Propoxyphene and the risk of out-of-hospital death

Cardiovascular Complications of Opioid Use: JACC State-of-the-Art Review

Opioids are the most potent of all analgesics. Although traditionally used solely for acute self-limited conditions and palliation of severe cancer-associated pain, a movement to promote subjective pain (scale, 0 to 10) to the status of a "fifth vital sign" bolstered widespread prescribing for chronic, noncancer pain. This, coupled with rising misuse, initiated a surge in unintentional deaths, increased drug-associated acute coronary syndrome, and endocarditis. In response, the American College of Cardiology issued a call to action for cardiovascular care teams. Opioid toxicity is primarily mediated via potent μ-receptor agonism resulting in ventilatory depression. However, both overdose and opioid withdrawal can trigger major adverse cardiovascular events resulting from hemodynamic, vascular, and proarrhythmic/electrophysiological consequences. Although natural opioid analogues are devoid of repolarization effects, synthetic agents may be proarrhythmic. This perspective explores cardiovascular consequences of opioids, the contributions of off-target electrophysiologic properties to mortality, and provides practical safety recommendations.

Effect of the market withdrawal of dextropropoxyphene on use of other prescribed analgesics

Background and aims Dextropropoxyphene (DXP) is a synthetic opioid that was prescribed worldwide for mild to moderate pain. It was withdrawn from the European market in 2009. In this study we aim to investigate the effect of the market withdrawal of dextropropoxyphene in Norway on overall use of opioids and other analgesics at an individual level. Methods Data were collected from the nationwide Norwegian Prescription Database (NorPD). It covers all prescription of drugs from 01 January 2004 from Norwegian pharmacies dispensed to individuals outside institutions. The study period was divided in two 2-year periods from 01 September 2008 to 31 August 2010, and from the market withdrawal of DXP on 01 September 2010 to 31 August 2012. We included every individual that filled at least one prescription of dextropropoxyphene in the first 2-year period in our study population. In this study dextropropoxyphene, codeine and tramadol are defined as "weak opioids", and all other opioids are termed "strong opioids". Results Nine thousand one hundred and seventy-one individuals were included in our study population. Four thousand two hundred and ninety filled a prescription of DXP only once and were classified as "single users", 2,990 were users with prescriptions of up to 200 defined daily doses (DDD) over the first 2-year period, or "sporadic users", and 1,886 were classified high users with over 200 DDDs over a 2-year period. After the market withdrawal 8,392 continued to be prescribed analgesics or benzodiazepines. In the single user group, the proportion of users of weak opioids decreased from 69.5% to 57.6%, whereas the proportion of users of strong opioids was unchanged. Among the sporadic user group, the proportion of users of weak opioids went from 69.7% to 71.0%, the proportion using tramadol from 39.1% to 43.9%, and the users of strong opioids from 25.8% to 31.3%. In the high user group, there was an increase in the number of users of strong opioids from 37.8% to 51.4%. The amount of strong opioids prescribed in the high user group increased from a mean of 262.5 DDD to a mean of 398.3 DDD in the following 2 years. The amount of tramadol increased in all groups and was 3 times as high in the high user group after market withdrawal of DXP. Conclusions Our study showed that the withdrawal of DXP lead to an increase in prescription of other analgesics. The proportion of users increased in all three groups and so did the prescribed amount of other analgesics. Both the proportion of users of other opioids and the amount prescribed increased considerably. However, 1 in 10 earlier users of DXP stopped using prescribed analgesics altogether in the following 2 years. The increase in use among earlier high users of DXP was most striking. Implications This study documents markedly increased prescriptions of other opioids after withdrawal of dextropropoxyphene due to its high risk of serious complications. However, consequences of the increased use of opioids among earlier high users of DXP such as changes in risk of poisonings, accidental deaths and suicides remain to be investigated.

Analgesic consumption evolution at the emergency department of a university hospital (2006-2017): a defined daily doses based analysis

OBJECTIVE

Pain management in the emergency department (ED) is a key issue that must be regularly evaluated. Practice evaluation gold standard remains patient file analysis, but is highly time consuming. The aim of this study is to evaluate the interest of a defined daily dose (DDD) based analysis in the evaluation of pain management in the ED.

METHODS

A local indicator was elaborated based on the DDD concept: the defined dose per admission (DDA). Unlike the DDD that corresponds to a standardised total dose administered over a day, the DDA represents the average total dose administrated to a patient throughout the stay in the ED. A DDA was assigned to every analgesic, from step 1 to step 3. Oral and injectable forms were studied, but transdermal forms were not considered. DDA values were assimilated to the existing DDDs when these were officially established by the WHO. When values were not defined by the WHO, mean values observed in local practice were selected. Annual numbers of patients admitted to the ED and quantities of each analgesic supplied by the pharmacy ward were annually extracted from respective data files. Paediatric patients being treated at a specific separate ED, only adults were considered throughout the study. Raw quantities of analgesics used each year were converted to their equivalent amounts in DDA, and then expressed in numbers of DDA per 100 admissions (DDA/100A). This indicator allowed us to describe relative evolutions of analgesics prescriptions from 2006 to 2017.

RESULTS

Analgesic overall use rose from 18.4 to 30.2 DDA/100A between 2006 and 2017, representing a prescription increase of 64%. Throughout the study, step 1 analgesics rose from 10.8 to 19.3 DDA/100A (+79%), step 3 from 1.8 to 5.4 (+200%) and step 2 remained stable around 5.6 DDA/100A. The integration of orodispersible paracetamol tablets in 2013 allowed us to halve the consumption of injectable paracetamol in the long term and had no effect on classic paracetamol oral forms such as tablets or capsules. Tramadol increased from 41% to 78% among step 2 analgesics after the withdrawal of dextropropoxyphene in 2011. Codeine use shows a steady decline from 1.9 DDA/100A in 2011 to 0.72 in 2017.

DISCUSSION/CONCLUSION

The DDA concept appears to be an effective tool for assessing long-term analgesic-use trends at hospital EDs. This tool can also mitigate one major bias at EDs, that is the lack of traceability of analgesic administration in emergency contexts. This tool could be adjusted by integrating the average length of stay in the ED.

What are the therapeutic alternatives to dextropropoxyphene in France? A prescribers' survey

About a year after dextropropoxyphene (DXP) withdrawal from the French market, we conducted a survey among members of the French Society of Anesthesia & Intensive Care Medicine (Sfar) and of the French Society of the Study and Treatment of Pain (SFETD) to identify the indications for which this WHO level II analgesic had been prescribed, the prescriber's feedback following withdrawal, and the substitutive analgesics prescribed. DXP had been prescribed by more than 75% of the 430 anaesthesiologists and 230 pain specialists interviewed, mainly for acute and chronic non-cancer pain of moderate intensity. While two thirds of pain specialists were not satisfied with DXP withdrawal, this decision did not affect the majority of anaesthesiologists. In both groups, the main substitutive analgesic was tramadol combined with acetaminophen, while only 24% of prescribers considered acetaminophen alone as a substitute.

Comparative pain reduction of oral non-steroidal anti-inflammatory drugs and opioids for knee osteoarthritis: systematic analytic review

OBJECTIVE

Summarize the comparative effectiveness of oral non-steroidal anti-inflammatory drugs (NSAIDs) and opioids in reducing knee osteoarthritis (OA) pain.

METHODS

Two reviewers independently screened reports of randomized controlled trials (RCTs), published in English between 1982 and 2015, evaluating oral NSAIDs or opioids for knee OA. Included studies were at least 8 weeks duration, conducted in Western Europe, the Americas, New Zealand, or Australia, and reported baseline and follow-up pain using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) Pain subscale (0-100, 100-worst). Effectiveness was evaluated as reduction in pain, accounting for study dropout and heterogeneity.

RESULTS

Twenty-seven treatment arms (nine celecoxib, four non-selective NSAIDs [diclofenac, naproxen, piroxicam], eleven less potent opioids [tramadol], and three potent opioids [hydromorphone, oxycodone]) from 17 studies were included. NSAID and opioid studies reported similar baseline demographics and efficacy withdrawal rates; NSAID studies reported lower baseline pain and toxicity withdrawal rates. Accounting for efficacy-related withdrawals, all drug classes were associated with similar pain reductions (NSAIDs: -18; less potent opioids: -18; potent opioids: -19). Meta-regression did not reveal differential effectiveness by drug class but found that study cohorts with a higher proportion of male subjects and worse mean baseline pain had greater pain reduction. Similarly, results of the network meta-analysis did not find a significant difference in WOMAC Pain reduction for the three analgesic classes.

CONCLUSION

NSAIDs and opioids offer similar pain relief in OA patients. These data could help clinicians and patients discuss likely benefits of alternative analgesics.

Prescription opioid epidemic and infant outcomes

BACKGROUND AND OBJECTIVES

Although opioid pain relievers are commonly prescribed in pregnancy, their association with neonatal outcomes is poorly described. Our objectives were to identify neonatal complications associated with antenatal opioid pain reliever exposure and to establish predictors of neonatal abstinence syndrome (NAS).

METHODS

We used prescription and administrative data linked to vital statistics for mothers and infants enrolled in the Tennessee Medicaid program between 2009 and 2011. A random sample of NAS cases was validated by medical record review. The association of antenatal exposures with NAS was evaluated by using multivariable logistic regression, controlling for maternal and infant characteristics.

RESULTS

Of 112,029 pregnant women, 31,354 (28%) filled ≥ 1 opioid prescription. Women prescribed opioid pain relievers were more likely than those not prescribed opioids (P < .001) to have depression (5.3% vs 2.7%), anxiety disorder (4.3% vs 1.6%) and to smoke tobacco (41.8% vs 25.8%). Infants with NAS and opioid-exposed infants were more likely than unexposed infants to be born at a low birth weight (21.2% vs 11.8% vs 9.9%; P < .001). In a multivariable model, higher cumulative opioid exposure for short-acting preparations (P < .001), opioid type (P < .001), number of daily cigarettes smoked (P < .001), and selective serotonin reuptake inhibitor use (odds ratio: 2.08 [95% confidence interval: 1.67-2.60]) were associated with greater risk of developing NAS.

CONCLUSIONS

Prescription opioid use in pregnancy is common and strongly associated with neonatal complications. Antenatal cumulative prescription opioid exposure, opioid type, tobacco use, and selective serotonin reuptake inhibitor use increase the risk of NAS.

Out-of-hospital mortality among patients receiving methadone for noncancer pain

IMPORTANCE

Growing methadone use in pain management has raised concerns regarding its safety relative to other long-acting opioids. Methadone hydrochloride may increase the risk for lethal respiratory depression related to accidental overdose and life-threatening ventricular arrhythmias.

OBJECTIVE

To compare the risk of out-of-hospital death in patients receiving methadone for noncancer pain with that in comparable patients receiving sustained-release (SR) morphine sulfate.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study was conducted using Tennessee Medicaid records from 1997 through 2009. The cohort included patients receiving morphine SR or methadone who were aged 30 to 74 years, did not have cancer or another life-threatening illness, and were not in a hospital or nursing home. At cohort entry, 32 742 and 6014 patients had filled a prescription for morphine SR or methadone, respectively. The patients' median age was 48 years, 57.9% were female, and comparable proportions had received cardiovascular, psychotropic, and other musculoskeletal medications. Nearly 90% of the patients received the opioid for back pain or other musculoskeletal pain. The median doses prescribed for morphine SR and methadone were 90 mg/d and 40 mg/d, respectively.

MAIN OUTCOMES AND MEASURES

The primary study end point was out-of-hospital mortality, given that opioid-related deaths typically occur outside the hospital.

RESULTS

There were 477 deaths during 28 699 person-years of follow-up (ie, 166 deaths per 10 000 person-years). After control for study covariates, patients receiving methadone had a 46% increased risk of death during the follow-up period, with an adjusted hazard ratio (HR) of 1.46 (95% CI, 1.17-1.83; P < .001), resulting in 72 (95% CI, 27-130) excess deaths per 10 000 person-years of follow-up. Methadone doses of 20 mg/d or less, the lowest dose quartile, were associated with an increased risk of death (HR, 1.59; 95% CI, 1.01-2.51, P = .046) relative to a comparable dose of morphine SR (<60 mg/d).

CONCLUSIONS AND RELEVANCE

The increased risk of death observed for patients receiving methadone in this retrospective cohort study, even for low doses, supports recommendations that it should not be a drug of first choice for noncancer pain.

Performance of time-dependent propensity scores: a pharmacoepidemiology case study

PURPOSE

Pharmacoepidemiologic studies of acute effects of episodic exposures often must control for many time-dependent confounders. Marginal structural models permit this and provide unbiased estimates when confounders are on the causal pathway. However, if causal pathway confounding is minimal, analyses with time-dependent propensity scores, calculated for time periods defined by individual drug prescriptions, may have better efficiency. We justify time-dependent propensity scores and compare the performance of these methods in a case study from a previous investigation of the risk of medication toxicity death in current users of propoxyphene and hydrocodone, with both substantial time-dependent confounding and a large number of covariates.

METHODS

The cohort included Tennessee Medicaid enrollees who filled a qualifying study opioid prescription between 1992 and 2007. We identified 22 time-dependent covariates that accounted for most of the confounding in the original study. We compared analyses with all covariates in the regression model with those based on time-dependent propensity scores and those from marginal structural models.

RESULTS

We identified 489,008 persons with 1,771,295 propoxyphene and 4,088,754 hydrocodone prescriptions. The unadjusted hazard ratio (propoxyphene : hydrocodone) was 0.70 (95%CI, 0.46-1.07). Estimates from inclusion of all covariates in the model, time-dependent propensity score analysis with inverse probability of treatment weighting, and marginal structural models were 1.63 (1.04-2.57), 1.65 (1.01-2.72), and 1.64 (0.83-3.27), respectively. Findings varied little with use of alternative propensity score methods, time origin, or techniques for marginal structural model estimation.

CONCLUSIONS

Time-dependent propensity scores may be useful for pharmacoepidemiologic studies with time-varying exposures when causal pathway confounding is limited.