Cause-specific mortality associated with HIV and HTLV-II infections among injecting drug users in the USA

HTLV-2 Enhances CD8+ T Cell-Mediated HIV-1 Inhibition and Reduces HIV-1 Integrated Proviral Load in People Living with HIV-1

People living with HIV-1 and HTLV-2 concomitantly show slower CD4⁺ T cell depletion and AIDS progression, more frequency of the natural control of HIV-1, and lower mortality rates. A similar beneficial effect of this infection has been reported on HCV coinfection reducing transaminases, increasing the spontaneous clearance of HCV infection and delaying the development of hepatic fibrosis. Given the critical role of CD8⁺ T cells in controlling HIV-1 infection, we analysed the role of CD8⁺ T cell-mediated cytotoxic activity in coinfected individuals living with HIV-1. One hundred and twenty-eight individuals living with HIV-1 in four groups were studied: two groups with HTLV-2 infection, including individuals with HCV infection (N = 41) and with a sustained virological response (SVR) after HCV treatment (N = 25); and two groups without HTLV-2 infection, including individuals with HCV infection (N = 25) and with a sustained virological response after treatment (N = 37). We found that CD8⁺ T cell-mediated HIV-1 inhibition in vitro was higher in individuals with HTLV-2. This inhibition activity was associated with a higher frequency of effector memory CD8⁺ T cells, higher levels of granzyme A and granzyme B cytolytic enzymes, and perforin. Hence, cellular and soluble cytolytic factors may contribute to the lower HIV-1 pre-ART viral load and the HIV-1 proviral load during ART therapy associated with HTLV-2 infection. Herein, we confirmed and expanded previous findings on the role of HTLV-2 in the beneficial effect on the pathogenesis of HIV-1 in coinfected individuals.

Neurological Aspects of HIV-1/HTLV-1 and HIV-1/HTLV-2 Coinfection

Simultaneous infection by human immunodeficiency viruses (HIV) and human T-lymphotropic viruses (HTLV) are not uncommon since they have similar means of transmission and are simultaneously endemic in many populations. Besides causing severe immune dysfunction, these viruses are neuropathogenic and can cause neurological diseases through direct and indirect mechanisms. Many pieces of evidence at present show that coinfection may alter the natural history of general and, more specifically, neurological disorders through different mechanisms. In this review, we summarize the current evidence on the influence of coinfection on the progression and outcome of neurological complications of HTLV-1/2 and HIV-1.

Modeling a dynamic bi-layer contact network of injection drug users and the spread of blood-borne infections

Injection drug users (IDUs) are at high risk of acquiring and spreading various blood-borne infections including human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV) and a number of sexually transmitted infections. These infections can spread among IDUs via risky sexual and needle-sharing contacts. To accurately model the spread of such contagions among IDUs, we build a bi-layer network that captures both types of risky contacts. We present methodology for inferring important model parameters, such as those governing network structure and dynamics, from readily available data sources (e.g., epidemiological surveys). Such a model can be used to evaluate the efficacy of various programs that aim to combat drug addiction and contain blood-borne diseases among IDUs. The model is especially useful for evaluating interventions that exploit the structure of the contact network. To illustrate, we instantiate a network model with data collected by a needle and syringe program in Chicago. We model sexual and needle-sharing contacts and the consequent spread of HIV and HCV. We use the model to evaluate the potential effects of a peer education (PE) program under different targeting strategies. We show that a targeted PE program would avert significantly more HIV and HCV infections than an untargeted program, highlighting the importance of reaching individuals who are centrally located in contact networks when instituting prevention programs.

High Mortality Among Non-HIV-Infected People Who Inject Drugs in Bangkok, Thailand, 2005-2012

OBJECTIVES

We examined the causes of hospitalization and death of people who inject drugs participating in the Bangkok Tenofovir Study, an HIV preexposure prophylaxis trial.

METHODS

The Bangkok Tenofovir Study was a randomized, double-blind, placebo-controlled trial conducted during 2005 to 2012 among 2413 people who inject drugs. We reviewed medical records to define the causes of hospitalization and death, examined participant characteristics and risk behaviors to determine predictors of death, and compared the participant mortality rate with the rate of the general population of Bangkok, Thailand.

RESULTS

Participants were followed an average of 4 years; 107 died: 22 (20.6%) from overdose, 13 (12.2%) from traffic accidents, and 12 (11.2%) from sepsis. In multivariable analysis, older age (40-59 years; P = .001), injecting drugs (P = .03), and injecting midazolam (P < .001) were associated with death. The standardized mortality ratio was 2.9.

CONCLUSIONS

People who injected drugs were nearly 3 times as likely to die as were those in the general population of Bangkok and injecting midazolam was independently associated with death. Drug overdose and traffic accidents were the most common causes of death, and their prevention should be public health priorities.

Examining non-AIDS mortality among people who inject drugs

Objective:

To systematically review and analyse data from cohorts of people who inject drugs (PWID) to improve existing estimates of non-AIDS mortality used to calculate mortality among PWID in the Spectrum Estimates and Projection Package.

Design:

Systematic review and meta-analysis.

Methods:

We conducted an update of an earlier systematic review of mortality among PWID, searching specifically for studies providing data on non-AIDS-related deaths. Random-effects meta-analyses were performed to derive pooled estimates of non-AIDS crude mortality rates across cohorts disaggregated by sex, HIV status and periods in and out of opioid substitution therapy (OST). Within each cohort, ratios of non-AIDS CMRs were calculated and then pooled across studies for the following paired sub-groups: HIV-negative versus HIV-positive PWID; male versus female PWID; periods in OST versus out of OST. For each analysis, pooled estimates by country income group and by geographic region were also calculated.

Results:

Thirty-seven eligible studies from high-income countries and five from low and middle-income countries were found. Non-AIDS mortality was significantly higher in low and middle-income countries [2.74 per 100 person-years; 95% confidence interval (CI) 1.76–3.72] than in high-income countries (1.56 per 100 person-years; 95% CI 1.38–1.74). Non-AIDS CMRs were 1.34 times greater among men than women (95% CI 1.14–1.57; N = 19 studies); 1.50 times greater among HIV-positive than HIV-negative PWID (95% CI 1.15, 1.96; N = 16 studies); and more than three times greater during periods out of OST than for periods on OST (N = 7 studies).

Conclusions:

A comprehensive response to injecting drug must include efforts to reduce the high levels of non-AIDS mortality among PWID. Due to limitations of currently available data, including substantial heterogeneity between studies, estimates of non-AIDS mortality specific to geographic regions, country income level, or the availability of OST should be interpreted with caution.

Characteristics of people who initiate injection drug use later in life

BACKGROUND

Studies report that among people who inject drugs (PWID), approximately 1 in 7 initiated injection during their thirties or later (referred to hereafter as "late initiates"). However, little is known about individuals who are late initiates. This study aims to describe characteristics of late initiates to drug injection and to examine how they differ from people who initiated drug injection prior to the age of 30 ("typical initiates").

METHODS

We recruited 696 active PWID in Los Angeles and San Francisco, California between 2011 and 2013, using targeted sampling and street outreach methods. Participants completed personal interviews that covered items on demographics, drug use history and practices, injection initiation episode, HIV injection- and sex-related risk, health care utilization among others. We used bivariate and multivariate analyses to examine factors associated being a late initiate.

RESULTS

In our sample, 19% of participants who were 30 years or older were classified as late initiates. In multivariate analysis controlling for city, late initiates had higher odds of being female and African American, having been in treatment prior to initiation, initiating illicit drug use at an older age, and being assisted into injection by someone of the same age or younger. Late initiates had lower odds of frequent recent injection, and having a bipolar disorder diagnosis.

CONCLUSION

Late initiates comprise a significant proportion of active PWIDs. More study on the health consequences of late initiation are needed as are interventions to prevent transition to drug injection among at-risk populations.

Mortality among people who inject drugs: a systematic review and meta-analysis

OBJECTIVE

To systematically review cohort studies of mortality among people who inject drugs, examine mortality rates and causes of death in this group, and identify participant- and study-level variables associated with a higher risk of death.

METHODS

Tailored search strings were used to search EMBASE, Medline and PsycINFO. The grey literature was identified through online grey literature databases. Experts were consulted to obtain additional studies and data. Random effects meta-analyses were performed to estimate pooled crude mortality rates (CMRs) and standardized mortality ratios (SMRs).

FINDINGS

Sixty-seven cohorts of people who inject drugs were identified, 14 of them from low- and middle-income countries. The pooled CMR was 2.35 deaths per 100 person-years (95% confidence interval, CI: 2.12-2.58). SMRs were reported for 32 cohorts; the pooled SMR was 14.68 (95% CI: 13.01-16.35). Comparison of CMRs and the calculation of CMR ratios revealed mortality to be higher in low- and middle-income country cohorts, males and people who injected drugs that were positive for human immunodeficiency virus (HIV). It was also higher during off-treatment periods. Drug overdose and acquired immunodeficiency syndrome (AIDS) were the primary causes of death across cohorts.

CONCLUSION

Compared with the general population, people who inject drugs have an elevated risk of death, although mortality rates vary across different settings. Any comprehensive approach to improving health outcomes in this group must include efforts to reduce HIV infection as well as other causes of death, particularly drug overdose.

Cost effectiveness of screening strategies for early identification of HIV and HCV infection in injection drug users

OBJECTIVE

To estimate the cost, effectiveness, and cost effectiveness of HIV and HCV screening of injection drug users (IDUs) in opioid replacement therapy (ORT).

DESIGN

Dynamic compartmental model of HIV and HCV in a population of IDUs and non-IDUs for a representative U.S. urban center with 2.5 million adults (age 15-59).

METHODS

We considered strategies of screening individuals in ORT for HIV, HCV, or both infections by antibody or antibody and viral RNA testing. We evaluated one-time and repeat screening at intervals from annually to once every 3 months. We calculated the number of HIV and HCV infections, quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs).

RESULTS

Adding HIV and HCV viral RNA testing to antibody testing averts 14.8-30.3 HIV and 3.7-7.7 HCV infections in a screened population of 26,100 IDUs entering ORT over 20 years, depending on screening frequency. Screening for HIV antibodies every 6 months costs $30,700/QALY gained. Screening for HIV antibodies and viral RNA every 6 months has an ICER of $65,900/QALY gained. Strategies including HCV testing have ICERs exceeding $100,000/QALY gained unless awareness of HCV-infection status results in a substantial reduction in needle-sharing behavior.

DISCUSSION

Although annual screening for antibodies to HIV and HCV is modestly cost effective compared to no screening, more frequent screening for HIV provides additional benefit at less cost. Screening individuals in ORT every 3-6 months for HIV infection using both antibody and viral RNA technologies and initiating ART for acute HIV infection appears cost effective.

HIV infection and risk of overdose: a systematic review and meta-analysis

Drug overdose is a common cause of non-AIDS death among people with HIV and the leading cause of death for people who inject drugs. People with HIV are often exposed to opioid medications during their HIV care experience; others may continue to use illicit opioids despite their disease status. In either situation, there may be a heightened risk for nonfatal or fatal overdose. The potential mechanisms for this elevated risk remain controversial. We systematically reviewed the literature on the HIV-overdose association, meta-analyzed results, and investigated sources of heterogeneity, including study characteristics related to hypothesize biological, behavioral, and structural mechanisms of the association. Forty-six studies were reviewed, 24 of which measured HIV status serologically and provided data quantifying an association. Meta-analysis results showed that HIV seropositivity was associated with an increased risk of overdose mortality (pooled risk ratio 1.74, 95% confidence interval 1.45, 2.09), although the effect was heterogeneous (Q = 80.3, P < 0.01, I(2) = 71%). The wide variability in study designs and aims limited our ability to detect potentially important sources of heterogeneity. Causal mechanisms considered in the literature focused primarily on biological and behavioral factors, although evidence suggests structural or environmental factors may help explain the greater risk of overdose among HIV-infected drug users. Gaps in the literature for future research and prevention efforts as well as recommendations that follow from these findings are discussed.

Excess mortality among HIV-infected patients diagnosed with substance use dependence or abuse receiving care in a fully integrated medical care program

BACKGROUND

We examined the association between substance use (SU) disorder and mortality among HIV-infected patients in a large, private medical care program.

METHODS

In a retrospective cohort design, HIV-infected patients (≥14 years old) from a large health plan (Northern California) were studied to examine mortality associated with diagnosis of SU dependence or abuse over an 11-year period.

RESULTS

At study entry or during follow-up, 2,279 (25%) of 9,178 HIV-infected patients had received a diagnosis of SU disorder. Diagnoses were categorized as alcohol dependence/abuse only, illicit drugs only, or both. Cause of death differed by the category of SU diagnosis. Mortality rates ranged from 35.5 deaths per 1,000 person-years in patients with an SU disorder to 17.5 deaths among patients without an SU disorder. Regression results indicated mortality risk was significantly higher in all categories of SU disorder compared to no SU diagnosis (hazard ratios ranging from 1.65 to 1.67) after adjustment for SU treatment and confounders.

CONCLUSIONS

A diagnosis of SU dependence/abuse is associated with higher mortality among HIV-infected patients for whom access to medical services is not a significant factor.

Increased all-cause and cancer mortality in HTLV-II infection

BACKGROUND

Human T-lymphotropic virus (HTLV)-I and HTLV-II cause chronic human retroviral infections, but few studies have examined the impact of either virus on survival among otherwise healthy individuals. The authors analyzed all-cause and cancer mortality in a prospective cohort of 155 HTLV-I, 387 HTLV-II, and 799 seronegative subjects.

METHODS

Vital status was ascertained using death certificates, the US Social Security Death Index or family report, and causes of death were grouped into 9 categories. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models.

RESULTS

After a median follow-up of 15.9 years, there were 105 deaths: 22 HTLV-I, 41 HTLV-II, and 42 HTLV-seronegative. Cancer was the predominant cause of death, resulting in 8 HTLV-I, 17 HTLV-II, and 15 HTLV-seronegative deaths. After adjustment for confounding, HTLV-I status was not significantly associated with increased all-cause mortality, though there was a positive trend (HR: 1.6, 95% CI: 0.8 to 3.1). HTLV-II status was strongly associated with increased all-cause (HR: 2.4, 95% CI: 1.4 to 4.4) and cancer mortality (HR: 3.8, 95% CI: 1.6 to 9.2).

CONCLUSIONS

The observed associations of HTLV-II with all-cause and cancer mortality could reflect biological effects of HTLV-II infection, residual confounding by socioeconomic status or other factors, or differential access to health care and cancer screening.

Mortality risk among recent-onset injection drug users in five U.S. cities

To quantify the risk of death among recent-onset (< 5 years) injection drug users, we enrolled 2089 injection drug users (IDUs) age <or= 35 years (minimum age = 18 years) between 1997 and 1999. Median age was 24 years, 62.4% were male, 54.5% were non-Hispanic White, mean duration of injecting was 3 years, and 45.4% injected daily within the prior 6 months. Using the National Death Index, we identified 68 deaths over a follow-up period through December 2002 with a mortality rate of 7.10/1000 person years. Using age-, sex-, and race-adjusted data to the census and mortality, we calculated standardized mortality ratios (SMRs) over time. The adjusted SMR (with national data as the reference) for IDUs was 3.66 for 1997, which increased to 9.78 by 1998, decreased slightly to 7.08 by 1999, and continuously declined to 2.54 by 2002. These data confirm considerable excess mortality among recent onset injection drug users compared to non-IDU peers in the general population and indicate need for interventions such as increased quality and accessibility to drug abuse** treatment and overdose prevention to prevent premature death among young IDUs.

In-hospital and long-term mortality in infective endocarditis in injecting drug users compared to non-drug users: a retrospective study of 192 episodes

In a retrospective study, in-hospital and long-term mortality for patients with infective endocarditis (IE) was analysed. The study was conducted at a department of infectious diseases in Stockholm, Sweden. Mortality was compared between injecting drug users (IDUs) and patients without drug abuse (non-IDUs). 192 episodes of IE from 1995 to 2000 were analysed, 60 in IDUs and 135 in non-IDUs, median follow-up 4.4 y. Episodes were classified using the Duke criteria: 145 definite and 47 possible. Of 53 definite episodes in IDUs, 55% were right-sided IE and 43% left-sided IE (including combined left- and right-sided). Surgical treatment was used in 34/145 definite episodes, all being left-sided IE. The in-hospital mortality was 14/145 (9.6%). There was no difference in in-hospital mortality between patient groups with left-sided IE. The IDU patients with left-sided IE had a higher long-term mortality with the increased mortality rate explained by late deaths in the surgically treated IDUs. Treatment results for IDUs with right-sided IE were good with no in-hospital mortality, no relapses and no increase in long-term mortality. This difference in prognosis between left-sided and right-sided IE in IDUs makes high quality echocardiography important to identify patients with left-sided IE and worse prognosis.

[Donor-transmitted infections]

The defence response to infectious agents is compromised in solid organ recipients because of their immunosuppressive treatment. Transmission of infection from a donor organ can result in dysfunction or loss of the allograft, and may lead to death of the recipient if adequate preventive measures are not taken. This potential risk should be thoroughly assessed, particularly in the case of organs from infected donors, in order to optimize organ use without increasing the incidence of graft dysfunction and recipient morbidity and mortality. This article reviews the current knowledge regarding screening for infection in potential donors and discusses risk-benefit considerations related to the use of organs from infected donors.

Factors associated with premature mortality among young injection drug users in Vancouver

BACKGROUND

Young injection drug users (IDUs) may be at increased risk of premature mortality due to the health risks associated with injection drug use including overdoses and infections. However, there has been little research conducted on mortality causes, rates and associations among this population. We undertook this study to investigate patterns of premature mortality, prior to age 30 years, among young IDUs.

METHODS

Since 1996, 572 young (< or = 29 years) IDUs have been enrolled in the Vancouver Injection Drug Users Study (VIDUS). Semi-annually, participants have completed an interviewer-administered questionnaire and have undergone serologic testing for HIV and hepatitis C (HCV). Mortality data have been continually updated through linkages with the Provincial Coroner's Office. Crude and age-specific mortality rates, standardized mortality ratios, and life expectancy measures were calculated using person-time methods. Predictors of mortality were identified using Cox regression analyses.

FINDINGS

Twenty-two participants died prior to age 30 years during the follow-up period for an overall crude mortality rate of 1,368 per 100,000 person-years. Overall, young IDUs were 16.4 times (95% confidence interval [CI]; 9.1-27.1) more likely to die; young women IDUs were 54.1 times (95%CI; 29.6-90.8) and young men IDUs were 12.9 times (95%CI; 5.5, 25.3) more likely to die when compared to the Canadian non-IDU population of the same age. The leading observed cause of death among females was: homicide (N = 9); and among males: suicide (N = 3) and overdose (N = 3). In Cox regression analyses, factors associated with mortality were, HIV infection (Hazard Ratio [HR]: 4.55; CI: 1.92-10.80) and sex work (HR: 2.76; CI: 1.16-6.56).

INTERPRETATION

Premature mortality was 13 and 54 times higher among young men and women who use injection drugs in Vancouver than among the general population in Canada. The majority of deaths among the women were attributable to homicide, suggesting that interventions should occur not only through harm reduction services but also through structural interventions at the legal and policy level.

A comparative study of mortality among Puerto Rican injection drug users in East Harlem, New York, and Bayamon, Puerto Rico

Drug users have been found to be at high risk of mortality but the mortality experience of Hispanic drug users remains understudied. This study assessed mortality among Puerto Rican injection drug users (IDUs) in New York City (NY), and in Puerto Rico (PR). Study subjects were 637 IDUs from NY and 319 IDUs from PR. Mortality was ascertained using data from the National Death Index. Annual mortality rate of the NY cohort was 1.3 per 100 person years compared to the PR cohort with a rate of 4.8. Compared to the Hispanic population of New York City, the standardized mortality ratio (SMR) of the NY cohort was 4.4. Compared to the population of Puerto Rico, the SMR of the PR cohort was 16.2. The four principal causes of death were: NY-HIV/AIDS (50.0%), drug overdoses (13.3%), cardiovascular conditions (13.3%), and pulmonary conditions (10.0%); PR-HIV/AIDS (37.0%), drug overdoses (24.1%), sepsis (13.0%), and homicide (11.1%). Modeling time to death using Cox proportional hazards regression, the relative risk of mortality of the PR cohort as compared to the NY cohort was 9.2. The other covariates found to be significantly associated with time to death were age, gender, education, social isolation, intoxication with alcohol, and HIV seropositivity. The large disparity in mortality rates found in this study suggests that health disparities research should be expanded to identify intra-group disparities. Furthermore, these results point to an urgent need to reduce excess mortality among IDUs in Puerto Rico.

Using cohort studies to estimate mortality among injecting drug users that is not attributable to AIDS

BACKGROUND

Injecting drug use (IDU) and associated mortality appear to be increasing in many parts of the world. IDU is an important factor in HIV transmission. In estimating AIDS mortality attributable to IDU, it is important to take account of premature mortality rates from other causes to ensure that AIDS related mortality among injecting drug users (IDUs) is not overestimated. The current review provides estimates of the excess non-AIDS mortality among IDUs.

METHOD

Searches were conducted with Medline, PsycINFO, and the Web of Science. The authors also searched reference lists of identified papers and an earlier literature review by English et al (1995). Crude mortality rates (CMRs) were derived from data on the number of deaths, period of follow up, and number of participants. In estimating the all-cause mortality, two rates were calculated: one that included all cohort studies identified in the search, and one that only included studies that reported on AIDS deaths in their cohort. This provided lower and upper mortality rates, respectively.

RESULTS

The current paper derived weighted mortality rates based upon cohort studies that included 179 885 participants, 1,219,422 person-years of observation, and 16,593 deaths. The weighted crude AIDS mortality rate from studies that reported AIDS deaths was approximately 0.78% per annum. The median estimated non-AIDS mortality rate was 1.08% per annum.

CONCLUSIONS

Illicit drug users have a greatly increased risk of premature death and mortality due to AIDS forms a significant part of that increased risk; it is, however, only part of that risk. Future work needs to examine mortality rates among IDUs in developing countries, and collect data on the relation between HIV and increased mortality due to all causes among this group.

Co-Infection by the Human T-Cell Lymphotropic Virus Type II in Patients Infected by the Human Immunodeficiency Virus in Yucatan, Mexico

BACKGROUND

The HTLV-II infection has been reported in patients with HIV infection as often in asymptomatic as those with acquired immunodeficiency syndrome (AIDS). The aim of this study was to determine the prevalence of HTLV-II infection in a group of patients infected by HIV in our region, as well as determining the risk factors associated with HTLV-II transmission in this group of patients and its impact on the clinical course of HIV infection.

METHODS

A cross-sectional study was carried out to determine the prevalence of co-infection of HIV-1 and HTLV-II among 192 patients from Yucatán, México. Serum specimens were tested for HTLV antibodies by an enzyme-linked immunosorbent assay (ELISA) test. Positive results were confirmed and typed by Western blot. Twenty four (12.5%) patients were confirmed with antibodies for HTLV-II, but none had antibodies for HTLV-I. Specific risk factors for HTLV-II transmission were not identified.

RESULTS

Candidiasis (42 vs. 12%, p = 0.0004) and more than two defining entities of AIDS (37 vs. 18%, p = 0.02) was observed with greater prevalence in the group co-infected.

CONCLUSIONS

In our study, a higher frequency of candidiasis and a larger number of AIDS-defining pathologies were observed in the co-infected patients, suggesting that co-infection is associated with greater immunodeficiency.

Hepatitis C virus load and survival among injection drug users in the United States

Persons chronically infected with hepatitis C virus (HCV), some of whom may be coinfected with HIV and human T-lymphotropic virus type II (HTLV-II), are at high risk for end-stage liver disease (ESLD). We evaluated whether ESLD death was associated with premorbid HCV RNA level or specific HCV protein antibodies among persons with or without HIV/HTLV-II coinfection in a cohort of 6,570 injection drug users who enrolled in 9 US cities between 1987 and 1991. We compared 84 ESLD descendents and 305 randomly selected cohort participants with detectable HCV RNA, stratified by sex, race, HIV, and HTLV-II strata. Relative hazard (RH) of ESLD death was derived from the proportional hazard model. Risk of ESLD death was unrelated to the intensity of antibodies against the HCV c-22(p), c-33(p), c-100(p), and NS5 proteins, individually or combined, but it increased with HCV RNA level (RH(adj) = 2.26 per log(10) IU/mL, 95% CI: 1.45-5.92). The association between HCV RNA level and ESLD death remained significant after adjustment for alcohol consumption (RH(adj) = 2.57 per log(10) IU/mL, 95% CI: 1.50-8.10). Deaths from AIDS (n = 45) and other causes (n = 43) were unrelated to HCV RNA (RH(adj)= 1.14 and 1.29 per log(10) IU/mL, respectively). HIV infection was not associated with ESLD risk in multivariate analyses adjusted for HCV RNA. Men had an increased risk of ESLD death in unadjusted analyses (RH = 1.92, 95% CI: 1.15-3.56) but not in multivariate analysis (RH(adj) = 0.98, 95% CI: 0.48-2.88). Non-black patients were at increased risk for ESLD death (RH(adj)= 2.76, 95% CI: 1.49-10.09). In conclusion, HCV RNA level is a predictor of ESLD death among persons with chronic HCV infection.

Potential cost-effectiveness of a preventive hepatitis C vaccine in high risk and average risk populations in Canada

Hepatitis C virus (HCV) vaccine development remains at an early stage. We explored the economic and health consequences of potential HCV vaccines by comparing universal vaccination with a hepatitis C vaccine to no vaccination in two groups: (1) injecting drug users (IDU); (2) all 12 year olds, using a Markov cohort simulation. Among IDUs, vaccination would avert 248 cases of HCV infection and 89 HCV-related deaths per 1000 individuals, and reduce costs. In average risk cohorts, vaccination did not reduce costs but was reasonably cost effective. These results provide encouragement to vaccine developers that a vaccine that is moderately effective and reasonably priced should not face economic barriers to implementation and will be attractive to third party payers.

Mortality risk among new onset injection drug users

AIMS

To characterize mortality experience among those who only recently started injection.

DESIGN

Prospective study.

SETTING

Independent study clinic within high drug use neighborhoods.

PARTICIPANTS

In 1988-1989, we enrolled 256 adult injection drug users (IDUs) recruited through street outreach who had initiated injection within the prior 2 years.

MEASUREMENTS

Consenting participants underwent venipuncture for HIV antibody testing and interviews. We prospectively ascertained date and cause of death through follow-up contact and registry linkages. Analyses included standardized mortality ratios (SMRs) with local, state and national mortality data, adjusted for age, gender and race.

FINDINGS

Baseline median age was 30 years, 70% were male, 95% were African-American and 90% injected within the prior 6 months. We identified 69 deaths through October 2000; mortality rate was 3.3/100 person-years. The adjusted SMR with the USA (and Baltimore) as the reference for IDUs was 4.40 (2.43) for 1991-1992, which increased to 8.12 (4.13) by 1993-1994, decreased to 4.43 (2.13) by 1997-1998 and increased slightly to 5.35 (2.79) during 1999-2000. Excluding HIV-related mortality, SMRs remained elevated. Decline in SMRs was not linked to drug abuse treatment.

CONCLUSIONS

These data demonstrate excess mortality among new-onset IDUs compared with demographically similar peers in the general population, indicating the need for interventions to prevent premature death among young IDUs.

Clinical Outcomes and Disease Progression among Patients Coinfected with HIV and Human T Lymphotropic Virus Types 1 and 2

The goal of this study was to investigate clinical outcomes and survival probabilities among persons coinfected with human immunodeficiency virus (HIV) and human T lymphotropic viruses types 1 and 2 (HTLV-I/II). A nonconcurrent cohort study of 1033 HIV-infected individuals was also conducted. Sixty-two patients were coinfected with HTLV-I, and 141 patients were coinfected with HTLV-II. HTLV-I/II coinfection was highly associated with African-American race/ethnicity, age of >36 years, higher CD4(+) T cell count at baseline and over time, and history of injection drug use. Coinfected patients were more likely to have neurologic complications, thrombocytopenia, respiratory and urinary tract infections, and hepatitis C. Despite having higher CD4(+) T cell counts over time, there was no difference in the incidence of opportunistic infections. Progression to both acquired immunodeficiency syndrome (AIDS; adjusted hazard ratio [aHR], 0.50; 95% confidence interval [CI], 0.25-0.98) and death (aHR, 0.57, 95% CI, 0.37-0.89) were slower among HTLV-II-coinfected patients, compared with time-entry- and CD4(+) T cell count-matched control subjects. In conclusion, HIV-HTLV-I/II coinfection may result in improved survival and delayed progression to AIDS, but this happens at the expense of an increased frequency of other of clinical complications.

Developing a directly administered antiretroviral therapy intervention for HIV-infected drug users: implications for program replication

Directly administered antiretroviral therapy (DAART) is one approach to improving adherence to among human immunodeficiency virus (HIV)-infected drug users. We evaluated the essential features of a community-based DAART intervention in a randomized, controlled trial of DAART versus self-administered therapy. Of the initial 72 subjects, 78% were racial minorities, and 32% were women. Social and medical comorbidities among subjects included homelessness (35% of subjects), lack of interpersonal support (86%), major depression (57%), and alcoholism (36%). At baseline, the median CD4+ cell count was 403 cells/mL and the median HIV-1 RNA load was 146,333 copies/mL (log10 5.31 copies/mL). During the prior 6 months, 33% of subjects had missed a medical appointment, and 47% had visited an emergency department. Although most subjects (67%) preferred to take their own medications, 76% would accept DAART if it were made compulsory. A methadone clinic was the DAART venue acceptable to the fewest subjects (36%), and a mobile syringe-exchange program was acceptable to the most subjects (83%). Adherence was higher for supervised than for unsupervised medication administration (P<.0001), a finding that supports use of daily supervision of once-daily regimens. Moreover, DAART should incorporate enhanced elements such as convenience, flexibility, confidentiality, cues and reminders, responsive pharmacy and medical services, and specialized training for staff.

Increased mortality associated with HTLV-II infection in blood donors: a prospective cohort study

Background

HTLV-I is associated with adult T-cell leukemia, and both HTLV-I and -II are associated with HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Several published reports suggest that HTLV-I may lead to decreased survival, but HTLV-II has not previously been associated with mortality.

Results

We examined deaths among 138 HTLV-I, 358 HTLV-II, and 759 uninfected controls enrolled in a prospective cohort study of U.S. blood donors followed biannually since 1992. Proportional hazards models yielded hazard ratios (HRs) for the association between mortality and HTLV infection, controlling for sex, race/ethnicity, age, income, educational level, blood center, smoking, injection drug use history, alcohol intake, hepatitis C status and autologous donation. After a median follow-up of 8.6 years, there were 45 confirmed subject deaths. HTLV-I infection did not convey a statistically significant excess risk of mortality (unadjusted HR 1.9, 95%CI 0.8–4.4; adjusted HR 1.9, 95%CI 0.8–4.6). HTLV-II was associated with death in both the unadjusted model (HR 2.8, 95%CI 1.5–5.5) and in the adjusted model (HR 2.3, 95%CI 1.1–4.9). No single cause of death appeared responsible for the HTLV-II effect.

Conclusions

After adjusting for known and potential confounders, HTLV-II infection is associated with increased mortality among healthy blood donors. If replicated in other cohorts, this finding has implications for both HTLV pathogenesis and counseling of infected persons.

Impact of donor infections on outcome of orthotopic liver transplantation

Infection occurs when microbial agents enter the host, either through airborne transmission or by direct contact of a substance carrying the infectious agent with the host. Human body fluids, solid organs, or other tissues often are ideal vectors to support microbial agents and can transmit infections efficiently from donor to recipient. In the case of blood transfusion and tissue transplantation, the main consequence of such a transmission is infection of the recipient. However, in the case of solid-organ transplantation, and particularly for liver transplantation, donor infections are not only transmitted to the recipient, the donor infection also may affect the donated liver's preservability and subsequent function in the recipient irrespective of the systemic consequences of the infection. In addition, solid organ recipients of infected organs are less able to respond to the infectious agent because of their immunosuppressive treatment. Thus, transmission of infections from organ donor to liver recipient represents serious potential risks that must be weighed against a candidate's mortality risk without the transplant. However, the ever-increasing gap between the number of donors and those waiting for liver grafts makes consideration of every potential donor, regardless of the infection status, essential to minimize waiting list mortality. In this review, we will focus on assessing the risk of transmission of bacterial, fungal, viral, and parasitic infectious agents from cadaveric liver donors to recipients and the effect such a transmission has on liver function, morbidity, and mortality. We will also discuss risk-benefit deliberations for using organs from infected donors for certain types of recipients. These issues are critically important to maximize the use of donated organs but also minimize recipient morbidity and graft dysfunction.

HIV-1 infection in injection drug users

Injection drug use is an efficient and ongoing means of HIV transmission and is the principal mode of transmission in some parts of the world. In the United States, approximately 10,000 injection drug users are believed to acquire HIV each year. The US Public Health Service hopes to decrease all HIV transmission in the United States by 50% in the next 5 years, by promoting care and prevention services to infected persons. Subtle differences in the virology and immunopathogenesis of HIV between injection drug users and other groups at risk are still being investigated. So far such differences have no practical implication. Comparison of progression rates and survival with HIV across risk groups has been difficult because of the many competing causes of death unrelated to HIV among injection drug users, but overall HIV disease progression rates are similar across risk groups, after adjusting for age. Some AIDS-related opportunistic infections are more common (such as tuberculosis) or less common (such as Kaposi's sarcoma) among injection drug users, based on rates of exposure and latent infection. Other comorbidities, including chronic psychiatric disorders and hepatitis C disease, are more common among injection drug users than among others with HIV infection. Highly active antiretroviral treatment seems to be as effective in persons with a history of injected drug use as in others. Increasing the numbers of HIV-infected injection drug users who know their diagnosis, increasing their access to care and prevention services, and increasing their adherence to a therapeutic regimen are the current challenges in confronting the HIV-epidemic among injection drug users. To overcome these obstacles, clinicians must have both technical knowledge and skill in assisting patients with behavior change.

Human T-cell lymphotrophic virus infection in organ donors: a need to reassess policy?

Human T-cell lymphotrophic virus (HTLV)-I/II infection has been considered a contra-indication to organ donation due to the risk of transmission of infection and the subsequent development of either adult T-cell leukemia or HTLV-I-associated myelopathy. However, neither the incidence of HTLV-I/II infection in organ donors nor the risk of transmission of HTLV-I/II by solid organ transplantation has been defined. Further, it is not known if HTLV infection contributes to significant morbidity in solid organ recipients. The purpose of this study was to evaluate the incidence of HTLV-I/II infection in organ donors in USA and to determine if transplanting these organs resulted in HTLV-related morbidity or mortality. We utilized the UNOS database to: (i) identify organ donors that were positive for HTLV-I or II infection between 1988 and 2000, and (ii) evaluate outcomes in the recipients of these organs. There were 25 HTLV-I/II-positive organ donors reported to UNOS between 1988 and 2000. Based on organ donors with a known HTLV-I/II status, the prevalence of HTLV-I infection in organ donors is 0.027% and the prevalence of HTLV-II is 0.064%. Twenty-two organs were transplanted from these HTLV-positive donors. There have been no reports of HTLV-I/II-related disease in the recipients with a median follow-up of 11.9 months. At our center, over the last 1.5 years there have been four multiorgan donors with false-positive HTLV-I/II screening assays, which resulted in the decision not to use organs from these donors. Based on the minimal chance of HTLV-related disease following transplantation of HTLV-I/II organs in this series, we recommend that careful consideration be given to transplanting organs from HTLV-I/II-positive organ donors.

Chimeric synthetic peptides from the envelope (gp46) and the transmembrane (gp21) glycoproteins for the detection of antibodies to human T-cell leukemia virus type II

Two chimeric synthetic peptides incorporating immunodominant sequences from HTLV-II virus were synthesized. Monomeric peptides P2 and P3 represent sequences from transmembrane protein (gp21) and envelope protein (gp46) of the virus. The peptide P2 is a gp21 (370-396) sequence and the peptide P3 is a gp46 (178-205) sequence. Those peptides were arranged in a way that permits one to obtain different combinations of chimeric peptides (P2-GG-P3 and P3-GG-P2), separated by two glycine residues as spacer arms. The antigenic activity of these peptides was evaluated by UltramicroEnzyme-linked immunosorbent assay (UMELISA) by using panels anti-HTLV-II-positive sera (n = 11), anti-HTLV-I/II-positive sera (n = 2), HTLV-positive (untypeable) serum samples (n = 2), and anti-HTLV-I-positive sera (n = 22), while specificity was evaluated with anti-HIV-positive samples (n = 19) and samples from healthy blood donors (n = 30). The efficacy of the chimeric peptides in solid-phase immunoassays was compared with the monomeric peptides and a mixture of the monomeric peptides. Higher sensitivity was observed for chimeric peptide Q5 assay. Those results may be related to a higher peptide adsorption capacity to the solid surface and for epitope accessibility to the antibodies. This chimeric peptide would be very useful for HTLV-II diagnostic.