurrence of adverse events including gastrointestinal disorders and abnormal liver function. Data will be analysed in accordance with a predefined statistical analysis plan.

ETHICS AND DISSEMINATION

This study protocol was approved by the Kyushu University Hospital Certified Institutional Review Board for Clinical Trials on 28 January 2021 (KD2020004) and the chief executive of each participating hospital. The results of the study will be submitted to international peer-reviewed journals, and the main findings will be presented at international scientific conferences.

TRIAL REGISTRATION NUMBER

jRCTs071200112.

Why paracetamol (acetaminophen) is a suitable first choice for treating mild to moderate acute pain in adults with liver, kidney or cardiovascular disease, gastrointestinal disorders, asthma, or who are older

Acute pain is among the most common reasons that people consult primary care physicians, who must weigh benefits versus risks of analgesics use for each patient. Paracetamol (acetaminophen) is a first-choice analgesic for many adults with mild to moderate acute pain, is generally well tolerated at recommended doses (≤4 g/day) in healthy adults and may be preferable to non-steroidal anti-inflammatory drugs that are associated with undesirable gastrointestinal, renal, and cardiovascular effects. Although paracetamol is widely used, many patients and physicians still have questions about its suitability and dosing, especially for older people or adults with underlying comorbidities, for whom there are limited clinical data or evidence-based guidelines. Inappropriate use may increase the risks of both overdosing and inadequate analgesia. To address knowledge deficits and augment existing guidance in salient areas of uncertainty, we have researched, reviewed, and collated published evidence and expert opinion relevant to the acute use of paracetamol by adults with liver, kidney, or cardiovascular diseases, gastrointestinal disorders, asthma, or/and who are older. A concern is hepatotoxicity, but this is rare among adults who use paracetamol as directed, including people with cirrhotic liver disease. Putative epidemiologic associations of paracetamol use with kidney or cardiovascular disease, hypertension, gastrointestinal disorders, and asthma largely reflect confounding biases and are of doubtful relevance to short-term use (<14 days). Paracetamol is a suitable first-line analgesic for mild to moderate acute pain in many adults with liver, kidney or cardiovascular disease, gastrointestinal disorders, asthma, and/or who are older. No evidence supports routine dose reduction for older people. Rather, dosing for adults who are older and/or have decompensated cirrhosis, advanced kidney failure, or analgesic-induced asthma that is known to be cross-sensitive to paracetamol, should be individualized in consultation with their physician, who may recommend a lower effective dose appropriate to the circumstances.

Effect of a New Synergistic Combination of Low Doses of Acetylsalicylic Acid, Caffeine, Acetaminophen, and Chlorpheniramine in Acute Low Back Pain

The present paper continues a more complex research related to the increased synergism in terms of both anti-inflammatory and analgesic effect obtained by the addition of chlorpheniramine (CLF) to the common acetylsalicylic acid (ASA), acetaminophen (PAR), and caffeine (CAF) combination. This synergistic effect was previously highlighted both in vitro in rat models and in vivo in the treatment of migraine. The aim of the research was to further evaluate the analgesic effect of a synergistic low-dose ASA-PAR-CAF-CLF combination in the treatment of low back pain, in a parallel, multiple-dose, double-blind, active controlled clinical trial. A number of 89 patients with low back pain of at least moderate intensity were randomly assigned to receive Algopirin^® (ALG), a combinational product containing 125 mg ASA, 75 mg PAR, 15 mg CAF, and 2 mg CLF, or PAR 500 mg, a drug recognized by American Pain Society as "safe and effective" in the treatment of low back pain. One tablet of the assigned product was administered three times a day for seven consecutive days. The patients evaluated their pain level using a Visual Analog Scale prior to administration, and at 1, 2, 4, and 6 h after the morning dose. Time course of effect was similar in structure and size for both treatments. Pain relief appeared rapidly and steadily increased over 4 h after drug administration. Differential pain curves of ALG and PAR were very similar and comparable with the previously determined ALG analgesia pattern in migraine. Differences between the daily mean pain scores were not statistically significant for the two treatments. Similar results were obtained for the Sum of Pain Intensity Differences (SPID) for 0-4 h and 0-6 h intervals as well as for the time course of the proportion of patients with at least 30% and at least 50% pain relief. In conclusion, in spite of very small doses of active components, ALG proved equally effective to the standard low back pain treatment and therefore a viable therapeutic alternative, mainly for patients with gastrointestinal and hepatic sensitivity. Trial Registration: www.ClinicalTrials.gov, identifier EudraCT No.: 2015-002314-74.

Pharmacokinetics and safety of repeated oral dosing of acetaminophen in adult horses

BACKGROUND

There are no published studies on the pharmacokinetics of acetaminophen at the dosage used clinically (20 mg/kg), nor has the safety of multiple doses in horses been investigated.

OBJECTIVE

Define the pharmacokinetic parameters of oral acetaminophen at 20 mg/kg in adult horses as a single dose, and twice daily for 14 days to assess the safety of multiple dosing.

STUDY DESIGN

Pharmacokinetic study, multiple dose safety study.

METHODS

Eight healthy Thoroughbred geldings were given acetaminophen (20 mg/kg; 500 mg tablets) orally as a single dose followed by doses every 12 h for 14 days. Serial blood samples were collected for determination of plasma acetaminophen concentrations using high performance liquid chromatography with ultraviolet detection. Serum biochemical analysis, gastroscopy and liver biopsy were examined during the safety study.

RESULTS

Following a single dose, mean maximum concentration (C_max ) was 16.61 μg/mL at 1.35 h (T_max ), and drug concentration was below the lower limit of detection in most horses by 24 h. Elimination half-life (T_1/2 ) was 2.78 h. No significant accumulation was noted following multiple doses. Average C_max of acetaminophen following multiple oral dosing was 15.85 μg/mL, with a T_max of 0.99 h and T_1/2 of 4 h. Serum activities of sorbitol dehydrogenase were significantly decreased and total bilirubin concentrations were significantly increased following the last dose. No statistically significant changes were noted in gastroscopy scores.

MAIN LIMITATIONS

Only one dose level (20 mg/kg) was studied, sample size was small and only a single breed and sex was used, with no pretreatment liver biopsies.

CONCLUSION

This study described the pharmacokinetics of acetaminophen following single and multiple 20 mg/kg oral doses in adult horses and demonstrated the safety of acetaminophen with multiple oral dosing over 14 days. The summary is available in Portuguese - see Supporting information.

Paracetamol in Older People: Towards Evidence-Based Dosing?

Paracetamol is the most commonly used analgesic in older people, and is mainly dosed according to empirical dosing guidelines. However, the pharmacokinetics and thereby the effects of paracetamol can be influenced by physiological changes occurring with ageing. To investigate the steps needed to reach more evidence-based paracetamol dosing regimens in older people, we applied the concepts used in the paediatric study decision tree. A search was performed to retrieve studies on paracetamol pharmacokinetics and safety in older people (> 60 years) or studies that performed a (sub) analysis of pharmacokinetics and/or safety in older people. Of 6088 articles identified, 259 articles were retained after title and abstract screening. Further abstract and full-text screening identified 27 studies, of which 20 described pharmacokinetics and seven safety. These studies revealed no changes in absorption with ageing. A decreased (3.9-22.9%) volume of distribution (Vd) in robust older subjects and a further decreased Vd (20.3%) in frail older compared with younger subjects was apparent. Like Vd, age and frailty decreased paracetamol clearance (29-45.7 and 37.5%) compared with younger subjects. Due to limited and heterogeneous evidence, it was difficult to draw firm and meaningful conclusions on changed risk for paracetamol safety in older people. This review is a first step towards bridging knowledge gaps to move to evidence-based paracetamol dosing in older subjects. Remaining knowledge gaps are safety when using therapeutic dosages, pharmacokinetics changes in frail older people, and to what extent changes in paracetamol pharmacokinetics should lead to a change in dosage in frail and robust older people.

Status of etoricoxib in the treatment of rheumatic diseases. Expert panel opinion

Pain is one of the most disabling symptoms of rheumatoid diseases. Patients with pain secondary to osteoarthritis (OA), rheumatoid arthritis (RA), ankylosing spondylitis (AS) or gout require effective analgesic treatment, and the physician’s task is to select a drug that is best suited for an individual patient. The choice of pharmacotherapy should be based both on drug potency and clinical efficacy, and its safety profile, particularly in the elderly population, as the number of comorbidities (and hence the risk of treatment complications and drug interactions) rises with age. In cases involving a high risk of gastrointestinal complications or concerns about hepatotoxicity, with a low cardiovascular risk, the first-line nonsteroidal anti-inflammatory drugs to consider should be coxibs including etoricoxib.

Paracetamol: not as safe as we thought? A systematic literature review of observational studies

OBJECTIVES

We conducted a systematic literature review to assess the adverse event (AE) profile of paracetamol.

METHODS

We searched Medline and Embase from database inception to 1 May 2013. We screened for observational studies in English, which reported mortality, cardiovascular, gastrointestinal (GI) or renal AEs in the general adult population at standard analgesic doses of paracetamol. Study quality was assessed using Grading of Recommendations Assessment, Development and Evaluation. Pooled or adjusted summary statistics were presented for each outcome.

RESULTS

Of 1888 studies retrieved, 8 met inclusion criteria, and all were cohort studies. Comparing paracetamol use versus no use, of two studies reporting mortality one showed a dose-response and reported an increased relative rate of mortality from 0.95 (0.92 to 0.98) to 1.63 (1.58 to 1.68). Of four studies reporting cardiovascular AEs, all showed a dose-response with one reporting an increased risk ratio of all cardiovascular AEs from 1.19 (0.81 to 1.75) to 1.68 (1.10 to 2.57). One study reporting GI AEs reported a dose-response with increased relative rate of GI AEs or bleeds from 1.11 (1.04 to 1.18) to 1.49 (1.34 to 1.66). Of four studies reporting renal AEs, three reported a dose-response with one reporting an increasing OR of ≥30% decrease in estimated glomerular filtration rate from 1.40 (0.79 to 2.48) to 2.19 (1.4 to 3.43).

DISCUSSION

Given the observational nature of the data, channelling bias may have had an important impact. However, the dose-response seen for most endpoints suggests a considerable degree of paracetamol toxicity especially at the upper end of standard analgesic doses.

A perspective on the epidemiology of acetaminophen exposure and toxicity in the United States

Acetaminophen is a commonly-used analgesic in the US and, at doses of more than 4 g/day, can lead to serious hepatotoxicity. Recent FDA and CMS decisions serve to limit and monitor exposure to high-dose acetaminophen. This literature review aims to describe the exposure to and consequences of high-dose acetaminophen among chronic pain patients in the US. Each year in the US, approximately 6% of adults are prescribed acetaminophen doses of more than 4 g/day and 30,000 patients are hospitalized for acetaminophen toxicity. Up to half of acetaminophen overdoses are unintentional, largely related to opioid-acetaminophen combinations and attempts to achieve better symptom relief. Liver injury occurs in 17% of adults with unintentional acetaminophen overdose.

Valdecoxib for the management of chronic and acute pain

Cyclooxygenase-2 specific inhibitors have anti-inflammatory and analgesic properties, and are effective in managing a wide range of chronic and acute painful conditions such as adult rheumatoid arthritis, osteoarthritis, migraine, primary dysmenorrhea and postoperative pain. Valdecoxib, an orally administered cyclooxygenase-2 specific inhibitor, provides effective pain relief for both chronic and acute conditions, and reduces postoperative opioid use, with a concomitant reduction in opioid-related adverse events. Valdecoxib also has superior gastrointestinal safety compared with nonspecific nonsteroidal anti-inflammatory drugs, and at therapeutic doses, it is generally safe and well tolerated in terms of renal and cardiovascular events. This drug profile reviews the efficacy, safety and tolerability of valdecoxib for the management of chronic and acute pain.

The gastrointestinal microbiome and musculoskeletal diseases: a beneficial role for probiotics and prebiotics

Natural medicines are an attractive option for patients diagnosed with common and debilitating musculoskeletal diseases such as Osteoarthritis (OA) or Rheumatoid Arthritis (RA). The high rate of self-medication with natural products is due to (1) lack of an available cure and (2) serious adverse events associated with chronic use of pharmaceutical medications in particular non-steroidal anti-inflammatory drugs (NSAIDs) and high dose paracetamol. Pharmaceuticals to treat pain may disrupt gastrointestinal (GIT) barrier integrity inducing GIT inflammation and a state of and hyper-permeability. Probiotics and prebiotics may comprise plausible therapeutic options that can restore GIT barrier functionality and down regulate pro-inflammatory mediators by modulating the activity of, for example, Clostridia species known to induce pro-inflammatory mediators. The effect may comprise the rescue of gut barrier physiological function. A postulated requirement has been the abrogation of free radical formation by numerous natural antioxidant molecules in order to improve musculoskeletal health outcomes, this notion in our view, is in error. The production of reactive oxygen species (ROS) in different anatomical environments including the GIT by the epithelial lining and the commensal microbe cohort is a regulated process, leading to the formation of hydrogen peroxide which is now well recognized as an essential second messenger required for normal cellular homeostasis and physiological function. The GIT commensal profile that tolerates the host does so by regulating pro-inflammatory and anti-inflammatory GIT mucosal actions through the activity of ROS signaling thereby controlling the activity of pathogenic bacterial species.

Paracetamol (acetaminophen): a blessing or a hidden curse?

This Journal has recently published a splendid review of all you need to know about paracetamol (Graham et al. 2013), an analgesic widely used in the long-term management of arthritis. It clearly presents the science and hard facts. This commentary, by contrast, discusses some aspects of the metapharmacology of paracetamol; particularly by asking questions of how we might extract more benefit and suffer less adverse reactions when using this analgesic in the context of non-transient inflammation. As both a drug and a toxin, paracetamol exemplifies how beneficial and/or deleterious responses may be conditioned by circumstances (disease stress, nutritional status, fasting, etc.).

Pain management in dermatologic procedures: before and after

BACKGROUND

Periprocedural analgesic therapy is an often overlooked, but critical component of ensuring adequate surgical patient care and overall satisfaction with surgical outcomes. Adequate pain management requires thorough assessment of pain and complete knowledge and understanding of the various therapeutic agents available.

OBJECTIVES

To further the knowledge and understanding of current strategies in pain management.

METHODS

A literature review was conducted through PubMed to define current pain assessment and management strategies.

RESULTS AND CONCLUSIONS

Appropriate pain assessment leads to the selection of optimal pharmacologic options for pain control in the acute postoperative setting.

Risk of spontaneous intracranial hemorrhage in HIV-infected individuals: a population-based cohort study

BACKGROUND

We studied the association between HIV infection, antiretroviral medications, and the risk of spontaneous intracranial hemorrhage.

METHODS

We performed a cohort and nested case control study in an administrative database. We selected all HIV-positive individuals presenting between 1985 and 2007. Each HIV-positive subject was matched with 4 HIV-negative individuals. We used a Poisson regression model to calculate rates of intracranial hemorrhage according to HIV status. We conducted a case -control study nested within the cohort of HIV-positive individuals to look at the effect of antiretroviral medications. Odds ratios for antiretroviral exposure were obtained using conditional logistic regression.

RESULTS

There were 7,053 HIV-positive and 27,681 HIV-negative subjects, representing 138,704 person-years. There were 49 incident intracranial hemorrhages, 29 in HIV-positive and 20 in HIV-negative individuals. The adjusted hazard ratio for intracranial hemorrhage in HIV-positive compared to HIV-negative patients was 3.28 (95% confidence interval [CI] 1.75-6.12). The effect was reduced to 1.99 (95% CI 0.92-4.31) in the absence of AIDS-defining conditions, and increased to 7.64 (95% CI 3.78-15.43) in subjects with AIDS-defining conditions. Hepatitis C infection, illicit drug or alcohol abuse, intracranial lesions, and coagulopathy were all strongly associated with intracranial hemorrhage (all P < .001). In the case control study, 29 cases of ICH in HIV-positive individuals were matched to 228 HIV-positive controls. None of the antiretroviral classes were associated with an increase in the odds ratio of intracranial hemorrhage.

CONCLUSIONS

The risk of intracranial hemorrhage in HIV-positive individuals seems to be mostly associated with AIDS-defining conditions, other comorbidities, or lifestyle factors. No association was found between use of antiretroviral medications and intracranial hemorrhage.

Green-lipped mussel (Perna canaliculus) extract efficacy in knee osteoarthritis and improvement in gastrointestinal dysfunction: a pilot study

OBJECTIVE

Clinical data demonstrating efficacy for nutraceutical compounds marketed for the symptom relief of osteoarthritis (OA) have been largely contentious. Furthermore, no association has been linked between clinical trial inconsistencies and gastrointestinal (GI) dysfunction. The aim of this study was to primarily investigate the efficacy of a high-dose New Zealand green-lipped mussel (GLM) extract in patients diagnosed with OA of the knee and concurrently assess GLM impact on GI function.

METHODS

An open label, single group allocation study was conducted, that administered 3,000 mg/day of GLM extract over 8 weeks to 21 subjects diagnosed with knee OA. Outcome measures were scored using the WOMAC, the Lequesne algofunctional index, and the Gastrointestinal Symptom Rating Scale (GSRS) tools. An intention-to-treat analysis was employed and subject data collected at T₀, T₄ and T₈ weeks.

RESULTS

Paired t tests showed significant improvement for the Lequesne, WOMAC (p < 0.001) and GSRS (p = 0.005) scores. A repeated measures ANOVA analysis showed significant improvement in scores for the Lequesne (F = 20.317, p < 0.001), WOMAC (F = 28.383, p < 0.001) and the GSRS (F = 9.221, p = 0.002).

CONCLUSION

Green-lipped mussel significantly improved knee joint pain, stiffness and mobility. We report for the first time that the administration of GLM extract also significantly improved GI symptoms by 49% in OA patients. Given that GI dysfunction is linked to analgesic medication use, we further conclude that the therapeutic efficacy of the GLM extract used was possibly correlated to its effects on GI function by improving GSRS scores from baseline. Results from this trial highlight the requisite for further clinical investigations of gastrointestinal tract function in OA patients.

Association between HIV infection, antiretroviral therapy, and risk of acute myocardial infarction: a cohort and nested case-control study using Québec's public health insurance database

BACKGROUND

Morbidity associated with cardiovascular disease is increasing in the HIV-infected population. We aimed to study the impact of HIV and of antiretrovirals on acute myocardial infarction (AMI).

METHODS

We performed a cohort and a nested case-control study using the dataset of the Régie de l'Assurance Maladie du Québec. HIV-positive patients were identified using ICD-9 diagnostic codes and matched to HIV-negative patients. Within the HIV-positive cohort, cases of AMI were identified and matched to HIV-positive patients without AMI. The coprimary outcomes were the risk of AMI associated with HIV exposure in the cohort study and that associated with exposure to antiretrovirals in the case-control study. Data were analysed using Poisson and conditional logistic regression.

RESULTS

About 7053 HIV-positive patients were matched to 27,681 HIV-negative patients. Incidence rates of AMI in the HIV+ cohort was 3.88 95% confidence interval (CI) (3.26 to 4.58) per 1000 patient-years, compared to 2.21 95% CI (1.93 to 2.52) per 1000 patient-years in the HIV cohort. The adjusted incidence ratio of AMI for HIV-infected patients was 2.11 95%CI (1.69 to 2.63). Among HIV+ patients, 125 AMI cases were matched with 1084 HIV+ patients. We found increased odds ratio (95% CI) of AMI associated with any exposure to abacavir 1.79 (1.16 to 2.76), P = 0.02, efavirenz 1.83 (1.21 to 2.76) P = 0.004, lopinavir 1.98 (1.24 to 3.16) P = 0.004, and ritonavir 2.29 (1.48 to 3.54) P < 0.001.

CONCLUSIONS

HIV+ individuals were at higher risk of AMI than the general population, and several antiretrovirals were associated with an increased risk of AMI. Results should be interpreted with caution in absence of data on smoking and HIV clinical status.

Exposure to bisphosphonates and risk of colorectal cancer: a population-based nested case-control study

BACKGROUND

Chemoprevention is a potentially attractive strategy for decreasing the burden of colorectal cancer (CRC). Preclinical studies suggest that bisphosphonates (BPs) may have direct antitumour effects against CRC. The objective of this study was to determine the effect of exposure to BPs on the incidence of CRC.

METHODS

The Manitoba Cancer Registry was used to identify patients who were diagnosed with CRC from 2000 to 2009 who had been living in Manitoba for at least 5 years before diagnosis (cases). Each case was matched to 10 controls of similar age, sex, and duration of residence in Manitoba using incidence density sampling. Exposure to BPs was determined using the provincial Drug Program Information Network database. Conditional logistic regression analysis was performed to determine the effect of exposure to BPs on CRC incidence with adjustment for health care use, medical procedures (including lower gastrointestinal endoscopy), socioeconomic status, and pre-existing health conditions.

RESULTS

In total, 5425 patients with CRC were matched to 54,242 controls. In the multivariate analysis, exposure to BPs was associated with a reduction in the risk of CRC (2-13 BP prescriptions over ≥5 years: odds ratio [OR] 0.84; 95% confidence interval [CI], 0.71-1.00; ≥14 BP prescriptions over ≥5 years: OR, 0.78; 95% CI, 0.65-0.94). When the effect of specific BP agents was evaluated, the effect was significant only for exposure to risedronic acid (OR, 0.50; 95% CI, 0.30-0.85). There was no significant effect of increasing duration or cumulative dose of alendronic acid.

CONCLUSIONS

The results from this study suggested that exposure to BPs, especially risedronic acid, may be associated with a decreased risk of developing CRC.

Pharmacologic intervention for osteoarthritis in older adults

The management of osteoarthritis requires a careful combination of pharmacologic and nonpharmacologic therapies to effect improvements in pain and function. When choosing pharmacologic therapy, the potential toxicities must be considered relative to potential benefits. This review highlights commonly used medications and presents the evidence for their effectiveness as well as their toxicities. Acetaminophen and nonsteroidal antiinflammatory drugs are the mainstay of pharmacologic therapy, but there are numerous adjunctive or alternative medications that may provide some benefit to patients with osteoarthritis.

Long-term use of statins and risk of colorectal cancer: a population-based study

OBJECTIVES

We conducted a population-based cohort study to determine the effect of long-term regular use of statins on the risk of colorectal cancer (CRC).

METHODS

Individuals who were dispensed statins regularly were identified from Manitoba's population-based prescription drug database and followed up until diagnosis of CRC, migration out of province, death, or December 2005. The incidence of CRC in this group was compared with that among individuals who were never dispensed statins. Stratified analysis was performed to determine the risk after 5 years of regular statin use. Multivariate Poisson regression models were used to adjust for potential confounding by age, sex, and history of diabetes, inflammatory bowel disease, coronary heart disease, lower gastrointestinal endoscopy, resective colorectal surgery, use of nonsteroidal anti-inflammatory drugs, hormone replacement therapy (among women), and median household income. The dose effect was evaluated in defined daily dose units.

RESULTS

In total, 35,739 individuals were dispensed statins regularly. In all, 10,287 (49% males; 51% females) long-term (>or=5 years) regular statin users were followed up for up to 5 additional years. In multivariate analysis, the incidence rate ratio (IRR) of CRC among those dispensed statins regularly compared with those who were never dispensed statins (n=377,532) was 1.13 (95% confidence interval (CI): 1.02-1.25). The CRC risk among the long-term regular statin users was similar to that for individuals never dispensed statins (IRR, 0.89; 95% CI: 0.70-1.13). A statistically nonsignificant risk reduction was observed among high-dose long-term regular statin users.

CONCLUSIONS

These findings suggest that long-term regular use of statins for the current clinical indications does not protect against CRC. The benefit of high-dose long-term statin use needs further evaluation.

Adherence to weekly oral bisphosphonate therapy: cost of wasted drugs and fractures

In an observational cohort of patients treated with biphosphonates (BP), we observed that poor adherence to these drugs causes important expenditures in terms of avoidable fractures. Of particular interest are the amounts of money wasted by patients who did not take their BPs long enough to obtain a clinical benefit.

INTRODUCTION

A large proportion of patients initiated with oral weekly BP therapy stop their treatment within the first year. The objective of this study was to estimate the impact of the poor adherence to BPs in terms of drug wasted and avoidable fractures.

METHODS

The study was done on primary and secondary prevention cohorts from the Régie de l'assurance maladie du Québec (Québec). The concept of the "point of visual divergence" was used to determine the amount of wasted drug. The risk of fracture was estimated using Cox regression models. The hazard ratios of compliant patients (+80%) versus non compliant patients were used to estimate the number of fractures saved.

RESULTS

The cost of wasted drugs was $25.87 per patient initiated in the primary prevention cohort and $30.52 in the secondary prevention cohort. If all patients had been compliant, 110 fractures would have been avoided in the primary prevention cohort and 19 fractures in the secondary prevention cohort. The cost of these avoidable fractures per patient initiated on BP therapy was $62.95 in primary prevention cohort and $330.84 in secondary prevention cohort.

CONCLUSIONS

This study confirms that poor adherence to oral BPs leads to a significant waste of money and avoidable fractures.

Differences in persistence among different weekly oral bisphosphonate medications

SUMMARY

We evaluated the differences in persistence with weekly oral bisphosphonate therapy according to the initial drug. Persistence to weekly oral preparations remains suboptimal, particularly in patients who receive generic alendronate. Alternative solutions are needed to improve the real life effectiveness of osteoporosis therapies.

INTRODUCTION

Poor persistence is widespread with oral osteoporosis (OP) therapy. The objective of this study was to evaluate the persistence among OP patients started on weekly oral bisphosphonates (BP).

METHODS

Patients newly initiated on branded risedronate, branded alendronate, or generic alendronate once weekly were selected from the Régie de l'Assurance Maladie du Québec databases. The cohort included patients with and without a previous OP fracture. The probability and the risk factors for early discontinuation were estimated using Cox regression models.

RESULTS

The study cohort included 32,804 patients. After 1 year, a significant difference in persistence on oral BP therapy was found. The patients started on branded risedronate were 11% more likely to stop OP therapy than patients started on branded alendronate. Risk of discontinuation doubled in patients initiated with generic alendronate compared to patients started on branded alendronate. Male gender was associated with a 25% increase risk of early discontinuation. No statistical association was found between previous OP fracture and early discontinuation.

CONCLUSION

This study provides further evidence of poor persistence to newly initiated oral weekly BP therapies, particularly for the patients started on generic alendronate.

The role of analgesics and intra-articular injections in disease management

The most important goals of therapy in patients with osteoarthritis are pain management, improvement in function and disability, and, ultimately, disease modification. This review discusses the current pharmacologic regimen available to address these goals. Specific attention is paid to current trends and controversies related to pharmacologic management, including the use of oral, topical, and injectable agents.

Patterns of antibiotic use and risk of hospital admission because of Clostridium difficile infection

BACKGROUND

Previous observations have indicated that infection with Clostridium difficile occurs almost exclusively after exposure to antibiotics, but more recent observations have suggested that prior antibiotic exposure may be less frequent among cases of community-acquired disease.

METHODS

We used 2 linked health databases to perform a matched, nested case-control study of elderly patients admitted to hospital with community-acquired C. difficile infection. For each of 836 cases among people 65 years of age or older, we selected 10 controls. We determined the proportion of cases that occurred without prior antibiotic exposure and estimated the risk related to exposure to different antibiotics and the duration of increased risk.

RESULTS

Of the 836 cases, 442 (52.9%) had no exposure to antibiotics in the 45-day period before the index date, and 382 (45.7%) had no exposure in the 90-day period before the index date. Antibiotic exposure was associated with a rate ratio (RR) of 10.6 (95% confidence interval [CI] 8.9-12.8). Clindamycin (RR 31.8, 95% CI 17.6-57.6), cephalosporins (RR 14.9, 95% CI 10.9-20.3) and gatifloxacin (RR 16.7, 95% CI 8.3-33.6) were associated with the highest risk. The RR for C. difficile infection associated with antibiotic exposure declined from 15.4 (95% CI 12.2-19.3) by about 20 days after exposure to 3.2 (95% CI 2.0-5.0) after 45 days. Use of a proton pump inhibitor was associated with increased risk (RR 1.6, 95% CI 1.3-2.0), as were concurrent diagnoses of inflammatory bowel disease (RR 4.1, 95% CI 2.6-6.6), irritable bowel syndrome (RR 3.4, 95% CI 2.3-5.0) and renal failure (RR 1.7, 95% CI 1.2-2.2).

INTERPRETATION

Community-acquired C. difficile infection occurred in a substantial proportion of individuals with no recent exposure to antibiotics. Among patients who had been exposed to antibiotics, the risk declined markedly by 45 days after discontinuation of use.

New horizons and perspectives in the treatment of osteoarthritis

Osteoarthritis (OA) is increasingly prevalent worldwide and is associated with a significant economic burden. Despite the increasing number of patients with OA, treatments to manage the condition remain symptomatic, designed to control pain, and improve function and quality of life while limiting adverse events. Both the EULAR (European League Against Rheumatism) and the OARSI (Osteoarthritis Research Society International) issued new guidelines in 2007 and 2008 recommending a combination of nonpharmacological and pharmacological modalities to manage OA effectively. Because of gastrointestinal risks (including ulcer complications) and cardiovascular risks (including hypertension and thrombotic events associated with nonsteroidal anti-inflammatory drugs [NSAIDs]), these guidelines propose acetaminophen as the first choice anti-inflammatory agents. However, NSAIDs are considered to be more effective than acetaminophen for relief of pain. Given the efficacy, safety, and tolerability issues associated with NSAIDs, development of new agents to manage the pain associated with arthritis but without the cardiovascular and gastrointestinal adverse events remains a priority. This review considers current recommendations for the treatment of OA, the most recent evidence on the cardiovascular risks associated with current NSAID treatments, and the potential of newer anti-inflammatory agents with improved benefit-risk profiles.

Patterns of antibiotic use and risk of hospital admission because of Clostridium difficile infection

BACKGROUND

Previous observations have indicated that infection with Clostridium difficile occurs almost exclusively after exposure to antibiotics, but more recent observations have suggested that prior antibiotic exposure may be less frequent among cases of community-acquired disease.

METHODS

We used 2 linked health databases to perform a matched, nested case-control study of elderly patients admitted to hospital with community-acquired C. difficile infection. For each of 836 cases among people 65 years of age or older, we selected 10 controls. We determined the proportion of cases that occurred without prior antibiotic exposure and estimated the risk related to exposure to different antibiotics and the duration of increased risk.

RESULTS

Of the 836 cases, 442 (52.9%) had no exposure to antibiotics in the 45-day period before the index date, and 382 (45.7%) had no exposure in the 90-day period before the index date. Antibiotic exposure was associated with a rate ratio (RR) of 10.6 (95% confidence interval [CI] 8.9-12.8). Clindamycin (RR 31.8, 95% CI 17.6-57.6), cephalosporins (RR 14.9, 95% CI 10.9-20.3) and gatifloxacin (RR 16.7, 95% CI 8.3-33.6) were associated with the highest risk. The RR for C. difficile infection associated with antibiotic exposure declined from 15.4 (95% CI 12.2-19.3) by about 20 days after exposure to 3.2 (95% CI 2.0-5.0) after 45 days. Use of a proton pump inhibitor was associated with increased risk (RR 1.6, 95% CI 1.3-2.0), as were concurrent diagnoses of inflammatory bowel disease (RR 4.1, 95% CI 2.6-6.6), irritable bowel syndrome (RR 3.4, 95% CI 2.3-5.0) and renal failure (RR 1.7, 95% CI 1.2-2.2).

INTERPRETATION

Community-acquired C. difficile infection occurred in a substantial proportion of individuals with no recent exposure to antibiotics. Among patients who had been exposed to antibiotics, the risk declined markedly by 45 days after discontinuation of use.

Hospitalizations for upper and lower GI events associated with traditional NSAIDs and acetaminophen among the elderly in Quebec, Canada

BACKGROUND

The risk of upper/lower gastrointestinal (GI) adverse events associated with the concomitant use of traditional nonsteroidal anti-inflammatory drugs (tNSAIDs) with acetaminophen has not been assessed. Among users of these drugs, the concomitant use of proton pump inhibitors (PPIs) with tNSAIDs may reduce the risk of upper GI adverse events, but its effect on lower GI events is not clear.

OBJECTIVE

To compare the rates of GI hospitalization (ulceration, perforation, or bleeding in the upper or lower GI tract) among elderly patients taking tNSAIDs or the combination of a tNSAID and acetaminophen with and without a PPI versus those taking acetaminophen alone.

METHODS

We conducted a population-based retrospective cohort study using data obtained from the government of Quebec health insurance agency databases and the hospital discharge summary database. Patients of 65 yr of age or older who filled a prescription for acetaminophen or a tNSAID between January 1998 and December 2004 were entered in the cohort at the date of the first filled prescription from either of these medications (index date). Follow-up ended at the first date of a GI hospitalization, death, or the end of the study period.

RESULTS

The cohort included 644,183 elderly patients. These patients received 1,778,541 prescriptions for tNSAIDs (315,222, 17.7% with a PPI), 158,711 for the combination of a tNSAID and acetaminophen (40,797, 25.7% with a PPI), 1,597,725 for acetaminophen (> 3 g/day) (504,939, 31.6% with a PPI), and 3,641,140 for acetaminophen (< or = 3 g/day) (1,031,939, 28.3% with a PPI). Using Cox regression models that adjusted for time-dependent variables (aspirin, anticoagulants, and clopidogrel) and other fixed patient baseline characteristics, we found similar risks of GI hospitalizations among time periods when patients were exposed to either a tNSAID with a PPI, acetaminophen (> 3 g/day) with a PPI, or acetaminophen (< or = 3 g/day) with a PPI. The risk of GI hospitalization among users of PPIs during exposure to the combination of acetaminophen with a tNSAID was twice as high as that of the reference category, acetaminophen (< or = 3 g/day) without a PPI (hazard ratio [HR] 2.15, 95% confidence interval [CI][1.35-3.40]). Among nonusers of PPIs, the risk of GI hospitalization was 1.20 (1.03-1.40) during exposure to acetaminophen (> 3 g/day), 1.63 (1.44-1.85) during exposure to tNSAIDs, and 2.55 (1.98-3.28) during exposure to the combination of a tNSAID and acetaminophen compared with the reference category.

CONCLUSION

Among elderly patients requiring analgesic/anti-inflammatory treatment, use of the combination of a tNSAID and acetaminophen may increase the risk of GI bleeding compared with either agent alone.

Restrictive access to clopidogrel and mortality following coronary stent implantation

BACKGROUND

In Canada, access to clopidogrel is restricted by most provincial drug insurance plans in order to contain costs. Until April 2007, the Régie de l'assurance maladie du Québec (RAMQ) Prescription Drug Insurance Plan reviewed special access forms before approving reimbursement for clopidogrel prescriptions. We investigated the impact of this restrictive process on patient's filling of prescriptions and on all-cause mortality following coronary stenting.

METHODS

We analyzed prescriptions filled and all-cause mortality in the year following a percutaneous coronary intervention among patients who underwent stent implantation between January 2000 and September 2004. We obtained administrative data from the RAMQ databases. We included patients who filled at least 1 prescription for a nonrestricted cardiovascular drug after hospital discharge. We used Cox proportional models to compare mortality rates as a function of delayed or absent outpatient clopidogrel therapy.

RESULTS

Of 13,663 patients, 1571 (11.5%) did not fill any clopidogrel prescription despite filling at least 1 nonrestricted cardiovascular drug prescription after a percutaneous coronary intervention, and 1174 (8.6%) patients filled their clopidogrel prescription with a delay of at least 1 day (median delay 5 days) after filling the nonrestricted cardiovascular drug prescription. After controlling for pertinent covariables, not filling a clopidogrel prescription (hazard ratio [HR] 1.70, 95% confidence interval [CI] 1.35-2.15) and filling with a delay (HR 1.34, 95% CI 1.01-1.80) were associated with a significant increase in all-cause mortality.

INTERPRETATION

Restricted access to clopidogrel was associated with about 20% of patients either not receiving clopidogrel or receiving therapy after a delay. Delay or absence of clopidogrel therapy increased the risk of all-cause mortality after percutaneous coronary intervention with stenting.

OARSI recommendations for the management of hip and knee osteoarthritis, Part II: OARSI evidence-based, expert consensus guidelines

PURPOSE

To develop concise, patient-focussed, up to date, evidence-based, expert consensus recommendations for the management of hip and knee osteoarthritis (OA), which are adaptable and designed to assist physicians and allied health care professionals in general and specialist practise throughout the world.

METHODS

Sixteen experts from four medical disciplines (primary care, rheumatology, orthopaedics and evidence-based medicine), two continents and six countries (USA, UK, France, Netherlands, Sweden and Canada) formed the guidelines development team. A systematic review of existing guidelines for the management of hip and knee OA published between 1945 and January 2006 was undertaken using the validated appraisal of guidelines research and evaluation (AGREE) instrument. A core set of management modalities was generated based on the agreement between guidelines. Evidence before 2002 was based on a systematic review conducted by European League Against Rheumatism and evidence after 2002 was updated using MEDLINE, EMBASE, CINAHL, AMED, the Cochrane Library and HTA reports. The quality of evidence was evaluated, and where possible, effect size (ES), number needed to treat, relative risk or odds ratio and cost per quality-adjusted life years gained were estimated. Consensus recommendations were produced following a Delphi exercise and the strength of recommendation (SOR) for propositions relating to each modality was determined using a visual analogue scale.

RESULTS

Twenty-three treatment guidelines for the management of hip and knee OA were identified from the literature search, including six opinion-based, five evidence-based and 12 based on both expert opinion and research evidence. Twenty out of 51 treatment modalities addressed by these guidelines were universally recommended. ES for pain relief varied from treatment to treatment. Overall there was no statistically significant difference between non-pharmacological therapies [0.25, 95% confidence interval (CI) 0.16, 0.34] and pharmacological therapies (ES=0.39, 95% CI 0.31, 0.47). Following feedback from Osteoarthritis Research International members on the draft guidelines and six Delphi rounds consensus was reached on 25 carefully worded recommendations. Optimal management of patients with OA hip or knee requires a combination of non-pharmacological and pharmacological modalities of therapy. Recommendations cover the use of 12 non-pharmacological modalities: education and self-management, regular telephone contact, referral to a physical therapist, aerobic, muscle strengthening and water-based exercises, weight reduction, walking aids, knee braces, footwear and insoles, thermal modalities, transcutaneous electrical nerve stimulation and acupuncture. Eight recommendations cover pharmacological modalities of treatment including acetaminophen, cyclooxygenase-2 (COX-2) non-selective and selective oral non-steroidal anti-inflammatory drugs (NSAIDs), topical NSAIDs and capsaicin, intra-articular injections of corticosteroids and hyaluronates, glucosamine and/or chondroitin sulphate for symptom relief; glucosamine sulphate, chondroitin sulphate and diacerein for possible structure-modifying effects and the use of opioid analgesics for the treatment of refractory pain. There are recommendations covering five surgical modalities: total joint replacements, unicompartmental knee replacement, osteotomy and joint preserving surgical procedures; joint lavage and arthroscopic debridement in knee OA, and joint fusion as a salvage procedure when joint replacement had failed. Strengths of recommendation and 95% CIs are provided.

CONCLUSION

Twenty-five carefully worded recommendations have been generated based on a critical appraisal of existing guidelines, a systematic review of research evidence and the consensus opinions of an international, multidisciplinary group of experts. The recommendations may be adapted for use in different countries or regions according to the availability of treatment modalities and SOR for each modality of therapy. These recommendations will be revised regularly following systematic review of new research evidence as this becomes available.

Chronic neck pain: how to approach treatment

Chronic neck pain is a common patient complaint. Despite its frequency as a clinical problem, there are few evidence-based studies that document efficacy of therapies for neck pain. The treatment of this symptom is based primarily on clinical experience. Preventing the development of chronic neck pain can be achieved by modification of the work environment with chairs that encourage proper musculoskeletal movement. The use of neck supports for sleep and active neck exercises together can improve neck pain. Passive therapies, including massage, acupuncture, mechanical traction, and electrotherapy, have limited benefit when measured by clinical trial results. NSAIDs, muscle relaxants, and pure analgesics are the mainstays of therapy. Local injections of anesthetics with or without soluble corticosteroid preparations offer additional pain relief. The purpose of these agents is to diminish pain to facilitate normal neck movement. Surgical therapy with cervical spine fusion is indicated for the rare patient with intractable neck pain resistant to all nonsurgical therapies.

COX-2 selective inhibitors in the treatment of osteoarthritis

OBJECTIVES

To assess the efficacy of cyclooxygenase-2 selective inhibitors (coxibs) in osteoarthritis (OA) and their gastrointestinal, cardiovascular, renovascular, and hepatic side effects compared with traditional nonsteroidal antiinflammatory drugs (NSAIDs) and acetaminophen.

METHODS

Bibliographic database searches for randomized controlled trials, meta-analyses, and literature reviews.

RESULTS

Coxibs are comparable to traditional NSAIDs, providing moderate benefit for OA patients in pain and function versus placebo. NSAIDs, including coxibs, are superior to acetaminophen for OA, particularly in patients with moderate to severe pain. Coxibs decrease gastroduodenal ulcers (74% relative risk reduction) and ulcer complications (61% reduction) versus traditional NSAIDs. Meta-analysis of randomized trials indicates that coxibs increase the risk of myocardial infarctions approximately twofold versus placebo and versus naproxen, but do not increase the risk versus nonnaproxen NSAIDs. NSAIDs, including coxibs, commonly cause fluid retention and increase blood pressure and uncommonly induce congestive heart failure or significant renal dysfunction; risk factors include advanced age, hypertension, and heart or kidney disease. NSAIDs are a rare cause of clinical hepatotoxicity (<1 liver-related death per 100,000 NSAID users in clinical studies). Increased rates of aminotransferase elevations occur with rofecoxib (2%) and high-dose lumiracoxib (3%), and postmarketing cases of clinical liver injury with lumiracoxib have been reported recently.

CONCLUSIONS

Coxibs are as effective as traditional NSAIDs and superior to acetaminophen for the treatment of OA. Coxibs cause fewer gastrointestinal complications than traditional NSAIDs. Coxibs increase cardiovascular risk versus placebo and naproxen-but probably not versus nonnaproxen NSAIDs. Blood pressure commonly increases after initiation of selective or nonselective NSAIDs, especially in hypertensive patients.

Hospitalization for gastrointestinal adverse events attributable to the use of low-dose aspirin among patients 50 years or older also using non-steroidal anti-inflammatory drugs: a retrospective cohort study

BACKGROUND

Use of aspirin with non-steroidal anti-inflammatory drugs increases the risk of gastrointestinal ulcers; however, it is not clear if this risk varies with the non-steroidal anti-inflammatory drug used.

AIM

To assess the risk of gastrointestinal hospitalizations attributable to aspirin in patients 50 years or older also using non-steroidal anti-inflammatory drugs.

METHODS

Administrative data of patients 50 years or older who received a non-steroidal anti-inflammatory drug or acetaminophen prescription between 1998 and 2004 were used.

RESULTS

Study patients received 7,412,992 non-steroidal anti-inflammatory drug prescriptions and 5,614,044 acetaminophen prescriptions among which 23% and 32%, respectively, were dispensed to aspirin users. Time-dependent Cox regression models revealed that, compared to patients using acetaminophen (without aspirin), the adjusted hazard ratio (95% CI) among non-users of aspirin were: rofecoxib 1.3 (1.2, 1.5), celecoxib 0.7 (0.6, 0.8), diclofenac 1.5 (1.2, 1.7), ibuprofen 0.9 (0.6, 1.4), naproxen 2.5 (2.1, 3.0) and piroxicam 1.5 (0.8, 2.8); among users of aspirin: rofecoxib 3.2 (2.8, 3.7), celecoxib 1.8 (1.5, 2.1), diclofenac 2.8 (2.2, 3.5), ibuprofen 1.4 (0.8, 2.7), naproxen 2.2 (1.6, 3.0) and piroxicam 2.0 (0.8, 5.4). The risk attributable to aspirin varied from none with naproxen to 61% (53%, 68%) with celecoxib.

CONCLUSION

The increase in gastrointestinal hospitalization attributable to aspirin differed with the non-steroidal anti-inflammatory drug used, and seemed higher with cyclo-oxygenase-2 inhibitors than with non-selective non-steroidal anti-inflammatory drugs.

Acetaminophen (paracetamol) is a selective cyclooxygenase-2 inhibitor in man

For more than three decades, acetaminophen (INN, paracetamol) has been claimed to be devoid of significant inhibition of peripheral prostanoids. Meanwhile, attempts to explain its action by inhibition of a central cyclooxygenase (COX)-3 have been rejected. The fact that acetaminophen acts functionally as a selective COX-2 inhibitor led us to investigate the hypothesis of whether it works via preferential COX-2 blockade. Ex vivo COX inhibition and pharmacokinetics of acetaminophen were assessed in 5 volunteers receiving single 1000 mg doses orally. Coagulation-induced thromboxane B(2) and lipopolysaccharide-induced prostaglandin E(2) were measured ex vivo and in vitro in human whole blood as indices of COX-1 and COX-2 activity. In vitro, acetaminophen elicited a 4.4-fold selectivity toward COX-2 inhibition (IC(50)=113.7 micromol/L for COX-1; IC(50)=25.8 micromol/L for COX-2). Following oral administration of the drug, maximal ex vivo inhibitions were 56% (COX-1) and 83% (COX-2). Acetaminophen plasma concentrations remained above the in vitro IC(50) for COX-2 for at least 5 h postadministration. Ex vivo IC(50) values (COX-1: 105.2 micromol/L; COX-2: 26.3 micromol/L) of acetaminophen compared favorably with its in vitro IC(50) values. In contrast to previous concepts, acetaminophen inhibited COX-2 by more than 80%, i.e., to a degree comparable to nonsteroidal antiinflammatory drugs (NSAIDs) and selective COX-2 inhibitors. However, a >95% COX-1 blockade relevant for suppression of platelet function was not achieved. Our data may explain acetaminophen's analgesic and antiinflammatory action as well as its superior overall gastrointestinal safety profile compared with NSAIDs. In view of its substantial COX-2 inhibition, recently defined cardiovascular warnings for use of COX-2 inhibitors should also be considered for acetaminophen.

Association between nonnaproxen NSAIDs, COX-2 inhibitors and hospitalization for acute myocardial infarction among the elderly: a retrospective cohort study

PURPOSE

To evaluate the association between rofecoxib, celecoxib, diclofenac, and ibuprofen and the risk of hospitalization for acute myocardial infarction (AMI) in an elderly population.

METHODS

We conducted a retrospective cohort study, using data from the government of Quebec health insurance agency databases, among patients 65-80 years of age who filled a prescription for any of the study drugs during 1999-2002. Cox regression models with time-dependent exposure were used to compare the incidence rates of hospitalization for AMI adjusting for patients' baseline characteristics. Analyses stratified by dose and number of supplied days were also conducted.

RESULTS

At the index date, a total of 91 062 patients were taking rofecoxib, 127 928 celecoxib, 49 193 diclofenac, and 15 601 ibuprofen. The adjusted hazard ratio (HR) (95%CI) of hospitalization for AMI were: celecoxib versus rofecoxib: 0.90 (0.79, 1.01); ibuprofen versus rofecoxib: 0.95 (0.65, 1.37); diclofenac versus rofecoxib: 1.01 (0.84, 1.22). In secondary analyses based on intended duration of use, neither COX-2 selective inhibitor was associated with a higher risk than ibuprofen or diclofenac. The unadjusted risk of AMI for all NSAIDs increased with dose. In the direct two way adjusted comparison of each NSAID stratified by dose, the only statistically significant difference was with rofecoxib >25 mg/day versus celecoxib >200 mg/day.

CONCLUSION

In this study there was no difference between AMI occurrence in elderly patients taking rofecoxib or celecoxib at recommended doses for chronic indications versus those taking ibuprofen/diclofenac. However, the risk of AMI was higher among patients using higher doses of rofecoxib (>25 mg/day) compared to patients using higher doses of celecoxib (>200 mg/day).

Aceclofenac vs paracetamol in the management of symptomatic osteoarthritis of the knee: a double-blind 6-week randomized controlled trial

OBJECTIVE

To evaluate the efficacy and tolerability of aceclofenac, 200 mg/day, and paracetamol, 3000 mg/day, in the treatment of osteoarthritis (OA) of the knee.

METHODS

This was a double-blind, parallel-group, multicentre clinical trial involving patients with symptomatic OA of the knee, conducted in Spain. Patients were randomly allocated to aceclofenac 100 mg twice daily (n=82) or paracetamol 1000 mg three times daily (n=86). Patients were assessed at baseline and 6 weeks. Primary efficacy measures were severity of pain (visual analogue scale, VAS), Lequesne OA knee index, and patient's and physician's global assessment of disease activity. Severity of knee pain at rest or walking, stiffness, knee swelling and tenderness, and assessment of health-related quality of life (Health Assessment Questionnaire, Western Ontario and McMaster Universities Osteoarthritis Index, and Short Form 36) were included as secondary endpoints.

RESULTS

Both treatment groups showed significant improvement compared with their baseline values in the four primary endpoints. Mean between-treatment differences favoured aceclofenac over paracetamol on pain (VAS, 7.64 mm [95% confidence interval (CI), 0.44-14.85 mm]), Lequesne OA index (1.41 [95% CI, 0.45-2.36]), and patient's (0.33 [95% CI, 0.06-0.61]) and physician's (0.23 [95% CI, 0.01-0.47]) global assessments. Adverse events were similar for both drugs (paracetamol, 29% patients vs aceclofenac, 32%; P=0.71). Four patients withdrew in each group due to adverse events. Patients tended to prefer aceclofenac to paracetamol (P=0.001), and more treated with paracetamol withdrew from the study due to lack of efficacy (n=8 vs n=1, P=0.035, for paracetamol and aceclofenac, respectively).

CONCLUSION

At 6 weeks, patients with symptomatic OA of the knee showed a greater improvement in pain and functional capacity with aceclofenac than paracetamol with no difference in tolerability.

Do proton-pump inhibitors confer additional gastrointestinal protection in patients given celecoxib?

OBJECTIVE

Celecoxib has a superior upper-gastrointestinal (GI) safety profile compared with nonselective nonsteroidal antiinflammatory drugs (NS-NSAIDs). It is unclear whether the utilization of a proton-pump inhibitor (PPI) with celecoxib confers additional protection in elderly patients. We assessed the association between GI hospitalizations and use of celecoxib with a PPI versus celecoxib alone, and NS-NSAIDs with a PPI or NS-NSAIDs alone in elderly patients.

METHODS

We conducted a population-based retrospective cohort study using the government of Quebec health services administrative databases. Elderly patients were included at their first dispensing date for celecoxib or an NS-NSAID between April 1999 and December 2002. Prescriptions were separated into 4 groups: celecoxib, celecoxib plus PPI, NS-NSAIDs, and NS-NSAIDs plus PPI. Cox regression models with time-dependent exposure were used to compare the hazard rates of GI hospitalization between the 4 groups adjusting for patient characteristics at baseline.

RESULTS

There were 1,161,508 prescriptions for celecoxib, 360,799 for celecoxib plus PPI, 715,176 for NS-NSAIDs, and 148,470 for NS-NSAIDs plus PPI. The adjusted hazard ratios (HRs; 95% confidence intervals [95% CIs]) were 0.69 (0.52-0.93) for celecoxib plus PPI versus celecoxib, 0.98 (0.67-1.45) for NS-NSAIDs plus PPI versus celecoxib, and 2.18 (1.82-2.61) for NS-NSAIDs versus celecoxib. Subgroup analyses showed that use of a PPI with celecoxib may be beneficial in patients ages >/=75 years but was not better than celecoxib alone among those ages 66-74 years (HR 0.98, 95% CI 0.63-1.52).

CONCLUSION

Addition of a PPI to celecoxib conferred extra protection for patients ages >/=75 years. PPI did not seem necessary with celecoxib for patients ages 66-74 years.

Medical management of cervical spondylosis

Medical management is often the initial management of cervical spondylitic syndromes, including radiculopathy, myelopathy, and neck pain. This includes pharmacological and rehabilitation treatment. Prospective studies comparing the efficacy of surgical versus medical management are lacking. The indications and efficacy of pharmacological and rehabilitative treatments are reviewed. The use of anti-inflammatory drugs, muscle relaxants, analgesics, antidepressants, anticonvulsants, steroids, facet joint ablation, and physical therapy are reviewed. A rationale for the medical management of acute neck pain, chronic neck pain, radiculopathy, and myelopathy is presented.

Upper gastrointestinal complications among users of paracetamol

Non-steroidal anti-inflammatory drugs (NSAIDs) have been associated with upper gastrointestinal complications such as bleeding or perforation. Paracetamol has been traditionally considered a safer alternative to NSAIDs. In a previous case-control study we found that paracetamol at high doses increased the risk of upper gastrointestinal complications. We proposed to review all studies addressing the association between paracetamol and upper gastrointestinal complications and placed our results in the context of existing literature. We conducted a nested case-control study using the United Kingdom General Practice Research Database during the period between April 1993 and October 1998. Then we performed a systematic review of the literature indexed in MEDLINE published between 1980 and 2004. We identified a total of twelve studies that assessed the association between paracetamol and upper gastrointestinal complications. We used a fixed effects model to calculate a summary estimate of these studies. In the nested case control study, use of paracetamol was associated with a small elevated risk of upper gastrointestinal complications (relative risk (RR), 1.3; 95% confidence interval (CI), 1.1-1.5). The RR was 3.6 (95% CI, 2.6-5.1) among paracetamol users of more than 2 g daily, whereas smaller doses did not increase the risk. Among the twelve studies identified in the systematic review, estimates ranged from 0.2 through 2.0 with a summary estimate of 1.3 (95% CI, 1.2-1.5). Our findings indicate that use of paracetamol at the doses most commonly used confer little or no increased risk of upper gastrointestinal complications. More data are needed to confirm or refute the suggestion that high-dose paracetamol is associated with an increased risk of upper gastrointestinal complications of the same magnitude as the one observed with traditional NSAIDs.

A review of the application of propensity score methods yielded increasing use, advantages in specific settings, but not substantially different estimates compared with conventional multivariable methods

OBJECTIVE

Propensity score (PS) analyses attempt to control for confounding in nonexperimental studies by adjusting for the likelihood that a given patient is exposed. Such analyses have been proposed to address confounding by indication, but there is little empirical evidence that they achieve better control than conventional multivariate outcome modeling.

STUDY DESIGN AND METHODS

Using PubMed and Science Citation Index, we assessed the use of propensity scores over time and critically evaluated studies published through 2003.

RESULTS

Use of propensity scores increased from a total of 8 reports before 1998 to 71 in 2003. Most of the 177 published studies abstracted assessed medications (N=60) or surgical interventions (N=51), mainly in cardiology and cardiac surgery (N=90). Whether PS methods or conventional outcome models were used to control for confounding had little effect on results in those studies in which such comparison was possible. Only 9 of 69 studies (13%) had an effect estimate that differed by more than 20% from that obtained with a conventional outcome model in all PS analyses presented.

CONCLUSIONS

Publication of results based on propensity score methods has increased dramatically, but there is little evidence that these methods yield substantially different estimates compared with conventional multivariable methods.

Acetaminophen, like conventional NSAIDs, may reduce synovitis in osteoarthritic knees

OBJECTIVE

To determine the extent to which treatment of patients with symptomatic knee osteoarthritis (OA) with non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen (ACET) reduces total effusion volume and synovial tissue volume, as quantified by magnetic resonance imaging (MRI).

METHODS

Sequential pilot studies used subjects whose knee OA was treated with NSAIDs (n=10) or with ACET <or=4 g/day (n=20), respectively. After a five half-lives washout of their pain medication, the OA knee with the higher pain score >or=15 of 25 on the Western Ontario and McMaster Universities' pain scale underwent l.5T MRI. Effusion was quantified in axial short tau inversion recovery images; to measure synovial tissue volume, fat-suppressed T1-weighted axial images were obtained 3 min after i.v. injection of gadolinium contrast. After the initial MRI examination, patients resumed their customary pain medications until the severity of knee pain returned to baseline, when pain was again measured and the MRI was repeated.

RESULTS

Pain severity after washout was similar in subjects taking ACET and NSAIDs. Reinstitution of ACET resulted in a 50% decrease in the mean of pain scores (P=1.7 x 10(-12)) that was comparable with that seen after the reinstitution of NSAID (49%, P=6.0 x 10(-7)). The mean total effusion volume measured during the flare of knee pain induced by the withdrawal of the two drugs was comparable (ACET 16.9 ml, NSAID 16.2 ml; P=0.884). Significant decreases in mean total effusion volume were observed after reinstitution of both ACET (-4.5 ml, P=0.009) and NSAID (-3.3 ml, P=0.013); the difference between drugs was not significant. Analyses of synovial volume yielded similar results.

CONCLUSION

While uncontrolled and derived from small samples, these data suggest that ACET may have a significant anti-inflammatory effect in patients with knee OA, comparable with that achieved with NSAIDs, possibly through an effect on neurogenic inflammation. Joint pain is the clinical feature of OA that most often leads the affected individual to seek medical attention. Because many patients with OA improve symptomatically with the use of NSAIDs, it has been widely assumed that the pain of OA is due to synovial inflammation. However, the origins of OA pain are numerous and may vary from patient to patient and, within the same subject, from visit to visit. Although the articular cartilage is usually the site of the most obvious pathological changes in this disease, it is aneural and, therefore, is not the source of joint pain. However, in addition to the synovium, the subchondral bone, joint capsule, osteophytes, menisci, ligaments, periarticular tendons, entheses and bursae all contain nociceptive nerve endings, stimulation of which by chemical or physical mediators may be a basis for OA pain.

EULAR evidence based recommendations for the management of hip osteoarthritis: report of a task force of the EULAR Standing Committee for International Clinical Studies Including Therapeutics (ESCISIT)

OBJECTIVE

To develop evidence based recommendations for the management of hip osteoarthritis (OA).

METHODS

The multidisciplinary guideline development group comprised 18 rheumatologists, 4 orthopaedic surgeons, and 1 epidemiologist, representing 14 European countries. Each participant contributed up to 10 propositions describing key clinical aspects of hip OA management. Ten final recommendations were agreed using a Delphi consensus approach. Medline, Embase, CINAHL, Cochrane Library, and HTA reports were searched systematically to obtain research evidence for each proposition. Where possible, outcome data for efficacy, adverse effects, and cost effectiveness were abstracted. Effect size, rate ratio, number needed to treat, and incremental cost effectiveness ratio were calculated. The quality of evidence was categorised according to the evidence hierarchy. The strength of recommendation was assessed using the traditional A-D grading scale and a visual analogue scale.

RESULTS

Ten key treatment propositions were generated through three Delphi rounds. They included 21 interventions, such as paracetamol, NSAIDs, symptomatic slow acting disease modifying drugs, opioids, intra-articular steroids, non-pharmacological treatment, total hip replacement, osteotomy, and two general propositions. 461 studies were identified from the literature search for the proposed interventions of efficacy, side effects, and cost effectiveness. Research evidence supported 15 interventions in the treatment of hip OA. Evidence specific for the hip was strikingly lacking. Strength of recommendation varied according to category of research evidence and expert opinion.

CONCLUSION

Ten key recommendations for the treatment of hip OA were developed based on research evidence and expert consensus. The effectiveness and cost effectiveness of these recommendations were evaluated and the strength of recommendation was scored.

Multimodal Analgesia Techniques and Postoperative Rehabilitation

The concept of multimodal analgesia involves the use of different classes of analgesics and different sites of analgesic administration to provide superior dynamic pain relief with reduced analgesic-related side effects. Although multimodal analgesia techniques have assumed increasing importance in the management of perioperative pain, it has become increasingly apparent that postoperative outcome may not be improved. Nevertheless, the integration of multimodal analgesia techniques with a multimodal and multidisciplinary rehabilitation program may enhance recovery, reduce hospital stay, and facilitate early convalescence.

Treatment costs to prevent or treat upper gastrointestinal adverse events associated with NSAIDs

The widespread use of nonselective NSAIDs and cyclo-oxygenase (COX)-2 inhibitors has a substantial impact on healthcare budgets worldwide. The cost of their gastrointestinal (GI) adverse effects is a major component of their direct cost and has received much attention in the literature. Published studies have often differed in their methodologies and results. It is important for decision makers to understand the reasons for these differences in order to make informed decisions. We conducted a literature review to summarise data that evaluate the direct costs of NSAID-related GI adverse effects worldwide. This resulted in 789 articles from which 29 studies met the inclusion criteria and were fully reviewed. Of these 29, the 9 studies that assessed the cost of COX-2 inhibitors were all based on decision economic models, compared with only 7 of the remaining 20 studies, which assessed the cost of nonselective NSAIDs. In most studies, the perspective was that of the healthcare payer and the costs assessed were reimbursement costs. Costs of GI events almost doubled between regular users and non-users of nonselective NSAIDs and were much higher in high-dose versus low-dose users. The ratio of the total cost of nonselective NSAIDs to their acquisition cost reported in all studies varied from 1.36 to 2.12. Both of these numbers were reported in one single study assessing several different NSAIDs in France. Thus, the GI adverse events attributable to nonselective NSAIDs are substantial, and their costs often exceed the cost of the nonselective NSAID itself.The acquisition cost of the COX-2 inhibitors was the main driver of their total cost. The GI adverse effects with the COX-2 inhibitors added 10-20% to their acquisition cost in North America, while this increase was about 50% in some European countries. Decision analysis models showed that the direct costs of COX-2 inhibitors were lower than those of nonselective NSAIDs in patients at risk of NSAID gastropathy but higher in patients at no to low risk of gastropathy. Thus, from an economic perspective, the healthcare system would benefit from treating patients at risk of NSAID gastropathy with COX-2 inhibitors, but not those at no to low risk.

Symptomatic treatment of osteoarthritis: paracetamol or NSAIDs?

The clinical management of osteoarthritis (OA) is today symptomatic, its main goals being relief of pain and improvement of function. Therapy should be multimodal and composed of non-pharmacological, pharmacological and, if necessary, surgical procedures. Paracetamol and non-steroidal anti-inflammatory drugs (NSAIDs) are evidence-based drugs for the symptomatic relief of OA. Newly published comparative studies have shown that NSAIDs are more effective than paracetamol--in contrast to studies from the early 1990s. Some studies have documented that more severe pain and the presence of inflammation can predict better response from NSAIDs than from paracetamol; on the other hand other studies have not confirmed this. Patient preference studies have shown that patients favour NSAIDs, but up to 40% consider paracetamol at least as effective as NSAIDs. With regard to efficacy, safety and cost, the majority of new guidelines recommend paracetamol as a first-choice analgesic for patients with OA of the knee or hip, and the use of NSAIDs only in cases of inadequate effect of paracetamol and especially in the presence of inflammation. There is much evidence that OA is a phasic disease and it may be that NSAIDs are useful during identifiable periods of inflammatory activity and can be avoided at other times. The concept of the short-term use of NSAIDs during flares and the use of a simple analgesic in the long term seems to be the best variant for the majority of patients with optimal benefit/risk and cost-effectiveness.