Prescriptions of analgesics during complete disease trajectories in patients who are diagnosed with and die from cancer within the five-year period 2005-2009.

BACKGROUND: Even though validation studies of the WHO analgesic ladder have indicated that the simple approach of the analgesic ladder can provide adequate pain control in most patients, prevalence studies have documented a high prevalence of pain in cancer patients. Little is known about how analgesics are actually prescribed for cancer pain. The aim of the study was to study prescriptions of analgesics during the entire disease trajectory in patients dying from cancer within five years of diagnosis. METHODS: Complete national data from the Norwegian Cancer Registry, the Norwegian Prescription Database, the Cause of Death Registry and Statistics Norway were used to study prescriptions of analgesics in a complete study population of all patients dying from cancer within five years of diagnosis in Norway from 2005 to 2009. RESULTS: Of a total of 10,977 subjects who received prescriptions for analgesics between diagnosis and death, 56% started analgesic treatment at step I of the analgesic ladder, 29% started at step II and 14% started at step III. Of the patients starting at step I, 28% continued to step II, 37% bypassed step II and moved directly to step III whereas the remaining 35% remained at step I. Approximately 60% received one or more dispensed prescription of a step III analgesic during the disease trajectory, whereas nearly 20% remained at step I and 20% at step II respectively. CONCLUSION: The study indicates that clinicians seem to individually tailor analgesic treatment instead of applying the stepwise approach in the WHO analgesic ladder. SIGNIFICANCE: Complete national data covering the complete disease trajectory in cancer patients dying within five years of diagnosis. The majority of patients do not receive treatment in concordance with the stepwise approach suggested by the WHO analgesic ladder.

The duration and course of opioid therapy in patients with chronic non-malignant pain.

BACKGROUND: Prescription databases provide the opportunity for investigating opioid treatment and co-medication within large populations. So far, few studies have investigated the duration of opioid therapy, and large differences in discontinuation rates have been reported. METHODS: Data from the Norwegian Prescription Database were used to follow the study population of all adult persistent opioid users with non-malignant pain in Norway in 2005 (n = 44,867) for 6 years. Persistent opioid use was defined as being dispensed ≥ 180 defined daily doses (DDD) or 4500 mg oral morphine equivalents (OMEQ) during a 365-day period. The study population was stratified according to previous opioid use into new persistent opioid users, without previous persistent opioid use, and previous low-dose or previous high-dose persistent opioid users, having earlier persistent opioid use and received less or more than 120 mg OMEQ/day in 2005, respectively. RESULTS: Twenty-seven percent of new, 59% of previous low-dose, and 55% of previous high-dose users met the criteria of persistent use of opioids each year. Exactly, 22%, 11%, and 3% increased their cumulative yearly opioid dose by 200% or more during the study period. With 80% still being regular users of either drugs, 6 years later, long-term persistent opioid users were more likely to continue concomitant use of benzodiazepines or z-hypnotics than other users, CONCLUSION: The findings confirm high discontinuation rates in patients receiving opioids for chronic non-malignant pain. However, a clinically significant number of patients increase their doses over 6 years and many patients combine long-term opioid treatment with benzodiazepines and z-hypnotics.

Long- or short-acting opioids for chronic non-malignant pain? A qualitative systematic review.

In selected patients with chronic non-malignant pain, chronic opioid therapy is indicated. Published guidelines recommend long-acting over short-acting opioids in these patients. The aim of this systematic review was to investigate whether long-acting opioids in chronic non-malignant pain are superior to short-acting opioids in pain relief, physical function, sleep quality, quality of life or adverse events. This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. PubMed, Embase and Cochrane Central Register of Controlled Trials were searched for relevant trials up to July 2012. Reference lists of included trials and relevant reviews were in addition searched by hand. Of the 1168 identified publications, 6 randomised trials evaluating efficacy and safety filled the criteria for inclusion. None of them found a significantly better pain relief, significantly less consumption of rescue analgesia, improved quality of sleep or improved physical function from long-acting opioids. None of the trials investigated quality of life. None of the trials investigated adverse events properly nor addiction, tolerance or hyperalgesia. Three trials in healthy volunteers with a recreational drug use, found no difference in abuse potential between long- and short-acting opioids. While long term, comparative data are lacking, there is fair evidence from short-term trials that long-acting opioids provide equal pain relief compared with short-acting opioids. Contrary to several guidelines, there is no evidence supporting long-acting opioids superiority to short-acting ones in improving functional outcomes, reducing side effects or addiction.

Co-morbidity in persistent opioid users with chronic non-malignant pain in Norway.

BACKGROUND: In patients with chronic non-malignant pain (CNMP), co-morbid physical or mental health disorders are common and may have a negative impact on health-related quality of life and treatment outcomes. The purpose of this study was to examine the occurrence of chronic psychiatric and somatic diseases in persistent opioid users with CNMP compared with the general population in Norway. METHODS: In this cross-sectional study, prescription patterns of dispensed opioids were used to identify a study population of persistent opioid users with CNMP from the general population. Reimbursed prescriptions marked with diagnostic codes were used to identify the occurrence of 21 somatic and 3 psychiatric diseases for a 1-year period in the Norwegian Prescription Database. Occurrence of disease in persistent opioid users was compared to an age- and gender-specific population of all Norwegian residents aged 18-79 years in 2009. Standardized morbidity ratios (SMRs) for each disease were calculated. RESULTS: Eighty-five percent of the persistent opioid user population had at least one co-morbid disease compared with 45% of the general population. Forty-two percent had three or more co-morbidities. SMRs in both men and women were generally increased except for dementia, glaucoma and renal disease, indicating a higher occurrence of disease in persistent opioid users. CONCLUSIONS: A higher occurrence of both somatic and psychiatric co-morbidities in disease stages warranting pharmacological treatment was found in persistent opioid users with CNMP compared with the general population of Norway.

Concomitant medication among persistent opioid users with chronic non-malignant pain.

BACKGROUND: Recent guidelines for opioid treatment of chronic non-malignant pain discourage co-medication with benzodiazepines and benzodiazepine-related hypnotics, whereas co-medication with non-opioid analgesics and co-analgesics may offer a beneficial opioid sparing effect, and is recommended. The aim of this study was to describe 1-year periodic prevalence of co-medication with benzodiazepines, benzodiazepine-related hypnotics, non-opioid analgesics, co-analgesics and antidepressants in persistent opioid users with chronic non-malignant pain. METHODS: The study is based on data from the Norwegian Prescription Database, covering all drugs dispensed to outpatients in 2008. Concomitant medication levels were compared between users in two definitions of persistent opioid use, all Norwegian adults dispensed opioids in 2008 and the Norwegian background population. RESULTS: Of the Norwegian adult population studied, 1.2% met the criteria of persistent opioid use based on prescription pattern and prescription level. Sixty percent of persistent opioid users were dispensed a benzodiazepine or benzodiazepine-related hypnotic in amounts indicating regular use, with 15% dispensed a high amount of both classes. Sixty-two percent of persistent opioid users were dispensed one or more non-opioid analgesics, 47% an antidepressant and 33% were dispensed an antiepileptic drug. CONCLUSION: Approximately 60% of persistent opioid users also receive benzodiazepines or benzodiazepine-related hypnotics in amounts indicating regular use. This is in conflict with recent guidelines for the treatment of chronic non-malignant pain and may indicate that these users are at an increased risk of developing problematic opioid use.

Differential patterns of opioid use: defining persistent opioid use in a prescription database.

AIM: The aim of this study was to develop definitions to identify persons with clinically different patterns of persistent opioid use based on data from prescription databases. METHODS: The study is based on data from the Norwegian Prescription Database using all dispensed opioid prescriptions during 2005-2008. Three definitions of persistent opioid use were developed using the following patient criteria: different levels of dispensed opioid amounts, number of prescriptions and the number of quarters out of the year in which prescriptions were dispensed. The three definitions each have some typical patient characteristics attached to them. The strict definition describes a typical patient using opioids to achieve a continuous serum concentration in the therapeutic range, the intermediate definition represents a typical patient using opioids daily but not around the clock and the wide definition describes a typical patient who uses opioids most of the days. To study whether the definitions accurately represent long-term use, the patient population was followed for 3 years, and the retention rate within each definition was measured. RESULTS: The point prevalence of persistent opioid use in Norway (4,681,134 inhabitants) as defined by the strict, intermediate and wide definitions was 0.16% (n = 7663), 0.50% (n = 23,498) and 1.08% (n = 50,791), respectively, as of 31 December 2007. At the end of the 3-year study period, the retention within any of the definitions was 83%, 84% and 68% for patients who met the criteria of the strict, intermediate and wide definitions, respectively. CONCLUSION: In the patient populations identified by the three definitions, a high rate of retention was observed, indicating that the proposed definitions can identify patients with long-term persistent use of opioids.

Prescription pattern of codeine for non-malignant pain: a pharmacoepidemiological study from the Norwegian Prescription Database.

BACKGROUND: Opioid prescription for pain relief is increasing. Codeine is the dominating opioid in several European countries, with Norway being among the highest codeine users. AIM: To determine whether codeine is primarily used for acute pain or whether there is a prescription pattern indicating problematic opioid use. METHODS: All pharmacies in Norway are obliged to submit data electronically to the Norwegian Prescription Database at the Norwegian Institute of Public Health on all dispensed prescriptions. Because all prescriptions are identified with a unique person identifier, it is possible to identify all prescriptions to one subject. All subjects who had prescription(s) of codeine dispensed to them in 2004, 2005 or 2006 are included in the study. RESULTS: 385 190 Norwegian persons had at least one prescription of codeine dispensed to them due to non-cancer pain in 2005, corresponding to a 1-year periodic prevalence of 8.3%. 223 778 (58%) received only one prescription in 2005, 121 025 (31%) received more than one prescription but <120 defined daily doses (DDDs), 30 939 (8%) received between 120 and 365 DDDs, 7661 (2%) between 365 and 730 DDDs, while only 1787 (0.5%) exceeded the maximum recommended dose of 730 DDDs. In the latter group, co-medication with benzodiazepines (65%) and carisoprodol (45%) was prevalent. CONCLUSION: About one in 10 adult persons in Norway were dispensed codeine in 2005. A majority (58%) received codeine only once, most likely for acute pain, whereas a small minority (0.5%) had a prescription pattern indicating problematic opioid use.

Clinical pharmacology of methadone for pain.

BACKGROUND: This topical review addresses methadone's pharmacology, its application in malignant and non-malignant pain conditions, practical issues related to methadone for the treatment of pain and its influence on QTc time. METHODS: Relevant papers were identified in PubMed and EMBASE. RESULTS: Methadone is advocated by experts as a second line opioid when first line opioids fail to provide a satisfactory balance between pain control and side effects (opioid switching). Although randomized-controlled studies are lacking, current evidence suggests that switching to methadone in this situation reduces pain intensity. However, interindividual variability in its pharmacokinetics make its application challenging and metabolism by CYP 3A4 and 2B6 implies a substantial risk of drug-drug interactions. Several ways of switching to methadone have been presented, with a gradual switch during 3 days or 'stop and go' as the dominating strategies. Episodes of torsade de pointes arrhythmia during methadone treatment have been reported in patients with other risk factors for arrhythmia, while small prospective studies have reported a small, lasting and stable increase in QTc time. The extensive use of methadone for opioid replacement in addicts has added additional patient barriers to its use for pain control. CONCLUSION: In spite of challenges related to the variable pharmacokinetics and concerns regarding increase in QTc time, current evidence indicates that opioid switching to methadone improves pain control in a substantial proportion of patients who are candidates for opioid switching. Measures must be instituted to secure that patients receiving methadone for pain are not considered opioid addicts.

Chronic non-malignant pain patients report as poor health-related quality of life as palliative cancer patients.

BACKGROUND: Patients with chronic non-malignant pain (CNMP) conditions are known to report reduced health-related quality of life (HRQoL). The objective of this exploratory study was to compare HRQoL between patients admitted to a multidisciplinary pain centre, palliative cancer (PC) patients and national norms. METHODS: HRQoL data from 288 patients with CNMP admitted to the multidisciplinary pain centre at Trondheim University Hospital were compared with 434 patients with advanced cancer included in a trial of comprehensive palliative care in the hospital palliative medicine unit and national norms. HRQoL was assessed using the EORTC QLQ-C30. Age- and gender-adjusted norm data were calculated and compared between the two groups. RESULTS: Scores from both groups deviated from adjusted norm data on all scales, with poorer functioning and more symptoms. Compared with PC patients, CNMP patients reported a larger deviation (worse scores) on global quality of life, cognitive functioning, pain, sleep disturbances and financial difficulties. Deviations from norm data were similar for physical, social and emotional functioning, diarrhoea, dyspnoea and fatigue. PC patients reported worse scores on role functioning, nausea/vomiting, loss of appetite and constipation. CONCLUSION: CNMP patients admitted to multidisciplinary pain centres report significantly reduced HRQoL, in addition to severe pain. They consider their HRQoL to be as poor as HRQoL reported from dying cancer patients and substantially poorer than national norms. Factors other than the biological severity of the disease seem to be of major importance for self-reported HRQoL.