The impact of blood-borne viruses on cause-specific mortality among opioid dependent people: An Australian population-based cohort study

Factors associated with suicide in people who use drugs: a scoping review

BACKGROUND

Suicide is a significant contributor to global mortality. People who use drugs (PWUD) are at increased risk of death by suicide relative to the general population, but there is a lack of information on associated candidate factors for suicide in this group. The aim of this study was to provide a comprehensive overview of existing evidence on potential factors for death by suicide in PWUD.

METHODS

A scoping review was conducted according to the Arksey and O'Malley framework. Articles were identified using Medline, CINAHL, PsycINFO, SOCIndex, the Cochrane Database of Systematic Reviews and the Campbell Collaboration Database of Systematic Reviews; supplemented by grey literature, technical reports, and consultation with experts. No limitations were placed on study design. Publications in English from January 2000 to December 2021 were included. Two reviewers independently screened full-text publications for inclusion. Extracted data were collated using tables and accompanying narrative descriptive summaries. The review was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines.

RESULTS

The initial search identified 12,389 individual publications, of which 53 met the inclusion criteria. The majority (87%) of included publications were primary research, with an uncontrolled, retrospective study design. The most common data sources were drug treatment databases or national death indexes. Eleven potential factors associated with death by suicide among PWUD were identified: sex; mental health conditions; periods of heightened vulnerability; age profile; use of stimulants, cannabis, or new psychoactive substances; specific medical conditions; lack of dual diagnosis service provision; homelessness; incarceration; intravenous drug use; and race or ethnicity. Opioids, followed by cannabis and stimulant drugs were the most prevalent drugs of use in PWUD who died by suicide. A large proportion of evidence was related to opioid use; therefore, more primary research on suicide and explicit risk factors is required.

CONCLUSIONS

The majority of studies exploring factors associated with death by suicide among PWUD involved descriptive epidemiological data, with limited in-depth analyses of explicit risk factors. To prevent suicide in PWUD, it is important to consider potential risk factors and type of drug use, and to tailor policies and practices accordingly.

Effect of HCV or HIV infection on mortality among hospitalized persons who used opioids, 2000-2010

Mortality due to opioid misuse and overdose has increased substantially in the United States over the past two decades. The study objective was to describe the causes of death among persons with opioid-related hospitalizations and examine survival by Hepatitis C virus (HCV) or HIV. Opioid-related hospitalization records in Pennsylvania from 2000 to 2010 were linked to death registry files to assess cause of death, and survival from first hospital discharge date to death date, or December 31, 2010. Accelerated failure time models were used to compare survival between persons with and without HCV or HIV diagnoses. Among the 136,416 individuals with an opioid-related hospitalization, 13.0% died over a median of 56 months of follow-up; the most common causes of death were circulatory diseases (26.4%) and drug overdose (23.5%). There were 27,122 (19.9%) and 3662 (2.7%) persons who had an HCV and HIV diagnosis, respectively. Among patients aged ≥20 years, those with HCV had shorter survival time compared to those without HCV, with discrepancies more pronounced at older ages. Patients with HIV also had shorter survival time (time ratio: 0.29 [95% CI: 0.26, 0.34]) compared to without HIV. These findings show that in a cohort of patients with opioid-related hospitalizations, those with HCV or HIV diagnoses have shorter survival. This has public health implications, providing further evidence that medical providers should educate patients who use opioids about the risks of HCV and HIV infection and focus prevention and treatment to decrease mortality among patients hospitalized for opioid use.

Bayesian network modelling study to identify factors influencing the risk of cardiovascular disease in Canadian adults with hepatitis C virus infection

OBJECTIVES

The present study evaluates the extent of association between hepatitis C virus (HCV) infection and cardiovascular disease (CVD) risk and identifies factors mediating this relationship using Bayesian network (BN) analysis.

DESIGN AND SETTING

A population-based cross-sectional survey in Canada.

PARTICIPANTS

Adults from the Canadian Health Measures Survey (n=10 115) aged 30 to 74 years.

PRIMARY AND SECONDARY OUTCOME MEASURES

The 10-year risk of CVD was determined using the Framingham Risk Score in HCV-positive and HCV-negative subjects. Using BN analysis, variables were modelled to calculate the probability of CVD risk in HCV infection.

RESULTS

When the BN is compiled, and no variable has been instantiated, 73%, 17% and 11% of the subjects had low, moderate and high 10-year CVD risk, respectively. The conditional probability of high CVD risk increased to 13.9%±1.6% (p<2.2×10^-16) when the HCV variable is instantiated to 'Present' state and decreased to 8.6%±0.2% when HCV was instantiated to 'Absent' (p<2.2×10^-16). HCV cases had 1.6-fold higher prevalence of high-CVD risk compared with non-infected individuals (p=0.038). Analysis of the effect modification of the HCV-CVD relationship (using median Kullback-Leibler divergence; D_KL ) showed diabetes as a major effect modifier on the joint probability distribution of HCV infection and CVD risk (D_KL =0.27, IQR: 0.26 to 0.27), followed by hypertension (0.24, IQR: 0.23 to 0.25), age (0.21, IQR: 0.10 to 0.38) and injection drug use (0.19, IQR: 0.06 to 0.59).

CONCLUSIONS

Exploring the relationship between HCV infection and CVD risk using BN modelling analysis revealed that the infection is associated with elevated CVD risk. A number of risk modifiers were identified to play a role in this relationship. Targeting these factors during the course of infection to reduce CVD risk should be studied further.

Opioid-related deaths in Europe: Strategies for a comprehensive approach to address a major public health concern

Use of illicit opioids and misuse of prescription opioids are the main causes of drug-related deaths across the world, and the continuing rise in opioid-related mortality, especially affecting North America, Australia and Europe, is a public health challenge. Strategies that may help to decrease the high levels of opioid-related mortality and morbidity and improve care across Europe include risk assessment and interventions to improve the use of opioid analgesics, e.g. prescription drug-monitoring programmes, education on pain management to reduce opioid prescribing, and the implementation of evidence-based primary prevention programmes to reduce the demand for opioids. For patients who develop opioid use disorder (a chronic and relapsing problematic use of opioids that causes clinical impairment or distress), treatment combining opiate receptor full or partial agonist medications for opioid-use disorder (MOUD) with psychosocial interventions is essential. However, in Europe a substantial proportion of the 1.3 million high-risk opioid users (defined as injecting drug use or regular use of opioids, mainly heroin) remain outside of dedicated treatment programmes. More widespread and easier access to MOUD could reduce mortality levels; via approaches such as primary care-led treatment models, and efforts to improve patient retention and adherence to treatment programmes. Other harm-reduction strategies, such as the use of MOUD at optimal doses, the provision of take-home naloxone, the introduction of supervised drug-consumption facilities, and patient education to reduce the risk of overdose may also be beneficial.

Effects of medication-assisted treatment on mortality among opioids users: a systematic review and meta-analysis

Opioid use disorder (OUD) is associated with a high risk of premature death. Medication-assisted treatment (MAT) is the primary treatment for opioid dependence. We comprehensively assessed the effects of different MAT-related characteristics on mortality among those with OUD by a systematic review and meta-analysis. The all-cause and overdose crude mortality rates (CMRs) and relative risks (RRs) by treatment status, different type, period, and dose of medication, and retention time were pooled using random effects, subgroup analysis, and meta-regression. Thirty cohort studies involving 370,611 participants (1,378,815 person-years) were eligible in the meta-analysis. From 21 studies, the pooled all-cause CMRs were 0.92 per 100 person-years (95% CI: 0.79-1.04) while receiving MAT, 1.69 (1.47-1.91) after cessation, and 4.89 (3.54-6.23) for untreated period. Based on 16 studies, the pooled overdose CMRs were 0.24 (0.20-0.28) while receiving MAT, 0.68 (0.55-0.80) after cessation of MAT, and 2.43 (1.72-3.15) for untreated period. Compared with patients receiving MAT, untreated participants had higher risk of all-cause mortality (RR 2.56 [95% CI: 1.72-3.80]) and overdose mortality (8.10 [4.48-14.66]), and discharged participants had higher risk of all-cause death (2.33 [2.02-2.67]) and overdose death (3.09 [2.37-4.01]). The all-cause CMRs during and after opioid substitution treatment with methadone or buprenorphine were 0.93 (0.76-1.10) and 1.79 (1.47-2.10), and corresponding estimate for antagonist naltrexone treatment were 0.26 (0-0.59) and 1.97 (0-5.18), respectively. Retention in MAT of over 1-year was associated with a lower mortality rate than that with retention ≤1 year (1.62, 1.31-1.93 vs. 5.31, -0.09-10.71). Improved coverage and adherence to MAT and post-treatment follow-up are crucial to reduce the mortality. Long-acting naltrexone showed positive advantage on prevention of premature death among persons with OUD.

A review of the use of time-varying covariates in the Fine-Gray subdistribution hazard competing risk regression model

In survival analysis, time‐varying covariates are covariates whose value can change during follow‐up. Outcomes in medical research are frequently subject to competing risks (events precluding the occurrence of the primary outcome). We review the types of time‐varying covariates and highlight the effect of their inclusion in the subdistribution hazard model. External time‐dependent covariates are external to the subject, can effect the failure process, but are not otherwise involved in the failure mechanism. Internal time‐varying covariates are measured on the subject, can effect the failure process directly, and may also be impacted by the failure mechanism. In the absence of competing risks, a consequence of including internal time‐dependent covariates in the Cox model is that one cannot estimate the survival function or the effect of covariates on the survival function. In the presence of competing risks, the inclusion of internal time‐varying covariates in a subdistribution hazard model results in the loss of the ability to estimate the cumulative incidence function (CIF) or the effect of covariates on the CIF. Furthermore, the definition of the risk set for the subdistribution hazard function can make defining internal time‐varying covariates difficult or impossible. We conducted a review of the use of time‐varying covariates in subdistribution hazard models in articles published in the medical literature in 2015 and in the first 5 months of 2019. Seven percent of articles published included a time‐varying covariate. Several inappropriately described a time‐varying covariate as having an association with the risk of the outcome.

Global burden of atherosclerotic cardiovascular disease in people with hepatitis C virus infection: a systematic review, meta-analysis, and modelling study

BACKGROUND

More than 70 million people worldwide are estimated to have hepatitis C virus (HCV) infection. Emerging evidence indicates an association between HCV and atherosclerotic cardiovascular disease. We aimed to determine the association between HCV and cardiovascular disease, and estimate the national, regional, and global burden of cardiovascular disease attributable to HCV.

METHODS

For this systematic review and meta-analysis, we searched MEDLINE, Embase, Ovid Global Health, and Web of Science databases from inception to May 9, 2018, without language restrictions, for longitudinal studies that evaluated the risk ratio (RR) of cardiovascular disease in people with HCV compared with those without HCV. Two investigators independently reviewed and extracted data from published reports. The main outcome was cardiovascular disease, defined as hospital admission with, or mortality from, acute myocardial infarction or stroke. We calculated the pooled RR of cardiovascular disease associated with HCV using a random-effects model. Additionally, we calculated the population attributable fraction and disability-adjusted life-years (DALYs) from HCV-associated cardiovascular disease at the national, regional, and global level. We also used age-stratified and sex-stratified HCV prevalence estimates and cardiovascular DALYs for 100 countries to estimate country-level burden associated with HCV. This study is registered with PROSPERO, number CRD42018091857.

FINDINGS

Our search identified 16 639 records, of which 36 studies were included for analysis, including 341 739 people with HCV. The pooled RR for cardiovascular disease was 1·28 (95% CI 1·18-1·39). Globally, 1·5 million (95% CI 0·9-2·1) DALYs per year were lost due to HCV-associated cardiovascular disease. Low-income and middle-income countries had the highest disease burden with south Asian, eastern European, north African, and Middle Eastern regions accounting for two-thirds of all HCV-associated cardiovascular DALYs.

INTERPRETATION

HCV infection is associated with an increased risk of cardiovascular disease. The global burden of cardiovascular disease associated with HCV infection was responsible for 1·5 million DALYs, with the highest burden in low-income and middle-income countries.

FUNDING

British Heart Foundation and Wellcome Trust.

Mortality among people who inject drugs: Ten-year follow-up of the hepatitis C virus cohort

INTRODUCTION AND AIMS

Mortality studies of people who inject drugs (PWID) are mostly of older people and drug treatment cohorts. We estimate mortality rates, describe causes of death, and years of potential life lost in a community-recruited cohort of young PWID characterised by high incidence of hepatitis C virus (HCV) infection.

DESIGN AND METHODS

Participant identifiers of 215 PWID from the south-western Sydney sub-cohort of the HCV Cohort were linked to National Death Index records from 1999 to 2010 and crude mortality rates and standardised mortality ratios estimated. Australian life tables were used to calculate years of potential of life lost.

RESULTS

Fifteen participants died (7.0%) in 2095 person years (PY) of follow-up. Median age at death was 30.6 years (interquartile range 24.9-32.2). The crude mortality rate was 0.72 per 100PY (95% confidence interval 0.29-0.79) with a standardised mortality ratio of 11.09 (95% confidence interval 6.68-18.39). One-third of deaths were due to accidental drug overdose (5/15) and one-fifth were suicides (3/15). All deaths from defined causes (13/15) were potentially avoidable. Decedents lost on average 49.8 years of potential life.

DISCUSSION AND CONCLUSIONS

Mortality and potential life lost further highlight the impact of accidental overdose deaths and suicide among young PWID. Integration of overdose and suicide prevention into youth-orientated outreach, including innovation in online and mobile technology should be evaluated.

Cardiovascular disease risk in patients with hepatitis C infection: Results from two general population health surveys in Canada and the United States (2007-2017)

The role of hepatitis C virus (HCV) infection in increasing the risk of cardiovascular disease (CVD) is controversial. The objective of the present study is to estimate the 10-year risk of CVD in HCV- positive subjects and describe their profile of cardiometabolic risk markers compared to HCV-negative subjects. We conducted a cross-sectional study to estimate 10-year CVD risk, calculated using the Framingham Risk Score (FRS), in participants from the Canadian Health Measures Survey (CHMS; 2007–2015, n = 10,115) and the US-National Health and Nutrition Examination Survey (NHANES; 2007–2016, n = 16,668). Subjects included in our analysis were aged 30 to 74 years with no prior history of CVD. FRS estimates, sociodemographic and cardiometabolic risk factors were compared between HCV- positive and -negative subjects in the two surveys. HCV-positive subjects had a distinct sociodemographic profile compared to their HCV-negative counterparts. Cardiometabolic risk factors, inflammatory markers and serum levels of micronutrients were comparable between the two survey populations, both in HCV-positive and -negative subjects. The average FRS in HCV-positive patients was in the range of “intermediate” 10-year CVD risk (i.e., 10–20%) and was significantly higher (P<0.01) than their HCV-negative counterparts who were within the “low” 10-year CVD risk range (i.e., ≤10%). Using a multivariable linear regression model adjusted for ethnicity, number of metabolic syndrome components and BMI, HCV infection was significantly associated with a 2.5–3.5% absolute risk increase of 10-year CVD (P<0.01). The results of the present study suggest a potential association between HCV infection and risk of subclinical and clinical CVD. The expansion of anti-HCV therapy may also contribute to reduced CVD risk and burden in patients with chronic HCV infection and should be explored further in other datasets and population modelling studies.

Expert opinion on managing chronic HCV in patients with cardiovascular disease

Extrahepatic manifestations of chronic HCV infection include cardiovascular diseases and an increase in cardiovascular mortality. The pathogenic mechanisms by which HCV contributes to cardiovascular disease are not well defined, however, it is likely that systemic inflammation, and the promotion of other metabolic diseases are involved. In this Review, the evidence for HCV infection as a non-traditional risk factor for cardiovascular disease is evaluated. Furthermore, practical advice to evaluate cardiovascular disease risk and disease in chronic hepatitis C patients are included for help in daily clinical practice. Despite the advances in therapies for the treatment of HCV, there remains a need for increased awareness among specialists so that patients are more likely to obtain the treatment required to mitigate disease progression.

Risk of Cardiovascular Disease Due to Chronic Hepatitis C Infection: A Review

Hepatitis C (HCV) infection has an estimated global prevalence of 2.5%, causing chronic liver disease in 170 million people worldwide. Recent data has identified HCV infection as a risk factor for subclinical and clinical cardiovascular disease (CVD), but these data have been mixed and whether HCV is an independent risk factor for development of CVD remains controversial. In this review, we present the literature regarding the association of HCV with subclinical and clinical CVD and the possible underlying mechanisms leading to increased CVD among those infected with HCV. HCV infection leads to increased CVD via direct and indirect mechanisms with chronic inflammation, endothelial dysfunction and direct invasion of the arterial wall cited as possible mechanisms. Our review showed that HCV infection, particularly chronic HCV infection, appears to lead to increased subclinical CVD most consistently and potentially also to increased clinical CVD outcomes, leading to increased morbidity and mortality. Furthermore, the majority of studies evaluating the impact of HCV therapy on CVD morbidity and mortality showed an improvement in subclinical and clinical CVD endpoints in patients who were successfully treated and achieved sustained viral suppression. These results are of particular interest following the development of new direct antiviral agents which have made HCV eradication simple and feasible for many more patients globally, and in doing so may possibly reduce CVD morbidity and mortality in those with chronic HCV infection.

Cardiovascular Manifestations of Hepatitis C Virus

Hepatitis C virus (HCV) infection is a prevalent condition associated with numerous extrahepatic manifestations. Epidemiologic studies have found that HCV is associated with increased cardiovascular morbidity and mortality, in particular with carotid atherosclerosis, cerebrovascular events, and coronary heart disease. The mechanisms involved encompass a chronic systemic inflammatory state, insulin resistance, and a potential, direct infection of the vascular endothelium. Sustained virologic response with interferon-based regimens is associated with reduced cardiovascular events, although this must be validated with newer direct-acting antivirals. This clear association between HCV and cardiovascular events may have significant economical and public health implications.

The risk of coronary artery disease and cerebrovascular disease in patients with hepatitis C: A systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Some studies suggest that patients with hepatitis C virus (HCV) infection have an increased risk of coronary artery disease (CAD) and cerebrovascular disease. Unfortunately, available data on this association are widely variable. We have performed a systematic review and meta-analysis of literature to evaluate the risk of cardio-cerebrovascular disease (CCD) associated with HCV.

METHODS

Studies reporting on CCD risk associated with HCV were systematically searched in the PubMed, Web of Science, Scopus and EMBASE databases.

RESULTS

Twenty-seven studies (34 data-sets) showed a significantly increased CCD risk in 297,613 HCV patients as compared with 557,814 uninfected controls (OR: 1.428; 95% CI: 1.214, 1.681). These results were confirmed when separately considering the risk of CAD (20 studies, OR: 1.382; 95% CI: 1.103, 1.732) and of cerebrovascular disease (13 studies, OR: 1.485; 95% CI: 1.079, 2.044). Similar results were confirmed when analyzing 21 studies reporting adjusted risk estimates (OR: 1.448; 95% CI: 1.218, 1.722) and when, after excluding studies defining CAD as positive angiographic or electrocardiographic evidence, we specifically included the 17 studies reporting on acute CCD-related events (OR: 1.357; 95% CI: 1.103, 1.670). Moreover, 4 studies evaluating CCD-related deaths showed a higher risk in HCV patients than controls (OR: 1.772; 95% CI: 1.448, 2.168; P<0.0001). Meta-regression models suggested a direct association between prevalence of cirrhosis and difference in CCD risk between HCV patients and controls.

CONCLUSIONS

Results of our large meta-analysis suggest that HCV-infected subjects experience an increased risk of CCD. This should be considered to plan specific cardiovascular prevention strategies in this clinical setting.

Hepatitis C virus and cardiovascular: A review

Chronic hepatitis C virus (HCV) infection is a systemic disease that leads to increased risks of cirrhosis and its complications, as well as extrahepatic disturbances, including immune-related disorders and metabolic alterations such as insulin resistance and steatosis. Recent accumulating evidence suggests that HCV infection can increase cardiovascular risk, and that viral eradication can improve cardiovascular outcomes in the clinical setting. These data are strengthened by evidence identifying potential mechanisms (in)directly linking HCV infection to vascular damage. However, the high prevalence of both HCV infection and cardiovascular alterations, as well as the presence of contrasting results not identifying any association between HCV infection and cardiovascular dysfunction, provides uncertainty about a direct association of HCV infection with cardiovascular risk. Further studies are needed to clarify definitively the role of HCV infection in cardiovascular alterations, as well as the impact of viral eradication on cardiovascular outcomes. These features are now more attractive, considering the availability of new, safe, and very effective interferon-free antiviral agents for the treatment of HCV infection. This review aims to discuss carefully available data on the relationship between HCV infection and cardiovascular risk.

Hepatitis C Virus Infection Is Associated With Increased Cardiovascular Mortality: A Meta-Analysis of Observational Studies

BACKGROUND & AIMS

There have been many studies of the effects of hepatitis C virus (HCV) infection on cardiovascular risk, but these have produced ambiguous results. We performed a meta-analysis of these studies to systematically assess the risk of HCV infection on cardiovascular disease (CVD)-related morbidity and mortality.

METHODS

We searched PubMed Central, Medline, Embase, and Cochrane Library, as well as reference lists of articles, for studies published through July 2015 that compared the occurrence of CVD between HCV-infected and HCV-uninfected subjects, or assessed the prevalence of HCV infection among subjects with CVDs. In total, 22 studies were analyzed. Data on the patient populations and outcomes were extracted from each study by 3 independent observers and combined by a random-effects model.

RESULTS

Compared with uninfected individuals (controls), HCV-infected patients had increased risks of CVD-related mortality (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.07-2.56; P = .02), carotid plaques (OR, 2.27; 95% CI, 1.76-2.94; P < .001), and cerebrocardiovascular events (OR, 1.30; 95% CI, 1.10-1.55; P = .002). Significant heterogeneity was observed in the risk of cerebrocardiovascular disease among individuals with HCV infection. The effect of HCV infection on cerebrocardiovascular disease was stronger in populations with a higher prevalence of diabetes (>10%) or hypertension (>20%) (OR, 1.71; 95% CI, 1.32-2.23; P < .001 for both).

CONCLUSIONS

In a meta-analysis of published studies, individuals with HCV infections were found to be at increased risk for CVD-related morbidity and mortality-especially patients with diabetes and hypertension.