Non-adherence to highly active antiretroviral therapy predicts progression to AIDS

Patient-clinician relationships and treatment system effects on HIV medication adherence

The study objectives were to determine the impact of the patient-clinician relationship on patient adherence to HIV medication, to identify which aspects of the patient-clinician relationship and the treatment system influenced adherence, and to determine which of these variables remained important when the impact of mental distress and substance abuse were considered. The design was a cross-sectional study using a sample of 120 HIV+ clinic patients. The Primary Care Assessment Survey (PCAS) assessed the clinician-patient relationship and the treatment system. The Composite International Diagnostic Inventory-Short Form (CIDI-SF) screened for mental disorders, and the Brief Substance Abuse History Form measured recent and remote substance use. Patient adherence was assessed using five markers including 3 interview-elicited self-reports, 1 medical chart review, and 1 summary score. Logistic regression analyses identified independent predictors of each adherence behavior. PCAS scores contributed to all five models, and their effects persisted when mental distress and substance abuse were considered. Adherence behaviors are explained by a variety of factors and should be assessed using multiple methods. Further study to illuminate the mechanisms of action of the clinician-patient relationship on adherence to HIV medication is warranted.

Adherence, stereotyping and unequal HIV treatment for active users of illegal drugs

Adherence to antiretroviral therapy promotes viral suppression and extends the lives of individuals with HIV, yet illegal drug users are underrepresented among eligible persons receiving HIV treatment. One explanation for this is the assumption that drug users are less capable than others of adhering to complicated medication regimens. This paper investigates this assumption by making explicit a number of its underlying propositions and examining them in light of data collected from 52 active drug users living in and around Boston, USA, who were taking highly active antiretroviral therapy for HIV (HAART). The propositions are: (1) drug users lead "chaotic" lives; (2) active drug users are always using drugs; (3) being under the influence of drugs precludes taking medications as prescribed; and (4) drug users are intrinsically different from non-users in the lives they lead and the problems they face. Data collection consisted of a series of qualitative interviews with each participant. An analytic approach informed by grounded theory was used to construct thematic content categories from the data. Results revealed stability and control as well as "chaos" in the lives of study participants. Frequency of drug use varied considerably. Using did interfere with adherence, but not in every circumstance or all cases. Not "carrying" medications, competing priorities, and re-defining regimens were the most salient of a number of non-drug-use-related obstacles observed. Documentation of patterns of variation in corresponding data highlights the stereotypical quality of the propositions. Stereotyping risks overemphasis on drug use as a barrier to adherence for active users, and underemphasis on non-drug-use-related obstacles. Adherence capabilities of users, in contrast to inadequacies, are also obscured through stereotyping. As a medium for stigmatization, stereotyping may contribute to unequal treatment for drug users and other populations living with HIV.

Impact of an adherence clinic on behavioral outcomes and virologic response in treatment of HIV infection: A prospective, randomized, controlled pilot study

OBJECTIVE

The aim of this randomized, controlled pilot study was to examine the impact of a pharmacist operated adherence clinic on adherence to highly active antiretroviral therapy (HAART) and viral suppression in patients with HIV over 28 weeks.

METHODS

Consecutive eligible patients initiating HAART at an indigent-care clinic were randomized to an adherence clinic or to standard care (information provided by physician or nurse practitioner) for education and monitoring. Group assignment was stratified before randomization according to regimen complexity and potential tolerability. Adherence (electronic monitoring and patient self-report) and viral load (reverse-transcription polymerase chain reaction) were assessed at weeks 4, 16, and 28.

RESULTS

Thirty-three randomized patients (adherence clinic, n = 16; standard care, n = 17) comprised the intent-to-treat population. The groups were well-matched for demographics and antiretroviral regimen. The median age was 38.0 years in both groups. Most patients were male (85%), had previously used HAART (78%), and had an AIDS diagnosis (79%). Mean (SD) adherence at weeks 4, 16, and 28 was 86% (27%), 77% (28%), and 74% (31%) in the adherence clinic group versus 73% (32%), 56% (39%), and 51% (41%) in the standard care group (week-16 difference, 21% [90% CI, 1%-42%]; week-28 difference, 23% [90% CI, 1%-44%]). Sixty-nine percent of patients in the adherence clinic group took their medication on schedule versus 42% in the standard care group (P = 0.025); mean decline in adherence from weeks 4 to 28 was 12% in the adherence clinic group (P = 0.15) versus 22% in the standard care group (P = 0.002). HIV-1 RNA levels were <400 copies/mL at weeks 4, 16, and 28 in 63%, 100%, and 94% of the adherence clinic group and 29% (P = NS), 71% (P = 0.04), and 65% (P = NS) of the standard care group.

CONCLUSIONS

In this preliminary trial, an adherence clinic model improved adherence to HAART and virologic response over 28 weeks in the patients studied.

Depression and Clinical Progression in HIV-Infected Drug Users Treated with Highly Active Antiretroviral Therapy

Objective

To disentangle the impact of adherence from that of injecting drug status and depressive syndrome on HIV clinical progression in a cohort of highly active anti-retroviral therapy (HAART)-treated HIV patients infected through drug use.

Design

MANIF 2000 is a French cohort of HIV-infected drug users with scheduled medical visits every 6 months. Only patients enrolled in the MANIF 2000 cohort who had a CD4 cell count >200 cells/μl at HAART initiation were selected. The follow-up period included all post-HAART initiation visits.

Methods

HIV clinical progression was defined as either AIDS-related death or reaching a CD4 level <200 cells/μl. Adherence was assessed using a self-administered questionnaire and a structured face-to-face interview. Depressive symptoms were evaluated by a Center for Epidemiologic Studies Depression Scale (CES-D) score at each visit. Cox proportional hazards model was used to calculate crude and adjusted relative hazards and 95% confidence intervals and thus identify independent predictors of clinical progression.

Results

Of the 305 HAART-treated patients in the cohort, 243 had CD4 cell count >200 cells/μl at HAART initiation. At the first visit after HAART initiation, median CD4 cell count was 466 cells/μl and 45% had undetectable viral load. Injecting drug users accounted for 17% of the study group. Over the follow-up period, 32 patients experienced HIV clinical progression. Probable depression was encountered in 46% of patients and non-adherence in 31% of the sample. After adjustment on baseline CD4 cell count, predictors of clinical progression were: having a higher level of cumulative non-adherence over the follow-up period [HR (95% CI)=1.2 (1.1–1.3) per 10% increase] and having a high score of depressive symptoms following HAART initiation [HR (95% CI)=5.3 (2.21–3.0)]. Conclusions: Although depressive syndrome is known to influence non-adherence behaviours that are amongst the major reasons for clinical progression, it is also a predictor of clinical progression in HIV-infected intravenous drug users on HAART, independently of non-adherence behaviours. HIV care providers should be more sensitive to depressive symptoms in order to detect them early and supply HIV patients with specific care. Further research is needed to determine whether treating depressive symptoms may improve adherence and thus delay disease progression and mortality.

The HIV epidemic among individuals with mental illness in the United States

People with depression and other mental illness comprise a growing proportion of individuals living with HIV in the United States; at the same time, the prevalence of HIV among mentally ill individuals is at least seven times higher than in the general population. Individuals with mental illness are particularly vulnerable to infection with HIV because of several factors, including the higher prevalence of poverty, homelessness, high-risk sexual activities, drug abuse, sexual abuse, and social marginalization found in this population. Nevertheless, mentally ill individuals are often not screened for HIV and may not be appropriately targeted in current HIV prevention efforts. Moreover, despite widespread access to antiretroviral treatment in the United States, HIV outcomes among mentally ill individuals continue to be poor. This disparity can be explained by several interrelated factors, including lower rates of highly active antiretroviral therapy (HAART) utilization, lower rates of adherence to HAART, and immunologic changes associated with mental illness itself. We need to improve our design of prevention, screening, and treatment programs to better reach individuals with comorbid HIV and mental illness.

Gender differences in factors associated with adherence to antiretroviral therapy

OBJECTIVE

To identify gender differences in social and behavioral factors associated with antiretroviral adherence.

DESIGN

Prospective cohort study.

SETTING

Methadone maintenance program.

PARTICIPANTS

One hundred thirteen HIV-seropositive current or former opioid users.

MEASUREMENTS AND MAIN RESULTS

Participants were surveyed at baseline about social and behavioral characteristics and at monthly research visits about drug and alcohol use and medication side effects. Electronic monitors (MEMS) were used to measure antiretroviral adherence. Median adherence among women was 27% lower than among men (46% vs. 73%; P < .05). In gender-stratified multivariate models, factors associated with worse adherence in men included not belonging to an HIV support group (P < .0001), crack/cocaine use (P < .005), and medication side effects (P = .01). Among women, alcohol use (P = .005), heroin use (P < .05), and significant medication side effects (P < .005) were independently associated with worse adherence. In a model including both men and women, worse adherence was associated with lack of long-term housing (P < .005), not belonging to any HIV support groups (P < .0005), crack or cocaine use (P < .01), and medication side effects (P < .0005). In addition, worse adherence was associated with the interaction between female gender and alcohol use (P < or = .05).

CONCLUSIONS

In this cohort of current and former opioid users, gender-stratified analysis demonstrated that different social and behavioral factors are associated with adherence in men and women. Among both men and women, worse adherence was associated with lack of long-term housing, not belonging to an HIV support group, crack/cocaine use, and medication side effects. Among women only, alcohol use was associated with worse adherence.

Health-related quality of life among men with HIV infection: effects of social support, coping, and depression

In a prospective cohort study, baseline data were collected on 226 males with HIV infection attending three infectious disease clinics in a southern state. As a result of advances in HIV treatment, understanding the association between psychosocial factors and health-related quality of life has become an important area of study. The purpose of this study was to assess the total effects of social support and coping as well as the direct and indirect effects of these factors through depression on health-related quality of life. Subjects were interviewed and answered the following standardized questionnaires: The HIV Cost and Services Utilization Study tool, Coping with HIV Questionnaire, Social Support Appraisals Scale, and Centers for Epidemiological Studies Depression instrument. Path models with strictly ordered relationships were fitted to study the effects of the psychosocial variables on each quality of life subscale. We found that coping and social support had total effects on some, but not all dimensions of health-related quality of life, whereas depression was associated with all dimensions of health-related quality of life. Furthermore, the effects of both social support and coping were mainly through the intermediate variable, depression. In the era of highly active antiretroviral therapy (HAART), when quality of life issues are of paramount importance, strategies to improve social support, coping, and particularly, depressive symptoms are strongly encouraged.

Adherence to antiretroviral therapy in HIV-infected adults in Soweto, South Africa

Little is known about achievable levels of antiretroviral treatment (ART) adherence in resource-limited settings. We conducted a cross-sectional study of adherence among patients at Chris Hani Baragwanath Hospital's Adult HIV Clinic in Soweto, South Africa. Adherence was assessed using a 1-month, self-report questionnaire and was calculated as a ratio of doses taken to doses prescribed. The 66 patients studied had a mean age of 36.1 years, a median duration of ART use of 18 months, and an overall baseline median CD4(+) cell count of 200/mm(3) (IQR: 114-364). The adherence reported by these patients for the previous month was >95% for 58 patients (88%), 90-95% for 6 (9%) and, < 90% for 2 (3%). The main reasons given for missing doses were being away from home (30%), difficulty with the dosing schedules (23%), and running out of pills (12%). Adherence decreased considerably with fear of being stigmatized by the sexual partner (OR = 0.13 95%, CI 0.02-0.70). Plasma HIV RNA levels were <400 copies/ml in the majority of patients (73% of those with adherence >95% and 88% of patients with < or =95% adherence) and the overall median CD4(+) cell count rose to 324/mm(3) (IQR: 193-510). High adherence and viral suppression are achievable for a significant proportion of HIV-infected patients taking ART in a resource-limited area such as Soweto, South Africa. Strategies to maximize adherence in this setting should emphasize ready access to affordable and simple ART regimens, as well as HIV education programs to help increase awareness and decrease disease stigmatization.

Adherence to highly active antiretroviral therapy in the homeless population in San Francisco: a prospective study

BACKGROUND

We examined adherence to highly active antiretroviral therapy (HAART) in the homeless population, a population thought to be at high risk for poor adherence to therapy and for development of drug-resistant strains of human immunodeficiency virus (HIV).

METHODS

We performed a 12-month prospective study of 148 persons receiving HAART who were identified in a stratified screening of the homeless and marginally housed. We sampled in lunch lines, shelters, and hotels in 3 neighborhoods of San Francisco, California. We used pill counts at unannounced home visits as the primary measure of adherence.

RESULTS

Of 148 individuals sampled, 46 (31%) discontinued HAART during the study. Average adherence in the group of those who discontinued HAART was 51%, and 9% of these subjects had undetectable virus loads (i.e., <400 copies/mL) at the last follow-up visit. Predictors of discontinuation of therapy were depressive symptoms, injection drug use, African American ethnicity, and early poor adherence. Of 148 subjects, 102 (69%) continued to receive HAART throughout the study period. Average adherence in the group of those who continued to receive HAART was 74%, and 55% of these subjects had undetectable virus loads at the last follow-up visit. Predictors of lower average adherence in this group were African American ethnicity and use of crack cocaine; men who had sex with men had higher adherence.

CONCLUSIONS

One-third of homeless and marginally housed persons receiving HAART discontinued therapy during the follow-up period and would benefit from adherence interventions directed at sustaining therapy; two-thirds continued to receive therapy at adherence levels comparable to those found with other clinical populations.

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.

The HIV epidemic among individuals with mental illness in the United States

People with depression and other mental illness comprise a growing proportion of individuals living with HIV in the United States; at the same time, the prevalence of HIV among mentally ill individuals is at least seven times higher than in the general population. Individuals with mental illness are particularly vulnerable to infection with HIV because of several factors, including the higher prevalence of poverty, homelessness, high-risk sexual activities, drug abuse, sexual abuse, and social marginalization found in this population. Nevertheless, mentally ill individuals are often not screened for HIV and may not be appropriately targeted in current HIV prevention efforts. Moreover, despite widespread access to antiretroviral treatment in the United States, HIV outcomes among mentally ill individuals continue to be poor. This disparity can be explained by several interrelated factors, including lower rates of highly active antiretroviral therapy (HAART) utilization, lower rates of adherence to HAART, and immunologic changes associated with mental illness itself. We need to improve our design of prevention, screening, and treatment programs to better reach individuals with comorbid HIV and mental illness.

Nonadherence with pediatric human immunodeficiency virus therapy as medical neglect

OBJECTIVE

To examine the results of an interventionist approach applied to human immunodeficiency virus (HIV)-infected children for whom caregiver nonadherence was suspected as the cause of treatment failure.

METHODS

The medical records of a cohort of 16 perinatally HIV-infected children whose care was managed at the Arkansas Children's Hospital Pediatric HIV Clinic for an uninterrupted period of >or=3 years were reviewed through July 2003. Data collected included date of birth, dates of and explanations for clinic visits and hospitalizations, dates of laboratory evaluations, CD4(+) T cell percentages, plasma HIV-1 RNA levels, antiretroviral medications, viral resistance tests (eg, phenotype and genotype), and physician-initiated interventions to enhance adherence to the medication regimen. A stepwise interventionist approach was undertaken when patients continued to demonstrate high viral loads, despite documented viral sensitivity to the medication regimen and caregivers' insistence that medications were being administered regularly. Step 1 was prescribing a home health nurse referral, step 2 was administering directly observed therapy (DOT) while the patient was hospitalized for 4 days, and step 3 was submitting a physician-initiated medical neglect report to the Arkansas Department of Human Services.

RESULTS

The results for 6 patients for whom this stepwise approach was initiated are reported. Home health nurse referrals failed to result in sustained improvements in adherence in all 6 cases. Viral load assays performed before and after DOT provided an objective measure of the effect of adherence, with 12 hospitalizations resulting in a mean +/- SD decrease in HIV RNA levels of 1.09 +/- 0.5 log(10) copies per mL, with a range of 0.6 to 2.1 log(10) copies per mL. Four families responded to DOT hospitalization, and sustained decreases in the respective patients' viral loads were noted. In 2 cases, medical neglect reports were submitted when DOT did not result in improved adherence. These patients were eventually placed in foster care, with subsequent improvements in their viral loads and CD4(+) T cell percentages.

CONCLUSIONS

Nonadherence with antiretroviral therapy can be established on the basis of persistently elevated HIV RNA levels that decrease with DOT. Nonadherence poses a danger to the child that is grave and potentially irreversible. Caregivers should be offered all available resources to help them adhere to a sound treatment plan. In cases of demonstrated inability to provide needed care, it is necessary to consider seeking child protection, even for apparently healthy children.

Predictors of adherence and virologic outcome in HIV-infected patients treated with abacavir- or indinavir-based triple combination HAART also containing lamivudine/zidovudine

OBJECTIVES

To compare dosing convenience and adherence with abacavir (ABC) 300 mg plus a fixed-dose lamivudine 150 mg/zidovudine 300 mg combination tablet (COM) twice daily versus indinavir (IDV) plus COM twice daily in treatment-naïve, HIV-1-infected adults; and to evaluate the association among difficulty taking antiretroviral regimens, adherence, and virologic efficacy.

METHODS

An open-label, randomized, multicenter, international study compared the COM/ABC and IDV/COM regimens with respect to self-reported adherence and regimen convenience over 48 weeks. Logistic regression analysis (LRA) was done on a patient sub-sample from both groups to evaluate predictors of adherence and virologic response at last time-point on randomized therapy (LTORT).

RESULTS

The study population was diverse with respect to ethnicity (38% Asian, 27% Hispanic, 28% white, 3% black, 4% other) and gender (39% women, 61% men). Baseline median HIV-1 RNA was 4.80 log(10) copies/mL and CD4+ cell count was 315 cells/mm(3). Of 329 patients who were randomized and received treatment, 315 (96%) provided adherence data. Significantly more patients in the ABC/COM group than in the IDV/COM group reported > or = 95% adherence to therapy (76 vs 58%, p < 0.001) and no difficulty in taking their regimen (91 vs 61%, p < 0.001). In both groups, the highest probability of HIV-1 RNA < 400 copies/mL occurred when median adherence was > or = 95%. The probability of HIV-1 RNA < 400 copies/mL declined more rapidly in the IDV/COM group as adherence rates decreased. LRA showed that no difficulty taking any of the drugs in the regimen, ABC/COM treatment group, and male gender were independent significant predictors of > or = 95% adherence (p < 0.05). Median adherence and baseline HIV-1 RNA were significant predictors of HIV-1 RNA < 400 copies/mL (p < 0.05).

CONCLUSIONS

Patients reported greater ease of use and superior adherence to ABC/COM than IDV/COM. Patient-reported difficulty taking drugs in a regimen was predictive of reduced adherence, and both of the latter factors were predictive of poorer virologic outcome. Adherence levels of > or = 95% in both treatment groups maximized the probability of patients achieving an HIV-1 RNA < 400 copies/mL.

Modeling the Impact of Modified Directly Observed Antiretroviral Therapy on HIV Suppression and Resistance, Disease Progression, and Death

A simulation model that used Markov assumptions with Monte Carlo uncertainty analysis was evaluated 1500 times at 10,000 iterations. Modified directly observed therapy (MDOT) for human immunodeficiency virus was assumed to improve adherence to therapy to 90% of prescribed doses. The impact of MDOT interventions on modeled biological and clinical outcomes was compared for populations with mean rates of adherence (i.e., the mean percentage of prescribed doses taken by each member of the population who had not discontinued therapy) of 40%, 50%, 60%, and 70%. MDOT reduced the risk of virological failure, development of opportunistic infections, and death, yet increased the risk of drug resistance, for each adherence distribution among persons with detectable plasma virus loads. Over 1500 trials, for a population with 50% adherence to therapy and a 12-month period, MDOT increased the median rate of virological suppression from 13.2% to 37.0% of patients, decreased the rate of opportunistic infection from 5.7% to 4.3% of patients, and decreased the death rate from 2.9% to 2.2% of patients. In the same population, however, MDOT increased the rate of new drug resistance mutations from 1.00 to 1.41 per person during the 12-month period. The impact of MDOT was smaller in populations with higher levels of adherence. MDOT interventions will likely improve clinical outcomes in populations with low levels of adherence but may not be effective at preventing drug resistance in treatment-experienced populations. MDOT may be more effective in preventing drug resistance with potent regimens in treatment-naive patients.

Drug resistance and adherence to HIV/AIDS antiretroviral treatment: against a double standard between the north and the south

Here we review the available evidence on adherence to highly active antiretroviral therapy (HAART) and its relationship with the risk of the dissemination of HIV-resistant viral strains in both developed and developing countries. We argue that referring to these issues of resistance and adherence to withhold or delay access to HAART in developing countries implicitly imposes a double standard of thinking that is unacceptable. Scaling-up access to HAART to succeed in low-resource settings, however, requires the long-term monitoring of adherence as well as the clarification of the complex trade-offs between minimizing the costs of therapeutic regimens and minimizing the risks of non-adherence and resistance.

The impact of adherence on CD4 cell count responses among HIV-infected patients

BACKGROUND

There have been concerns that irreversible immune damage may result if highly active antiretroviral therapy (HAART) is initiated after the CD4 cell count declines to below 350 cells/microL; however, the role of antiretroviral adherence on CD4 cell count responses has not been well evaluated.

METHODS

We evaluated CD4 cell count responses of 1522 antiretroviral-naive patients initiating HAART who were stratified by baseline CD4 cell count (<50, 50-199, and >or=200 cells/microL) and adherence.

RESULTS

Among patients starting HAART with <50 cells/microL, during the fifth 15-week period after the initiation of HAART, absolute CD4 cell counts were 200 cells/microL (interquartile range [IQR]: 130-290) for adherent patients versus 60 cells/microL (IQR: 10-130) for nonadherent patients. Similarly, among patients starting HAART with 50 to 199 cells/microL, during the fifth 15-week period after the initiation of HAART, absolute CD4 cell counts were 300 cells/microL (IQR: 180-390) versus 125 cells/microL (IQR: 40-210) for nonadherent patients. In Cox regression analyses, adherence was the strongest independent predictor of the time to a gain of >or=50 cells/microL from baseline (relative hazard [RH] = 2.88, 95% confidence interval [CI]: 2.46-3.37). Among patients with baseline CD4 cell counts <200 cells/microL, adherence was the strongest independent predictor of the time to a CD4 cell count >200 cells/microL (RH = 4.85, 95% CI: 3.15-7.47).

CONCLUSIONS

These data demonstrate that substantial CD4 gains are possible among highly advanced adherent patients and should contribute to the ongoing debate over the optimal time to initiate HAART.

Predictors of virologic failure and resistance in HIV-infected patients treated with nevirapine- or efavirenz-based antiretroviral therapy

Resistance to nonnucleoside reverse transcriptase inhibitors (NNRTIs) increases with the wider use of this class of antiretroviral therapy. The association between adherence and resistance to NNRTI-based regimens is poorly understood. Predictors of virologic failure and resistance according to a baseline evaluation of nonadherence risk factors were determined in a cohort of 71 human immunodeficiency virus (HIV)-infected patients with early virologic response who received an NNRTI-based regimen. During the median follow-up of 29 months, 20 (28%) of 71 patients experienced virologic failure with an NNRTI-based regimen. Virologic failure was associated with repeated drug holidays (> or =48 h of unplanned drug cessation), depression, younger age, and low adherence to therapy during baseline evaluation. Moreover, repeated drug holidays was the only risk factor for developing a major mutation conferring cross-resistance to the NNRTI class (hazard ratio, 22.5; 95% confidence interval, 2.8-180.3; P<.0001). Patients' previous adherence to therapy and drugs genetic barriers, not only the number of pills or doses involved, should be taken into consideration in the decision to simplify highly active antiretroviral therapy.

Reliability and validity of the SF-36 in HIV-infected homeless and marginally housed individuals

OBJECTIVE

To assess the reliability and validity of the Short-Form 36 (SF-36) health survey as a health status indicator among HIV-infected homeless and marginally housed (HMH) individuals.

METHODS

Between July 1996 and May 2000, a sample of HMH individuals completed interviews that included the SF-36. Responses to the SF-36 were analyzed for missing data, range, internal consistency, and construct validity.

RESULTS

Among 330 individuals interviewed, 83% were male, 43% were African-American, and the median age was 39 years. All internal consistency reliability coefficients exceeded 0.70, all item-scale correlations exceeded 0.40, all items were more strongly correlated with their hypothesized scale than any other scale, and all reliability coefficients exceeded inter-scale correlations for the same scale. Three of four physical health scales were significantly associated with CD4 cell count and HIV viral load. All scales were significantly associated with depression.

DISCUSSION

We found that scales were internally consistent, items correlated to an acceptable degree with their hypothesized scales, items were distinct from other scales, physical scales were associated with CD4 cell count and viral load, and all scales were associated with depression. These analyses provide evidence for the reliability and validity of the SF-36 as a measure of health status in HIV-positive HMH individuals.

Relationship with health care provider and adherence to HIV medications

Suboptimal adherence to antiretroviral medications was reported in a sample of 97 inner-city residents with HIV/AIDS. Most respondents had been seeing the same physician for several years. Those who perceived themselves to be more engaged with their health care provider also reported better treatment adherence. This finding, though, should be viewed with caution since self-reported measures were used. Interventions that target adherence could include patients' perceptions of providers.

Are untimed antiretroviral drug levels useful predictors of adherence behavior?

We examined cross-sectionally the relationship between untimed drug levels and adherence in 83 individuals. Abnormally low untimed antiretroviral drug levels were sensitive in identifying individuals adherent to 60% or less of medication doses over 3 - 5-week period. An abnormally low drug level was associated with a higher viral load. A single abnormally low untimed antiretroviral drug level can identify an individual with very low adherence at high risk of HIV disease progression and death.

Medication adherence in HIV-infected adults: effect of patient age, cognitive status, and substance abuse

OBJECTIVE

To examine the predictors of antiretroviral adherence among HIV-infected adults, with a particular focus on advancing age, neuropsychological dysfunction, and substance abuse.

DESIGN

: Prospective observational design.

METHODS

Participants were 148 HIV-infected adults between the ages of 25 and 69 years, all on a self-administered antiretroviral regimen. Medication adherence was tracked over a one-month period using an electronic monitoring device (medication event monitoring system caps). All participants completed a comprehensive battery of neuropsychological tests as well as a structured psychiatric interview.

RESULTS

The mean adherence rate for the entire cohort was 80.7%, with older patients (> or = 50 years) demonstrating significantly better medication adherence than younger patients (87.5 versus 78.3%). Logistic regression analyses found that older patients were three times more likely to be classified as good adherers (defined as > or = 95% adherent). Neurocognitive impairment conferred a 2.5 times greater risk of poor adherence. Among the older patients, those who were classified as poor adherers performed significantly worse on neuropsychological testing, particularly on measures of executive function and psychomotor speed. Current drug abuse/dependence, but not current alcohol abuse/dependence, was also associated with sub-optimal medication adherence.

CONCLUSION

Although older age is associated with higher rates of antiretroviral adherence, older participants who were cognitively impaired showed disproportionate difficulty in adequately adhering to their medication regimen. As such, efforts to detect neuropsychological dysfunction, particularly among older patients, and a thorough assessment of substance abuse, appear to be essential for the effective treatment of HIV-infected adults.

Estrategias para optimizar la adherencia al tratamiento antirretroviral. Intervenciones en la pauta terapéutica

Within the first few years after the introduction of highly active antiretroviral therapy two facts became evident: the treatment was highly effective and proper compliance was essential to achieve the therapeutic objectives. Recently, the regimens containing these drugs have changed. Complex dosing with a large number of tablets taken three times daily together with dietary restrictions has given way to simpler treatments.The main advances include new formulations and new drugs that allow once-daily dosing, the use of ritonavir to enhance the bioavailability of the protease inhibitors and the coformulation of active ingredients in a single capsule. This review analyzes the impact of these interventions on the therapeutic regimen and it discusses the factors that facilitate and those that hinder optimal adherence to highly active antiviral treatment. Adherence is a complex, multidimensional problem. Simplification of the treatment is an important aspect, but it should be accompanied by other strategies focussed on the patient and the medical team in order to achieve effective long-term antiretroviral therapy in all patients.

[Economic and socio-behavioural issues related to highly active antiretroviral therapies for HIV infection: the contribution of social science research]

This article presents a synthesis of the main topics covered by social science research (SSR) on HIV/AIDS, since the advent of highly active antiretroviral therapies (HAART) in 1996. SSR has shown that 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, and that a dynamic approach to adherence, continuously monitoring the impact of patients' subjective experience with HAART is needed. In relationship with the evolution of HIV infection toward a <<chronic disease>>, SSR has dealt with the impact of HAART on all aspects of patients' daily lives (from employment and professional status to sexuality). It has also emphasised the potential contradictions between the hopes generated by these cost-effective therapeutic advances, on the one hand, and the high social vulnerability of a growing proportion of people living with HIV-AIDS, on the other hand. Finally, SSR suggests recommendations for <<normalising>> AIDS public policies without losing the potential for innovations that the fight against this epidemic has introduced in health care and <<Social Security>> systems, as well as physician-patient's relationships.

Barriers to antiretroviral adherence for patients living with HIV infection and AIDS in Botswana

BACKGROUND

Botswana has the highest rate of HIV infection in the world, estimated at 36% among the population aged 15-49 years. To improve antiretroviral (ARV) treatment delivery, we conducted a cross-sectional study of the social, cultural, and structural determinants of treatment adherence.

METHODS

We used both qualitative and quantitative research methodologies, including questionnaires and interviews with patients receiving ARV treatment and their health care providers to elicit principal barriers to adherence. Patient report and provider estimate of adherence (>/=95% doses) were the primary outcomes.

RESULTS

One hundred nine patients and 60 health care providers were interviewed between January and July 2000; 54% of patients were adherent by self-report, while 56% were adherent by provider assessment. Observed agreement between patients and providers was 68%. Principal barriers to adherence included financial constraints (44%), stigma (15%), travel/migration (10%), and side effects (9%). On the basis of logistic regression, if cost were removed as a barrier, adherence is predicted to increase from 54% to 74%.

CONCLUSIONS

ARV adherence rates in this study were comparable with those seen in developed countries. As elsewhere, health care providers in Botswana were often unable to identify which patients adhere to their ARV regimens. The cost of ARV therapy was the most significant barrier to adherence.

Impact of early versus late adherence to highly active antiretroviral therapy on immuno-virological response: a 3-year follow-up study

OBJECTIVE

To assess the impact of different patterns of adherence to highly active antiretroviral therapy (HAART), in particular, the relative impact of early and late adherence, on long-term immuno-virological response in HIV-infected individuals started on a protease inhibitor-containing regimen.

DESIGN

Clinical, immuno-virological and self-reported adherence data were collected at 4 (M4), 12 (M12), 20 (M20), 28 (M28) and 36 (M36) months after HAART initiation in the French APROCO cohort.

METHODS

A standardized self-administered questionnaire classified patients as non-adherent, moderately or highly adherent at each visit. Stable viral suppression at both M28 to M36, and a CD4 cell increase > 200 between M0 and M36 were used as outcome measures.

RESULTS

Of the 582 patients followed regularly through M36, 360 patients had complete adherence data. Although 59.2% were highly adherent at M4, only 25.8% maintained consistent high adherence throughout the follow-up. High adherence at M4 was independently associated with both stable viral suppression at M28-M36 [OR (95% CI): 2.8 (1.4-5.5)] and a CD4 cell increase > 200 during the same period [OR (95% CI): 3.9 (1.7-9.7)]. However, 'moderately adherent' patients between M12 and M36 had the same likelihood [OR (95% CI): 1.9 (1.1-3.2)] as patients who were always high adherent [OR (95% CI): 1.9 (1.1-3.2)] of achieving stable viral load suppression, relative to those who reported non-adherence episodes.

CONCLUSION

Optimizing adherence in the early months of treatment is crucial to ensure long-term immuno-virological high adherence during follow-up have a less negative impact. Priority should be given to interventions aimed to improve adherence in the early months of HAART.

Projecting the cost-effectiveness of adherence interventions in persons with human immunodeficiency virus infection

PURPOSE

To explore the cost-effectiveness of interventions to improve adherence to combination antiretroviral therapy in patients with human immunodeficiency virus (HIV) infection.

METHODS

A simulation model of HIV infection, incorporating CD4 cell count and HIV ribonucleic acid levels as predictors of disease progression, was used to estimate the lifetime costs and quality-adjusted life expectancy associated with clinical interventions to improve adherence to antiretroviral therapy (e.g., directly observed therapy, automatic medication dispensers, beepers, portable alarms) in a clinical trial cohort with early disease (mean CD4 count, 350 cells/microL), a clinical trial cohort with advanced disease (mean CD4 count, 87 cells/microL), and an urban cohort (mean CD4 count, 217 cells/microL). Data were from clinical trials, national databases, and published literature.

RESULTS

For relatively healthy patients with early disease, interventions that reduced virologic failure rates by 10% increased quality-adjusted life expectancy by 3.2 months, whereas those that reduced failure by 80% increased quality-adjusted life expectancy by 34.8 months, as compared with standard care. The cost-effectiveness ratio was below 50000 US dollars per quality-adjusted life-year (QALY) for interventions costing 100 US dollars per month provided that failure rates were reduced by at least 10%, and for those costing 500 US dollars per month provided that failure rates were reduced by more than 50%. For both patients with advanced disease and those from an urban cohort, adherence interventions costing about 500 US dollars per month (e.g., directly observed therapy) had to reduce failure by about 25% to have cost-effectiveness ratios below 50000 US dollars per QALY.

CONCLUSION

In patients with lower baseline levels of adherence or advanced disease, even very expensive, moderately effective adherence interventions are likely to confer cost-effectiveness benefits that compare favorably with other interventions.

High levels of adherence do not prevent accumulation of HIV drug resistance mutations

OBJECTIVES

To assess the relationship between development of antiretroviral drug resistance and adherence by measured treatment duration, virologic suppression, and the rate of accumulating new drug resistance mutations at different levels of adherence.

METHODS

Adherence was measured with unannounced pill counts performed at the participant's usual place of residence in a prospective cohort of HIV-positive urban poor individuals. Two genotypic resistance tests separated by 6 months (G1 and G2) were obtained in individuals on a stable regimen and with detectable viremia (> 50 copies/ml). The primary resistance outcome was the number of new HIV antiretroviral drug resistance mutations occurring over the 6 months between G1 and G2.

RESULTS

High levels of adherence were closely associated with greater time on treatment (P < 0.0001) and viral suppression (P < 0.0001) in 148 individuals. In a subset of 57 patients with a plasma viral load > 50 copies/ml on stable therapy, the accumulation of new drug resistance mutations was positively associated with the duration of prior treatment (P = 0.03) and pill count adherence (P = 0.002). Assuming fully suppressed individuals (< 50 copies/ml) do not develop resistance, it was estimated that 23% of all drug resistance occurs in the top quintile of adherence (92-100%), and over 50% of all drug resistance mutations occur in the top two quintiles of adherence (79-100%).

CONCLUSION

Increasing rates of viral suppression at high levels of adherence is balanced by increasing rates of drug resistance among viremic patients. Exceptionally high levels of adherence will not prevent population levels of drug resistance.

Stability of adherence to highly active antiretroviral therapy over time among clients enrolled in the treatment adherence demonstration project

Adherence to antiretroviral medications is essential to therapeutic success. Many published studies have investigated the degree of adherence or nonadherence, but sample sizes have generally been small, and adherence has seldom been viewed as a longitudinal process. This paper investigates the stability of adherence over time among HIV-infected individuals attending adherence support programs in New York State. The study cohort consists of 435 clients who were on HAART at baseline and who completed at least 2 follow-up interviews. Although cross-sectional nonadherence did not exceed 35%, nonadherence reached 54% when considered across all 3 interviews. Analysis of transition matricies revealed moderate stability in adherence over time (e.g., first follow-up adherence was 81.0% for clients adherent at baseline, compared with 58.3% for clients nonadherent at baseline). Second-order transition matricies offered additional predictive utility. Multivariate results indicated that, for some, it was the transition from a desirable to an undesirable state (e.g., from no illicit drug use to illicit drug use) that increased the likelihood of nonadherence, rather than the presence of these characteristics over time. Findings illustrate the importance of multiple, periodic assessments of adherence and the need to consider strategies to increase stability in the factors affecting adherence to HAART.

Twenty years of therapy for HIV-1 infection

Antiretroviral therapy, where available, has transformed HIV-1 disease into a treatable and somewhat chronic infection. This article summarizes the accomplishments thus far and what lies ahead in our struggle to improve the treatment of, and possibly eliminate, HIV-1 infection.

Adherence is not a barrier to successful antiretroviral therapy in South Africa

OBJECTIVE

To determine adherence of an indigent African HIV-infected cohort initiating antiretroviral therapy (ART); to identify predictors of incomplete adherence (< 95%) and virologic failure (> 400 HIV RNA copies/ml).

DESIGN

Prospective monitoring of adherence in a poor HIV-positive cohort, attending a public sector hospital and receiving ART through phase III studies.

METHODS

Adherence to ART was determined over 48 weeks by counting tablet-returns. Logistic regression models including age, WHO HIV stage, home language, socio-economic status, complexity and type of regimen were fitted to determine predictors of incomplete adherence and virologic failure at 48 weeks.

RESULTS

289 patients were recruited between January 1996 and May 2001. Median (mean) adherence of the cohort was 93.5% (87.2%). Three times daily dosing [risk ratio (RR), 3.07; 95% confidence interval (CI), 1.40-6.74], speaking English (RR, 0.41; 95% CI, 0.21-0.80) and age (RR, 0.97; 95% CI, 0.94-0.99) were independent predictors of incomplete adherence. Socio-economic status, sex and HIV stage did not predict adherence. Independent predictors of virologic failure included baseline viral load (RR, 2.57; 95% CI, 1.57-4.22) and three times daily dosing (RR, 2.64; 95% CI, 1.23-5.66), incomplete adherence (RR, 1.92; 95% CI, 1.10-3.57), age (RR, 0.96; 95% CI, 0.92-0.99) and dual nucleoside therapy (RR, 2.69; 95% CI, 1.17-6.15).

CONCLUSION

The proportion of individuals achieving viral suppression matched results from the developing world. Speaking the same language as site staff and simplified dosing frequency were beneficial. Socio-economic status had no impact on adherence and should not be used as a limitation to ART access.

Doubts about DOT: antiretroviral therapy for resource-poor countries

INTRODUCTION

Directly observed therapy programs developed for tuberculosis (TB) have been suggested as a model for the provision of HIV medications in resource-poor countries in order to ensure adherence and prevent drug resistance.

METHODS

Opinions were formed based on a review of scientific literature regarding the effectiveness of witnessed dosing in directly observed TB therapy programs, adherence to HIV antiretroviral therapy in resource-rich and resource-poor settings, relationship between adherence and HIV antiretroviral drug resistance, HIV viral load and risk of HIV transmission, and stigmatization concerns related to HIV and TB in resource-poor settings.

RESULTS/CONCLUSIONS

We suggest that the enthusiasm for HIV directly observed therapy programs is premature based on: equivocal evidence that witnessed dosing is superior to self administered therapy; mistaken assumptions that resource-poor countries are a 'special case' with respect to adherence; possible paradoxical impact of good adherence on HIV drug resistance; unproven efficacy of antiretroviral therapy in preventing HIV transmission; and potential stigmatization of daily antiretroviral dosing.

Adherence to highly active antiretroviral therapy is better in patients receiving non-nucleoside reverse transcriptase inhibitor-containing regimens than in those receiving protease inhibitor-containing regimens

The difference between adherence to non- nucleoside reverse transcriptase inhibitor (NNRTI) and protease inhibitor (PI)-based regimens was investigated. Better adherence was found in NNRTI-treated patients, especially when efavirenz was included in the regimen, compared with single PI-treated patients and in those with CD4 cell counts less than 200 x 10(6)/l. By contrast, younger age, self-report of active drug use, fatigue or vomiting negatively affected adherence. Self-reported sexual dysfunction was significantly associated with non-adherence only in PI-treated individuals.

Polypharmacy and medication adherence in patients with type 2 diabetes

OBJECTIVE

To determine medication adherence and predictors of suboptimal adherence in a community cohort of patients with diabetes and to test the hypothesis that adherence decreases with increased number of medicines prescribed.

RESEARCH DESIGN AND METHODS

A total of 128 randomly selected patients with type 2 diabetes from a single community health center responded to a pharmacist-administered questionnaire regarding medication use. Survey data were linked to clinical data available from the electronic medical record. We assessed self-reported adherence rates for each diabetes-related medicine, barriers and attitudes regarding medication use, and HbA(1c), total cholesterol, and blood pressure levels.

RESULTS

Patients were taking a mean of 4.1 (+/-1.9) diabetes-related medicines. The average 7-day adherence was 6.7 +/- 1.1 days. Total number of medicines prescribed was not correlated with medication adherence. Adherence was significantly lower for medicines not felt to be improving current or future health (6.1 vs. 6.9 days out of 7, P < 0.001). Among patients on three or more medicines, 71% (15 of 21 patients) with suboptimal adherence were perfectly adherent with all but one medicine. Side effects were the most commonly reported problem with medication use. Of 29 medicines causing side effects that interfered with adherence, 24 (83%) did so for >1 month, and only 7 (24%) were reported to the patient's primary care physician.

CONCLUSIONS

In this sample, patients reported very high medication adherence rates regardless of number of medicines prescribed. Among patients on multiple medicines, most patients with suboptimal adherence were perfectly adherent to all but one medicine. Unreported side effects and a lack of confidence in immediate or future benefits were significant predictors of suboptimal adherence. Physicians should not feel deterred from prescribing multiple agents in order to achieve adequate control of hyperglycemia, hypertension, and hyperlipidemia.

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.

Human immunodeficiency virus-associated dementia: an evolving disease

This article reviews the changing epidemiology of HIV-associated dementia, current concepts of the different patterns of dementia under the influence of highly active antiretroviral therapy, and reviews therapeutic aspects.

Association of social stress, illicit drug use, and health beliefs with nonadherence to antiretroviral therapy

OBJECTIVE

To assess the roles of socioeconomic status, social stability, social stress, health beliefs, and illicit drug use with nonadherence to antiretroviral therapy.

DESIGN

Cross-sectional study.

SETTING

Urban hospital clinic.

PARTICIPANTS

One hundred ninety-six consecutive HIV-infected patients taking at least 1 antiretroviral medication, awaiting a visit with their primary care provider.

METHODS

Patients were interviewed while waiting for a clinic appointment and were asked to fill out a 4-part survey with questions regarding antiretroviral adherence, illicit drug use, health beliefs, and social situation. Adherence was defined as the percentage of doses taken, i.e., the number of doses taken divided by the number of doses prescribed over a 2-week interval. Univariate and multivariate logistic regressions were performed to identify factors associated with nonadherence in different patient subgroups.

MAIN RESULTS

Nonadherence to antiretroviral therapy was associated with active illicit drug use (adjusted odds ratio [AOR], 2.31; 95% confidence interval [95% CI], 1.17 to 4.58), eating fewer than 2 meals per day (AOR, 3.31; 95% CI, 1.11 to 9.92), and feeling as though pressures outside of the clinic affected patient's ability to take antiretroviral medications as prescribed (AOR, 2.22; 95% CI, 0.99 to 4.97). In patients with a history of injection drug use, nonadherence to antiretroviral therapy was independently associated with eating fewer than 2 meals per day (AOR, 17.54; 95% CI, 1.92 to 160.4) and active illicit drug use (AOR, 4.18; 95% CI, 1.68 to 10.75). In patients without any injection drug use, nonadherence was only associated with feeling as though pressures outside of clinic affected patient's ability to take antiretroviral medications as prescribed (AOR, 3.55; 95% CI, 1.07 to 11.76). Male-to-male sexual contact was associated with lower nonadherence in patients with an HIV risk factor other than injection drug use (AOR, 0.35; 95% CI, 0.13 to 0.95). A history of drug use but no illicit drug use within 6 months of the interview was not associated with an increased rate of nonadherence.

CONCLUSIONS

Although our sample size was limited and variables that are not significant in subgroup analysis may still be associated with adherence, our results suggest that correlates of nonadherence are HIV risk factor specific. Strategies to increase antiretroviral adherence in HIV-infected patients should include social support interventions targeted at different risk factors for different patient groups.

A two-way messaging system to enhance antiretroviral adherence

Failure to adhere to complex antiretroviral regimens can lead to resistance and treatment failure among HIV-positive persons. In this study of the feasibility of an automated two-way messaging system to improve adherence, participants received multiple short daily messages designed to remind, educate, encourage adherence, and solicit responses concerning side effects and self-reported adherence. Twenty-five participants remained in the study for a median of 208 days, receiving 17,440 messages and replying to 14,677 (84%). Participants reported missing one or more doses on 36% of 743 queries and reported medication side effects on 26% of 729 queries. Participants expressed high satisfaction with the messaging system and reported that it helped with medication adherence. The study suggests that it is feasible to use an automated wireless two-way messaging system to communicate with HIV-positive patients over an extended period of time.

Adherence to antiretroviral therapy among patients with HIV: a critical link between behavioral and biomedical sciences

Rapid advances in biomedical science, such as pharmaceutical developments for HIV disease, must be integrated with advances in behavioral science to further our understanding of medication adherence. This article evaluates the current state of the science in adherence to antiretroviral therapy for persons with HIV. The primary objectives are to 1) identify critical determinants of adherence, and 2) describe interventions to improve adherence. Adherence is a complex dynamic behavior influenced by characteristics of the patient, treatment regimen, disease, patient-provider relationship, and clinical setting. Therefore, the most promising interventions are multifaceted and target different locations in this matrix simultaneously. Unfortunately, nonadherence remains a formidable barrier in the management of HIV, resulting in the development of resistance and drug failure. Moreover, adherence is a public health concern, with implications for the transmission of HIV in general and the transmission of drug-resistant strains of HIV specifically. Despite substantial attention to adherence in recent years, much more remains to be done to better understand and promote adherence to antiretroviral therapy through effective interventions. From this integration of biomedical and behavioral science, effective clinical interventions can be developed and implemented to enhance the health of patients with HIV.

Virologic and immunologic response, clinical progression, and highly active antiretroviral therapy adherence

A growing body of evidence suggests that a high degree of adherence is required to achieve and maintain a successful virologic response both in the short and long term. This holds true despite the definition of adherence or how it is measured. Reported differences in the degree of adherence required are likely due to differences in study design, difficulty measuring patient adherence, patient population studied, and the antiretroviral regimen studied. Virologic suppression and immunologic response often go hand in hand, but the impact of adherence on change in CD4 count tends to be delayed and, therefore, less apparent than the impact on HIV viral load. Degree of adherence has also been shown to be associated with AIDS-related morbidity, mortality, and hospitalizations.

Nonadherence among HIV-infected injecting drug users: the impact of social instability

The authors tested the impact of social instability on adherence to highly active antiretroviral therapy (HAART) among patients infected with HIV through injection drug use (IDU; MANIF2000 cohort). In the study, they analyzed sociodemographic baseline characteristics to develop an indicator of social instability. Information concerning adherence to HAART was collected through questionnaires during a 2-year follow-up period. Factors associated with nonadherence were studied in two different groups: 1) patients who had stopped injection drug use (ex-IDUs) and who were not in drug maintenance programs (DMT) during the entire follow-up period, and 2) those who were still opiate dependent. Among the 210 eligible patients, 114 were classified as ex-IDUs and 96 as opiate dependent. Ex-IDUs reported nonadherence behaviors in 96 of 384 visits (25.0%), while opiate-dependent patients were nonadherent in 111 of 308 visits (36.0%; p = .02). Among ex-IDUs, the only factor associated with nonadherence was social instability, while among opiate-dependent patients, injection behavior was the only determinant of nonadherence behavior. For opiate-dependent patients, DMT may enhance adherence to HAART, but only if it is successful in reducing abuse of injection practices. For ex-IDUs, it is very important that the management of social difficulties be taken into account to increase adherence to HAART.

Computer-assisted self-interviewing (CASI) to improve provider assessment of adherence in routine clinical practice

Adherence to HIV antiretroviral therapy is closely associated with viral load suppression, progression to AIDS, and death in HIV-infected people. There is, however, no standardized approach to adherence assessment in routine clinical practice, and several studies suggest that providers rarely estimate adherence better than chance. Computer-assisted self-interview technology is an efficient means to identify HIV antiretroviral regimen errors and monitor adherence in order to maximize the benefits of therapy.

Initial therapy of HIV infection

BACKGROUND

The use of antiretroviral therapy has improved the quality of life and has increased the survival of HIV-infected individuals. However, the rapid rate of virus mutation and subsequent emergence of drug-resistant HIV variants threaten the longer-term efficacy of HIV treatment. The initial regimen provides the greatest chance for lasting suppression of viral load.

AIMS

Appropriate selection of the initial antiretroviral regimen is critical. The growing number of drug classes allows healthcare providers to individualize treatment regimens. Factors influencing the selection of first-line therapy include baseline viral load and CD4 count, drug pharmacokinetics, potency, tolerability, safety, resistance and salvageability. Characteristics likely to affect adherence, such as regimen complexity and pill burden, must also be considered, as poor adherence is the most common cause of treatment failure.

CONCLUSION

The selection of the initial regimen requires consideration of several factors. Drugs from new classes as well as new drugs from existing classes with favorable resistance and side effect profiles are in various stages of development. Many of these drugs will enhance available options for initial therapy.