The impact of disease stage on direct medical costs of HIV management: a review of the international literature

Research trends in contemporary health economics: a scientometric analysis on collective content of specialty journals

INTRODUCTION

Health economics is a thriving sub-discipline of economics. Applied health economics research is considered essential in the health care sector and is used extensively by public policy makers. For scholars, it is important to understand the history and status of health economics-when it emerged, the rate of research output, trending topics, and its temporal evolution-to ensure clarity and direction when formulating research questions.

METHODS

Nearly 13,000 articles were analysed, which were found in the collective publications of the ten most specialised health economic journals. We explored this literature using patterns of term co-occurrence and document co-citation.

RESULTS

The research output in this field is growing exponentially. Five main research divisions were identified: (i) macroeconomic evaluation, (ii) microeconomic evaluation, (iii) measurement and valuation of outcomes, (iv) monitoring mechanisms (evaluation), and (v) guidance and appraisal. Document co-citation analysis revealed eighteen major research streams and identified variation in the magnitude of activities in each of the streams. A recent emergence of research activities in health economics was seen in the Medicaid Expansion stream. Established research streams that continue to show high levels of activity include Child Health, Health-related Quality of Life (HRQoL) and Cost-effectiveness. Conversely, Patient Preference, Health Care Expenditure and Economic Evaluation are now past their peak of activity in specialised health economic journals. Analysis also identified several streams that emerged in the past but are no longer active.

CONCLUSIONS

Health economics is a growing field, yet there is minimal evidence of creation of new research trends. Over the past 10 years, the average rate of annual increase in internationally collaborated publications is almost double that of domestic collaborations (8.4% vs 4.9%), but most of the top scholarly collaborations remain between six countries only.

Targeted HIV screening in the emergency department

Despite considerable improvement in human immunodeficiency virus (HIV) knowledge and treatment in the last 3 decades, the overall number of people living with HIV (PLHIV) is still rising with up to one quarter being unaware of their HIV status. Early HIV diagnosis and treatment prolongs life, reduces transmission, improves quality of life, and is a cost-effective public health intervention. The emergency department (ED) sees a large number of patients from marginalized and traditionally underserved populations in whom HIV is known to be more prevalent and who may not attend traditional services because of either cultural reasons or because of a chaotic lifestyle. This article discusses the two main approaches to screening; 'Opt-out' screening offers testing routinely in all clinical settings, and 'Targeted' screening offers testing to individuals presenting with indicator conditions. There are many studies of 'Opt-out' ED HIV screening in urban areas of high-HIV prevalence. However, little is known about the effectiveness of 'targeted' HIV screening, especially in areas of low prevalence. This review discusses the background to HIV screening in the ED and reviews the evidence around 'targeted' HIV screening in adult EDs in different HIV prevalence settings, concluding that targeted HIV screening at the ED can be impactful, cost-effective, and well accepted in the ED population, but its long-term implementation requires extra funding and increased staffing resource limiting its application in low resource setting. Despite most evidence being from areas of high-HIV prevalence, targeted screening might also be appropriate in low-HIV prevalence areas.

The Role of Targeted HIV Screening in the Emergency Department: A Scoping Review

BACKGROUND

Human immunodeficiency virus (HIV) infection continues to expand worldwide, and a significant proportion of infection is still undiagnosed. Recent studies have addressed the impact and feasibility of 'opt-out' HIV screening in Emergency Departments (EDs) in urban settings at high HIV prevalence, whereas little is known about the yield of implementing 'targeted' HIV testing, especially in low-prevalence areas.

OBJECTIVE

The present study undertakes a scoping review of research carried out on the implementation of targeted HIV screening of adult in EDs to determine the impact, feasibility and acceptability of HIV testing in different HIV prevalence settings.

DESIGN

Online databases (EMBASE, MEDLINE) were used to identify papers published between 2000 to 2020. A three-concept search was employed with HIV (HIV, Human immunodeficiency virus infection, HIV infections), targeted testing (Target, screening or testing) and emergency medicine (Emergency Service, emergency ward, A&E, accident and emergency or Emergency Department) (28^th February 2020). Only full-text articles written in English, French, Spanish or Italian and using impact and/or feasibility and/or acceptability of the program as primary or secondary outcomes were analysed.

RESULTS

The search provided 416 articles. Of these, 12 met inclusion criteria and were included in the final review. Most of the included studies were carried out in the United States (n=8; 67%) and in areas of high HIV prevalence (n=11; 92%). Three (20%) were randomized control studies. While the rate of newly diagnosed HIV cases varied widely (0.03-2.2%), likely due to methodological heterogeneity between studies, the linkage of new HIV diagnosis was often high (80-100%) and median CD4+ cell count was always greater than 200 cells per microliter. Targeted HIV screening was found to be cost-effective (out of 2 studies) and well accepted by participants (out 2 studies).

CONCLUSIONS

Targeted HIV screening at the ED can be impactful, feasible and well accepted, but often requires extra funding and staff. Most previous work has focused on areas of high disease prevalence.

Combined estimation of disease progression and retention on antiretroviral therapy among treated individuals with HIV in the USA: a modelling study

BACKGROUND

Accurately estimating HIV disease progression and retention on antiretroviral therapy (ART) can help inform interventions to control HIV microepidemics and mathematical models used to inform health-resource allocation decisions. Our objective was to estimate the monthly probabilities of on-ART CD4 T-cell count progression, mortality, ART dropout, and ART reinitiation using a continuous-time multistate Markov model. We also aimed to validate health-state transition probability estimates to ensure they accurately reproduced the regional HIV microepidemics across the USA.

METHODS

In our modelling study, we considered a cohort of patients from the HIV Research Network, a consortium of 17 adult and paediatric HIV-care providers located in the northeastern (n=8), southern (n=5), and western (n=4) regions of the USA. Individuals aged 15 years or older who were in HIV care (defined as one CD4 test and one HIV-care visit in a calendar year period) with at least one ART prescription between Jan 1, 2010, and Dec 31, 2015, were included in the analysis. We used continuous-time multistate Markov models to estimate transitions between CD4 strata and between on-ART and off-ART states. We examined and adjusted for differences in probability of transition by region, race or ethnicity, sex, HIV risk group, and other baseline clinical indicators.

FINDINGS

The median age of the 32 242 individuals included in the analysis was 44 years (interquartile range 35-51). Over a median follow-up of 4·9 years (2·6-6·0), 8614 (26·7%) of 32 242 people interrupted ART and 1325 (4·1%) of 32 242 people died. Women, men who have sex with men, and individuals with no previous ART experience had greater increases in CD4 cell counts, whereas black people and people who inject drugs had increased probabilities of ART dropout and faster disease progression. Regardless of CD4 strata, individuals had increased hazard for ART dropout if they were from the south (adjusted hazard ratio [aHR] range from 1·91, 95% CI 1·71-2·13, to 2·45, 2·29-2·62) or the west (aHR range from 1·29, 1·10-1·51, to 1·66, 1·51-1·82) of the USA, compared with individuals from the northeast USA.

INTERPRETATION

Our results show heterogeneities in disease progression during ART and probability of ART retention across race and ethnicity, HIV risk groups, and regions. These differences should be viewed as targets for intervention and should be incorporated in mathematical models of regional HIV microepidemics in the USA.

FUNDING

US National Institutes of Health, Agency for Healthcare Research and Quality, and Health Resources and Services Administration.

The cost of hospital care for HIV patients in Colombia: an insurer's perspective

The aim of this study was to evaluate the cost derived from the hospitalization of people living with HIV (PLHIV) in Colombia between 2011 and 2015. This is an analysis of the direct cost of PLHIV hospitalization from the perspective of an insurer of the Colombian General Social Security System. The costs were calculated in Colombian pesos and corrected for inflation on the basis of the 2017 Consumer Price Index of the Bank of the Republic of Colombia. It was converted to US dollars at the Market Representative Exchange Rate of the same year. We analyzed 1129 hospitalizations in 612 PLHIV, of which 12% started with a diagnosis of HIV during the same hospitalization, with the majority in the AIDS stage (63%). The median overall cost of hospitalizations was US$1509 (25th and 75th percentiles: US$711-US$3254), being even higher in patients with AIDS and as the CD4 T lymphocyte count decreased. The cost derived from the medical care of PLHIV increases as the clinical control of the disease worsens, and it is a key indicator of the impact of the strategies implemented for the timely identification of the infection and subsequent management of the disease.

How has the cost of antiretroviral therapy changed over the years? A database analysis in Italy

Background

The number of human immunodeficiency virus (HIV)-related hospitalizations has decreased worldwide in recent years, due to the availability of combined antiretroviral therapies (cART). The present analysis aimed to analyse the economic, and clinical burden of HIV management, after the introduction of systematic use of cART.

Methods

Data from HIV-infected patients, treated at Policlinico San Martino Hospital in Genova (Italy) were retrospectively collected. A comparison between years 2009 and 2015 was performed. HIV-related admissions were identified by using the Diagnosis-Related Group (DRG) codes. The resource consumption of outpatient services was derived by using a modelling approach. Expenditure for drugs was also analysed, as aggregate data.

Results

The number of HIV-infected patients was 898 in 2009 and 1006 in 2015. Overall, the virological success rate improved from 2009 to 2015, as the percentage of patients with HIV-RNA < 50 copies/mL increased from 79 to 89% (P < 0.05). The average incidence of hospitalizations per-patient decreased from 0.30 in 2009, to 0.13 in 2015. Average expenditure per-patient decreased from €10,107 in 2009 to €9063 in 2015.

Conclusions

The present analysis confirmed the role of cART in controlling HIV viral load and, consequently, in reducing hospitalizations, admissions to day-hospital and the use of outpatient services.

Clinical improvements and economic savings more than compensated the investments required to treat HIV-infected patients with cART. Health Authorities should invest in modern cART supply and universal treatment, to use at best the available resources and obtain a cost-effective improvement of health in people living with HIV. Additional research, with the involvement of different centers and the use of patient-specific data, are recommended to consolidate the findings of this analysis.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3507-x) contains supplementary material, which is available to authorized users.

Epic Allies, a Gamified Mobile Phone App to Improve Engagement in Care, Antiretroviral Uptake, and Adherence Among Young Men Who Have Sex With Men and Young Transgender Women Who Have Sex With Men: Protocol for a Randomized Controlled Trial

Background

In the United States, young men who have sex with men (YMSM) and transgender women who have sex with men (YTWSM) bear a disproportionate burden of prevalent and incident HIV infections. Once diagnosed, many YMSM and YTWSM struggle to engage in HIV care, adhere to antiretroviral therapy (ART), and achieve viral suppression. Computer-based interventions, including those focused on behavior change, are recognized as effective tools for engaging youth.

Objective

The purpose of the study described in this protocol is to evaluate the efficacy of Epic Allies, a theory-based mobile phone app that utilizes game mechanics and social networking features to improve engagement in HIV care, ART uptake, ART adherence, and viral suppression among HIV-positive YMSM and YTWSM. The study also qualitatively assesses intervention acceptability, perceived impact, and sustainability.

Methods

This is a two-group, active-control randomized controlled trial of the Epic Allies app. YMSM and YTWSM aged 16 to 24 inclusive, with detectable HIV viral load are randomized 1:1 within strata of new to care (newly entered HIV medical care ≤12 months of baseline visit) or ART-nonadherent (first entered HIV medical care >12 months before baseline visit) to intervention or control conditions. The intervention condition addresses ART adherence barriers through medication reminders and adherence monitoring, tracking of select adherence-related behaviors (eg, alcohol and marijuana use), an interactive dashboard that displays the participant’s adherence-related behaviors and provides tailored feedback, encouragement messages from other users, daily HIV/ART educational articles, and gamification features (eg, mini-games, points, badges) to increase motivation for behavior change and app engagement. The control condition features weekly phone-based notifications to encourage participants to view educational information in the control app. Follow-up assessments are administered at 13, 26, and 39 weeks for each arm. The primary outcome measure is viral suppression. Secondary outcome measures include engagement in care, ART uptake, ART adherence, and psychosocial barriers to engagement in care and ART adherence, including psychological distress, stigma, and social support.

Results

Baseline enrollment began in September 2015 and was completed in September 2016 (n=146), and assessment of intervention outcomes continued through August 2017. Results for primary and secondary outcome measures are expected to be reported in ClinicalTrials.gov by April 30, 2018.

Conclusions

If successful, Epic Allies will represent a novel adherence intervention for a group disproportionately impacted by HIV in the United States. Adherent patients would require less frequent clinic visits and experience fewer HIV-related secondary infections, thereby reducing health care costs and HIV transmission. Epic Allies could easily be expanded and adopted for use among larger populations of YMSM and YTWSM, other HIV-positive populations, and for those diagnosed with other chronic diseases such as diabetes and hypertension.

Trial Registration

ClinicalTrials.gov NCT02782130; https://clinicaltrials.gov/ct2/show/NCT02782130 (Archived by Webcite at http://www.webcitation.org/6yGODyerk)

Early HIV Diagnosis Leads to Significantly Decreased Costs in the First 2 Years of HIV Care in an Urban Charity Hospital in New Orleans

We undertook a retrospective cohort study of patients with a positive HIV test in the emergency department who were then linked to care. Inpatient, outpatient, and emergency costs were collected for the first 2 years after HIV diagnosis. Fifty-six patients met the inclusion criteria; they were predominantly uninsured (73%) and African American (89%). The median total cost for a newly diagnosed patient over the first 2 years was US$36 808, driven predominantly by outpatient costs of US$17 512. Median inpatient and total costs were significantly different between the lowest (<200 cells/mm³) and highest (>499 cells/mm³) CD4 count categories (US$21 878 vs US$6607, P <.05; US$61 378 vs US$18 837, P <.05, respectively). Total costs were significantly different between viral load categories <100 000 HIV-RNA copies/mL and ≥100 000 HIV-RNA copies/mL (US$28 219 vs US$49 482, P <.05). Costs were significantly lower among patients diagnosed earlier in their disease. Decreased cost is another factor supporting early diagnosis and linkage to care for patients with HIV.

A Population-Based Study of Care at the End of Life Among People With HIV in Ontario From 2010 to 2013

BACKGROUND

Aging and increasing comorbidity is changing the end-of-life experience of people living with HIV (PLHIV) in the developed world. We quantified, at a population level, the receipt of health care services and associated costs across a comprehensive set of sectors among decedents with and without HIV.

METHODS

We conducted a retrospective population-level observational study of all decedents in Ontario and their receipt of health care services, captured through linked health administrative databases, between April 1, 2010 and March 31, 2013. We identified PLHIV using a validated algorithm. We described the characteristics of PLHIV and their receipt of health care services and associated costs by health care sector in the last year of life.

RESULTS

We observed 264,754 eligible deaths, 570 of whom had HIV. PLHIV were significantly younger than those without HIV (mean age of death 56.1 years vs. 76.6 years, [P < 0.01]). PLHIV spent a mean of 20.0 days in an acute care hospital in the last 90 days of life compared with 12.1 days for decedents without HIV (P < 0.01); after adjustment, HIV was associated with 4.5 more acute care days (P < 0.01). Mean cost of care in the last year was significantly higher among PLHIV ($80,885.62 vs. $53,869.77), mostly attributable to acute care costs.

INTERPRETATION

PLHIV in Ontario are dying younger, spending more time and dying more often in hospital, and incur significantly increased costs before death. Greater involvement of community-based palliative care may improve the dying experience for this complex population.

Bayesian evidence synthesis to estimate HIV prevalence in men who have sex with men in Poland at the end of 2009

HIV spread in men who have sex with men (MSM) is an increasing problem in Poland. Despite the existence of a surveillance system, there is no direct evidence to allow estimation of HIV prevalence and the proportion undiagnosed in MSM. We extracted data on HIV and the MSM population in Poland, including case-based surveillance data, diagnostic testing prevalence data and behavioural data relating to self-reported prior diagnosis, stratified by age (⩽35, >35 years) and region (Mazowieckie including the capital city of Warsaw; other regions). They were integrated into one model based on a Bayesian evidence synthesis approach. The posterior distributions for HIV prevalence and the undiagnosed fraction were estimated by Markov Chain Monte Carlo methods. To improve the model fit we repeated the analysis, introducing bias parameters to account for potential lack of representativeness in data. By placing additional constraints on bias parameters we obtained precisely identified estimates. This family of models indicates a high undiagnosed fraction [68·3%, 95% credibility interval (CrI) 53·9-76·1] and overall low prevalence (2·3%, 95% CrI 1·4-4·1) of HIV in MSM. Additional data are necessary in order to produce more robust epidemiological estimates. More effort is urgently needed to ensure timely diagnosis of HIV in Poland.

Costs of health resource utilization among HIV-positive individuals in British Columbia, Canada: results from a population-level study

BACKGROUND

Through delayed HIV disease progression, highly active antiretroviral therapy (HAART) may reduce direct medical costs, thus at least partially offsetting therapy costs. Recent findings regarding the secondary preventive benefits of HAART necessitate careful consideration of funding allocations for HIV/AIDS care. Our objective is to estimate non-HAART direct medical costs at different levels of disease progression and over time in British Columbia, Canada.

METHODS

We considered the population of individuals with HIV/AIDS within a set of linked disease registries and health administrative databases (N = 11,836) from 1996 to 2010. Costs of hospitalization, physician billing, diagnostic testing and non-HAART medications were calculated in 2010 Canadian dollars. Effects of covariates on quarterly costs were assessed with a two-part model with logit for probability of non-zero costs and a generalized linear model (GLM). Net effects of CD4 strata on direct non-HAART medical costs were evaluated over time during the study period.

RESULTS

Compared with person-quarters in which CD4 >500/mm(3), costs were Can$185 (95 % confidence interval [CI] 132-239) greater for CD4 350-500/mm(3), Can$441 (95 % CI 366-516) greater for CD4 200-350/mm(3) and Can$1,173 (95 % CI 1,051-1,294) greater when CD4 <200/mm(3). Prior to HIV care initiation, individuals incurred costs Can$385 (95 % CI 283-487) greater than in periods with CD4 >500/mm(3). Hospitalization comprised the majority of the increment in costs amongst those with no measured CD4. Evaluated at CD4 state conditional means, those with CD4 <200/mm(3) incurred quarterly costs of Can$5,781 (95 % CI 4,716-6,846) versus Can$1,307 (95 % CI 1,154-1,460; p < 0.001) for CD4 ≥500/mm(3) in 2010.

CONCLUSION

Non-HAART direct medical costs were substantially lower for individuals during periods of sustained virologic suppression and high CD4 count. HIV treatment and prevention evaluations require detailed health resource use data to inform funding allocation decisions.

Cost-effectiveness analysis of antiretroviral therapy in a cohort of HIV-infected patients starting first-line highly active antiretroviral therapy during 6 years of observation

Objectives

Costs may play a role in deciding how and when to start highly active antiretroviral therapy (HAART) in a naïve patient. The aim of the present study was to assess the cost- effectiveness of treatment with HAART in a large clinical cohort of naïve adults to determine the potential role of single-tablet regimens in the management of patients with human immunodeficiency virus (HIV). An incremental cost-effectiveness ratio analysis was performed, including a quality-adjusted life year approach.

Results

In total, 741 patients (females comprising 25.5%) were retrospectively included. The mean age was 39 years, the mean CD4 cell count was 266 cells/μL, and the mean viral load was 192,821 copies/mL. The most commonly used backbone was tenofovir + emtricitabine (77.6%); zidovudine + lamivudine was used in 10%, lamivudine + abacavir in 3%, and other nucleoside reverse transcriptase inhibitor (NRTI) or NRTI-free regimens in 9.4% of patients. NNRTIs were used in 52.8% of cases, boosted protease inhibitors in 44.1%, and unboosted protease inhibitors and integrase inhibitors in 0.7% and 2.4%, respectively. Starting therapy at CD4 >500 cells/μL and CD4 351–500 cells/μL rather than at <201 cells/μL was the more cost-effective approach. The same consideration was not true comparing current indications with the possibility to start HAART at any CD4 value (eg, >500 cells per μL); in this case, the incremental cost-effectiveness ratio value was €199,130 per quality-adjusted life year gained, a higher value than the one suggested in guidelines. The single-tablet regimen (STR) invariably dominated any other therapeutic approach. Sensitivity analysis was performed, and starting right away with an STR was cost-effective even when compared with therapeutic strategies contemplating STR as simplification.

Conclusion

By integrating clinical data with economic variables, our study offers an estimate of the cost-effectiveness of the various first-line treatment strategies for patients infected with HIV and provides significant evidence to be used in future prospective pharmacoeconomic evaluations.

Estimation of the Direct Cost of HIV-Infected Patients in Greece on an Annual Basis

OBJECTIVE

HIV infection is currently regarded as a global chronic disease. The purpose of this study was to assess the direct cost of illness per patient per year in Greece.

METHODS

A retrospective study for the estimation of the direct cost of HIV infection was performed from the third-party payer perspective. Data from 447 patients monitored in a general hospital of Athens were collected from their medical records. The survey involved all services and treatments that patients (stratified into three health states according to the number of CD4 cells/ml as defined by the Centers for Disease Control and Prevention classification system for HIV infection) received in 1 year, as well as demographic data.

RESULTS

The annual direct cost per patient was calculated at €6859 ± €4699. Antiretroviral therapy cost was estimated at €5741, while the annual cost of providing health care services regardless of health state was computed at €1118, with laboratory investigation and imaging studies representing €924 (13.5%), outpatient visits €34 (0.5%), and hospitalization €160 (2.3%) of total cost, respectively. Overall, direct cost per patient was found to increase as the CD4 T lymphocytes decreased, leading to prolonged hospitalization and an increase in the number of laboratory tests. Direct cost for patients with more than 500 CD4 cells/μl was estimated at €6067, whereas for those with 200 to 499 cells/μl and less than 200 cells/μl, it was assessed at €6857 and €7654, respectively.

CONCLUSIONS

The direct cost of HIV infection per patient increased as CD4 T lymphocytes decreased. The largest part of expenses was attributed to antiretroviral therapy, followed by laboratory tests/imaging studies, hospitalization, and finally outpatient visits.

Costing analysis of national HIV treatment and care program in Vietnam

Supplemental Digital Content is Available in the Text.

Background:

Vietnam achieved rapid scale-up of antiretroviral therapy (ART), although external funds are declining sharply. To achieve and sustain universal access to HIV services, evidence-based planning is essential. To date, there had been limited HIV treatment and care cost data available in Vietnam.

Methods:

Cost data of outpatient and inpatient HIV care were extracted at 21 sentinel facilities (17 adult and 4 pediatric) that epitomize the national program. Step-down costing for administration costs and bottom-up resource costing for drugs, diagnostics, and labor were used. Records of 1401 adults and 527 pediatric patients were reviewed.

Results:

Median outpatient care costs per patient-year for pre-ART, first year ART, later year ART, and second-line ART were US $100, US $316, US $303, and US $1557 for adults; and US $171, US $387, US $320, and US $1069 for children, respectively. Median inpatient care cost per episode was US $162 for adults and US $142 for children. Non-antiretroviral (ARV) costs in adults at stand-alone facilities were 44% (first year ART) and 24% (later year ART) higher than those at integrated facilities. Adults who started ART with CD4 count ≤100 cells per cubic millimeter had 47% higher non-ARV costs in the first year ART than those with CD4 count >100 cells per cubic millimeter. Adult ARV drug costs at government sites were from 66% to 85% higher than those at donor-supported sites in the first year ART.

Conclusions:

The study found that HIV treatment and care costs in Vietnam are economical, yet there is potential to further promote efficiency through strengthening competitive procurement, integrating HIV services, and promoting earlier ART initiation.

HIV-1 disease progression during highly active antiretroviral therapy: an application using population-level data in British Columbia: 1996-2011

BACKGROUND

Accurately estimating rates of disease progression is of central importance in developing mathematical models used to project outcomes and guide resource allocation decisions. Our objective was to specify a multivariate regression model to estimate changes in disease progression among individuals on highly active antiretroviral treatment in British Columbia, Canada, 1996-2011.

METHODS

We used population-level data on disease progression and antiretroviral treatment utilization from the BC HIV Drug Treatment Program. Disease progression was captured using longitudinal CD4 and plasma viral load testing data, linked with data on antiretroviral treatment. The study outcome was categorized into (CD4 count ≥ 500, 500-350, 350-200, <200 cells/mm, and mortality). A 5-state continuous-time Markov model was used to estimate covariate-specific probabilities of CD4 progression, focusing on temporal changes during the study period.

RESULTS

A total of 210,083 CD4 measurements among 7421 individuals with HIV/AIDS were included in the study. Results of the multivariate model suggested that current highly active antiretroviral treatment at baseline, lower baseline CD4 (<200 cells/mm), and extended durations of elevated plasma viral load were each associated with accelerated progression. Immunological improvement was accelerated significantly from 2004 onward, with 23% and 46% increases in the probability of CD4 improvement from the fourth CD4 stratum (CD4 < 200) in 2004-2008 and 2008-2011, respectively.

CONCLUSION

Our results demonstrate the impact of innovations in antiretroviral treatment and treatment delivery at the population level. These results can be used to estimate a transition probability matrix flexible to changes in the observed mix of clients in different clinical stages and treatment regimens over time.

The presence of CD4 counts for the management of HIV patients in East Africa: a multicentred study

New WHO guidance stipulates six-monthly CD4 testing and treatment initiation at CD4 less than 350. This study aimed to determine the presence of CD4 results in patient records across five care facilities in Kenya, and to identify factors associated with the presence of CD4 count. This is a cross-sectional study of consecutive outpatients. Participants completed self-reported outcomes of demographics, and both physical and mental health dimensions of quality of life and function; charts were reviewed for a CD4 count in the previous 13 months; 548 patients participated. For those diagnosed during the 13-month study period, 7.1% of the sample had no CD4 result on record. For those diagnosed prior to the study, 8.7% had no result. Multivariate logistic regression revealed that 30 days post-HIV diagnosis, facility and antiretroviral therapy use were associated with the odds of having a CD4 result on file. At six months, poverty and prevalence of multidimensional problems were associated with lack of CD4 result. For those diagnosed prior to the observation period, education level was associated with more infrequent CD4 counts, and facility and number of dependants were associated with odds of a CD4 result within six months. Our data suggest inconsistencies in CD4 results availability within and between facilities. Implementation of new guidance will require a shift in practice.

[Assessment of the impact of the new health legislation on illegal immigrants in Spain: the case of human immunodeficiency virus infection]

The immigrant population in Spain, whether legal or not, has been entitled to healthcare under the same conditions as the Spanish population since the year 2000. The entry into vigour of the Royal Decree-Law 12/2012 of 20 April has significantly restricted this right, so that unauthorized or non-resident foreigners may now only receive emergency care, if they are under 18 or pregnant women. Out of an estimated 459,909 illegal immigrants in our country, 2,700 to 4,600 are probably infected with HIV; 1,800 to 3,220 know that they are infected, and 80% of the latter could receive antiretroviral treatment. The Royal Decree-Law is likely to cause many undesirable consequences in this population infected with HIV: increasing mortality, promoting the emergence of opportunistic diseases, increasing hospital admissions, increasing infections in the population (by HIV and other pathogens), or contributing to mother to child transmission of HIV. The expected increase in morbidity and mortality will be a greater cost in patient care, a cost which will be significantly higher in the more immunosuppressed patients. Therefore, the enforcement of the Royal Decree-Law will be much less cost-effective in the short term than was expected, and will negatively affect our country's public health, especially for those patients infected with HIV who will not be covered, thus increasing healthcare medium to long term costs, and moving away from the international health goals that were established.

A call to action for comprehensive HIV services for men who have sex with men

Where surveillance has been done, it has shown that men (MSM) who have sex with men bear a disproportionate burden of HIV. Yet they continue to be excluded, sometimes systematically, from HIV services because of stigma, discrimination, and criminalisation. This situation must change if global control of the HIV epidemic is to be achieved. On both public health and human rights grounds, expansion of HIV prevention, treatment, and care to MSM is an urgent imperative. Effective combination prevention and treatment approaches are feasible, and culturally competent care can be developed, even in rights-challenged environments. Condom and lubricant access for MSM globally is highly cost effective. Antiretroviral-based prevention, and antiretroviral access for MSM globally, would also be cost effective, but would probably require substantial reductions in drug costs in high-income countries to be feasible. To address HIV in MSM will take continued research, political will, structural reform, community engagement, and strategic planning and programming, but it can and must be done.

A review of economic evaluations of darunavir boosted by low-dose ritonavir in treatment-experienced persons living with HIV infection

Darunavir boosted by low-dose ritonavir (DRV/r), at a daily dose of 600/100 mg twice a day (bid), has been shown to be superior to alternative highly active antiretroviral therapy (HAART) regimens for the management of treatment-experienced, HIV-infected adults in the phase IIb POWER trials and the phase III TITAN trial. Economic analyses of different types that have been performed for several countries to investigate the cost effectiveness and budgetary impact of DRV/r 600/100 mg bid for treatment-experienced people living with HIV (PLHIV) based on the clinical data gathered in the POWER and TITAN trials are reviewed for consistency and their value to different decision-makers is assessed. Cost-utility analyses for the USA and several European countries indicate that DRV/r-based HAART is cost effective compared with other standard of care protease inhibitor (PI)-based regimens in PLHIV with evidence of PI resistance. For all of these countries, the estimated cost-utility ratio is well below typical benchmark values and these ratios are robust, as demonstrated by one-way sensitivity and variability analyses and multi-way probabilistic sensitivity analyses. Studies using other metrics including the average 1-year drug cost per patient with a plasma HIV-RNA level less than 50 copies/mL at 48 weeks, the incremental drug cost per additional patient with a plasma HIV-RNA level less than 50 copies/mL at 48 weeks, the total (antiretroviral and non-antiretroviral) costs during the first year of treatment, and the total healthcare budget impact during the first 5 years of treatment provided further evidence of the positive economic outcomes with the use of DRV/r in treatment-experienced PLHIV. Different measures of economic outcomes are useful for different types of decision-makers and different types of decisions. In general, the results of these different types of analyses will be consistent with each other. For darunavir, the economic analyses reviewed in this paper demonstrate that the use of DRV/r 600/100 mg bid in the management of HIV-infected, treatment-experienced adults who have failed at least one of the other currently available PIs is cost effective and may be cost saving.

Cost effectiveness of darunavir/ritonavir 600/100 mg bid in protease inhibitor-experienced, HIV-1-infected adults in Belgium, Italy, Sweden and the UK

BACKGROUND

Two phase II trials (POWER 1 and 2) have demonstrated that darunavir co-administered with low-dose ritonavir (DRV/r) provides significant clinical benefit compared with control protease inhibitors (PIs) in highly treatment-experienced, HIV-1-infected adults, when co-administered with optimized background therapy (OBR).

OBJECTIVE

To determine whether DRV/r is cost effective compared with control PIs, from the perspective of Belgian, Italian, Swedish and UK reimbursement authorities, when used in treatment-experienced patients similar to those included in the POWER 1 and 2 trials.

METHODS

An existing Markov model containing health states defined by CD4 cell count ranges (> 500, 351-500, 201-350, 101-200, 51-100 and 0-50 cells/mm³) and death was adapted for use in four European healthcare settings. Baseline demographics, CD4 cell count distribution and antiretroviral drug usage reflected those reported in the POWER 1 and 2 trials. Virological/immunological response rates and matching transition probabilities over the patient's lifetime were based on results from the POWER trials and published data. After treatment failure, patients were assumed to switch to a tipranavir-containing regimen plus OBR. For each CD4 cell count range, utility values and HIV-related mortality rates were obtained from the published literature. National all-cause mortality data and published data on the increased risk of non HIV-related mortality in HIV-infected individuals were taken into account in the model. Data from observational studies conducted in each healthcare setting were used to determine resource-use patterns and costs associated with each CD4 cell count range. Unit costs were derived from official local sources; a lifetime horizon was taken and discount rates were selected based on local guidelines.

RESULTS

In the base-case analysis, quality-adjusted life-year (QALY) gains of up to 1.397 in Belgium, over 1.171 in Italy, 1.142 in Sweden and 1.091 in the UK were predicted when DRV/r-based therapy was used instead of control PI-based treatment. The base-case analyses predicted an incremental cost-effectiveness ratio (ICER) of €11,438/QALY in Belgium, €12,122/QALY in Italy,€10,942/QALY in Sweden and €16,438/QALY in the UK. Assuming an acceptability threshold of €30,000/QALY, DRV/r-based therapy remained cost effective over all parameter ranges tested in extensive one-way sensitivity analyses. Probabilistic sensitivity analysis revealed a 95% (Belgium), 97% (Italy), 92% (Sweden) or 78% (UK) probability of attaining an ICER below this threshold.

CONCLUSION

From four European payer perspectives, DRV/r-based antiretroviral therapy is predicted to be cost effective compared with currently available control PIs, when both are used with an OBR in treatment-experienced, HIV-1-infected adults who failed to respond to more than one PI-containing regimen.

Predicting direct costs of HIV care during the first year of darunavir-based highly active antiretroviral therapy using CD4 cell counts: evidence from POWER

BACKGROUND

Given the association between CD4 cell counts and HIV-related morbidity/mortality, new antiretroviral therapies could potentially lower the direct costs of HIV care by raising CD4 cell counts.

OBJECTIVES

To predict the effects of the ritonavir-boosted, HIV protease inhibitor (PI) darunavir on the direct costs of care, while accounting for CD4 cell counts, during the first year of therapy in highly treatment-experienced, HIV-infected adults in different healthcare settings.

METHODS

The mean annual per-patient cost of darunavir/ritonavir (DRV/r) and control PI-based highly active antiretroviral therapy (HAART) was calculated from the proportional use of antiretroviral agents in the DRV/r and control PI arms of the pooled POWER 1 and 2 trials, applying drug-acquisition costs for five healthcare settings. Non-antiretroviral-related costs by CD4 cell count, derived from non-interventional studies in the same settings, were applied to the POWER data (proportion of patients with CD4 cell counts in different strata at week 48) to estimate mean annual non-antiretroviral-related costs per patient in patients receiving DRV/r or control PI-based HAART during year 1.

RESULTS

Across all settings, the mean annual per-patient cost of DRV/r-based treatment was 2-19% higher than that of control PI-based therapy during the first year of therapy. By raising CD4 cell counts, however, DRV/r-based regimens were predicted to lower mean annual non-antiretroviral-related costs by 16-38% compared with control PI-based therapy. When combined, the total annual per-patient cost of HIV care during the first year of therapy was estimated to be 7% lower in the DRV/r compared with the control PI arm using US data, 8% lower using Swedish data, budget neutral using UK and Belgian data and 5% higher using Italian data.

CONCLUSIONS

Darunavir-based HAART may lower non-antiretroviral-related costs compared with control PI-based therapy in highly treatment-experienced, HIV-infected patients during the first year of therapy by improving patients' CD4 cell counts. These costs could partly/fully offset the increased acquisition cost of DRV/r in this patient population over the same period.

The cost of managing HIV infection in highly treatment-experienced, HIV-infected adults in France

BACKGROUND

Highly active antiretroviral therapy (HAART) has greatly enhanced HIV management, lowering the risk of clinical disease progression and death by substantially improving HIV-induced immune deficiency. Lower CD4 cell counts have consistently been associated with higher direct costs of HIV patient care. The aim of this study was to analyze HIV costs of care in France at different levels of HIV-induced immune deficiency (as measured by the CD4 cell count) using recent data from treatment-experienced patients.

METHODS

This analysis used data from the French Hospital Database in HIV, containing data on approximately 50% of the French HIV population. Patients were included in the analysis if they had visited a participating centre from 2003 to 2005, had CD4 cell counts determined at least twice during the study period, and had been prescribed at least two nucleoside reverse transcriptase inhibitors, one non-nucleoside reverse transcriptase inhibitor and two protease inhibitors since their first consultation. Resources consumed were counted and aggregated according to the CD4 cell count level. Standard costs were applied.

RESULTS

Periods with the lowest CD4 cell counts were associated with increased prescription rates of antiviral agents (other than anti-HIV agents), antiparasitic drugs and antimycobacterial agents. Antiretroviral treatments accounted for 80% of all medications prescribed during the study period. Hospitalization rates decreased with increasing CD4 cell counts, with 0.72 hospitalizations per patient-year for those with CD4 cell counts of 50 cells/mm³ or less compared with 0.05 per patient-year for patients with CD4 cell counts greater than 500 cells/mm³. There was a clear trend towards lower mean healthcare costs per patient-year with decreasing immune deficiency; from €34,286 to €12,361.

CONCLUSIONS

Our study showed an association between the degree of HIV-induced immune deficiency (measured by CD4 cell count) and the costs of managing HIV infection among highly pre-treated, HIV-infected individuals in France in the HAART era.

Cost effectiveness of darunavir/ritonavir 600/100 mg bid in treatment-experienced, lopinavir-naive, protease inhibitor-resistant, HIV-infected adults in Belgium, Italy, Sweden and the UK

BACKGROUND

Using data from the phase IIb POWER trials, darunavir boosted with low-dose ritonavir (DRV/r; 600/100 mg twice daily; bid)-based highly active antiretroviral therapy (HAART) was shown to be significantly more efficacious and cost effective than other protease inhibitor (PI)-based therapy in highly treatment-experienced, HIV-1-infected adults. Furthermore, in the phase III TITAN trial (TMC114-C214), DRV/r 600/100 mg bid-based HAART generated a superior 48-week virological response rate compared with standard-of-care lopinavir/ritonavir (LPV/r; 400/100 mg bid)-based therapy in treatment-experienced, lopinavir-naive patients, and in particular those with one or more International AIDS Society - USA (IAS-USA) primary PI resistance-associated mutations at baseline. These patients had a broader degree of previous PI use/failure (0 - ≥ 2) than the POWER patients.

OBJECTIVES

To determine whether DRV/r 600/100 mg bid-based HAART is cost effective compared with LPV/r-based therapy, from the perspective of Belgian, Italian, Swedish and UK reimbursement authorities, when used in treatment-experienced patients similar to TITAN patients with one or more IAS-USA primary PI mutations at baseline.

METHODS

An existing Markov model containing health states defined by CD4 cell count ranges (>500, 351-500, 201-350, 101-200, 51-100 and 0-50 cells/mm³) and an absorbing state of death was adapted for use in the above-mentioned healthcare settings. Baseline demographics, CD4 cell count distribution, antiretroviral drug usage, virological/immunological response rates and matching transition probabilities were based on data collected during the first 48 weeks of therapy in the modelled subgroup of TITAN patients and the published literature. After treatment failure, patients were assumed to switch to a follow-on combination regimen. For each health state, utility values and mortality rates were obtained from the published literature. Data from local observational studies (Belgium, Sweden and Italy) or the published literature (UK) were used to determine resource-use patterns and costs associated with each CD4 cell count range. Unit costs were derived from official local sources; a lifetime horizon was taken and discount rates were chosen based on local guidelines.

RESULTS

The base-case analysis predicted quality-adjusted life year (QALY) gains of 0.785 in Belgium, 0.608 in Italy, 0.584 in Sweden and 0.550 in the UK when DRV/r-based therapy was used instead of LPV/r-based treatment. The estimated base-case incremental cost-effectiveness ratios (ICERs) were €6964/QALY gained in Belgium, €9277/QALY gained in Italy, €6868 (SEK69,687)/QALY gained in Sweden and €14,778 (£12 612)/QALY gained in the UK. Assuming a threshold of €30,000/QALY gained, DRV/r-based therapy remained cost effective over most parameter ranges tested in extensive one-way sensitivity analyses. The variation of immunological response rates and the time horizon were identified as important drivers of cost effectiveness. Probabilistic sensitivity analysis revealed a greater than 70% probability of achieving an ICER below this threshold in all four healthcare settings.

CONCLUSION

From the perspective of Belgian, Italian, Swedish and UK payers, DRV/r 600/100 mg bid-based HAART is predicted to be cost effective compared with LPV/r 400/100 mg bid-based therapy, when used to manage treatment experienced, lopinavir-naive, PI-resistant, HIV-infected adults with a broad range of previous PI use/failure.