Health care service utilization and drug overdose death: A national nested case-control registry study.

Background And Objectives: More knowledge is needed to identify and reach those at overdose risk with preventive measures. We examined past 12-month health service utilization, identified the most frequently utilized service, explored this utilization in more detail, and examined correlates of overdose death.

Methods: A population-based nested case-control registry study including all drug overdose deaths (1 January 2010 to 31 December 2018) in Norway through the Cause of Death Registry (n = 2388).

Patterns of filled prescriptions and the association with risk of drug-induced death. A population-based nested case-control register study.

Purpose: Opioid analgesics (OA) and other pharmaceuticals have been associated with drug-induced deaths. However, there is a lack of knowledge regarding patterns of use of these pharmaceuticals in the population and regarding such associations. We identify and describe subgroups of people with different patterns of filled prescriptions of OA and other relevant pharmaceuticals and examine associations with drug-induced deaths.

No decline in drug overdose deaths in Norway: An ecological approach to understanding at-risk groups and the impact of interventions.

This Norwegian case study examines groups at risk of drug overdose deaths, evidence-based harm reduction interventions, low-threshold services and treatment implemented, as well as trends in drug overdose deaths between 2010 and 2021. We aimed to explore the relevance of interventions for at-risk groups and discuss their potential impact on drug overdose trends. Using an ecological approach, we analysed the following: (1) groups identified through latent profile analysis (LPA) among a sample of 413 high-risk drug users collected in 2010-2012, supplemented with other relevant studies up to 2021; (2) published information on harm-reduction interventions, low-threshold services and treatment in Norway; and (3) nationwide drug overdose mortality figures supplemented with published articles on the topic.

Key Interpretation Challenges for Wastewater-Based Epidemiology of Illicit Drugs: A Norwegian Three-City Case Study.

Introduction: Wastewater-based epidemiology (WBE) has emerged as a timely, non-invasive, and cost-effective indicator of illicit drug consumption. It is increasingly used by international organizations as a proxy measure for estimates of drug prevalence and related trends. Nevertheless, the literature exploring the limitations of WBE remains limited.

Patients admitted to treatment for substance use disorder in Norway: a population-based case-control study of socio-demographic correlates and comparative analyses across substance use disorders.

Background: Improved knowledge regarding socio-demographic correlates of people with substance use disorders (SUDs) is essential to better plan and provide adequate services for SUD patients and their families, and to improve our understanding of the complex mechanisms underlying progression into and development of various SUDs. This study aimed to: i) describe demographic, economic, and social correlates of people with SUDs in comparison with those of the general population and ii) compare these correlates across SUDs from licit versus illicit substances, as well as across specific SUDs.

Methods: A national population-based case-control study included all SUD patients enrolled in specialized drug treatment in Norway in 2009-2010 (N = 31 245) and a population control sample, frequency-matched on age and gender (N = 31 275).

Socio-economic differences in all-cause mortality in people with alcohol use disorder: a prospective cohort study.

Background And Aims: While alcohol-attributable mortality rates are higher in low socio-economic status (SES) groups, less is known about SES differences in all-cause mortality in alcohol use disorder (AUD). The aim of this study was to explore whether there are SES differences in people with AUD, regarding (i) treatment admission, (ii) all-cause mortality risk and (iii) relative mortality risk.

Design And Setting: A prospective cohort study in Norway, follow-up period from 2009-10 to 2013.

A comparison of trends in wastewater-based data and traditional epidemiological indicators of stimulant consumption in three locations.

Aims: To compare long-term trends in wastewater data with other indicators of stimulant use in three locations and to test the reliability of estimates based on 1 week of sampling.

Design: Comparison of trends in quantities ('loads') of stimulants or their metabolites in wastewater with trends in other indicators of stimulant use (e.g.

Economic Evaluation of Direct-Acting Antivirals for Hepatitis C in Norway.

Purpose: New direct-acting antiviral (DAA) drugs have revolutionized the treatment of hepatitis C in recent years.

Objective: Our objective was to analyse the cost effectiveness of combinations of different DAAs compared with ribavirin and peginterferon-α-2a, taking into account rebates from tender negotiations.

Methods: We used a compartmental model specifically developed for Norway to simulate hepatitis C and complications with and without different DAAs.

Modelling the burden of hepatitis C infection among people who inject drugs in Norway, 1973-2030.

Background: Lack of Hepatitis C virus (HCV) incidence data in (Norwegian) high-risk groups impedes the ability to make informed decisions on prevention measures. Thus we rely on modelling to estimate the incidence and burden of HCV infections.

Methods: We constructed a compartmental model for HCV infections in Norway among active and former people who inject drugs (PWIDs).

Lack of overlap and large discrepancies in the characteristics of the deceased in two sources of drug death. A linkage study of the Cause of Death and the Police Registries in Norway 2007-2009.

Background: Registries for drug deaths may include different persons and provide different characteristics of the deceased. The aim of this study was to establish whether a database of drug-induced deaths (Cause of Death Registry (CDR) using the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) definition and the Police registry of drug deaths) included the same persons and provided the same characteristics of the deceased and thus yielded the same information for establishing targeted prevention measures.

Methods: Notifications from 2007 to 2009 were drawn from the CDR and the police registry of drug deaths and the unique Norwegian personal identification number was used to match the registrations.

Estimating incidence of problem drug use using the Horwitz-Thompson estimator - A new approach applied to people who inject drugs in Oslo 1985-2008.

Background: The trend in the number of new problem drug users per year (incidence) is the most important measure for studying the diffusion of problem drug use. Due to sparse data sources and complicated statistical models, estimation of incidence of problem drug use is challenging. The aim of this study is to widen the palette of available methods and data types for estimating incidence of problem drug use over time, and for identifying the trends.

Changes in mortality due to major alcohol-related diseases in four Nordic countries, France and Germany between 1980 and 2009: a comparative age-period-cohort analysis.

Aims: To investigate age, period and cohort effects on time trends of alcohol-related mortality in countries with different drinking habits and alcohol policies.

Design And Setting: Age-period-cohort (APC) analyses on alcohol-related mortality were conducted in Denmark, Finland, Norway, Sweden, France and Germany.

Participants: Cases included alcohol-related deaths in the age range 20-84 years between 1980 and 2009.

Drug-related causes of death: Socioeconomic and demographic characteristics of the deceased.

Aim: The aim of this study was to describe subgroups of those who died from a drug-related cause of death employing demographic and socioeconomic data.

Methods: A total of 1,628 persons with registered drug-related deaths in the Norwegian Cause of Death Registry between 2003 and 2009 were matched with research registers of data on demographic and socioeconomic factors during the five years prior to their deaths.

Results: Three equal-sized clusters were identified: persons with very low socioeconomic status, disability pensioners and people on the edge of the workforce.

HCV treatment uptake in people who have injected drugs - observations in a large cohort that received addiction treatment 1970-1984.

Objectives: The aim of this study was to document antiviral treatment uptake among former or current people who inject drugs (PWID) with chronic hepatitis C and to explore a possible association between treatment and mortality.

Material And Methods: This is a longitudinal cohort study of PWID admitted for drug abuse treatment 1970-1984. The 245 hepatitis C virus (HCV) RNA-positive patients alive by the end of 1996 were followed 1997-2012 through linkage to several health registers.

Self-reports of consumption of amphetamines, cocaine and heroin in a survey among marginalized drug users.

Background And Aim: Scientific literature offers few measurements of the quantities consumed by individual drug users. Such measurements are used for calculating the total drug consumption by the quantity-frequency method, and are extremely important for the comparison with waste water derived consumption estimates. The aim of this study was to measure quantities of amphetamines, cocaine and heroin consumed by marginalized drug users, using a multi-city questionnaire survey design.

Liver fibrosis progression at autopsy in injecting drug users infected by hepatitis C: a longitudinal long-term cohort study.

Background & Aims: There is a paucity of unbiased data on the natural history of hepatitis C virus (HCV) infection in injecting drug users (IDUs). The purpose of this study was to assess the risk of developing advanced fibrosis associated with chronic hepatitis C (CHC) infection among injecting drug users (IDUs) who underwent an autopsy.

Methods: A longitudinal cohort design was applied, in which the stage of liver fibrosis in anti-HCV positive IDUs with or without chronic HCV infection was assessed in liver tissue from autopsies performed up to 35 years after HCV exposure.

A multi-state model to estimate incidence of heroin use.

Background: Existing incidence estimates of heroin use are usually based on one information source. This study aims to incorporate more sources to estimate heroin use incidence trends in Spain between 1971 and 2005.

Methods: A multi-state model was constructed, whereby the initial state "heroin consumer" is followed by transition to either "admitted to first treatment" or to "left heroin use" (i.

Estimation of cocaine consumption in the community: a critical comparison of the results from three complimentary techniques.

Objectives: A range of approaches are now available to estimate the level of drug use in the community so it is desirable to critically compare results from the differing techniques. This paper presents a comparison of the results from three methods for estimating the level of cocaine use in the general population.

Design: The comparison applies to; a set of regional-scale sample survey questionnaires, a representative sample survey on drug use among drivers and an analysis of the quantity of cocaine-related metabolites in sewage.

All-cause and liver-related mortality in hepatitis C infected drug users followed for 33 years: a controlled study.

Background & Aims: The course of chronic hepatitis C virus (HCV) in injecting drug users (IDUs) has not been well described. The aim of this study was to compare long-term all-cause and liver-related mortality among anti-HCV positive IDUs with and without persisting HCV infection.

Methods: A retrospective-prospective controlled cohort design was applied.

Low level of alcohol drinking among two generations of non-Western immigrants in Oslo: a multi-ethnic comparison.

Background: Alcohol drinking is a risk factor for harm and disease. A low level of drinking among non-Western immigrants may lead to less alcohol-related harm and disease. The first aim of this study was to describe frequency of drinking in two generations of immigrants in Oslo, contrasting the result to drinking frequency among ethnic Norwegians.

A method to estimate total entry to hard drug use: the case of intravenous drug use in Norway.

Background/aims: Epidemiological measures such as the prevalence and incidence of hard drug use are important tools for evaluating drug situations and drug policies. Models for drug use trajectories illustrate how temporary and lasting cessation of and relapse into hard drug use are other important elements in the overall picture of change in hard drug use over time. Estimating the total entry to hard drug use broadens the knowledge of the change in such use.

Mortality among drug users after discharge from inpatient treatment: an 8-year prospective study.

Background: Drug users who are leaving/completing inpatient medication-free treatment may, like drug users released from prison, have an elevated risk of dying from fatal overdoses. This is mainly explained by their low drug tolerance.

Methods: Two hundred and seventy-six drug users who had been admitted to 11 inpatient facilities in Norway, were followed prospectively after discharge from treatment during an 8-year period (1998-2006).

Growth rates in epidemic models: application to a model for HIV/AIDS progression.

The most common quantity used to describe the growth of an epidemic when modelling infectious diseases is the basic reproduction number R0. While R0 is most appropriate for epidemics with short-lasting infections, long-lasting infections such as HIV/AIDS may call for the use of growth rates with other properties. For a group of multi-state compartment models we define both R0, the actual reproduction number Ra(t), and the intrinsic growth rate r.

Fatal overdoses and deaths by other causes in a cohort of Norwegian drug abusers--a competing risk approach.

Objective: To identify causes of death among Norwegian drug abusers and to investigate the risk factors for fatal overdose and other causes of death, with specific attention to ageing and duration of abuse.

Methods: In a cohort of 501 drug abusers admitted to treatment in the period 1981-1991, mortality has been calculated as incidence rates. The analyses of time to death were conducted as proportional hazard regression models using a competing risk approach.