Outcomes of antiretroviral therapy in the Swiss HIV Cohort Study: latent class analysis

An in-depth understanding of the different groups that make up the HIV-infected population should inform prevention and care. Using latent class analysis (LCA) we identified seven groups with similar socio-demographic and behavioral characteristics at enrolment in the Swiss HIV Cohort Study: older gay men, younger gay men, older heterosexual men, injection drug users, single migrants, migrant women in partnerships and heterosexual men and women. Outcomes of combination antiretroviral therapy (ART) were analyzed in 1,633 patients starting ART. Compared to older gay men, the probability of a virologic response to ART was reduced in single migrants, in older heterosexual men and in IDUs. Loss to follow-up was higher in single migrants and IDUs, and mortality was increased in older heterosexual men and IDUs. Socio-behavioral groups identified by LCA allow insights above what can be gleaned from traditional transmission groups, and may identify patients who could benefit from targeted interventions.

Prevention of mother-to-child transmission of human immunodeficiency virus among pregnant women using injecting drugs in Ukraine, 2000-10

AIMS

To compare clinical status, mother-to-child transmission (MTCT) rates, use of prevention of (PMTCT) interventions and pregnancy outcomes between HIV-infected injecting drug users (IDUs) and non-IDUs.

DESIGN AND SETTING

Prospective cohort study conducted in seven human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) Centres in Ukraine, 2000-10.

PARTICIPANTS

Pregnant HIV-infected women, identified before/during pregnancy or intrapartum, and their live-born infants (n = 6200); 1028 women followed post-partum.

MEASUREMENTS

Maternal and delivery characteristics, PMTCT prophylaxis, MTCT rates, preterm delivery (PTD) and low birth weight (LBW).

FINDINGS

Of 6200 women, 1111 (18%) reported current/previous IDU. The proportion of IDUs diagnosed with HIV before conception increased from 31% in 2000/01 to 60% in 2008/09 (P < 0.01). Among women with undiagnosed HIV at conception, 20% of IDUs were diagnosed intrapartum versus 4% of non-IDUs (P < 0.01). At enrolment, 14% of IDUs had severe/advanced HIV symptoms versus 6% of non-IDUs (P < 0.001). IDUs had higher rates of PTD and LBW infants than non-IDUs, respectively, 16% versus 7% and 22% versus 10% (P < 0.001). IDUs were more likely to receive no neonatal or intrapartum PMTCT prophylaxis compared with non-IDUs (OR 2.81, p < 0.001). MTCT rates were 10.8% in IDUs versus 5.9% in non-IDUs; IDUs had increased MTCT risk (adjusted odds ratio 1.32, P = 0.049). Fewer IDUs with treatment indications received HAART compared with non-IDUs (58% versus 68%, P = 0.03).

CONCLUSIONS

Pregnant human immunodeficiency virus-infected injecting drug users in Ukraine have worse clinical status, poorer access to prevention of mother-to-child transmission prophylaxis and highly active antiretroviral therapy, more adverse pregnancy outcomes and higher risk of mother-to-child transmission than non-injecting drug user women.

Estimating loss to follow-up in HIV-infected patients on antiretroviral therapy: the effect of the competing risk of death in Zambia and Switzerland

BACKGROUND

Loss to follow-up (LTFU) is common in antiretroviral therapy (ART) programmes. Mortality is a competing risk (CR) for LTFU; however, it is often overlooked in cohort analyses. We examined how the CR of death affected LTFU estimates in Zambia and Switzerland.

METHODS AND FINDINGS

HIV-infected patients aged ≥18 years who started ART 2004-2008 in observational cohorts in Zambia and Switzerland were included. We compared standard Kaplan-Meier curves with CR cumulative incidence. We calculated hazard ratios for LTFU across CD4 cell count strata using cause-specific Cox models, or Fine and Gray subdistribution models, adjusting for age, gender, body mass index and clinical stage. 89,339 patients from Zambia and 1,860 patients from Switzerland were included. 12,237 patients (13.7%) in Zambia and 129 patients (6.9%) in Switzerland were LTFU and 8,498 (9.5%) and 29 patients (1.6%), respectively, died. In Zambia, the probability of LTFU was overestimated in Kaplan-Meier curves: estimates at 3.5 years were 29.3% for patients starting ART with CD4 cells <100 cells/µl and 15.4% among patients starting with ≥ 350 cells/µL. The estimates from CR cumulative incidence were 22.9% and 13.6%, respectively. Little difference was found between naïve and CR analyses in Switzerland since only few patients died. The results from Cox and Fine and Gray models were similar: in Zambia the risk of loss to follow-up and death increased with decreasing CD4 counts at the start of ART, whereas in Switzerland there was a trend in the opposite direction, with patients with higher CD4 cell counts more likely to be lost to follow-up.

CONCLUSIONS

In ART programmes in low-income settings the competing risk of death can substantially bias standard analyses of LTFU. The CD4 cell count and other prognostic factors may be differentially associated with LTFU in low-income and high-income settings.

Efficacy, adherence and tolerability of once daily tenofovir DF-containing antiretroviral therapy in former injecting drug users with HIV-1 receiving opiate treatment: results of a 48-week open-label study

OBJECTIVE

To assess efficacy, adherence and tolerability of once daily antiretroviral therapy containing tenofovir disoproxil fumarate (DF) 300 mg in HIV-1-infected former injecting drug users receiving opiate treatment (IVDU).

METHODS

European, 48-week, open-label, single-arm, multicenter study. Patients were either antiretroviral therapy-naive, restarting therapy after treatment discontinuation without prior virological failure or switching from existing stable treatment.

RESULTS

Sixty-seven patients were enrolled in the study and 41 patients completed treatment. In the primary analysis (intent-to-treat missing=failure) at week 48, 34% of patients (23/67; 95% CI: 23%-47%) had plasma HIV-1 RNA <50 copies/mL. Using an intent-to-treat missing=excluded approach, the week 48 proportion of patients with plasma HIV-1 RNA <50 copies/mL increased to 56% (23/41; 95% CI: 40%-72%). Mean (standard deviation) increase from baseline in CD4+ cell count at week 48 was 176 (242) cells/mm(3). Although self-reported adherence appeared high, there were high levels of missing data and adherence results should be treated with caution. No new safety issues were identified.

CONCLUSIONS

Levels of missing data were high in this difficult-to-treat population, but potent antiretroviral suppression was achieved in a substantial proportion of HIV-infected IVDU-patients.

Adherence and plasma HIV RNA response to antiretroviral therapy among HIV-seropositive injection drug users in a Canadian setting

HIV-positive individuals who use injection drugs (IDU) may have lower rates of adherence to highly active antiretroviral therapy (ART). However, previous studies of factors associated with adherence to ART among IDU have been limited primarily to samples drawn from clinical settings and in areas with financial barriers to healthcare.We evaluated patterns of ART adherence and rates of plasma HIV RNA response among a Canadian cohort of community-recruited IDU. Using data from a community-recruited cohort of antiretroviral-naive HIV-infected IDU, we investigated ART adherence patterns based on prescription refill compliance and factors associated with time to plasma HIV-1 RNA suppression (<500 copies/mL) using Cox proportional hazards regression in a setting with universal health care, including free ART. Between 1996 and 2008, 267 antiretroviral-naive HIV-infected IDU initiated ART and had a median of 51 months (inter-quartile range: 17-95 months) of follow-up. Overall, 81 (30.3%) were ≥95% adherent during the first year of HAART and 187 (70.0%) achieved HIV RNA suppression at least once over the study period, for an incidence-density of 34.5 (95% confidence interval [CI]: 29.8-39.9) per 100 person-years. The Kaplan-Meier cumulative plasma HIV RNA suppression rates at 12 months after the initiation of ART were 80.8% (95% CI: 71.2-88.7) for adherent and 28.9% (95% CI: 22.8-36.1) for non-adherent participants. While several socio-demographic characteristics and drug-using behaviours were identified as barriers to successful treatment in unadjusted analyses, the factor most strongly associated with time to HIV RNA suppression in multivariate analysis was adherence to ART of at least 95% (adjusted hazard ratio [AHR] = 6.0, 95% CI: 4.2-8.6, p<0.001). These results demonstrate low rates of adherence to ART among a community-recruited cohort of IDU and reinforce the importance of adherence as the key determinant of successful virological response to antiretroviral therapy.

Long-term immunological outcomes in treated HIV-infected individuals in high-income and low-middle income countries

PURPOSE OF REVIEW

To summarize the recent findings on long-term (at least 3-4 years) immunological responses to combination antiretroviral therapy (cART) and to compare and contrast the findings between cohorts from high-income and low-middle income countries (LMICs).

RECENT FINDINGS

Cohort studies from high-income settings suggest that a majority of treated HIV-infected patients who maintain suppressed HIV viremia experience a gradual increase in CD4 cell counts for several years to normal levels. However, those who start cART at CD4 cell counts less than 200 cells/μl (as opposed to CD4 cell counts>200 cells/μl) spend several more years below the safe CD4 cell count threshold of 500 cells/μl. Cohorts from LMICs also report persistent improvements in CD4+ cell counts over first 4-5 years of follow-up. However, low-CD4 cell counts (<200 cells/μl) at the start of cART, high early mortality, and loss to follow-up in LMICs settings suggest that the observed optimistic responses may be affected by survivorship bias and should be cautiously interpreted as the optimal, rather than an average, response in LMICs populations.

SUMMARY

LMICs cohorts report similar immunological responses to cART as high-income countries in first 4-5 years of follow-up. Sustaining success in these settings is dependent on timely access to first-line and future cART options, efforts to reduce loss to follow-up, and implementation of treatment guidelines. Cohorts from LMICs are encouraged to continue improving treatment programs and to continue reporting outcomes over the next decade, as surveillance for potential future blunting in responses.

The effect of injecting drug use history on disease progression and death among HIV-positive individuals initiating combination antiretroviral therapy: collaborative cohort analysis

BACKGROUND

We examined whether determinants of disease progression and causes of death differ between injecting drug users (IDUs) and non-IDUs who initiate combination antiretroviral therapy (cART).

METHODS

The ART Cohort Collaboration combines data from participating cohort studies on cART-naïve adults from cART initiation. We used Cox models to estimate hazard ratios for death and AIDS among IDUs and non-IDUs. The cumulative incidence of specific causes of death was calculated and compared using methods that allow for competing risks.

RESULTS

Data on 6269 IDUs and 37 774 non-IDUs were analysed. Compared with non-IDUs, a lower proportion of IDUs initiated cART with a CD4 cell count <200 cells/μL or had a prior diagnosis of AIDS. Mortality rates were higher in IDUs than in non-IDUs (2.08 vs. 1.04 per 100 person-years, respectively; P<0.001). Lower baseline CD4 cell count, higher baseline HIV viral load, clinical AIDS at baseline, and later year of cART initiation were associated with disease progression in both groups. However, the inverse association of baseline CD4 cell count with AIDS and death appeared stronger in non-IDUs than in IDUs. The risk of death from each specific cause was higher in IDUs than non-IDUs, with particularly marked increases in risk for liver-related deaths, and those from violence and non-AIDS infection.

CONCLUSION

While liver-related deaths and deaths from direct effects of substance abuse appear to explain much of the excess mortality in IDUs, they are at increased risk for many other causes of death, which may relate to suboptimal management of HIV disease in these individuals.

Attitudes toward opioid substitution therapy and pre-incarceration HIV transmission behaviors among HIV-infected prisoners in Malaysia: implications for secondary prevention

BACKGROUND

Pre-incarceration HIV transmission behaviors and current attitudes toward opioid substitution therapy (OST) among HIV-infected male prisoners in Malaysia have important implications for secondary HIV prevention efforts.

METHODS

In June 2007, 102 HIV-infected male prisoners within 6 months of community-release were anonymously surveyed in Kota Bharu, Malaysia.

RESULTS

Nearly all subjects (95%) met criteria for opioid dependence. Overall, 66% of participants reported sharing needles, and 37% reported unprotected sex in the 30 days prior to incarceration. During this period, 77% reported injection drug use, with 71% injecting daily and 65% injecting more than one substance. Injection of buprenorphine (28%), benzodiazepines (28%) and methamphetamines (49%) was reported. Nearly all (97%) of those reporting unprotected sex did so with someone not known to be HIV-infected. While 51% believed that opioid substitution therapy (OST) would be helpful, only 33% believed they needed it to prevent relapse after prison release. Most participants (70%) expressed interest in learning more about OST. Those reporting the highest injection risks were more likely to believe OST would be helpful (p<0.05), to believe that it was needed to prevent relapse post-release (p<0.05), and to express interest in learning more about OST (p<0.01).

CONCLUSIONS

Secondary HIV prevention among prisoners in Malaysia is crucial to reduce community HIV transmission after release. Effectively reducing HIV risk associated with opioid injection will require OST expansion, including social marketing to improve its acceptability and careful monitoring. Access to sterile injection equipment, particularly for non-opioid injectors, and behavioral interventions that reduce sexual risk will also be required.

Association of ongoing drug and alcohol use with non-adherence to antiretroviral therapy and higher risk of AIDS and death: results from ACTG 362

Drug and alcohol use have been associated with a worse prognosis in short-term and cross-sectional analyses of HIV-infected populations, but longitudinal effects on adherence to antiretroviral therapy (ART) and clinical outcomes in advanced AIDS are less well characterized. We assessed self-reported drug and alcohol use in AIDS patients, and examined their association with non-adherence and death or disease progression in a multicenter observational study. We defined non-adherence as reporting missed ART doses in the 48 hours before study visits. The association between drug use and ART non-adherence was evaluated using repeated measures generalized estimating equation (GEE) models. The association between drug and alcohol use and time to new AIDS diagnosis or death was evaluated via Cox regression models, controlling for covariates including ART adherence. Of 643 participants enrolled between 1997 and 1999 and followed through 2007, at entry 39% reported ever using cocaine, 24% amphetamines, and 10% heroin. Ongoing drug use during study follow-up was reported by 9% using cocaine, 4% amphetamines, and 1% heroin. Hard drug (cocaine, amphetamines, or heroin) users had 2.1 times higher odds (p=0.001) of ART non-adherence in GEE models and 2.5 times higher risk (p=0.04) of AIDS progression or death in Cox models. Use of hard drugs was attenuated as a risk factor for AIDS progression or death after controlling for non-adherence during follow-up (HR = 2.11, p=0.08), but was still suggestive of a possible adherence-independent mechanism of harm. This study highlights the need to continuously screen and treat patients for drug use as a part of ongoing HIV care.

Ongoing drug use and outcomes from highly active antiretroviral therapy among injection drug users in a Canadian setting

BACKGROUND

The effect of ongoing illicit drug use on HIV treatment remains controversial, especially in countries where access to HIV treatment for active injection drug users (IDUs) is limited because of presumed non-adherence. We sought to investigate the influence of drug use patterns on adherence to antiretroviral therapy and virological suppression among IDUs.

METHODS

Using generalized estimating equation logistic regression, we explored the effect of abstinence versus ongoing drug use on adherence and virological suppression using data from a community-recruited cohort of IDUs in Vancouver (BC, Canada).

RESULTS

A total of 381 HIV-positive IDUs were included in this analysis, among whom the median follow-up time was 30 months. In a multivariate model, no relationship was found between abstinence (reference) and active injection (adjusted odds ratio [AOR] 0.88, 95% confidence interval [CI] 0.65-1.17) and non-injection (AOR 0.97, 95% CI 0.67-1.41) drug use with adherence. In subanalyses, ongoing injection drug use was associated with a lower odds of virological suppression in comparison to abstinence (AOR 0.74, 95% CI 0.57-0.97; P=0.026) and both active IDUs and active non-IDUs had lower odds of virological suppression compared with abstinent participants when longer periods of virological suppression were considered.

CONCLUSIONS

Given the absence of a strong relationship between abstinence and ongoing drug use and adherence among HIV-positive IDUs, programmes that restrict antiretrovirals to abstinent individuals should be re-examined. The lower rates of virological suppression associated with ongoing drug use nevertheless highlight the importance of comprehensive systems of care and addiction treatment for active drug users.

Impact of injecting drug use on response to highly active antiretroviral treatment in HIV-1-infected patients: a nationwide population-based cohort study

The objective of this study was to determine the effect of highly active antiretroviral therapy (HAART) in human immunodeficiency virus (HIV)-infected patients infected through injecting drug use (injecting drug users, IDUs) compared to patients infected via other routes (non-IDUs). We conducted a nationwide population-based cohort study of all HIV-infected patients who initiated HAART during the study period of 1 January 1995 to 31 December 2007. We compared changes in CD4(+) cell counts, percentage of full viral suppression (< 500 copies/ml) and mortality from start of HAART, as well as differences in initial HAART regimen. Three thousand six hundred and fifteen patients were included in the study, representing 22,804 person-y of observation. A total of 346 (9.6%) were categorized as IDUs. Of IDUs, 55% gained full viral control within the first y after HAART compared to 76% of non-IDUs (p = 0.0002). Absolute CD4(+) cell count and survival were lower for IDUs compared to non-IDUs (adjusted mortality rate ratio 3.6 (95% CI 2.9-4.3)). IDUs were more likely to receive a first regimen based on protease inhibitors (PIs) compared to non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens for non-IDUs, and IDUs initiated HAART later than non-IDUs. In conclusion, more than half of the HIV-infected patients in Denmark infected through injecting drug use gained full viral suppression after initiating HAART. Absolute CD4(+) cell count was lower and mortality higher among IDUs than non-IDUs.

Treatment and care for injecting drug users with HIV infection: a review of barriers and ways forward

We review evidence for effectiveness, cost-effectiveness, and coverage of antiretroviral therapy (ART) for injecting drug users (IDUs) infected with HIV, with particular attention to low-income and middle-income countries. In these countries, nearly half (47%) of all IDUs infected with HIV are in five nations--China, Vietnam, Russia, Ukraine, and Malaysia. In all five countries, IDU access to ART is disproportionately low, and systemic and structural obstacles restrict treatment access. IDUs are 67% of cumulative HIV cases in these countries, but only 25% of those receiving ART. Integration of ART with opioid substitution and tuberculosis treatment, increased peer engagement in treatment delivery, and reform of harmful policies--including police use of drug-user registries, detention of drug users in centres offering no evidence-based treatment, and imprisonment for possession of drugs for personal use--are needed to improve ART coverage of IDUs.

Human immunodeficiency virus-associated neurocognitive disorder: pathophysiology in relation to drug addiction

Human immunodeficiency virus (HIV) infection in the United States and increasingly in other parts of the world is now being driven by drug-abusing populations. Both HIV infection and drugs of abuse affect the basal ganglia, hippocampal structures, and the prefrontal cortex. Understanding the interactions between the two and their combined effects is critical. In vitro studies show that opiates, methamphetamine, and cocaine can potentiate HIV replication and can enhance or synergize with HIV proteins to cause glial cell activation, neurotoxicity, and breakdown of the blood-brain barrier. Many of these studies have been confirmed in vivo by using rodent models. However, the complexities of polydrug addiction and drug withdrawal have yet to be examined in simian models of HIV-associated neurocognitive disorder. Clinical studies in substance-abusing, HIV-positive patients pose multiple challenges whether aimed at studying disease pathogenesis or conducting clinical trials. This review examines the literature to date, lists the experimental challenges faced by researchers studying effects of drug addiction on HIV neuropathogenesis, and suggests future directions for research.