The costs of HIV antiretroviral therapy adherence programs and impact on health care utilization

Cost-effectiveness of the long-acting regimen cabotegravir plus rilpivirine for the treatment of HIV-1 and its potential impact on adherence and viral transmission: A modelling study

Introduction

Combination antiretroviral therapy (cART) improves outcomes for people living with HIV (PLWH) but requires adherence to daily dosing. Suboptimal adherence results in reduced treatment effectiveness, increased costs, and greater risk of resistance and onwards transmission. Treatment with long-acting (LA), injection-based ART administered by healthcare professionals (directly observed therapy (DOT)) eliminates the need for adherence to daily dosing and may improve clinical outcomes. This study reports the cost-effectiveness of the cabotegravir plus rilpivirine LA regimen (CAB+RPV LA) and models the potential impact of LA DOT therapies.

Methods

Parameterisation was performed using pooled data from recent CAB+RPV LA Phase III trials. The analysis was conducted using a cohort-level hybrid decision-tree and state-transition model, with states defined by viral load and CD4 cell count. The efficacy of oral cART was adjusted to reflect adherence to daily regimens from published data. A Canadian health service perspective was adopted.

Results

CAB+RPV LA is predicted to be the dominant intervention when compared to oral cART, generating, per 1,000 patients treated, lifetime cost-savings of $1.5 million, QALY and life-year gains of 107 and 138 respectively with three new HIV cases averted.

Conclusions

Economic evaluations of LA DOTs need to account for the impact of adherence and HIV transmission. This study adds to the existing literature by incorporating transmission and using clinical data from the first LA DOT regimen. Providing PLWH and healthcare providers with novel modes of ART administration, enhancing individualisation of treatment, may facilitate the achievement of UNAIDS 95-95-95 objectives.

Enhancing value and lowering costs of care: a qualitative exploration of a randomized linkage to care intervention in South Africa

While interventions to improve HIV linkage and retention in care exist, none have demonstrated results sufficient to reach UNAIDS 90-90-90 goals. We explored values and costs of seeking clinical care through testing three strategies to improve linkage to care: Point of care CD4 testing alone (POC-CD4), POC-CD4 combined with transportation support and combined with care facilitation. We conducted in-depth interviews with participants and transcribed audio-recordings of care facilitation sessions. Participants described values and costs enhanced or addressed by the three interventions. Psychosocial support provided through the care facilitation intervention appeared salient. Participants named other values and costs of seeking care unrelated to the intervention, such as encouragement from healthcare workers and aversion to lifelong treatment. Combined with the quantitative results of this trial, these findings may point to why the care facilitation arm was successful but not the POC-CD4 only or transportation arms. It also provides guidance for future interventions.

From Theory to Practice: Implementation of a Resource Allocation Model in Health Departments

OBJECTIVE

To develop a resource allocation model to optimize health departments' Centers for Disease Control and Prevention (CDC)-funded HIV prevention budgets to prevent the most new cases of HIV infection and to evaluate the model's implementation in 4 health departments.

DESIGN, SETTINGS, AND PARTICIPANTS

We developed a linear programming model combined with a Bernoulli process model that allocated a fixed budget among HIV prevention interventions and risk subpopulations to maximize the number of new infections prevented. The model, which required epidemiologic, behavioral, budgetary, and programmatic data, was implemented in health departments in Philadelphia, Chicago, Alabama, and Nebraska.

MAIN OUTCOME MEASURES

The optimal allocation of funds, the site-specific cost per case of HIV infection prevented rankings by intervention, and the expected number of HIV cases prevented.

RESULTS

The model suggested allocating funds to HIV testing and continuum-of-care interventions in all 4 health departments. The most cost-effective intervention for all sites was HIV testing in nonclinical settings for men who have sex with men, and the least cost-effective interventions were behavioral interventions for HIV-negative persons. The pilot sites required 3 to 4 months of technical assistance to develop data inputs and generate and interpret the results. Although the sites found the model easy to use in providing quantitative evidence for allocating HIV prevention resources, they criticized the exclusion of structural interventions and the use of the model to allocate only CDC funds.

CONCLUSIONS

Resource allocation models have the potential to improve the allocation of limited HIV prevention resources and can be used as a decision-making guide for state and local health departments. Using such models may require substantial staff time and technical assistance. These model results emphasize the allocation of CDC funds toward testing and continuum-of-care interventions and populations at highest risk of HIV transmission.

Pilot RCT of bidirectional text messaging for ART adherence among nonurban substance users with HIV

OBJECTIVE

This pilot study tested the preliminary efficacy of a theory-based bidirectional text messaging intervention (TEXT) on antiretroviral (ART) adherence, missed care visits, and substance use among people with HIV.

METHOD

Participants with recent substance use and ART nonadherence from 2 nonurban HIV clinics were randomized to TEXT or to usual care (UC). The TEXT intervention included daily queries of ART adherence, mood, and substance use. The system sent contingent intervention messages created by participants for reports of adherence/nonadherence, good mood/poor mood, and no substance use/use. Assessments were at preintervention, postintervention, and 3-month postintervention follow-up. Objective primary outcomes were adherence, measured by past 3-month pharmacy refill rate, and proportion of missed visits (PMV), measured by medical records. The rate of substance-using days from the timeline follow-back was a secondary outcome.

RESULTS

Sixty-three patients participated, with 33 randomized to TEXT and 30 to UC. At preintervention, adherence was 64.0%, PMV was 26.9%, and proportion of days using substances was 53.0%. At postintervention, adherence in the TEXT condition improved from 66% to 85%, compared with 62% to 71% in UC participants (p = .04). PMV improved from 23% to 9% for TEXT participants and 31% to 28% in UC participants (p = .12). There were no significant differences between conditions in substance-using days at postintervention. At 3-month follow-up, differences were not significant.

CONCLUSIONS

Personalized bidirectional text messaging improved adherence and shows promise to improve visit attendance, but did not reduce substance using days. This intervention merits further testing and may be cost-efficient given its automation.

Examining geographic and socio-economic differences in outpatient and inpatient consumer expenditures for treating HIV/AIDS in Nigeria

INTRODUCTION

The expenditures on treatment of HIV/AIDS to households were examined to quantify the magnitude of the economic burden of HIV/AIDS to different population groups in Nigeria. The information will also provide a basis for increased action towards a reduction of the economic burden on many households when accessing antiretroviral therapy (ART).

METHODS

A household survey was administered in three states, Adamawa, Akwa Ibom and Anambra, from the South-East, North-East and South-South zones of Nigeria, respectively. A pretested interviewer-administered questionnaire was used to collect data from a minimum sample of 1200 people living with HIV/AIDS (PLHIV). Data were collected on the medical and non-medical expenditures that patients incurred to treat HIV/AIDS for their last treatment episode within three months of the interview date. The expenditures were for outpatient visits (OPV) and inpatient stays (IPS). The incidence of catastrophic health expenditure (CHE) on ART treatment services was computed for OPV and IPS. Data were disaggregated by socio-economic status (SES) and geographic location of the households.

RESULTS

The average OPV expenditures incurred by patients per OPV for HIV/AIDS treatment was US$6.1 with variations across SES and urban-rural residence. More than 95% of the surveyed households spent money on transportation to a treatment facility and over 70% spent money on food for OPV. For medical expenditures, the urbanites paid more than rural dwellers. Many patients incurred CHE during outpatient and inpatient visits. Compared to urban dwellers, rural dwellers incurred more CHE for outpatient (p=0.02) and inpatient visits (p=0.002).

CONCLUSIONS

Treatment expenditures were quite high, inequitable and catastrophic in some instances, hence further jeopardizing the welfare of the households and the PLHIV. Strategically locating fully functional treatment centres to make them more accessible to PLHIV will largely reduce expenditures for travel and the need for food during visits. Additionally, financial risk-protection mechanisms such as treatment vouchers, reimbursement and health insurance that will significantly reduce the expenditures borne by PLHIV and their households in seeking ART should be implemented.

The Epidemiologic and Economic Impact of Improving HIV Testing, Linkage, and Retention in Care in the United States

BACKGROUND

Recent guidelines advocate early antiretroviral therapy (ART) to decrease human immunodeficiency virus (HIV) morbidity and prevent transmission, but suboptimal engagement in care may compromise impact. We sought to determine the economic and epidemiologic impact of incomplete engagement in HIV care in the United States.

METHODS

We constructed a dynamic transmission model of HIV among US adults (aged 15-65 years) and conducted a cost-effectiveness analysis of improvements along the HIV care continuum : We evaluated enhanced HIV testing (annual for high-risk groups), increased 3-month linkage to care (to 90%), and improved retention (50% relative reduction in yearly disengagement and 50% increase in reengagement). Our primary outcomes were HIV incidence, mortality, costs and quality-adjusted life-years (QALYs).

RESULTS

Despite early ART initiation, a projected 1.39 million (95% uncertainty range [UR], 0.91-2.2 million) new HIV infections will occur at a (discounted) cost of $256 billion ($199-298 billion) over 2 decades at existing levels of HIV care engagement. Enhanced testing with increased linkage has modest epidemiologic benefits and could reduce incident HIV infections by 21% (95% UR, 13%-26%) at a cost of $65 700 per QALY gained ($44 500-111 000). By contrast, comprehensive improvements that couples enhanced testing and linkage with improved retention would reduce HIV incidence by 54% (95% UR, 37%-68%) and mortality rate by 64% (46%-78%), at a cost-effectiveness ratio of $45 300 per QALY gained ($27 800-72 300).

CONCLUSIONS

Failure to improve engagement in HIV care in the United States leads to excess infections, treatment costs, and deaths. Interventions that improve not just HIV screening but also retention in care are needed to optimize epidemiologic impact and cost-effectiveness.

Cost-Effectiveness of Improving Health Care to People with HIV in Nicaragua

Background. A 2010 evaluation found generally poor outcomes among HIV patients on antiretroviral therapy in Nicaragua. We evaluated an intervention to improve HIV nursing services in hospital outpatient departments to improve patient treatment and retention in care. The intervention included improving patient tracking, extending clinic hours, caring for children of HIV+ mothers, ensuring medication availability, promoting self-help groups and family involvement, and coordinating multidisciplinary care. Methods. This pre/postintervention study examined opportunistic infections and clinical status of HIV patients before and after implementation of changes to the system of nursing care. Hospital expenditure data were collected by auditors and hospital teams tracked intervention expenses. Decision tree analysis determined incremental cost-effectiveness from the implementers' perspective. Results. Opportunistic infections decreased by 24% (95% CI: 14%-34%) and 11.3% of patients improved in CDC clinical stage. Average per-patient costs decreased by $133/patient/year (95% CI: $29-$249). The intervention, compared to business-as-usual strategy, saved money while improving outcomes. Conclusions. Improved efficiency of services can allow more ART-eligible patients to receive therapy. We recommended the intervention be implemented in all HIV service facilities in Nicaragua.

A qualitative study of underutilization of the AIDS drug assistance program

In our previous work, we demonstrated underutilization of the AIDS Drug Assistance Program (ADAP) at an HIV clinic in Alabama. In order to understand barriers and facilitators to utilization of ADAP, we conducted focus groups of ADAP enrollees. Focus groups were stratified by sex, race, and historical medication possession ratio as a measure of program utilization. We grouped factors according to the social-ecological model. We found that multiple levels of influence, including patient and clinic-related factors, influenced utilization of antiretroviral medications. Patients introduced issues that illustrated high-priority needs for ADAP policy and implementation, suggesting that in order to improve ADAP utilization, the following issues must be addressed: patient transportation, ADAP medication refill schedules and procedures, mailing of medications, and the ADAP recertification process. These findings can inform a strategy of approaches to improve ADAP utilization, which may have widespread implications for ADAP programs across the United States.

Costs and cost-effectiveness of HIV community services: quantity and quality of studies published 1986-2011

Community services comprise an important part of a country's HIV response. English language cost and cost-effectiveness studies of HIV community services published between 1986 and 2011 were reviewed but only 74 suitable studies were identified, 66% of which were performed in five countries. Mean study scores by continent varied from 42 to 69% of the maximum score, reflecting variation in topics covered and the quality of coverage: 38% of studies covered key and 11% other vulnerable populations - a country's response is most effective and efficient if these populations are identified given they are key to a successful response. Unit costs were estimated using different costing methods and outcomes. Community services will need to routinely collect and analyze information on their use, cost, outcome and impact using standardized costing methods and outcomes. Cost estimates need to be disaggregated into relevant cost items and stratified by severity and existing comorbidities. Expenditure tracking and costing of services are complementary aspects of the health sector 'resource cycle' that feed into a country's investment framework and the development and implementation of national strategic plans.

Cost effectiveness of a computer-delivered intervention to improve HIV medication adherence

BACKGROUND

High levels of adherence to medications for HIV infection are essential for optimal clinical outcomes and to reduce viral transmission, but many patients do not achieve required levels. Clinician-delivered interventions can improve patients' adherence, but usually require substantial effort by trained individuals and may not be widely available. Computer-delivered interventions can address this problem by reducing required staff time for delivery and by making the interventions widely available via the Internet. We previously developed a computer-delivered intervention designed to improve patients' level of health literacy as a strategy to improve their HIV medication adherence. The intervention was shown to increase patients' adherence, but it was not clear that the benefits resulting from the increase in adherence could justify the costs of developing and deploying the intervention. The purpose of this study was to evaluate the relation of development and deployment costs to the effectiveness of the intervention.

METHODS

Costs of intervention development were drawn from accounting reports for the grant under which its development was supported, adjusted for costs primarily resulting from the project's research purpose. Effectiveness of the intervention was drawn from results of the parent study. The relation of the intervention's effects to changes in health status, expressed as utilities, was also evaluated in order to assess the net cost of the intervention in terms of quality adjusted life years (QALYs). Sensitivity analyses evaluated ranges of possible intervention effectiveness and durations of its effects, and costs were evaluated over several deployment scenarios.

RESULTS

The intervention's cost effectiveness depends largely on the number of persons using it and the duration of its effectiveness. Even with modest effects for a small number of patients the intervention was associated with net cost savings in some scenarios and for durations greater than three months and longer it was usually associated with a favorable cost per QALY. For intermediate and larger assumed effects and longer durations of intervention effectiveness, the intervention was associated with net cost savings.

CONCLUSIONS

Computer-delivered adherence interventions may be a cost-effective strategy to improve adherence in persons treated for HIV.

TRIAL REGISTRATION

Clinicaltrials.gov identifier NCT01304186.

Targeting candidates for directly administered highly active antiretroviral therapy: benefits observed in HIV-infected injecting drug users in residential drug-rehabilitation facilities

The purpose of this study was to evaluate retrospectively the potential benefits of directly administered antiretroviral therapy (DAART) in HIV-infected former injecting drug users (ex-IDUs) admitted to residential drug rehabilitation facilities. We compared 106 of these patients consecutively admitted in 12 communities where DAART was administered (DAART group) to two matched control groups of ex-IDUs undergoing self-administered ART: 106 subjects in other 10 communities (SAT group) and 106 outpatients at hospital infectious-disease wards where community patients were referred after discharge (OUT group). We estimated the proportion of patients with high adherence and the hazard ratio (HR) of 20% or more increase in the CD4(+) cell count and of reaching an undetectable viral load. The proportion of patients with high adherence to treatment was highest in the DAART group. The probability of 20% or more increase in the CD4(+) cell count was significantly lower in the two control groups versus the DAART group (SAT group HR=0.32; OUT group HR=0.43). The HR of observing an undetectable HIV-RNA level versus DAART was significantly lower in the OUT group (HR: 0.71; 95% confidence interval [CI]: 0.52-0.97) but did not reach statistical significance for the SAT group (HR: 0.99; 95% CI: 0.74-1.33). Our findings after a 24-month follow-up, suggest that DAART in HIV-infected patients of drug-rehabilitation communities improves adherence, immunologic, and virologic outcome toward free outpatients. Even if our retrospective 36-month data do not show a prolonged viral suppression in these patients, DAART may be considered a valuable therapeutic and educational strategy in this particular target group.

Modelling the budget impact of darunavir in the treatment of highly treatment-experienced, HIV-infected adults in France

BACKGROUND

A key element for payers in the assessment of the economic profile of a medication is its anticipated impact on the evolution of healthcare budgets.

OBJECTIVES

To forecast the impact of the use of darunavir with low-dose ritonavir 600/100 mg twice a day (bid) in highly treatment-experienced, HIV-infected adults who have failed one or more protease inhibitor (PI)-containing regimen on the budget of the French Sickness Fund (French healthcare system) over a 3-year time horizon.

METHODS

A transition state model based on disease severity was developed that compared the evolution of antiretroviral and non-antiretroviral-related direct costs of care in the target population over 3 years (2007-2009) under two scenarios: (1) darunavir enters the French market in year 1; (2) darunavir is not available to the target population during 2007-2009. Model inputs were derived from a targeted analysis of the French hospital database in HIV, the darunavir POWER 1 and 2 trials and other relevant clinical studies.

RESULTS

In the scenario where darunavir was available from year 1, the proportion of patients in the lower, more costly CD4 cell count strata (≤ 100 cells per mm³) was consistently lower than in the scenario without darunavir in each year of the model (17.0% vs 19.2%, 13.9% vs 18.3% and 10.8% vs 16.8% for years 1, 2 and 3, respectively). As a result, over the entire 3-year period, the net increase of antiretroviral drug costs (+ 5.6 million Euros; €), resulting from the substitution of older, cheaper PIs by darunavir, is expected to be fully compensated by savings in hospitalization costs (€-9.7 million) and expenditures for other HIV-related (non-antiretroviral) medications (€-7.3 million), leading to a net saving of €11.4 million or 2.9% of the total budget in the scenario without darunavir. Various sensitivity analyses confirmed these projected savings.

CONCLUSION

The use of darunavir/ritonavir (DRV/r) 600/100 mg bid, in combination with other antiretroviral agents, in highly pre-treated, HIV-infected adults who have failed one or more PI-containing highly active antiretroviral therapy regimen is not expected to increase the budget of the French healthcare system, in comparison with a scenario without darunavir. Further research is needed to estimate the budget impact of the use of DRV/r in less treatment-experienced, HIV-infected individuals in France.

Piloting a peer-driven intervention model to increase access and adherence to antiretroviral therapy and HIV care among street-entrenched HIV-positive women in Vancouver

A peer-driven intervention (PDI) was developed to support uptake and adherence to highly active antiretroviral therapy (HAART) among women sex workers who use illicit substances in Vancouver, because uptake and adherence continues to be suboptimal. Trends of adherence were examined among women in this program by (1) exposure to the intervention and (2) risk behaviors including drug use and unstable housing. Between January 2007 and January 2008, 20 HIV-positive women were enrolled into the PDI on a rolling basis. PDI participation included weekly peer support meetings, a health advocate (buddy) system, peer outreach service, and onsite nursing care. Adherence was measured directly with pharmacy records (PR) and indirectly with self-report and viral load (VL) outcomes. Participants attended an average of 50 (21-70) PDI meetings. Overall self-reported adherence was high (92%) and most women (11) reported increased adherence from the first to the last 13 PDI meetings attended (average increase = 18%). The number of viral load tests <or=50 copies/mL increased by 40% from the pre-PDI period (1 year before enrollment), to the PDI period (duration enrolled). PR adherence and improvements in VL outcomes were higher among participants with greater housing instability and frequency of injecting/smoking drugs. Despite a very difficult environment to provide HIV care, there is evidence to suggest that the PDI may have had a positive impact on adherence outcomes. Although this would not predict long-term treatment success, the PDI approach to HIV treatment support is a promising program for women who might otherwise be excluded from treatment altogether.

Utilization of medical treatments and adherence to antiretroviral therapy among HIV-positive adults with histories of childhood sexual abuse

HIV is a chronic, life-threatening illness that necessitates regular and consistent medical care. Childhood sexual abuse (CSA) is a common experience among HIV-positive adults and may interfere with treatment utilization. This study examined rates and correlates of treatment utilization among HIV-positive adults with CSA enrolled in a coping intervention trial in New York City. The baseline assessment included measures of treatment utilization, mental health, substance abuse, and other psychosocial factors. In 2002-2004, participants (50% female, 69% African-American, M = 42.3 +/- 6.8 years old) were recruited. Nearly all (99%) received HIV medical care. However, 20% had no outpatient visits and 24% sought emergency services in the past 4 months. Among 184 participants receiving antiretroviral therapy (ART), 22% were less than 90% adherent in the past week. In a multivariable logistic regression model, no outpatient treatment was associated with African American race (AOR = 3.46 [1.42-8.40]), poor social support (AOR = 1.59 [1.03-2.45]), and abstinence from illicit drug use (AOR = 0.37 [0.16-0.85]). Emergency service utilization was associated with HIV symptoms (AOR = 2.30 [1.22-4.35]), binge drinking (AOR=2.92 (1.18-7.24)), and illicit drug use (AOR = 1.98 [1.02-3.85]). Poor medication adherence was associated with trauma symptoms (AOR = 2.64 [1.07-6.75]) and poor social support (AOR = 1.82 [1.09-2.97]). In sum, while participants had access to HIV medical care, a sizable minority did not adhere to recommended guidelines and thus may not be benefiting optimally from treatment. Interventions targeting HIV-positive adults with CSA histories may need to address trauma symptoms, substance abuse, and poor social support that interfere with medical treatment utilization and adherence.

The association of adherence to antiretroviral therapy with healthcare utilization and costs for medical care

BACKGROUND

The association between antiretroviral adherence, healthcare utilization and medical costs has not been well studied.

OBJECTIVE

To examine the relationship of adherence to antiretroviral medications to healthcare utilization and healthcare costs.

METHODS

A retrospective cohort study was conducted using data from 325 previously antiretroviral medication-naive HIV-infected individuals initiating first antiretroviral therapy from 1997 through 2003. The setting was an inner-city safety net hospital and HIV clinic in the US. Adherence was assessed using pharmacy refill data. The average wholesale price was used for prescription costs. Healthcare utilization data and medical costs were obtained from the hospital billing database, and differences according to quartile of adherence were compared using analysis of variance (ANOVA). Multivariate logistic regression was used to assess predictors of higher annual medical costs. Sensitivity analyses were used to examine alternative antiretroviral pricing schemes. The perspective was that of the healthcare provider, and costs were in year 2005 values.

RESULTS

In 325 patients followed for a mean (+/- SD) 3.2 (1.9) years, better adherence was associated with lower healthcare utilization but higher total medical costs. Annual non-antiretroviral medical costs were $US 7,612 in the highest adherence quartile versus $US 10,190 in the lowest adherence quartile. However, antiretroviral costs were significantly higher in the highest adherence quartile ($US 17,513 vs $US 8,690), and therefore the total annual medical costs were also significantly higher in the highest versus lowest adherence quartile ($US 25,125 vs $US 18,880). In multivariate analysis, for every 10% increase in adherence, the odds of having annual medical costs in the highest versus lowest quartile increased by 87% (odds ratio 1.87; 95% CI 1.45, 2.40). In sensitivity analyses, very low antiretroviral prices (as seen in resource-limited settings) inverted this relationship - excellent adherence was cost saving.

CONCLUSION

Better adherence to antiretroviral medication was associated with decreased healthcare utilization and associated costs; however, because of the high cost of antiretroviral therapy, total medical costs were increased. Combination antiretroviral therapy is known to be cost effective; lower antiretroviral costs may make it cost saving as well.