Individuals Dying of Overdoses Related to Pharmaceutical Opioids Differ from Individuals Dying of Overdoses Related to Other Substances: A Population-Based Register Study

Background: Pharmaceutical opioid (PO) overdose deaths have increased in many Western countries. There are indications that those dying from a PO overdose differ from those dying from other types of overdoses. These differences might pose a challenge as the majority of current preventive measures are tailored toward those with the characteristics of "conventional" overdose deaths. Objective: We investigated differences in the characteristics of persons who died from PO overdoses compared to all other overdoses. Material and methods: Using the Norwegian Cause of Death Registry, we retrieved information on overdoses classified according to ICD-10 and identified PO overdoses (T40.2; T40.4) and all other overdoses (T40.X; T43.6) in 2010-2019. By linking data from nationwide registers, we analyzed data on opioid dispensations and the history of mental and behavioral disorders. 1,224 persons were registered with PO overdoses and 1,432 persons with other overdoses. Results: Persons in the PO overdose group were older and were more frequently women (35.0% vs. 20.5%) than persons with other overdoses. They had a higher prevalence of chronic pain (35.8% vs. 13.2%), history of cancer (8.1% vs. 1.8%), filled prescriptions of analgetic opioids more frequently the month before death (38.8% vs. 12.0%), and used threefold higher doses of prescribed opioids compared to individuals in all other overdose group (66 vs. 26 oral morphine equivalents/day). In the PO overdose group, oxycodone and fentanyl were more frequently dispensed, while codeine was more frequently dispensed in the other overdose groups. A lower proportion of those in the PO overdose group had recorded diagnoses of substance use disorders, schizophrenia, and hyperkinetic disorder compared to the other overdose groups. Conclusion: Persons dying from overdoses on POs often differ from the population targeted by existing prevention strategies, as they are more frequently older women with chronic pain and using high doses of prescription opioids.publishedVersio

Prenatal opioid exposure and risk of asthma in childhood: a population-based study from Denmark, Norway, and Sweden

Background: Opioids may modulate the immune function through opioid receptors on immune cells. Long-term consequences of prenatal opioid exposure on the immune system, such as childhood asthma, are unknown.Objectives: To investigate whether prenatal opioid exposure is associated with the risk of childhood asthma.Methods: Cohort study using linked nationwide registers in Denmark (1996–2015), Norway (2005–2015), and Sweden (2006–2013). Children born by mothers who were chronic opioid analgesics users before pregnancy (n = 14,764) or who were receiving opioid maintenance therapy (OMT) before or during pregnancy (n = 1,595) were identified based on information from each of the medical birth registers and prescription registers. Long-term opioid analgesics exposed children were compared to short-term exposed or unexposed, whereas OMT exposed children were compared to OMT unexposed. Asthma among children ≥1 years of age was defined as two or more filled prescriptions of antiasthmatic medication within 365 days, or a diagnosis of asthma. Hazard ratios (HRs) were calculated using Cox proportional hazards regression with attained age as the time scale. Inverse probability of treatment weights based on propensity scores were applied to adjust for measured confounders. Individual level data from Norway and Sweden were pooled, whereas individual level data from Denmark were analyzed separately. For the opioid analgesics comparisons, adjusted HRs (aHR) from the combined Norwegian/Swedish data and the Danish data were pooled in a fixed-effects meta-analysis.Results: For the opioid analgesics cohort, no increased risk of asthma was observed in long-term exposed children neither compared with unexposed [aHR = 0.99 (95% CI 0.87-1.12)], nor compared with short-term exposed [aHR = 0.97 (0.86-1.10)]. No increased risk of asthma was observed in OMT exposed compared with OMT unexposed children [Norway/Sweden: aHR = 1.07 (0.60-1.92), Denmark: aHR = 1.25 (0.87-1.81)]. Results from sensitivity analyses, where potential misclassification of the outcome and misclassification of OMT exposure were assessed, as well as starting follow-up at 6 years of age, showed that the estimates of association were generally robust.Conclusion: We found no association between prenatal exposure to opioids and risk of childhood asthma. Results were consistent across two different opioid exposure groups with different confounder distributions

On the path towards universal coverage of hepatitis C treatment among people receiving opioid agonist therapy (OAT) in Norway: A prospective cohort study from 2013 to 2017

Objectives We aimed to calculate cumulative hepatitis C virus (HCV) treatment coverage among individuals enrolled in opioid agonist therapy (OAT) in Norway between 2013 and 2017 and to document the treatment transition to direct-acting antiviral (DAA) agents. Moreover, we aimed to describe adherence to DAAs in the same cohort. Design Prospective cohort, registry data. Setting Specialist healthcare service (secondary) Participants and outcomes This observational study was based on data from The Norwegian Prescription Database. We studied dispensed OAT and HCV treatment annually to calculate the cumulative frequency, and employed secondary sources to calculate prevalence, incidence and HCV treatment coverage from 2013 to 2017, among the OAT population. Factors associated with adherence to DAAs were identified a priori and subject to logistic regression. Results 10 371 individuals were identified with dispensed OAT, 1475 individuals of these were identified with dispensed HCV treatment. Annual HCV treatment coverage increased from 3.5% (95% CI: 3.2 to 4.4) in 2013 to 17% (95% CI: 17 to 20) in 2017, giving a cumulative HCV coverage among OAT patients in Norway of 38.5%. A complete shift to interferon-free treatment regimens occurred, where DAAs accounting for 32% of HCV treatments in 2013 and 99% in 2017. About two-thirds of OAT patients were considered adherent to their DAA regimens across all genotypes. High level of OAT continuity was associated with improved adherence to DAAs (adjusted OR 1.4, 95% CI: 1 to 2, p=0.035). Conclusions A large increase in HCV treatment coverage attributed by a complete shift to interferon-free regimens among the Norwegian OAT population has been demonstrated. However, treatment coverage is inadmissibly too low and a further substantial scale-up in HCV treatment is required to reach the universal targets of controlling and eliminating the HCV endemic.publishedVersio

Prenatal exposure to pregabalin, birth outcomes and neurodevelopment - a population-based cohort study in four Nordic countries

Introduction: Pregabalin is an antiepileptic drug frequently prescribed to pregnant women. Risks of adverse birth and postnatal neurodevelopmental outcomes following prenatal exposure to pregabalin are uncertain. Objective: To investigate the association between prenatal exposure to pregabalin and the risks of adverse birth and postnatal neurodevelopmental outcomes. Methods: This study was conducted using population-based registries in Denmark, Finland, Norway, and Sweden (2005–2016). We compared pregabalin exposure against no exposure to antiepileptics and against active comparators lamotrigine and duloxetine. We obtained pooled propensity score-adjusted estimates of association using fixed-effect and Mantel–Haenszel (MH) meta-analyses. Results: The total number of pregabalin-exposed births was 325/666,139 (0.05%) in Denmark, 965/643,088 (0.15%) in Finland, 307/657,451 (0.05%) in Norway, and 1275/1,152,002 (0.11%) in Sweden. The adjusted prevalence ratios (aPRs) with 95% confidence interval (CI) following pregabalin exposure versus no exposure were 1.14 (0.98–1.34) for major congenital malformations and 1.72 (1.02–2.91) for stillbirth, which attenuated to 1.25 (0.74–2.11) in MH meta-analysis. For the remaining birth outcomes, the aPRs were close to or attenuated toward unity in analyses using active comparators. Adjusted hazard ratios (95% CI) contrasting prenatal pregabalin exposure versus no exposure were 1.29 (1.03–1.63) for ADHD and attenuated when using active comparators, 0.98 (0.67–1.42) for autism spectrum disorders, and 1.00 (0.78–1.29) for intellectual disability. Conclusions: Prenatal exposure to pregabalin was not associated with low birth weight, preterm birth, small for gestational age, low Apgar score, microcephaly, autism spectrum disorders, or intellectual disability. On the basis of the upper value of the 95% confidence interval, increased risks greater than 1.8 were unlikely for any major congenital malformation and ADHD. For stillbirth and most groups of specific major congenital malformations, the estimates attenuated in MH meta-analysis.publishedVersio

Cardiovascular Safety of Prucalopride in Patients with Chronic Constipation:A Multinational Population-Based Cohort Study

INTRODUCTION: The serotonin 5-HT4 receptor agonist prucalopride is approved in the European Union for the treatment of chronic constipation. This offered the unique opportunity to include real-world observational data on cardiovascular safety in the new drug application for approval of prucalopride in the USA. METHODS: This observational population-based cohort study (EUPAS9200) conducted in five data sources (three in the UK, one in Sweden, and one in Germany [which was subsequently excluded from the pooled analyses]) aimed to estimate the pooled adjusted incidence rate ratio for major adverse cardiovascular events (defined as hospitalization for non-fatal acute myocardial infarction or stroke, and in-hospital cardiovascular death) in adult initiators of prucalopride compared with initiators of polyethylene glycol 3350 (PEG) following a common protocol. Standardized incidence rates and incidence rate ratios of major adverse cardiovascular events were derived using propensity score stratification. Sensitivity analyses explored the impact of exposure definition, outcome categories, interim cancer, and unmeasured confounding. RESULTS: The pooled analyses included 5715 initiators of prucalopride and 29,372 initiators of PEG. Average duration of use was 175 days for prucalopride and 82 days for PEG. The pooled standardized incidence rate per 1000 person-years (95% confidence interval) of major adverse cardiovascular events was 6.57 (3.90–10.39) for patients initiating prucalopride and 10.24 (6.97–14.13) for PEG. The pooled adjusted incidence rate ratio for major adverse cardiovascular events was 0.64 (95% confidence interval 0.36–1.14). Results remained consistent in various sensitivity analyses. CONCLUSIONS: The pooled incidence rate ratio estimate was consistent with no indication of an increased risk above the pre-specified safety threshold of 3.00 for major adverse cardiovascular events in patients with chronic constipation using prucalopride as compared with PEG

An Easy-To-Use Simulation Program Demonstrates Variations in Bacterial Cell Cycle Parameters Depending on Medium and Temperature

Many studies are performed on chromosome replication and segregation in Escherichia coli and other bacteria capable of complex replication with C phases spanning several generations. For such investigations an understanding of the replication patterns, including copy numbers of origins and replication forks, is crucial for correct interpretation of the results

A Reduction in Ribonucleotide Reductase Activity Slows Down the Chromosome Replication Fork but Does Not Change Its Localization

BACKGROUND:It has been proposed that the enzymes of nucleotide biosynthesis may be compartmentalized or concentrated in a structure affecting the organization of newly replicated DNA. Here we have investigated the effect of changes in ribonucleotide reductase (RNR) activity on chromosome replication and organization of replication forks in Escherichia coli. METHODOLOGY/PRINCIPAL FINDINGS:Reduced concentrations of deoxyribonucleotides (dNTPs) obtained by reducing the activity of wild type RNR by treatment with hydroxyurea or by mutation, resulted in a lengthening of the replication period. The replication fork speed was found to be gradually reduced proportionately to moderate reductions in nucleotide availability. Cells with highly extended C periods showed a "delay" in cell division i.e. had a higher cell mass. Visualization of SeqA structures by immunofluorescence indicated no change in organization of the new DNA upon moderate limitation of RNR activity. Severe nucleotide limitation led to replication fork stalling and reversal. Well defined SeqA structures were not found in situations of extensive replication fork repair. In cells with stalled forks obtained by UV irradiation, considerable DNA compaction was observed, possibly indicating a reorganization of the DNA into a "repair structure" during the initial phase of the SOS response. CONCLUSION/SIGNIFICANCE:The results indicate that the replication fork is slowed down in a controlled manner during moderate nucleotide depletion and that a change in the activity of RNR does not lead to a change in the organization of newly replicated DNA. Control of cell division but not control of initiation was affected by the changes in replication elongation

Comparative Safety of Antiseizure Medication Monotherapy for Major Malformations

Funding Information: The study was partly supported by the NordForsk Nordic Program on Health and Welfare (Nordic Pregnancy Drug Safety Studies, project No. 83539 and SCAN‐AED, project No. 83796), by the Research Council of Norway (International Pregnancy Drug Safety Studies, project No. 273366), and by the Research Council of Norway through its Centers of Excellence funding scheme (project No. 262700). H.Z. was supported by a UNSW Scientia Program Award during the conduct of the study. Publisher Copyright: © 2022 The Authors. Annals of Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.Objective: This study was undertaken to examine the comparative safety of antiseizure medication (ASM) monotherapy in pregnancy with respect to risk of major congenital malformations (MCMs), overall and by MCM subtype. Methods: We conducted a population-based cohort study using national health register data from Denmark, Finland, Iceland, Norway, and Sweden (1996–2020). We compared pregnancies with first trimester exposure to lamotrigine monotherapy to ASM-unexposed, carbamazepine, valproate, oxcarbazepine, levetiracetam, and topiramate to lamotrigine monotherapy, and stratified monotherapy groups by dose. The outcome was nongenetic MCM and specific subtypes. We estimated adjusted risk ratios (aRRs) and 95% confidence intervals (CIs) with log-binomial regression and propensity score weights. Results: There was a higher crude risk of any MCM in pregnancies exposed to lamotrigine monotherapy (n = 8,339) compared to ASM-unexposed pregnancies (n = 4,866,362), but not after confounder adjustment (aRR = 0.97, 95% CI = 0.87–1.08). Compared to lamotrigine, there was an increased risk of malformations associated with valproate (n = 2,031, aRR = 2.05, 95% CI = 1.70–2.46) and topiramate (n = 509, aRR = 1.81, 95% CI = 1.26–2.60), which increased in a dose-dependent manner. We found no differences in malformation risk for carbamazepine (n = 2,674, aRR = 0.91, 95% CI = 0.72–1.15), oxcarbazepine (n = 1,313, aRR = 1.09, 95% CI = 0.83–1.44), or levetiracetam (n = 1,040, aRR = 0.78, 95% CI = 0.53–1.13). Valproate was associated with several malformation subtypes, including nervous system, cardiac, oral clefts, clubfoot, and hypospadias, whereas lamotrigine and carbamazepine were not. Interpretation: Topiramate is associated with an increased risk of MCM similar to that associated with valproate, but lower doses may mitigate the risks for both drugs. Conversely, we found no increased risks for lamotrigine, carbamazepine, oxcarbazepine, or levetiracetam, which is reassuring. ANN NEUROL 2022.Peer reviewe

Characterization of the roles of the Escherichia coli SeqA protein in vivo and in vitro by studying two different mutant SeqA proteins

The Escherichia coli SeqA protein, a negative regulator of chromosomal DNA replication, prevents the overinitiation of replication within one cell cycle by binding to hemimethylated GATC sequences in the replication origin, oriC. This process is termed sequestration. Lack of SeqA causes asynchronous initiation because of overinitiation. Binding of SeqA to hemimethylated GATC sequences may also be involved in segregating replicated chromosomes for cell division. SeqA has been found to affect DNA topology in vitro and this indicates that it might have a role in organizing DNA. In vivo, SeqA foci are formed that consist of SeqA proteins cooperatively bound to the newly formed hemimethylated DNA right behind the replication forks. Structural analysis has revealed that the SeqA protein consists of a DNA binding C terminal domain and an N terminal domain with self- association activity. In order to understand more about the roles of SeqA protein in DNA replication and chromosome organization, two different sequestration deficient mutants, seqA3 and seqA4, with mutations in the C terminal and N terminal domain, respectively, were studied. The two mutants were studied in vivo by flow cytometry and immunostaining followed by fluorescence microscopy. Both mutants were found to have an asynchronous phenotype and none of them were able to form discrete fluorescent foci. The SeqA4 protein was purified as a His- tagged protein for in vitro studies. Gel filtration analysis showed that the molecular weight of the SeqA4 mutant protein was close to a tetramer, and that it lacked the wild type property of forming higher order structures with increasing concentration. This indicates that the N terminal domain is necessary for formation of higher order structures. Gel retardation assays showed that the mutant bound hemimethylated oriC as efficiently as wild type SeqA, but with a less cooperative binding pattern than wild type protein. The binding specificity for hemimethylated GATC sites was thus retained in the SeqA4 mutant protein. It was also able to bind to fully methylated oriC, but to a lesser degree and at a much higher concentration of protein compared to wild type SeqA. Supercoiling assays showed that wild type SeqA and the SeqA4 mutant protein affect plasmid topology differently. The SeqA4 mutant protein was capable of restraining fewer negative supercoils in a supercoiled plasmid than wild type SeqA. It was capable of introducing supercoils into a relaxed plasmid at the same level as wild type SeqA. These results show that SeqA binding specificity and higher order oligomerization must both be intact for the formation of "DNA organizing" foci as well as for prevention or re- initiation