world aids day 2016: economic evaluation for hiv in south africa
TRANSCRIPT
Using Economic Evaluation to Strengthen South Africa’s National HIV Program:
Boston University’s ExperienceSydney Rosen
Department of Global HealthBoston University School of Public Health
Health Economics and Epidemiology Research Office, University of the Witwatersrand
December 1, 2016
What To Expect Today• Ten minutes about economic evaluation• The setting: a safari to South Africa• How much does it cost?• Is it cost-effective?• What are the benefits?• Can we afford to do what we want?• Final thoughts (if any are left)
With thanks to all the colleagues whose work I’ve borrowed…
Ten Minutes About Economic Evaluation
Economics is about the allocation of scarce resources to meet competing ends• What resources do we have?
• What are our goals (ends)?
• Who decides?
• Who wins?
• Who loses?
• Economics is about value (and values), not money. Money is merely a unit of measurement.
Economic evaluation is about how to allocate resources under constraint• Allocating resources: Deploying our constrained resources to
achieve our goals over space and time
• Minimizing costs: Choosing strategies to spend the least we can to generate the outcomes or impacts we want
• Maximizing benefits: Getting the most health and other desirable outcomes from the resources we have
• Various other things that we won’t talk about today
Within the world of evaluation…
Can it work? (Efficacy)
Does it work? (Effectiveness)
Is it feasible to implement in the setting we care
about? (Feasibility)
How much does it cost, and can we
afford it?Is it cost-effective? Do the benefits
exceed the costs?
Source: Drummond et al, Methods for the Economic Evaluation of Health Care Programmes, 2005
Some types of economic evaluation• Value of changes in resources used• Can be incremental or total costCost
• Cost per successful health outcome achieved• Outcomes are natural (meaningful) units of healthCost/outcome
• Difference in cost per successful outcome achieved • Comparison between options with same outcomeCost/effectiveness
• Cost per unit of utility gained or disutility avoided• DALYs or QALYs can combine multiple or disparate outcomesCost/utility
• Ratio of value of total costs to value of total benefits• Costs and benefits are valued in monetary units and presented as
net benefits (= benefits-costs) Cost/benefit
More about types of evaluationApproach Question Definition and uses
Incremental cost
How much more does it cost than what I’m already spending?
Additional cost of adding an additional service, per patient served; budgeting to scale up additional service
Total cost How much should I budget? Total cost per patient to achieve the outcomes being evaluated; budgeting to provide service to a specified number of patients
Cost/outcome How much does it cost to get the outcomes I want?
Average cost per successful or unsuccessful outcome achieved; monitoring changes and identifying opportunities for better resource allocation
Cost-effectiveness
How does my intervention compare to standard care or other interventions with the same outcome?
Difference in costs divided by difference in specific health outcomes; comparing different service delivery strategies for achieving a single outcome
Cost-utility How does my intervention compare to other health interventions with different or multiple outcomes?
Difference in costs divided by difference in utility outcomes (QALYs, DALYs); determining whether an intervention is a “good buy” compared to dissimilar interventions or a threshold
Cost-benefit Do the benefits of my intervention exceed the costs?
Ratio of costs to benefits, in monetary terms; deciding whether the service should be provided at all
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Cost-effectiveness is not all it’s cracked up to be
Cost-effectiveness analysis is a comparison between options
• A new intervention compared to standard of care• One intervention compared to another intervention
Each intervention has a cost, expressed in monetary terms
Each intervention has an effect, expressed in health or utility terms
• For example, proportion of patients achieving viral suppression, or disability adjusted life years (DALYs)
Cost-effectiveness does not tell us if something is “worth it”. Let’s see what it does tell us.
When is cost-effectiveness analysis useful?
Effectiveness
Cos
t
Cost of status quoE
ffect
iven
ess
of s
tatu
s qu
oHigher or equal cost, lower effectiveness—almost never do it
Lower cost, lower effectiveness—only do it to reduce budget
Higher cost, higher effectiveness—do it if it’s affordable and cost-effective compared to alternatives
Lower cost, higher or equal effectiveness—almost always do it
✔
?
?
• Minimize cost to achieve a predetermined target—for example, 90-90-90• Maximize benefits for a predetermined cost—for example, a national budget• Compare two approaches to achieving the same health outcomes—for
example, a new drug or device compared to an existing one--BUSPH Professor Bruce Larson
Last and least: What exactly is an ICER?
An ICER is an Incremental Cost Effectiveness Ratio
ICER =Difference in costs
Difference in effects
Standard careCost = $8,000Effects = 10 units of health
New interventionCost = $12,000Effects = 14 units of health
Difference in costs = $4000Difference in effects = 4 unitsICER = $1000
Is an ICER of $1000 worth it? It depends on two main things:
What is the value of a unit of health?What is the alternative use of the resources?
Upshot: Context matters. Whether something is cost-effective or not depends on the comparison in question and can vary widely (if not wildly) by place, time, and situation. A thing cannot be “cost-effective” in the abstract.
What To Expect Today• Ten minutes about economic evaluation• The setting: a safari to South Africa• How much does it cost?• Is it cost-effective?• What are the benefits?• Can we afford to do what we want?• Final thoughts (if any are left)
The Setting: South Africa
HIV prevalence 2014
The problemSub-Saharan Africa has the most severe HIV/AIDS epidemic in the world and southern Africa the most severe in Africa.
HIV prevalence adults 15-49 in 2013 (UNAIDS)
In South Africa:• Adult HIV prevalence is estimated at 19%:
- 7 million HIV-positive people- 19% of global burden (0.7% of global
population)- Nearly 300,000 new infections/year
• HIV and tuberculosis are the two leading causes of adult deaths; 70% of TB patients have HIV co-infection
• Life expectancy at birth fell from 62 in 1995 to 52 in 2010
Sources: Stats SA, National Department of Health, UN Population Division
The solution
• An estimated 3.4 million patients are on ART (just under half the HIV-positive population)
• Among those on ART, 78% are virally suppressed
• Mortality has declined and life expectancy is rising
• Adult incidence is declining and vertical transmission is < 2%
• Large-scale, public sector provision of ART began in 2004
The need for efficient resource allocation• In September 2016, South Africa adopted “treat all” guidelines; all HIV-positive
individuals are eligible for ART
• For the country to reach its first two “90-90-90” targets (90% diagnosed, 90% on treatment), > 2.4 million more people must be placed on ART
• The estimated additional cost of this is about $1 billion/year, or about a 60% increase over current expenditure on HIV (SA funds 85% of its own HIV program; poorer countries fund very little)
• The South African economy is weak, with low growth and unemployment at 36%, and donor funding is unlikely to increase
• Economic evaluation (combined with some clever modeling) is helping South Africa decide how to allocate its constrained resources as efficiently as possible to maximize health benefits
Source: Stats SA; personal communication, Gesine Meyer-Rath
• The Department of Global Health at BUSPH began collaborating with the University of the Witwatersrand (Wits University) in Johannesburg in 2004.
• We helped to found HE2RO, the Health Economics and Epidemiology Research Office, in partnership with Wits.
• In collaboration with HE2RO, we’ve been conducting applied research on the economics and epidemiology of the HIV epidemic for > 10 years.
• We work closely with the South African Government, particularly the National Department of Health, to inform its policies.
• HE2RO now has ≈ 60 investigators and staff and dozens of studies.
• Funders include USAID, the NIH, the Gates Foundation, the CDC, the World Bank, and others.
BUSPH’s partnership in South Africa
What To Expect Today• Ten minutes about economic evaluation• The setting: a safari to South Africa• How much does it cost?• Is it cost-effective?• What are the benefits?• Can we afford to do what we want?• Final thoughts (if any are left)
How Much Does It Cost?
• Cost and price are not the same: I produce something at its cost; I sell it at its price
• Costs are independent of source of funding• We typically discount and inflate future costs
(and benefits)
Cost = monetary value of resources utilized to provide a service or achieve an outcome
• NO: “HIV treatment costs $10,000.”• YES: “In 2016, first-line HIV treatment per
patient per 12-month period in the United States, delivered on an outpatient basis and including medications, laboratory tests, clinic visits, patient management, and overhead for these services cost, Medicaid average of $10,000 (USD 2016).”
Cost to whom, when, for what, for how long?
How much does it cost is a loaded question
How much does HIV treatment cost in South Africa?
All outcomes In care and responding
In care but not responding
No longer in care
$-
$200
$400
$600
$800
$1,000
$1,200
$1,400
Site 1 (hospital based HIV clinic) Site 2 (NGO clinic)
Site 3 (NGO clinic) Site 4 (private GPs)
Cos
t per
pat
ient
(200
6 U
SD
)
• Study conducted in 2005-2006
• Retrospective cohort with chart review and unit cost data collection
• Primary outcome = adult patient “in care and responding” 12 months after ART initiation
• Perspective = provider (Department of Health)
• Included all resources used to provide outpatient ART
• First empirical data on actual cost of providing ART in Africa Today, first-line ART in South Africa costs about
$200/patient/year. In the U.S. it is $10,000-$20,000.
What To Expect Today• Ten minutes about economic evaluation• The setting: a safari to South Africa• How much does it cost?• Is it cost-effective?• What are the benefits?• Can we afford to do what we want?• Final thoughts (if any are left)
Is It Cost-Effective?
Cost-effectiveness of task-shifting and decentralization
• Two strategies for maintaining stable patients on ART:- Centralized, full-service HIV
clinics- Primary health clinics
• Why use cost-effectiveness analysis?- Minimize cost to achieve a pre-
determined outcome (viral suppression) for maximum number of patients
• Evaluation of a pilot implementation project following an RCT- RCT controlled for everything- Pilot was somewhere between
RCT and routine care
Centralized PHC
Effects (% of cohort in care and responding at 12 months)
90% 96%
Costs (average cost/patient for 12 months)
$539 $486
Most improvements in health are not cost-saving. In general, we don’t get more for less. We get more for more, and less for less.
An example of getting more for more—the RapIT study• Randomized trial of same-day
ART initiation for adult patients- Used point-of-care tests and
accelerated procedures- Patients could be dispensed ARVs
on the day of their first clinic visit, compared to 4-6 visits required under standard care
- Outcomes = ART initiation < 90 days and viral suppression < 10 months
• Intervention was effective, increasing - ART initiation by 36% - Viral suppression by 26%
• Intervention cost more. Cost per patient achieving primary outcome=- $524 in rapid arm- $483 in standard arm
Is $780 (base case) or $220 (best case) per additional patient virally suppressed cost-effective? It depends on what other ways there are to achieve it…and on the value of the outcome.
A useful application of cost-effectiveness analysis: screening costs versus treatment savings
• South Africa endorsed two strategies for identifying cryptococcal meningitis in HIV patients- Reflexive CrAg screening for all
patients with CD4 < 100- Provider-initiated CrAg screening
based on clinician’s decision- Which is a better strategy?
• Cost-effectiveness model developed using programmatic data from pilot screening programs in South Africa- Reflexive strategy was more
effective (saved more lives) and- Costs for treatment were lower
under reflexive approach, but- Costs for screening were higher
under reflexive strategy
Per 100,000 CD4 counts Reflexive screening
Provider initiated
screening
Difference (reflexive - provider initiated)
Number screened 9,500 1,536 7,964
Cost of screening $47,044 $9,508 $37,536
Cost of treatment $209,399 $264,564 -$55,165
Total cost $256,443 $274,072 -$17,629
Number of additional surviving patients 148 118 30
Total years of life saved 3,189 2,542 647
Cost per life year saved $80 $108 -$27
Reflexive screening is clearly cost-effective compared to provider-initiated screening, because savings on treatment more than offset costs of screening. But Government has to pay for screening up front, in a lump sum; treatment costs are incurred less conspicuously.
Using cost-effectiveness analysis to inform policyIntervention ICER ($/Life-year saved)Condom availability Cost saving Male medical circumcision Cost saving ART at current guidelines (CD4 < 500) 106 PMTCT 138 Universal treatment (“treat all”) 243 Infant testing at 6 weeks 274 SBCC campaign (HCT, reduction in MSP) 761 SBCC campaign (condoms) 1,216General population HCT 1,233 SBCC campaign 3 (condoms, HCT, MMC) 1,819 HCT for sex workers 2,644 Infant testing at birth 2,937 PrEP for sex workers 9,894 HCT for adolescents 19,546 PrEP for young women 26,216 Early infant male circumcision 53,785,494
Source: Meyer-Rath et al, Optimising South Africa’s HIV response: Results of the HIV and TB Investment Case, CROI 2016
What To Expect Today• Ten minutes about economic evaluation• The setting: a safari to South Africa• How much does it cost?• Is it cost-effective?• What are the benefits?• Can we afford to do what we want?• Final thoughts (if any are left)
What Are the Benefits?
Benefits can be estimated, but it’s a lot of work
• Prospective, adult cohort followed for six years after ART initiation
• 879 patients interviewed at routine clinic visits (average 8 interviews per patient)
• Study focused on general wellness, activities, employment
• Probability of not being able to do normal activities in previous week fell from 47% before starting treatment to 5% at 5 years
• Employment increased from 32% to 44%
A major benefit: patients on ART can go back to work and contribute to the economy
Comparison of productivity between HIV-negative workers and HIV-positive workers on ART
We could estimate the overall benefits of ART using data like these…but we rarely do. The decision to provide ART to all was political, not economic.
What To Expect Today• Ten minutes about economic evaluation• The setting: a safari to South Africa• How much does it cost?• Is it cost-effective?• What are the benefits?• Can we afford to do what we want?• Final thoughts (if any are left)
Can We Afford To Do What We Want?
Cost-effectiveness doesn’t matter if you can’t afford it
Country GDP/capita Health expenditure/capita (USD 2014)
Estimated cost of ART/patient/year
South Africa $5,692 $570 $263 (2015)
Kenya $1,377 $78 $249 (2013)
Malawi $381 $29 $135 (2016)
India $1,582 $75 No data
China $7,925 $420 No data
U.S. $55,837 $9,403 >$10,000Sources: World Bank; unpublished reports
HIV treatment is extremely effective. Its cost has plummeted (except in the U.S.). But can we afford it?
The South African HIV Investment Case
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Total cost of HIV programme
Baseline Government targetsUnconstrained optimisation Constrained optimisationBudget Constraint Linear (Budget Constraint)90/90/90
US
D (b
illio
ns)
National Department of Health and South African National AIDS
Council
What To Expect Today• Ten minutes about economic evaluation• The setting: a safari to South Africa• How much does it cost?• Is it cost-effective?• What are the benefits?• Can we afford to do what we want?• Final thoughts (if any are left)
Final Thoughts
Why should we care about economics? “Cost is never the first, but almost always the second
consideration in rolling out an intervention. As such it stands between evidence and implementation.”
--BUSPH Assistant Professor Gesine Meyer-Rath Resources are always constrained. There are always
options. Economics helps us choose. Economics is about benefits, not just costs. It forces
us to confront our values. How much is a specific health benefit to someone (else) worth?
Economic evaluation can incorporate considerations of equity and fairness, but only if we are willing to make explicit the values or weights we place on these things.
Last and least: When to call an economist Wrong answer: After we’ve finished our randomized,
controlled clinical trial and suddenly realize that it would be nice to know if our intervention is cost-effective.
Right answer: At the start of our study, to design it in a way that will make the results generalizable and capture all the resources used.
Wrong answer: To prove that we can afford what we’ve already decided to do, regardless of our resources.
Right answer: To decide what we can afford to do, for whom, when, and how, given our resource constraints.
Acknowledgements• BUSPH South Africa team: Gesine Meyer-Rath, Matthew
Fox, Jacob Bor, Bruce Larson, Alana Brennan, and others• HE2RO: Lawrence Long, Mhairi Maskew, Ian Sanne, and
others• Funders: USAID, NIH, Gates Foundation, CDC, and others• Collaborators: South African National Department of Health,
Right to Care, City of Johannesburg, and others