Stavudine, lamivudine and indinavir in drug abusing and non-drug abusing HIV-infected patients: adherence, side effects and efficacy

What do HIV-positive drug users' experiences tell us about their antiretroviral medication-taking? An international integrated literature review

BACKGROUND AND AIMS

HIV-positive drug users' poor adherence to antiretroviral regimens can pose a significant and negative impact on individual and global health. This review aims to identify knowledge gaps and inconsistencies within the current evidence base and to measure HIV-positive drug users' adherence rates and the factors that influence their adherence.

METHODS

A search of quantitative and qualitative studies in relation to HIV-positive drug users' adherence to antiretroviral treatment was performed using five databases: Applied Social Sciences Index and Abstract (ASSIA), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Medline, Embase and PsycINFO (Ovid interface). Relevant studies were retrieved based on the inclusion and exclusion criteria stated in the review. Findings were compared, contrasted and synthesized to provide a coherent account of HIV-positive drug users' adherence rates and the factors that influence their adherence.

RESULTS

The proportion of HIV-positive drug users who achieved ≥ 95% adherence across the studies varied widely, from 19.3 to 83.9%. Adherence rates changed over the course of HIV treatment. The factors that influenced adherence were reported as follows: stigmatization, motivation, active drug use, accessibility and conditionality of HIV and addiction care, side effects and complexity of treatment regimens, forgetfulness and non-incorporation of dosing times into daily schedules.

CONCLUSIONS

HIV-positive drug users' medication-taking is a dynamic social process that requires health professionals to assess adherence to HIV treatment on a regular basis.

Contingency Management Interventions for HIV, Tuberculosis, and Hepatitis Control Among Individuals With Substance Use Disorders: A Systematized Review

Hepatitis, HIV and tuberculosis are significant and costly public health problems that disproportionately affect individuals with substance use disorders (SUDs). Incentive-based treatment approaches (i.e., contingency management; CM) are highly effective at reducing drug use. The primary aim of this report is to review the extant literature that examines the efficacy of CM interventions for the prevention, diagnosis and treatment of hepatitis, HIV and tuberculosis among individuals with SUDs. A literature search identified 23 controlled studies on this topic. In approximately 85% of the studies, CM produced significantly better adherence to prevention, diagnosis and treatment-related medical services, with adherence rates averaging almost 35% higher among patients receiving incentives vs. control condition participants. Findings from these studies parallel the results of a meta-analysis of CM interventions for the treatment of SUDs. The results also suggest that the principles that underlie the efficacy of CM generalize across infectious disease and substance abuse treatment behaviors. The application of additional principles from the literature on CM for treatment of SUDs to interventions targeting infectious disease control would be beneficial. Further development and dissemination of these interventions has the potential to greatly impact public health.

Adherence to highly active antiretroviral therapy in Spain. A meta-analysis

OBJECTIVES

To estimate the percentage of adherence to highly-active antiretroviral therapy (HAART) in Spanish observational studies and to identify the variables associated with adherence.

METHODS

Seven electronic databases were used to locate the studies. Six inclusion criteria were established. Two coders codified the variables independently. Intercoder reliability was calculated. Publication bias was analyzed through the Begg, Egger and Trim and Fill tests. Homogeneity was evaluated using the Q test and the l² index. A random effects model was assumed to estimate both the overall percentage of adherence and to explain heterogeneity.

RESULTS

This meta-analysis included 23 observational studies, yielding a total of 34 adherence estimates. The sample was composed of 9,931 HIV-positive individuals (72% men) older than 18 years under treatment with HAART. The percentage of patients adhering to an intake of >90% of the prescribed antiretroviral drugs was 55%. Wide heterogeneity was detected (I² =91.20; 95%CI: 88.75-93.13). Adherence was mainly measured using a single strategy (47.8%), the most widely used being self-report (48.7%). In the univariate analysis, the following factors were significant: infection stages A (β=0.68, p <0.001) and B (β=-0.56, p <0.01), viral loads >200 copies/ml (β=-0.41, p <0.05) and <200 (β=0.39, p <0.05), and university education (β=-0.66, p<0.05).

CONCLUSIONS

The overall percentage of adherence was 55%, although this value may be an overestimate. Adherence was associated with infection stage A and with a viral load of <200 copies/ml.

Prediction of adherence to antiretroviral therapy: A one-year longitudinal study

The aim of this longitudinal study was to identify the determinants of adherence to antiretroviral therapy (ART) in HIV patients over a period of 12 months. A total of 376 individuals living with HIV treated with ART participated in the study. Data were collected at baseline and at three, six, nine and 12 months. Variables assessed were adherence, attitude, outcome expectancies, self-efficacy, patient satisfaction with the relationship with their physician, provision of social support, optimism, CD4 cell count, viral load and side effects. Predictors of adherence in the Generalized Estimated Equation (GEE) were: high perception of self-efficacy (OR=1.68; 95%CI 1.27-2.22), positive attitude towards taking medication (OR=1.56; 95%CI 1.18-2.06), not living alone (OR=1.47; 95%CI 1.04-2.08) and being a male (OR=2.81; 95%CI 1.47-5.34). Subsequent analysis showed that a positive attitude towards taking medication was associated with a high level of patient satisfaction with their physician, high perceived social support, being optimistic, living with HIV for five years or less and experiencing no side effects. Also, a strong sense of self-efficacy was associated with positive perception of social support, high level of patient satisfaction with their physician and not living alone. These results suggest that interventions aimed at improving adherence to ART should focus on reinforcing self-efficacy and developing a positive attitude towards taking medication.

Adherence to antiretroviral therapy among HIV-infected drug users: a meta-analysis

We conducted a meta-analysis of studies assessing adherence to highly active antiretroviral therapy (HAART) and a qualitative systematic review of factors associated with better HAART outcomes among HIV+ drug users (DU). Thirty-eight studies were considered, which analyzed 14,960 patients (11,394 HIV+ DU, 76.2%). Overall adherence (pooled percent of DU classified as adherent in each study) was 0.60 (95% CI: 0.52-0.68), similar to levels identified by studies conducted with HIV+ patients who are not drug users. Time frame used to measure adherence was an independent predictor of inter-study heterogeneity. The systematic review identified better HAART outcomes among former DU, those with less severe psychiatric conditions, those receiving opioid substitution therapy and/or psychosocial support. Patients initiating HAART with lower viral load and higher CD4 counts, and those without co-infections also had better treatment outcomes. Our findings suggest that HIV+ DU tend to be inappropriately assumed to be less adherent and unlikely to achieve desirable treatment outcomes, when compared to their non-DU cohort.

Adherence to antiretroviral therapy for human immunodeficiency virus/acquired immune deficiency syndrome among drug users: a systematic review

AIMS

Adherence to highly active antiretroviral therapy (HAART) is a key predictor of survival for human immunodeficiency virus (HIV)-infected people. Suboptimal adherence among marginalized populations such as HIV-positive drug users could be associated with clinical failure and the emergence of viral resistance.

OBJECTIVE

To conduct a systematic review of studies assessing adherence to HAART among HIV-positive drug users (DU) and identify factors associated with non-adherence to HIV treatment.

DATA SOURCES

Seven electronic databases were searched for peer-reviewed papers published in English, French, Spanish or Portuguese, from 1996 to 2007.

STUDY SELECTION AND DATA ABSTRACTION

Studies were excluded if they presented only qualitative data, were reviews themselves or assessed other populations without disaggregating data on DU. Findings on adherence were extracted and summarized.

DATA SYNTHESIS

Forty-one studies were considered, which studied a total of 15 194 patients, the majority of whom were HIV-positive DU (n = 11 628, 76.5%). Twenty-two studies assessed adherence using patient self-reports, eight used pharmacy records, three used electronic monitoring [i.e. Medication Event Monitoring Systems (MEMS) caps], six studies used a combination of patient self-report, clinical data and MEMS-caps, and two analyzed secondary data. Overall, active substance use was associated with poor adherence, as well as depression and low social support. Higher adherence was found in patents receiving care in structured settings (e.g. directly observed therapy) and/or drug addiction treatment (especially substitution therapy).

CONCLUSION

While lower than other populations-especially among users of stimulants, incarcerated DU and patients with psychiatric comorbidities-adherence to HAART among HIV-positive DU can be achieved. Better adherence was identified among those engaged in comprehensive services providing HIV and addiction treatment with psychosocial support.

The cost-effectiveness of counseling strategies to improve adherence to highly active antiretroviral therapy among men who have sex with men

OBJECTIVE

Inadequate adherence to highly active antiretroviral therapy (HAART) may lead to poor health outcomes and the development of HIV strains that are resistant to HAART. The authors developed a model to evaluate the cost-effectiveness of counseling interventions to improve adherence to HAART among men who have sex with men (MSM).

METHODS

The authors developed a dynamic compartmental model that incorporates HIV treatment, adherence to treatment, and infection transmission and progression. All data estimates were obtained from secondary sources. The authors evaluated a counseling intervention given prior to initiation of HAART and before all changes in drug regimens, combined with phone-in support while on HAART. They considered a moderate-prevalence and a high-prevalence population of MSM.

RESULTS

If the impact of HIV transmission is ignored, the counseling intervention has a cost-effectiveness ratio of $25,500 per quality-adjusted life year (QALY) gained. When HIV transmission is included, the cost-effectiveness ratio is much lower: $7400 and $8700 per QALY gained in the moderate- and high-prevalence populations, respectively. When the intervention is twice as costly per counseling session and half as effective as estimated in the base case (in terms of the number of individuals who become highly adherent, and who remain highly adherent), then the intervention costs $17,100 and $19,600 per QALY gained in the 2 populations, respectively.

CONCLUSIONS

Counseling to improve adherence to HAART increased length of life, modestly reduced HIV transmission, and cost substantially less than $50,000 per QALY gained over a wide range of assumptions but did not reduce the proportion of drug-resistant strains. Such counseling provides only modest benefit as a tool for HIV prevention but can provide significant benefit for individual patients at an affordable cost.

Early immunologic and virologic responses to highly active antiretroviral therapy and subsequent disease progression among HIV-infected injection drug users

We examined the prevalence and prognostic value of early responses to highly active antiretroviral therapy (HAART) among community-based injection drug users (IDUs) in Baltimore. Virologic (HIV RNA <1000 copies/ml) and immunologic (CD4 >500 cells/ul or increase of 50 cells/ul from the pre-HAART level) responses were examined in the 1st year of HAART initiation. Cox regression was used to examine the effect of early response on progression to new AIDS diagnosis or AIDS-related death. Among 258 HAART initiators, 75(29%) had no response, 53(21%) had a virologic response only, 38(15%) had an immunologic response only and 92(36%) had a combined immunologic and virologic response in the first year of therapy. Poorer responses were observed in those who were older, had been recently incarcerated, reported injecting drugs, had not had a recent outpatient visit and had some treatment interruption within the 1st year of HAART. In multiple Cox regression analysis, the risk of progression was lower in those with combined virologic and immunologic response than in non-responders, (relative hazard [RH], 0.32; 95% confidence interval [CI], 0.17-0.60). Those with discordant responses had reduced risk of progression compared to non-responders but experienced faster progression than those with a combined response, although none of these differences was statistically significant. Early discordant and non response to HAART was common, often occurred in the setting of injection drug use and treatment interruption and was associated with poorer survival. Interventions to reduce treatment interruptions and to provide continuity of HIV care during incarceration among IDUs are needed to improve responses and subsequent survival.

Psychiatric Illness and Virologic Response in Patients Initiating Highly Active Antiretroviral Therapy

BACKGROUND

Mental illness (MI) and substance abuse (SA) are common in HIV-positive patients. MI/SA consistently predict poorer antiretroviral adherence, suggesting that affected patients should be at higher risk of poor virologic and immunologic response to highly active antiretroviral therapy (HAART).

PARTICIPANTS

198 HAART-naive patients initiated HAART at an academic medical center serving a heterogeneous population.

METHODS

Participants were assigned a predicted probability from 0 to 1 of having each of the following: (1) any mood, anxiety, or substance use disorder; (2) clinically relevant depression; (3) alcohol abuse/dependence; and (4) drug abuse/dependence. Probabilities were based on responses to questions on an MI/SA screening instrument (Substance Abuse and Mental Illness Symptoms Screener [SAMISS]) and other clinical and sociodemographic characteristics and were derived using predictive logistic regression modeling from a separate validation study of the SAMISS compared with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnoses. Using survival analysis techniques, we assessed baseline predicted probability of psychiatric illness as a predictor of time from HAART initiation to virologic suppression (first viral load [VL] <400 copies/mL), from HAART initiation to overall virologic failure (first VL >or=400 copies/mL after suppression, time set to 0 for patients never achieving suppression), from virologic suppression to virologic rebound (first VL >or=400 copies/mL), and from HAART initiation to immunologic failure (first CD4 cell count lower than baseline).

RESULTS

A higher predicted probability of any psychiatric disorder was associated with a slower rate of virologic suppression (adjusted hazard ratio [aHR] = 0.86 per 25% increment, 95% confidence interval [CI]: 0.75 to 0.98) and a faster rate of overall virologic failure (aHR = 1.22, 95% CI: 1.06 to 1.40). Associations with other outcomes were consistent in direction but not statistically significant. Predicted probability of depression was associated with slower virologic suppression (aHR = 0.79, 95% CI: 0.63 to 0.98), and predicted probabilities of alcohol and drug abuse/dependence was associated with faster overall virologic failure (aHR = 1.37, 95% CI: 1.08 to 1.74 and aHR = 1.18, 95% CI: 1.00 to 1.39, respectively).

CONCLUSIONS

These results are consistent with an inferior virologic response to first HAART among patients with concurrent mood, anxiety, and substance use disorders, suggesting a clinical benefit to identification and treatment of psychiatric illness among patients initiating antiretroviral therapy.

A Trial of Integrated Buprenorphine/Naloxone and HIV Clinical Care

BACKGROUND

Untreated opioid dependence adversely affects the care of human immunodeficiency virus (HIV)-positive patients. Buprenorphine, a partial opioid agonist, is available for maintenance treatment of opioid dependence in HIV specialty settings. We investigated the feasibility and efficacy of integrating buprenorphine, along with 2 levels of counseling, into HIV clinical care.

METHODS

HIV-positive, opioid-dependent patients were enrolled in a 12-week pilot study and randomized to receive daily buprenorphine/naloxone treatment along with either brief physician management or physician management combined with nurse-administered drug counseling and adherence management. Primary outcomes included treatment retention; illicit drug use, assessed by urine toxicology test and self-report; CD4 lymphocyte counts; and log(10) HIV type 1 (HIV-1) RNA levels.

RESULTS

Of the 16 patients who received at least 1 dose of buprenorphine, 13 (81%) completed 12 weeks of treatment. The proportion of opioid-positive weekly urine test results decreased from 100% at baseline to 32% (month 1), 20% (month 2), and 16% (month 3). Only 4 patients reported any opioid use (in the prior 7 days) during the 12-week study. CD4 lymphocyte counts remained stable over the course of the study. The mean log(10) HIV-1 RNA level (+/- standard deviation) declined significantly, from 3.66+/-1.06 log(10) HIV-1 RNA copies/mL at baseline to 3.0+/-0.57 log(10) HIV-1 RNA copies/mL at month 3 (P<.05). No significant differences based on counseling intervention were detected. All 13 patients who completed the study continued to receive treatment in an extension phase of at least 0-15 months' duration.

CONCLUSIONS

We conclude that it is feasible to integrate buprenorphine into HIV clinical care for the treatment of opioid dependence. Patients experienced good treatment retention and reductions in their opioid use. HIV biological markers remained stable or improved during buprenorphine/naloxone treatment.

A programme of symptom management for improving quality of life and drug adherence in AIDS/HIV patients

AIM

This paper reports an evaluation of the effect of symptom management programmed on drug adherence, CD4 count and virus load and the quality of life of patients with HIV/AIDS.

BACKGROUND

Patients with HIV/AIDS have to face the long-term side effects caused by highly active antiretroviral therapy regimens. There has been little research to evaluate the influence of drug intervention side effects on self-care.

METHODS

Sixty-seven patients with HIV/AIDS were randomly assigned to one-on-one teaching, group teaching, or control groups. All those in the one-on-one and group teaching groups attended a symptom management programme once a week, followed by 3 weeks of continuity and telephone counselling. Those in the control group were offered experimental intervention at the conclusion of data collection. The Customized Adherence Self-Report Questionnaire, CD4 count and virus load, and Quality of Life Index were used to evaluate the effectiveness of the symptom management programme before and at 3 months after the intervention.

RESULTS

Median differences on the Customized Adherence Self-Report Questionnaire, CD4 count and virus load, and quality of life in both experimental groups were statistically significantly better than in the control group.

CONCLUSIONS

The symptom management programme can increase self-care ability in managing medication side effects in patients with HIV/AIDS.

Antiretroviral adherence and HIV treatment outcomes among HIV/HCV co-infected injection drug users: the role of methadone maintenance therapy

OBJECTIVE

We examined the association of methadone maintenance therapy (MMT) with highly active antiretroviral therapy (HAART) adherence and HIV treatment outcomes among a cohort of HIV/HCV co-infected injection drug users (IDUs).

METHODS

We obtained demographic, drug use, and addiction care history from the Vancouver Injection Drug User Study (VIDUS), which is an open cohort study of IDUs. The questionnaires were longitudinally linked to the British Columbia HIV/AIDS Drug Treatment Program to obtain HAART adherence and HIV treatment outcome data. There were 278 VIDUS participants who accessed HAART from August 1, 1996 to November 24, 2003. We constructed longitudinal logistic models using generalized estimating equations to examine the independent associations between methadone maintenance therapy and the following outcomes: HAART adherence; plasma HIV-1 RNA suppression; and CD4 cell rise of 100cells/mm(3).

RESULTS

Among participants who reported at least weekly heroin use, MMT was independently associated with lower odds of subsequent weekly heroin use during the follow-up period (adjusted odds ratio; 95% confidence interval [AOR; 95% CI]: 0.24; 0.14-0.40). We also found that MMT was positively associated with adherence (AOR 1.52; 95% CI 1.16-2.00), HIV-1 RNA suppression (AOR 1.34; 95% CI 1.00-1.79), and CD4 cell count rise (AOR 1.58; 95% CI 1.26-1.99).

CONCLUSIONS

Among HIV/HCV co-infected IDUs on HAART, enrollment in MMT was associated with reduced heroin use, and improved adherence, HIV-1 RNA suppression and CD4 cell count response. Integrating opiate addiction care and HIV care may provide improved health outcomes for this vulnerable population and should be further explored.

Prevalence of DSM-IV-Defined Mood, Anxiety, and Substance Use Disorders in an HIV Clinic in the Southeastern United States

BACKGROUND

Mood and anxiety disorders, particularly depression, and substance abuse (SA) commonly co-occur with HIV infection. Appropriate policy and program planning require accurate prevalence estimates. Yet most estimates are based on screening instruments, which are likely to overstate true prevalence.

SETTING

Large academic medical center in Southeast.

PARTICIPANTS

A total of 1,125 patients, representing 80% of HIV-positive patients seen over a 2.5-year period, completed the Substance Abuse-Mental Illness Symptoms Screener, a brief screening instrument for probable mood, anxiety, and SA disorders. Separately, 148 participants in a validation study completed the Substance Abuse-Mental Illness Symptoms Screener and a reference standard diagnostic tool, the Structured Clinical Interview for DSM-IV.

METHODS

Using the validation study sample, we developed logistic regression models to predict any Structured Clinical Interview for DSM-IV mood/anxiety disorder, any SA, and certain specific diagnoses. Explanatory variables included sociodemographic and clinical information and responses to Substance Abuse-Mental Illness Symptoms Screener questions. We applied coefficients from these models to the full clinic sample to obtain 12-month clinic-wide diagnosis prevalence estimates.

RESULTS

We estimate that in the preceding year, 39% of clinic patients had a mood/anxiety diagnosis and 21% had an SA diagnosis, including 8% with both. Of patients with a mood/anxiety diagnosis, 76% had clinically relevant depression and 11% had posttraumatic stress disorder.

CONCLUSIONS

The burden of psychiatric disorders in this mixed urban and rural clinic population in the southeastern United States is comparable to that reported from other HIV-positive populations and significantly exceeds general population estimates. Because psychiatric disorders have important implications for clinical management of HIV/AIDS, these results suggest the potential benefit of routine integration of mental health identification and treatment into HIV service sites.

Role of the HIV/AIDS case manager: analysis of a case management adherence training and coordination program in North Carolina

Highly active antiretroviral therapy (HAART) adherence rates of 90%-95% or more are required to be effective at treating the virus and preventing drug resistance. From both a medical and public health perspective, it is essential that HIV-positive clients strictly adhere to antiretroviral treatment regimens. One promising approach to promoting optimal adherence rates among HIV-positive individuals is training and reimbursing case managers to provide adherence coordination services to HIV-positive clients. In this study, a sample of 16 HIV/ AIDS case managers from agencies across North Carolina participated in a Case Management Adherence Training and Coordination Program for a 3-month period. After case manager training, case managers enrolled 1-4 of their existing clients, who met eligibility criteria, to receive the adherence coordination program. Data were analyzed from focus group interviews and individual interviews conducted with case manager participants; their respective client care plans were also analyzed to identify primary barriers and strategies reported by case managers. Although case managers perceived themselves to be well positioned to provide adherence coordination services for their HIV-positive clients, they also identified barriers that they face in providing these services, including lack of reimbursement for their time, inadequate training, and insufficient knowledge of HIV/AIDS and medications. The findings of this study suggest that, with appropriate training and reimbursement, HIV/AIDS case managers can play a pivotal role in promoting and improving client adherence to antiretroviral medications.

HAART with didanosine once versus twice daily: adherence and efficacy

BACKGROUND

Highly active antiretroviral therapy (HAART) containing didanosine taken twice daily was compared with HAART containing didanosine taken once daily in terms of adherence and efficacy.

METHOD

This was a self-controlled prospective cohort study, carried out in a tertiary level hospital. A total of 49 HIV-infected patients were included. They were prescribed HAART according to guidelines. After six months taking HAART containing didanosine twice daily, patients continued with the same regimen of HAART although once daily. Thereafter they were followed up for a further nine months. Adherence and virological efficacy were assessed at three-month intervals, for a total of six times, in every patient.

RESULTS

Overall, adherence was poor, with only 19 patients (39%) showing adequate adherence for all six visits. Adequate adherence was observed in 29 patients (59%) three months before didanosine switching, and in 37 patients (75%) three months after didanosine switching (P=0.034). Pooled HIV RNA results of the first three visits were higher than the same results of the last three visits (P=0.05).

CONCLUSIONS

Non-adherence is common among patients who take HAART. Simplification of regimens is useful to improve adherence and efficacy.

Cost-effectiveness of screening for HIV in the era of highly active antiretroviral therapy

BACKGROUND

The costs, benefits, and cost-effectiveness of screening for human immunodeficiency virus (HIV) in health care settings during the era of highly active antiretroviral therapy (HAART) have not been determined.

METHODS

We developed a Markov model of costs, quality of life, and survival associated with an HIV-screening program as compared with current practice. In both strategies, symptomatic patients were identified through symptom-based case finding. Identified patients started treatment when their CD4 count dropped to 350 cells per cubic millimeter. Disease progression was defined on the basis of CD4 levels and viral load. The likelihood of sexual transmission was based on viral load, knowledge of HIV status, and efficacy of counseling.

RESULTS

Given a 1 percent prevalence of unidentified HIV infection, screening increased life expectancy by 5.48 days, or 4.70 quality-adjusted days, at an estimated cost of 194 dollars per screened patient, for a cost-effectiveness ratio of 15,078 dollars per quality-adjusted life-year. Screening cost less than 50,000 dollars per quality-adjusted life-year if the prevalence of unidentified HIV infection exceeded 0.05 percent. Excluding HIV transmission, the cost-effectiveness of screening was 41,736 dollars per quality-adjusted life-year. Screening every five years, as compared with a one-time screening program, cost 57,138 dollars per quality-adjusted life-year, but was more attractive in settings with a high incidence of infection. Our results were sensitive to the efficacy of behavior modification, the benefit of early identification and therapy, and the prevalence and incidence of HIV infection.

CONCLUSIONS

The cost-effectiveness of routine HIV screening in health care settings, even in relatively low-prevalence populations, is similar to that of commonly accepted interventions, and such programs should be expanded.

Outpatient pharmacy care and HIV viral load response among patients on HAART

Adherence to highly active antiretroviral therapy (HAART) is necessary to achieve long-term effectiveness. The impact of HIV/AIDS-specific pharmacy services on patient adherence and HIV viral suppression is currently not well described. This study aimed to compare the impact of differing levels of HIV-pharmacy care on adherence and time to HIV viral suppression among participants on HAART enrolled in a population-based HIV/AIDS drug treatment programme in British Columbia. We performed a retrospective observational study of 788 treatment-naïve patients who started HAART between August 1997 and July 2000 and were followed until 31 March 2002. The degree of outpatient pharmacy care was defined according to pharmacy dispensing site for the participants' first prescription of HAART: highest at the AIDS-tertiary care hospital outpatient pharmacies, intermediate at HIV/AIDS drug treatment programme funded off-site pharmacies and lowest at family physician's offices. Cox-proportional hazard models examined the independent effect of pharmacy dispensing site on time to two consecutive HIV viral suppressions controlling for other prognostic factors including physicians' experience, age, gender, injection drug use, use of therapy containing NNRTI versus PI, adherence >90%, AIDS diagnosis at baseline, baseline CD4 cell count and HIV viral load. The median time on antiretrovirals was 28 months (IQR=14-38). There were 489 (62.1%) participants who obtained their medications from the AIDS-tertiary care outpatient pharmacies; 98 (12.4%) from off-site pharmacies and 201 (25.5%) from their physicians' offices. The proportion of patients exhibiting >90% adherence to treatment was observed to be higher among patients receiving their HAART at the AIDS-tertiary care pharmacies compared to off-site pharmacies and to physicians' offices (70.4, 59.2 and 55.7%, respectively; p=0.0001). After adjusting for other prognostic factors, subjects who were first dispensed medications from the AIDS-tertiary care pharmacy were 1.42 times (CI: 1.10-1.84) more likely to achieve HIV viral suppression than those getting their medications from off-site pharmacies and physicians' offices. Providing regular outpatient pharmacy care is independently associated with improved HIV viral load response through enhanced adherence to HAART. Standardization of pharmacy practices for dispensing HAART may improve outcomes for patients who receive their HIV medications from other non-tertiary care pharmacy sites.

Challenges facing health professionals caring for HIV-infected drug users

Although injection drug use accounts for only 5% to 10% of cumulative HIV infections globally, it is a more efficient way of spreading HIV than sexual intercourse. HIV epidemics among injection drug users (IDUs) have a potential for rapid spread of the virus within the IDU community and outward into the general population. Effective interventions addressing this mode of HIV transmission are needed because part of a comprehensive strategy to curb the spread of HIV infection. IDUs, often marginalized, pose serious health challenges that can no longer be overlooked. Health care providers need to familiarize themselves with these challenges in order to meet the needs of this disenfranchised population. Providers need to have a clear understanding of targeted behavior and their patients' environmental context. Efforts must be made to foster healthy behavior among IDUs to assist them in managing their infection effectively and become productive members of society. This paper reviews these challenges and outlines selected models that may assist health care providers in fostering behavior changes among HIV-positive injection drug users.

Adherence to directly observed antiretroviral therapy among human immunodeficiency virus-infected prison inmates

Directly observed therapy (DOT) for human immunodeficiency virus (HIV) infection is commonly used in correctional settings; however, the efficacy of DOT for treating HIV infection has not been determined. We prospectively assessed adherence to antiretroviral therapy regimens among 31 HIV-infected prison inmates who were receiving >or=1 antiretrovirals via DOT. Adherence was measured by self-report, pill count, electronic monitoring caps, and, for DOT only, medication administration records. Overall, median adherence was 90%, as measured by pill count; 86%, by electronic monitoring caps; and 100%, by self-report. Adherence, as measured by electronic monitoring caps, was >90% in 32% of the subjects. In 91% of cases, adherence, as measured by medication administration records, was greater than that recorded by electronic monitoring caps for the same medications administered by DOT. Objective methods of measurement revealed that adherence to antiretroviral regimens administered wholly or in part by DOT was <or=90% in more than one-half of the patients. Different methods used to measure adherence revealed significantly different levels of adherence. These findings suggest that use of DOT does not ensure adherence to antiretroviral therapy.

Impaired virologic response to highly active antiretroviral therapy associated with ongoing injection drug use

Injection drug users who continue to use drugs may not respond to highly active antiretroviral therapy (HAART) as well as other HIV-infected individuals, even after adjusting for a reliable measure of adherence. We therefore compared the virologic response among participants in a population-based HIV/AIDS Drug Treatment Program in British Columbia, Canada, by injection drug use activity. Participants who were HIV infected and naive to antiretroviral therapy and who were prescribed antiretroviral treatment between August 1996 and December 2000 were eligible for this study. They were classified as current, former, or non-injection drug users. The main outcome was having two consecutive HIV-1 RNA levels less than 500 copies/mL. We used logistic regression to adjust for baseline HIV-1 RNA, type of antiretroviral regimen (2 nucleosides + nonnucleoside reverse transcriptase inhibitor versus 2 nucleosides + protease inhibitor), duration of therapy (months), adherence (derived from refill compliance data), and age. A total of 578 participants were first prescribed HAART during the study period. Among them, 78 (13%) were current injection drug users, 96 (17%) were former injection drug users, and 404 (70%) never injected drugs. In the multivariable logistic regression, relative to non-drug users, current injection drug users were significantly less likely to suppress their HIV-1 RNA (adjusted OR [AOR] = 0.30, 95% CI: 0.13-0.67), and former injection drug users were not significantly different from non-drug users (AOR = 0.56, 95% CI: 0.24-1.34). There was a significant interaction between drug use and adherence. In the analyses stratified by drug use, the adherence of former and non-drug users was positively associated with HIV-1 RNA suppression (AOR = 1.33, 95% CI: 1.14-1.55), whereas for current drug users, it was not (AOR = 1.07, 95% CI: 0.87-1.33). Current injection drug users were less likely to achieve HIV-1 RNA suppression compared with non-drug users. Adherence as measured by pharmacy refill compliance was not a reliable measure in this subpopulation.

Failure to maintain adherence to HAART in a cohort of French HIV-positive injecting drug users

The study, carried out in the French MANIF 2000 cohort of HIV positive patients contaminated through injecting drug use, assessed the impact of patients' sociodemographic and psychological characteristics, behaviors toward drug abuse, and antiretroviral treatment characteristics on the maintenance of adherence to HAART (highly active antiretroviral therapies). A total of 96 patients (30 men and 66 women), who were initially adherent at their first visit after HAART prescription, were considered for analysis. Among these 96 patients, 22 (22.9%) experienced adherence failure defined as a self-reported, non-adherence behavior at any visit before the 18th month of treatment. Logistic regression showed that lack of a stable relationship, active drug injection, and depression were independently associated with adherence failure. Patients' counseling for facilitating maintenance of adherence to HAART over time should focus on prevention of drug use, provision of social support and consider the potential impact of difficulties with treatment on psychological well-being.

[Adherence to antiretroviral drug therapy. A systematic review]

BACKGROUND

We performed a systematic review of the medical literature in order to determine the level of adherence to antiretroviral therapy and its relation with the social, demographic, and clinical characteristics of patients.

METHOD

Systematic search of published primary studies in MEDLINE, EMBASE and IME and review of reports presented in main congresses related to infectious diseases and AIDS. Observational and intervention studies carried out in adult patients between 1990 and the first semester of 2001 were selected following descriptive and quality criteria. Both English language and Spanish language reports were analyzed.

RESULTS

30 studies fulfilled previously established requirements. Most studies show high adherence levels between 50% and 80% patients, with a range between 28% and 82%. In univariate or multivariate analyses, factors associated with worse adherence levels were as follows: females, younger people, low education level, low income, active drug consumption, lack of self-perception of the efficacy of antiretroviral agents, stress and lack of motivation, high number of tablets and complexity of administration guidelines. Most prospective studies show a good correlation between adherence and control of HIV infection determined by the measurement of the viral load.

CONCLUSIONS

The number of primary studies with methodological quality is limited and future works must be performed under strict design conditions. Most studies show that a high proportion of patients, between 20% and 50%, do not have optimal levels of adherence. Patients with higher adherence levels exhibit greater clinical effectivity. Social, demographic, psychological and other factors related to the lack of adherence must be taken into account in order to improve the compliance in these patients.

Adherence to highly active antiretroviral therapies (HAART) in HIV-infected patients: from a predictive to a dynamic approach

To-date, most socio-behavioural research about HTV-infected patients' adherence to highly active antiretroviral therapies (HAART) has been based on cross-sectional studies. The French APROCO cohort gave us the opportunity to conjointly analyse the relationships between short-term adherence to HAART and HIV-infected patients' characteristics before initiation of treatment on the one hand, factors related to patients' subjective experience with HAART on the other hand. At the fourth-month follow-up visit (M4) after first prescription of HAART (M0), 26.7% of our sample of 445 patients self-reported non-adherence behaviour. Some patients' characteristics at M0 (younger age, poor housing conditions, lack of social support, and problems of adherence with previous antiretroviral regimens) were related to non-adherence at M4 in multivariate analysis. Non-adherence at M4 was, however, also related to the evolutions that affected a number of factors between M0 and M4: levels of depression, symptoms associated with treatment side effects, perception of individual state of health, beliefs towards effectiveness and toxicity of HAART. increases in alcohol and tobacco consumption, as well as contacts with other physicians than hospital HAART prescribers. Our prospective study brings additional evidence that even short-term non-adherence cannot be reliably predicted on the sole basis of a few a priori patient characteristics that clinicians could easily identify before initiation of HAART. It suggests that a dynamic approach to adherence, continuously monitoring the impact of experience with HAART on patients' daily lives, is needed for improving management of HIV/AIDS care.

Factors related to virologic failure among HIV-positive injecting drug users treated with combination antiretroviral therapy including two nucleoside reverse transcriptase inhibitors and nevirapine

Treatment strategies in human immunodeficiency virus (HIV)-positive active injecting drug users (IDUs) must take into account their lifestyles, that often result in low adherence to therapy. The nonnucleoside reverse transcriptase inhibitors (NNRTI) offer simpler treatment regimens, but the appearance of drug resistance during treatment failure may cause high levels of cross-resistance to all NNRTIs. We adopted a combination therapy of two NRTIs and nevirapine (NVP) for treatment of IDU patients to evaluate its feasibility in such patients. From October 1998 to December 1999, demographic, clinical, and laboratory data from 80 IDUs on this regimen were collected. Fisher's exact test, Kaplan Meier method, and Cox model were used for statistical analysis. Overall, 20 IDUs discontinued the treatment because of side effects and 20 IDUs experienced treatment failure. Considering the treatment failure as an end point, 55.6% (95% confidence interval [CI]: 37.9%-72.6%) of patients was still undergoing treatment after 12 months compared to 44.6% (31.8%-58.6%) when discontinuation was also taken into account. An increasing trend over time was observed in the CD4+ lymphocyte count, among failing and nonfailing IDUs. By multivariate analysis, baseline HIV-RNA, treatment breaks and low adherence and active injecting drug use turned out to be significantly associated with treatment failure. Our results show that continuing injecting drug use and treatment breaks are the main factors that can lead to treatment failure in IDUs and easily to NNRTI class resistance.

The dynamic of adherence to highly active antiretroviral therapy: results from the French National APROCO cohort

OBJECTIVES

Our objective was to describe the evolution of adherence to highly active antiretroviral therapy (HAART) over a 20-month period and its relationship with virologic success.

METHODS

Self-reported adherence, clinical, and virologic data were collected 4 (M4), 12 (M12), and 20 (M20) months after initiation of a protease inhibitor-containing regimen in the French APROCO cohort. At each visit, patients were classified as nonadherent, moderately, or highly adherent, and HIV plasma RNA was determined.

RESULTS

Among the 762 patients who were regularly followed until M20, the 436 patients who answered to all questionnaires, including adherence measurement, were selected for the analysis. The proportion of highly adherent patients was 55.7%, 62.2%, and 60.3% at M4, M12, and M20, respectively. A total of 137 patients (31.4%) was "always," 225 (51.6%) "sometimes," and 74 (17.0%) "never" "highly adherent" during follow-up. After multiple adjustment for known baseline predictors, virologic success after 20 months of HAART was more likely achieved in patients who were always (odds ratio [OR] 95% confidence interval [CI], 3.02 [1.64-5.58]) or sometimes (OR [95% CI], 2.15 [1.24-3.74]) "highly adherent."

CONCLUSION

Adherence behavior is a dynamic process. Continued adherence was associated with better response to therapy and should be encouraged to reduce the risk of virologic failure.

Adherence, side effects and efficacy of stavudine plus lamivudine plus nelfinavir in treatment-experienced HIV-infected patients

OBJECTIVES

To evaluate adherence, side effects and efficacy of a modality of highly active antiretroviral therapy (HAART) in HIV-infected patients.

METHODS

In a cohort, prospective study, 65 previously treated patients received stavudine plus lamivudine plus nelfinavir. Fifty-three participants (81%) had a history of intravenous drug use. Patients were evaluated at 3-month intervals. The association of adherence with demographic variables, hepatitis C virus infection, number of stopped antiretroviral regimens, HIV RNA level, CD4 cell count, and adverse effects to drugs was assessed.

RESULTS

After a median follow-up of 12 months, 30 participants (46%) showed adequate adherence in all visits. An association was observed between adherence and female sex: 18 of 47 men (38%) vs. 12 of 18 women (67%) presented adequate adherence in all visits (P=0. 0416). An association was also observed between adherence and low baseline HIV RNA level (P=0.0229). Discontinuation of treatment took place because of refusal to take medication in 11 participants (17%) and because of side effects in seven participants (11%). Undetectable HIV RNA level was achieved in 26 patients (40%) at 3 months and in lower percentages at months 6, 9 and 12.

CONCLUSIONS

Overall adherence to the employed HAART regimen was poor. Female sex and low baseline HIV RNA were associated with better adherence. Refusal to take medications and side effects were the main reasons to stop therapy. At 3 months' follow-up, virological efficacy was achieved in 40% of patients.

Predictors of self-reported adherence and plasma HIV concentrations in patients on multidrug antiretroviral regimens

BACKGROUND

Adherence to prescribed medications is a central feature of good clinical HIV care, but little is known about the factors associated with multidrug antiretroviral adherence, or about how such adherence is related to plasma HIV suppression.

METHODS

We collected data from 133 HIV-infected adults receiving antiretroviral therapy. Study subjects completed customized adherence self-report instruments and provided blood samples to measure plasma HIV-1 RNA concentrations and CD4+ lymphocyte counts. Regression models were used to determine the independent predictors of antiretroviral adherence and plasma HIV concentration, and the relationships between the two.

RESULTS

Adherence was poor (average, <80% antiretrovirals/day) in 28% (95% confidence interval [CI], 20%-36%), fair (80%-99% per day) in 23% (95% CI, 15%-30%), and excellent (100% per day) in 50% (95% CI, 41%-58%) of study subjects. Mean decreases in HIV-1 concentration from highest-ever levels were 1.3, 1.6, and 2.0 log10 copies/ml in these three groups, respectively (chi2; p < .02). Two-stage least squares regression demonstrated a -1.3 log difference in viral load associated with each category improvement in adherence. In multivariate models, confidence in medication-taking ability, or perceived self-efficacy, and convenience of the medication regimen, or "fit" with routine and daily activities, were also associated with greater medication adherence (odds ratios [OR] 5.3; 95% CI, 2.4-11.8, and 9.0; 95% CI, 1.8-45.3, respectively). The latter was also independently associated with a lower plasma HIV concentration (p < .02).

CONCLUSIONS

Nonadherence to combination antiretroviral medications is common and is associated with increased levels of plasma HIV. Programs and clinical efforts to improve medication taking should strive to integrate medications better into patients' daily routines and to improve patients' confidence in their ability to take medications correctly.