A Compilation of Serum Concentrations of 12 Antipsychotic Drugs in a Therapeutic Drug Monitoring Setting.

BACKGROUND: No comprehensive collection of routine therapeutic drug monitoring data for antipsychotic drugs has been published. METHODS: In this compilation, data on 12 antipsychotics are presented. The drugs included are amisulpride (n = 506), aripiprazole (n = 1610), clozapine (n = 1189), flupentixol (n = 215), haloperidol (n = 390), olanzapine (n = 10,268), perphenazine (n = 1065), quetiapine (n = 5853), risperidone (n = 3255), sertindole (n = 111), ziprasidone (n = 1235), and zuclopenthixol (n = 691). Because only one sample per patient is included, the number of patients equals the number of samples. For each drug, median serum concentrations as well as that of the 10th and 90th percentiles are given for a range of daily doses. Comparisons are made between males and females, between patients younger than 65 years and 65 years and older, and between those treated with a low and a high dose of each drug. The concentration-to-dose (C/D) ratio is the primary variable used in these comparisons. Coefficients of variation (CVs) for the serum concentrations of each drug within and between subjects are presented. RESULTS: In general, the C/D ratios were higher in females than in males, higher in those 65 years and older than in younger subjects, and lower in those treated with higher doses than in those treated with lower doses. CVs between individuals were larger than within subjects, and the CVs were highest for the drugs with short elimination half-lives. CONCLUSIONS: For each antipsychotic drug, the results presented can serve as a reference tool for pharmacokinetic interpretation of the individual patient's serum drug level. The compiled serum concentrations and the C/D ratios can support the physician's decision when individualizing dosing and determining treatment strategies for a specific patient.

Comparing Methods for Estimating Direct Costs of Adverse Drug Events.

OBJECTIVES: To estimate how direct health care costs resulting from adverse drug events (ADEs) and cost distribution are affected by methodological decisions regarding identification of ADEs, assigning relevant resource use to ADEs, and estimating costs for the assigned resources. METHODS: ADEs were identified from medical records and diagnostic codes for a random sample of 4970 Swedish adults during a 3-month study period in 2008 and were assessed for causality. Results were compared for five cost evaluation methods, including different methods for identifying ADEs, assigning resource use to ADEs, and for estimating costs for the assigned resources (resource use method, proportion of registered cost method, unit cost method, diagnostic code method, and main diagnosis method). Different levels of causality for ADEs and ADEs' contribution to health care resource use were considered. RESULTS: Using the five methods, the maximum estimated overall direct health care costs resulting from ADEs ranged from Sk10,000 (Sk = Swedish krona; ~€1,500 in 2016 values) using the diagnostic code method to more than Sk3,000,000 (~€414,000) using the unit cost method in our study population. The most conservative definitions for ADEs' contribution to health care resource use and the causality of ADEs resulted in average costs per patient ranging from Sk0 using the diagnostic code method to Sk4066 (~€500) using the unit cost method. CONCLUSIONS: The estimated costs resulting from ADEs varied considerably depending on the methodological choices. The results indicate that costs for ADEs need to be identified through medical record review and by using detailed unit cost data.

Adherence to antidepressants among women and men described with trajectory models: a Swedish longitudinal study.

PURPOSE: The purpose of this study are to analyse adherence to antidepressant treatment over 2 years in Sweden among women and men who initiated treatment with citalopram and to identify groups at risk of non-adherence using trajectory models. METHODS: The study population, including individuals 18-85 years who initiated citalopram use between 1 July 2006 and 30 June 2007, was identified in the Swedish Prescribed Drug Register and followed for 2 years. Adherence was estimated with continuous measure of medication acquisition (CMA) and group-based trajectory modelling, a method which describes adherence patterns over time by estimating trajectories of adherence and the individual's probability of belonging to a specific trajectory. RESULTS: The study population included 54,248 individuals, 64 % women. Mean CMA was 52 % among women and 50 % among men (p < 0.001). Five different adherence patterns (Trajectories) were identified. Similar proportion of women and men belonged to each Trajectory. Around 29 % of the women and 27 % of the men belonged to the Trajectory which showed full adherence throughout the 2-year study period. The other four Trajectories showed adherence that declined to different degrees and at different stages in time. Having low socioeconomic status was more common among individuals in Trajectories showing declining adherence than in the adherent Trajectory. CONCLUSIONS: Using trajectory modelling, five Trajectories describing different patterns of adherence to citalopram treatment over time were identified. A large proportion discontinued treatment early and having low socioeconomic status increased the risk of being non-adherent.

Potentially inappropriate prescribing and adverse drug reactions in the elderly: a population-based study.

PURPOSE: Potentially inappropriate prescriptions (PIPs) criteria are widely used for evaluating the quality of prescribing in elderly. However, there is limited evidence on their association with adverse drug reactions (ADRs) across healthcare settings. The study aimed to determine the prevalence of PIPs, defined by the Screening Tool of Older Persons' potentially inappropriate Prescriptions (STOPP) criteria, in the Swedish elderly general population and to investigate the association between PIPs and occurrence of ADRs. METHOD: Persons ≥65 years old were identified from a random sample of 5025 adults drawn from the Swedish Total Population Register. A retrospective cohort study was conducted among 813 elderly with healthcare encounters in primary and specialised healthcare settings during a 3-month period in 2008. PIPs were identified from the Swedish Prescribed Drug Register, medical records and health administrative data. ADRs were independently identified by expert reviewers in a stepwise manner using the Howard criteria. Multivariable logistic regression examined the association between PIPs and ADRs. RESULTS: Overall, 374 (46.0 %) persons had ≥1 PIPs and 159 (19.5 %) experienced ≥1 ADRs during the study period. In total, 29.8 % of all ADRs was considered caused by PIPs. Persons prescribed with PIPs had more than twofold increased odds of experiencing ADRs (OR 2.47; 95 % CI 1.65-3.69). PIPs were considered the cause of 60 % of ADRs affecting the vascular system, 50 % of ADRs affecting the nervous system and 62.5 % of ADRs resulting in falls. CONCLUSION: PIPs are common among the Swedish elderly and are associated with increased odds of experiencing ADRs. Thus, interventions to decrease PIPs may contribute to preventing ADRs, in particular ADRs associated with nervous and vascular disorders and falls.

The impact of a changed legislation on reporting of adverse drug reactions in Sweden, with focus on nurses' reporting.

PURPOSE: In March 2007, a legislative amendment was issued in Sweden compelling nurses to report all suspected adverse drug reactions (ADRs) to the national pharmacovigilance system. The aims of this study were to describe the status of ADR reporting, before and after the implementation of the legislative changes, and to describe the general characteristics of suspected ADRs reported by nurses. METHODS: The Swedish pharmacovigilance system during the study period constituted six regional centres responsible for the handling of all spontaneous ADR reports within their region. In this study, we identified all individual ADR reports from 2005 and 2010, analysed in depth the ADR reports from two regional centres and collated information about the reporter and the nature of the reported ADR. RESULTS: From the two regional centres, a total of 898 and 1074 reports were submitted in 2005 and 2010 respectively. Nurses submitted 31% (275 reports) of the reports in 2005 and 24% (260 reports) in 2010. Nurses' reporting of serious ADRs was 3% (seven reports) in 2005 and 7% (17 reports) in 2010 with reporting of unlabelled ADRs at 4% (11 reports) in 2005 and 17% (45 reports) in 2010. Most of the serious and/or unlabelled reactions were related to vaccine administration (14 reports in 2005 and 36 reports in 2010). CONCLUSIONS: The overall ADR reporting by nurses did not appear to increase after the change in reporting legislation. The proportion of serious and/or unlabelled ADRs reported by nurses did however appear to increase during the same period. Taken together, our data suggests that further pro-active measures should be considered in order to involve nurses in the reporting of suspected ADRs.

Prevalence, nature and potential preventability of adverse drug events - a population-based medical record study of 4970 adults.

AIMS: To estimate the 3 month prevalence of adverse drug events (ADEs), categories of ADEs and preventable ADEs, and the preventability of ADEs among adults in Sweden. Further, to identify drug classes and organ systems associated with ADEs and estimate their seriousness. METHODS: A random sample of 5025 adults in a Swedish county council in 2008 was drawn from the Total Population Register. All their medical records in 29 inpatient care departments in three hospitals, 110 specialized outpatient clinics and 51 primary care units were reviewed retrospectively in a stepwise manner, and complemented with register data on dispensed drugs. ADEs, including adverse drug reactions (ADRs), sub-therapeutic effects of drug therapy (STEs), drug dependence and abuse, drug intoxications from overdose, and morbidities due to drug-related untreated indication, were detected during a 3 month study period, and assessed for preventability. RESULTS: Among 4970 included individuals, the prevalence of ADEs was 12.0% (95% confidence interval (CI) 11.1, 12.9%), and preventable ADEs 5.6% (95% CI 5.0, 6.2%). ADRs (6.9%; 95% CI 6.2, 7.6%) and STEs (6.4%; 95% CI 5.8, 7.1%) were more prevalent than the other ADEs. Of the ADEs, 38.8% (95% CI 35.8-41.9%) was preventable, varying by ADE category and seriousness. ADEs were frequently associated with nervous system and cardiovascular drugs, but the associated drugs and affected organs varied by ADE category. CONCLUSIONS: The considerable burden of ADEs and preventable ADEs from commonly used drugs across care settings warrants large-scale efforts to redesign safer, higher quality healthcare systems. The heterogeneous nature of the ADE categories should be considered in research and clinical practice for preventing, detecting and mitigating ADEs.

Is the level of patient co-payment for medicines associated with refill adherence in Sweden?

BACKGROUND: In the Swedish reimbursement scheme, the co-payment is based on the price of the product and decreases in a stepwise manner as the total accumulated co-payment increases. The aim of this study was to analyse how refill adherence in Sweden varies according to patient's co-payment level for medicines, with antiepileptic drug (AED) use as an example. METHODS: Prevalent AED users aged 18-85 years who purchased an AED between 1 January and 30 June 2007 were identified in the Swedish Prescribed Drug Register and followed for a maximum of 2 years. Patient time was categorized based on patient's accumulated co-payment for all drugs per reimbursement period. The continuous measure of medication acquisition (CMA) was used to estimate refill adherence in relation to the patients' co-payment level. Associations between patients' co-payment for all medicines and refill adherence were assessed with multilevel mixed-effects linear regression, accounting for clustering within patients. RESULTS: The study population included 2210 patients (mean age: 56 years; 54% men). CMA for AED was 91% for patients where the co-payment corresponded to 100% of the price. Compared with these patients, refill adherence for AED was 2-4% higher (P < 0.001) for patients with reduced co-payment (co-payment of ≤50% of the price). Higher age, higher income and fenytoin use were also associated with a higher refill adherence for AED. CONCLUSIONS: Using AED as an example, a higher level of reimbursement was associated with a higher refill adherence compared with full co-payment in Sweden.

Fatal Intoxications with Zopiclone-A Cause for Concern?

INTRODUCTION: Zopiclone, a controlled substance prescribed for insomnia, has become a common toxicological finding in forensic autopsy cases. This study investigated the role and extent of zopiclone use in fatal intoxications in Sweden. METHODS: All forensic autopsy cases positive for zopiclone in femoral blood during 2012-2020 were selected. Among these cases, fatalities caused by intoxication according to the cause of death certificates issued by the forensic pathologist were identified. Intoxications where zopiclone contributed to the cause of death were included in the study. The Swedish Prescribed Drug Register was utilized to examine whether the included cases were prescribed zopiclone or not. RESULTS: In total 7320 fatal intoxications underwent a forensic autopsy during the study period, 573 of them were caused by zopiclone. Among the zopiclone fatalities, 87% (n = 494) had a prescription for zopiclone, and 8% (n = 43) were monointoxications. Most fatalities, 62% (n = 354) were suicides, and zopiclone was involved in about 17% (n = 354) of all intoxication suicides in Sweden. Women were significantly (p < 0.01) overrepresented in suicides with zopiclone, comprising 56% (n = 291) of fatalities. The median age was 55 years among zopiclone intoxications compared with 44 years amongst all fatal intoxications. CONCLUSION: This study demonstrates that the toxicity of zopiclone can be lethal both in combination with other substances and on its own. Most individuals dying in fatal zopiclone intoxications were prescribed zopiclone, which potentially indicates that a more restrictive prescribing rate could prevent future intoxication deaths, especially when caring for patients with an increased suicide risk.

A prospective analysis of the preventability of adverse drug reactions reported in Sweden.

PURPOSE: Adverse drug reactions (ADRs) are a major patient safety issue, and a substantial proportion of ADRs are, in fact, preventable. The aim of this study was to describe the proportion and pattern of preventable ADRs in spontaneously reported suspected ADRs and to study the feasibility of using data from an ADR reporting system for this purpose. METHODS: All reports of ADRs, except those in which a vaccine was the suspected drug, submitted to the regional pharmacovigilance center of southeastern Sweden between 2008 and 2009 were analyzed. Causality between the suspected ADR and the medication was assessed using the World Health Organization (WHO) criteria, and preventability was assessed using Hallas criteria. RESULTS: During the study period, 1,290 ADRs were received and 1,255 were classified as having at least a possible causality between a reaction and a drug. Of these, 172 (14%) ADRs were considered preventable, 35 (20%) were classified as definitely preventable, and 137 (80%) as possibly preventable. Of all preventable ADRs, 96 (56%) were related to prescribing, 35 (20%) to administration, and 41 (24%) to clinical and laboratory monitoring of treatment. Warfarin, oxycodone, and ioversol were the most common drugs with preventable ADRs. CONCLUSIONS: This study found that a substantial part of reported ADRs are preventable. Most of these are related to drug prescription, suggesting that interventions aiming to reduce preventable ADRs should focus on this process. Moreover, systems for ADR reporting may be useful in the mission of reducing the unsafe use of drugs.

Use of Lisdexamfetamine or Amphetamine? Interpretation of Chiral Amphetamine Analyses.

Amphetamine is frequently detected in forensic toxicological cases. Differentiating between the two isomers of amphetamine (d-amphetamine and l-amphetamine) and determining their relative proportion are fundamental to correctly interpret the results of toxicological analyses. The aim of this study was to examine the profile of amphetamine as well as storage stability of the isomers in authentic samples from patients chronically treated with lisdexamfetamine (LDX), the most prescribed medical amphetamine product in Sweden. Blood and urine samples were collected from 18 patients. The samples were analyzed with an achiral (racemate) method for quantification of amphetamine and with a chiral method to determine the proportion of each isomer of amphetamine. The median daily dose of LDX was 40 mg (range, 20-70 mg). The median amphetamine concentration was 0.06 µg/g (range, 0.02-0.15 µg/g) in blood and 6 µg/mL (range, 1-22 µg/mL) in urine. Only d-amphetamine was found in the blood and urine samples from the included patients. Furthermore, no formation of l-amphetamine occurred during the storage for 3 months at 4°C, 9 months at -20°C and three freeze-thaw cycles. The results from this study may be helpful in the interpretation of whether the source of identified amphetamine in biological samples is from LDX drug intake or not.

Oxycodone-Related Deaths: The Significance of Pharmacokinetic and Pharmacodynamic Drug Interactions.

BACKGROUND AND OBJECTIVES: Oxycodone is frequently prescribed as well as detected in postmortem cases. Concurrent use of pharmacodynamically or pharmacokinetically interacting drugs can cause adverse effects or even fatal intoxication. The aims of this study were to investigate differences in prescriptions for and toxicological findings of pharmacodynamically and pharmacokinetically interacting drugs in fatal oxycodone-related intoxications and other causes of death. We also aimed to investigate the differences in prevalence of oxycodone prescriptions, and the detected postmortem oxycodone concentrations between fatal oxycodone-related intoxications and other causes of death. METHODS: Forensic autopsy cases (2012-2018) where oxycodone was identified in femoral blood (n = 1236) were included. Medical history and prescription data were retrieved from national databases and linked to the forensic toxicology findings. RESULTS: Oxycodone-related deaths were found to have higher blood concentrations of oxycodone (median 0.30 µg/g vs. 0.05 µg/g) and were less likely to have a prescription for oxycodone (OR 0.62) compared to nonintoxication deaths. Pharmacodynamically interacting drugs were prescribed in 79% and found in blood in 81% of the cases. Pharmacokinetically interacting drugs were rarely prescribed (1%). Oxycodone-related deaths were more likely to have prescriptions for a pharmacodynamically interacting drug (OR 1.7) and more often have co-findings of one or multiple pharmacodynamically interacting drugs (OR 5.6). CONCLUSION: The results suggest that combined use of oxycodone and pharmacodynamically interacting drugs is associated with oxycodone-related death and that non-medical use of oxycodone is a potential risk factor for oxycodone-related intoxication.

A comparison of two methods for estimating refill adherence to statins in Sweden: the RARE project.

PURPOSE: To analyse and compare refill adherence to statins estimated with two different methods with a focus on sensitivity to definitions. METHODS: Individuals aged 18-85 years who filled a statin prescription for the first time in 1.5 years during 1 January-30 June 2007 were followed until emigration or death or until 2 years after their first statin purchase. The data were collected via linkage between the Swedish Prescribed Drug Register, the National Patient Register and the Total Population Register. Days' supply was estimated based on amount dispensed and prescribed dosage. Refill adherence was estimated with the continuous measure of medication acquisition (CMA) and the maximum gap method (cut-off 45 days). The impact of altering definitions, for example, regarding hospitalisations, length of observation period and management of overlapping supply, was analysed. RESULTS: The study included 36, 661 individuals (mean age 64 years, 47% women). The median proportion of days with statins was 95%, and 76% were classified as adherent with a cut-off at ≥ 80% with CMA. With the maximum gap method, 65% were adherent. Disregarding hospitalisations did not alter the results. Emigration or death at least one year after statin initiation was associated with a lower adherence with both methods, and a shorter observation period and adding overlapping supply to the subsequent prescription increased the adherence estimates. CONCLUSIONS: The choice of method and definitions, particularly regarding the management of overlapping supplies and the length of observation period, has a substantial impact on estimates of refill adherence to statins.

Characteristics of post-mortem beta-hydroxybutyrate-positivet cases - A retrospective study on age, sex and BMI in 1407 forensic autopsies.

BACKGROUND: Post-mortem biochemistry, including the analysis of beta-hydroxybutyrate (BHB), is increasingly employed in forensic medicine, especially in conditions such as diabetes and chronic alcoholism. However, not much is known about the associations between age, body mass index (BMI), and sex and BHB concentrations in ketoacidotic conditions. AIM: To retrospectively study the association between age, BMI and sex in several conditions, such as diabetic ketoacidosis (DKA), alcoholic ketoacidosis (AKA), and elevated post-mortem BHB concentrations. METHODS: 1407 forensic autopsy cases analysed for BHB were grouped by diagnosis: DKA, AKA, HHS [hyperosmolar hyperglycaemic state], acidosis NOS [not otherwise specified], or hypothermia. Age, sex, BMI and the concentrations of blood alcohol, vitreous glucose and blood BHB were recorded. RESULTS: Cases of AKA and DKA were most numerous (184 and 156, respectively). In DKA and in its male subgroup, cases with severe ketosis (BHB>1000 µg/g) were younger and had a lower BMI than those with moderate ketosis (BHB 250-1000 µg/g) and controls (P<0.001). In DKA and in its female subgroup, cases with moderate ketosis cases were older (P = 0.0218 and P = 0.0083) than controls. In AKA and in its male subgroup, cases with severe ketosis had a lower BMI than those with moderate ketosis (P = 0.0391 and P = 0.0469) and controls (P<0.001). Cases with moderate ketosis had a lower BMI than controls (P<0.001). CONCLUSIONS: BHB concentration is associated with BMI in DKA and AKA, and with both BMI and age in DKA. Constitutional factors should, therefore, be considered in potential AKA and DKA cases.

The Importance of BHB Testing on the Post-Mortem Diagnosis of Ketoacidosis.

Although beta-hydroxybutyrate (BHB) analysis has proved its importance in forensic pathology, its effects on cause-of-death diagnostics are unaddressed. Therefore, this study aims at evaluating the effects of BHB analysis on the number of deaths by DKA (diabetes ketoacidosis), AKA (alcoholic ketoacidosis), HHS (hyperosmolar hyperglycaemic state), hypothermia, diabetes, alcoholism, and acidosis NOS (not otherwise specified). All 2900 deaths from 2013 through 2019 in which BHB was analysed at the National Board of Forensic Medicine, and 1069 DKA, AKA, HHS, hypothermia, diabetes, alcoholism, and acidosis cases without BHB analysis were included. The prevalence of BHB-positive cases for each cause of death, and trends and proportions of different BHB concentrations, were investigated. The number of BHB analyses/year increased from 13 to 1417. AKA increased from three to 66 and acidosis from one to 20. The deaths from alcoholism, DKA, and hypothermia remained stable. It is unclear why death from alcoholism remained stable while AKA increased. The increase in unspecific acidosis deaths raises the question why a more specific diagnosis had not been used. In conclusion, BHB analysis is instrumental in detecting AKA and acidosis. The scientific basis for the diagnosis of DKA and hypothermia improved, but the number of cases did not change.

Preventable drug related mortality in a Swedish population.

PURPOSE: Several studies indicate that the medical burden of fatal adverse drug reactions (FADRs) is significant, but the preventability of FADRs in the general population is largely unknown. The aim of this study was to determine the proportion of preventable FADRs and preventable fatal drug poisonings (FDPs) in a Swedish population. METHODS: Previously, a population-based sample of 1574 deceased subjects was scrutinised for FADRs and FDPs using relevant case records, including death certificates, medical charts and medico-legal files. Forty-nine cases (3%) of FADRs and nine cases (0.6%) of FDPs were identified in 57 subjects. In this study, the preventability of all these identified FADRs and FDPs was evaluated by clinical experts in a stepwise manner, applying a set of predefined and well established preventability criteria. Only cases for which consensus was achieved were included in the study. RESULTS: Of 49 FADRs, 14% (seven fatalities) was considered definitely or possibly preventable and four of these were due to the presence of a contraindication for the drug. All nine FDPs were considered possibly preventable. As one subject had a combination of an FADR and an FDP, a total of 15 persons (26%) were considered having a definitely or possibly preventable FADR or FDP, corresponding to 0.95% of all deceased subjects in Sweden. CONCLUSIONS: The results of this study indicate that approximately one fourth of FADRs and FDPs could be prevented. Therefore, an increased awareness of the possibility to reduce the risk of fatal events due to pharmaceutical drugs is warranted.

Current Evidence on Abuse and Misuse of Gabapentinoids.

This review summarizes current evidence on the abuse and misuse of the gabapentinoids pregabalin and gabapentin. Pharmacovigilance studies, register-based studies, surveys, clinical toxicology studies, and forensic toxicology studies were identified and scrutinized with the goal to define the problem, identify risk factors, and discuss possible methods to reduce the potential for abuse and misuse. Studies found that gabapentinoids are abused and misused and that individuals with a history of psychiatric disorders or substance use disorder seem to be at high risk. Moreover, some evidence supports the notion that patients with opioid use disorders may be at an increased risk of abusing gabapentinoids. Available evidence also suggests that abuse and misuse are more frequent in users of pregabalin compared with users of gabapentin. Health professionals and prescribers should be aware of the risk for misuse of pregabalin and gabapentin, which eventually could lead to abuse, substance dependence, and intoxications. Prescribing to patients belonging to risk populations such as those with psychiatric disorders or substance use disorder should be avoided if possible and, if prescribed, signs of misuse and abuse should be monitored.

Spontaneously reported adverse reactions in association with complementary and alternative medicine substances in Sweden.

PURPOSE: Although the safety information is limited, use of complementary and alternative medicine (CAM) products is not without risks. Spontaneous reporting systems may be used in the surveillance of these products. We describe the pattern of spontaneously reported CAM related adverse reactions submitted to the Swedish Medical Products Agency (MPA) and highlight areas of safety concern. METHODS: All adverse reactions spontaneously reported to MPA between 1987 and 2006, where at least one CAM substance was a suspected agent, were scrutinised. From each report information about the patient, adverse reaction/s, drug treatment/s, dosage, time relationship and outcome was retrieved. RESULTS: Among a total of 64 493 reports, 778 reports concerned 967 suspected adverse reactions related to 175 different CAM products. The main distribution of suspected adverse reactions was: urticaria (8.3%), exanthema (7.4%) and contact dermatitis (5.7%). The most reported CAM substances were purple coneflower (Echinacea purpurea) (8.1%), purple coneflower + siberian ginseng (Eleutherococcus senticosus) + malabar nut (Adhatoda vasica) (7.3%) and ginkgo leaf (Ginkgo biloba) (6.7%). In 221 reports, at least one reaction was categorised as serious, the most frequent being pulmonary embolism (1.7%), mixed liver reaction (2.8%), and anaphylactic reaction (2.0%). Eleven of the serious adverse reactions had a fatal outcome. CONCLUSIONS: CAM substances were associated with a variety of adverse reactions. Some of these have previously been unrecognised or poorly documented and suggest further investigations. By stimulating the reporting of adverse reactions of CAM products, the signal detection power of the spontaneous reporting system may increase further.

Tramadol dependence: a survey of spontaneously reported cases in Sweden.

BACKGROUND: Tramadol is a weak opioid analgesic, which is generally considered to be safe. However, conflicting data exist on the dependence potential of tramadol. OBJECTIVE: The aim of this study was to investigate occurrence of tramadol dependence and associated risk factors using spontaneously reported adverse drug reactions. METHODS: The Swedish database for spontaneously reported adverse drug reactions, Swedish Drug Information System (SweDIS), was searched for reports on tramadol dependence from 1 January 1995 until 31 December 2006. Selection was conducted based on the DSM-IV definition of dependence. Available information was scrutinised and registered and then presented descriptively. RESULTS: A total of 104 reports of tramadol dependence were identified, of which 60 (58%) concerned women. The median age (range) was 45 (15-84) years. Information on a history of substance abuse was present in 31 patients (30%) and 41 patients (39%) had a documented past or current use of a drug of abuse. Prescribed doses of tramadol ranged between 50-800 mg/day, and ingested doses between 50-4000 mg/day. Time of onset ranged from some weeks up to 4 years. In 72 (69%) cases the reaction was classified as serious, mainly due to hospitalisations for detoxification or discontinuation of tramadol. CONCLUSIONS: There is an occurrence of tramadol dependence in association with analgesic treatment within the recommended dose range. In susceptible patients a severe and serious dependence syndrome may develop. A history of abuse or use of a drug of abuse seems to be an important risk factor.

Fatal drug poisonings in a Swedish general population.

BACKGROUND: Pharmaceutical drug poisonings have previously been reported using single sources of information, either hospital data or forensic data, which might not reveal the true incidence. We therefore aimed to estimate the incidence of suspected fatal drug poisonings, defined as poisonings by pharmaceutical agents, by using all relevant case records from various sources in a Swedish population. METHODS: Every seventh randomly selected deceased in three counties in southeastern Sweden during a one-year period was identified in the Cause of Death Register. Relevant case records (death certificates, files from hospitals and/or primary care centres and medico-legal files) were reviewed for all study subjects. RESULTS: Of 1574 deceased study subjects, 12 cases were classified as pharmaceutical drug poisonings according to the death certificates and 10 according to the medico-legal files. When reviewing all available data sources, 9 subjects (0.57%; 95% confidence interval: 0.20-0.94%) were classified as drug poisonings, corresponding to an incidence of 6.5 (95% confidence interval: 2.3-10.7) per 100,000 person-years in the general population. The drug groups most often implicated were benzodiazepines (33%), antihistamines (33%) and analgesics (22%). CONCLUSION: Fatal drug poisonings is a relatively common cause of death in Sweden. By using multiple sources of information when investigating the proportion of fatal poisonings in a population, more accurate estimates may be obtained.

Metformin - Postmortem fatal and non-fatal reference concentrations in femoral blood and risk factors associated with fatal intoxications.

BACKGROUND & OBJECTIVES: To improve the interpretation of fatal intoxications by establishing fatal and non-fatal reference concentrations of metformin in postmortem femoral blood and to further evaluate risk factors associated with fatal metformin intoxication. METHODS: All forensic autopsies in Sweden where metformin was detected in femoral blood 2011-2016 were identified in the National Board of Forensic Medicine databases (NFMD). The cases were classified as single substance intoxications, A (n = 22), multiple substance intoxications, B (N = 7) and postmortem controls, C (N = 13). The control group consisted of cases where metformin was detected, but the cause of death excluded the incapacitation by metformin or other substances. Strict inclusion criteria were used, and all postmortem cases were assessed by two independent reviewers. All other cases where the inclusion criteria of groups A-C where not met formed group O (N = 78). The forensic findings logged in the NFMD where linked to national registers whereby information on comorbidities, dispensed drugs and clinical data could be obtained. RESULTS: The mean age was 66 ± 10 years in the total study population and did not differ between the groups. The proportion of men was 64% in group A, 71% in B, 77% in C and 74% in group O. The median values of metformin in group A (48.5 µg/g; range 13.0-210 µg/g) and B (21.0 µg/g; range 4.40-95.0 µg/g) were significantly (p < 0.001 and p = 0.015 respectively) higher than those of the control group C (2.30 µg/g ; range 0.70-21.0 µg/g). The median concentration of metformin in group A and B was also significantly higher than in group O (4.60 µg/g; range 0.64-54.0 µg/g) (p < 0.001 and p = 0.040 respectively). The results suggest that intoxication with metformin as a cause of death should be considered when the postmortem femoral blood level exceeds about 10 µg/g, although higher levels may be seen in postmortem in cases without incapacitation. The metformin intoxication was confirmed to be intentional in 23% (n = 5) of the single intoxications. Underlying factors identified as important for the remaining fatal metformin intoxications included living alone, any contraindication for the use of metformin, known alcohol abuse and a history of stroke or cardiovascular disease. CONCLUSIONS: The reported post mortem femoral blood concentrations of metformin can hopefully contribute to a better interpretation of results in suspected poisonings and obscure cases. Living in a single household, history of cardiovascular disease and contraindications, predominantly alcohol abuse, were associated with fatal metformin intoxication.