CARDIAC REVASCULARIZATION SURGERY IN THE ELDERLY: AN EVIDENCE-BASED HEALTH ECONOMIC APPROACH    Background: Increasing prevalence of chronic disease in the context of an ageing society has led many to question the value of cardiac revascularization surgery and associated intensive care in elderly (octogenarian) populations. However societal expectations of improved technology and its likely impact on longevity and improved quality of life suggest there is a demand for cardiac surgery in this population. Elderly people are more likely to hold private health insurance, therefore the cost (in terms of waiting time) is likely to be low.     Objectives: This presentation will consider the value of cardiac revascularization surgery from a health economic perspective, including the various perspectives of patient, family/significant others, providers, healthcare sector and society.     Method: A theoretical evidence-based health economic model will be presented that is relevant to the evaluation of cardiac surgery in an elderly population. This will be combined with a review of the literature and existing data sources as evidence-based inputs into the development of an economic model to assess cost effectiveness in terms of cost per quality adjusted life year saved. Studies included will be recent published trials (post 2010) where costs and/or quality of life outcomes have been compared between cardiac surgery and conservative management in an elderly (80+ years) population.     Results/Conclusion: Recent literature and study results will be reviewed against the theoretical health economic model. Where evidence and/or data exist that meet inclusion criteria for the economic analysis these will be summarised in the model. Where gaps in evidence exist these will be highlighted, including appropriate strategies to address data deficiencies.     A/Prof Jennifer Watts  Health Economics  Faculty of Health   Deakin University 

1. CARDIAC
REVASCULARIZATION
SURGERY IN THE ELDERLY: AN
EVIDENCE-BASED HEALTH
ECONOMIC APPROACH
Jennifer Watts
Associate Professor, Deakin Health Economics
Faculty of Health
Deakin University CRICOS Provider Code: 00113B

2. I declare that I have no conflict of
interest, affiliation or involvement in any
organization or entity with any financial
interest concerning the following
presentation
Jennifer Watts
Associate Professor, Deakin Health Economics
Faculty of Health
Deakin University CRICOS Provider Code: 00113B

3. Background
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• More than 68,000 cardiac procedures in people aged 80+ years in
Australia in 2015/16 (17% total cardiac procedures)
• 28,750 coronary artery procedures in people aged 80+ years
– 14% all coronary artery procedures
– 42% procedures in people aged 80+years
• Of the 28,750 CAPs in 80+ years:
– 19,500 (68%) were angiography
– 5,700 (20%) were angioplasty with stent
– 2,450 (8.5%) were CABGs
Source: AIHW, 2018

4. Background
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• Evidence of effectiveness/cost effectiveness of
revascularization procedures in octogenarians?
• Most clinical trials exclude elderly people and, if included,
are not powered to do sub-group analysis
– For economic evaluation comparison should be with
equivalent population
– Gelosomino et al 2011 compared 80+ with 70-79 years
• Rapidly changing clinical environment (technologies,
procedures, anaesthesia)

5. Objective
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To consider the value of cardiac
revascularization surgery from a health
economic perspective, including the various
perspectives of patient, healthcare system
and society

6. Economic evaluation question
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Is cardiac revascularisation surgery cost effective
in the population with coronary artery disease
aged 80 years and older compared to
conservative management in terms of health
related quality of life over a 5 year period from a
health system/societal perspective?

7. Method
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• Theoretical decision analysis model for economic evaluation
of cardiac revascularisation procedures in people aged 80+
years with coronary artery disease (CAD)
• Literature synthesis to determine current data as model
inputs:
– Limited to trials post 2010 (data collected and published post-2010)
– Population: People aged 80+ years with coronary artery disease
– Comparison of conservative management and procedures
(angioplasty, +/- stent, coronary artery bypass graft surgery (CABGs)
• Understand where the “data gaps” are

8. $
$
$
$
Decision analysis
model for CAD
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
$
 Decision node
 Probability node
 Outcome/health state
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL
HRQOL

9. Sources of cost data
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• Patient level costs (hospital costing data + Medicare data)
– Possible to get, data requires permission and ethics approval
– Lag in data collection
• Modelled cost of hospitalisation
– Based on LOS (hospital, CICU, rehab), can use DRG level data but will
not be specific to age
– Could assume mean cost per day and multiply x LOS (older
population)
• Resource use questionnaire for non-hospital care
– include cost of follow-up hospitalisation (readmissions)
– recall

10. DRG level costs for common CAD
procedures
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DRG DRG description
Average Total
Cost (2015-16)
F08A
MJR RECNSTR VASC PR-PUMP,
MAJC
$ 63,095
F08B
MJR RECNSTR VASC PR-PUMP,
INTC
$ 32,820
F10A INTERVENT CRNRY PR + AMI, MAJC $ 20,587
F10B INTERVENT CRNRY PR + AMI, MINC $ 11,194
F15A
INTERV CRNRY PR-AMI+STNT,
MAJC
$ 17,863
F15B INTERV CRNRY PR-AMI+STNT, MINC $ 8,471
Source: AIHW National Hospital Cost Data Collection (public hospitals only), 2015-16 (online resource)

11. Length of stay data for CAD in
population aged 80+years
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DRG
Average length
of stay
Average
length of
stay
%
difference
in ALOS(80+ years) (<80 years)
F05A Coronary Bypass W Invasive Cardiac
Investigation W Catastrophic CC
18.0 16.3 9.8
F05B Coronary Bypass W Invasive Cardiac
Investigation W/O Catastrophic CC
13.0 12.1 7.6
F06A Coronary Bypass W/O Invasive Cardiac
Investigation W Catastrophic CC
13.4 11.2 17.7
F06B Coronary Bypass W/O Invasive Cardiac
Investigation W/O Catastrophic CC
9.9 8.4 16.6
F08A Major Reconstructive Vascular Procedures
W/O CPB Pump W Cat CC
13.8 13.0 6.3
F08B Major Reconstructive Vascular Procedures
W/O CPB Pump W/O Cat CC
5.6 5.0 9.9
DRG
Average length
of stay
Average
length of
stay
%
difference
in ALOS(80+ years) (<80 years)
F10A Interventional Coronary Procedures Admitted
for AMI W Catastrophic CC
8.1 6.9 16.3
F10B Interventional Coronary Procedures Admitted
for AMI W/O Catastrophic CC
3.8 3.2 17.8
F15A Interventional Coronary Procs, Not Adm for
AMI W Stent Implant W Cat/Sev CC
5.3 3.8 33.4
F15B Interventional Coronary Procs, Not Adm for
AMI W Stent Implant W/O Cat/Sev CC
2.0 1.6 23.0
F16A Interventional Coronary Procs, Not Adm for
AMI W/O Stent Implant W CC
4.4 3.5 22.0
F16B Interventional Coronary Procs, Not Adm for
AMI W/O Stent Implant W/O CC
1.9 1.5 18.6
Weighted mean LOS 6.0 5.0 17.8
F09C Other Cardiothoracic Procs W/O CPB Pump,
Died/Trans Acute Facility <5 Days
1.7 1.5 10.8
Source: AIHW National Hospital Cost Data Collection, 2015-16 (online resource)

12. Costing health service utilisation
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• Cost of hospital episode, LOS differences suggest that
total cost may be “high”
– How high depends on where the extension in LOS occurs, cardiac ICU
or “waiting for discharge”?
• Cost of follow-up care
– Comparator is medical management, follow-up for 5 years
subsequent admissions and primary care
– Pattern of resource use is likely to be different
– Incremental cost; difference between groups

13. Measuring Quality of Life
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Health related quality of life (HRQOL) instruments:
• Generic health questionnaires, eg SF36
- comprehensive, can compare across conditions
• Condition specific measures, eg Seattle Angina
Questionnaire (SAQ), Dukes Activity Status Index (DASI)
• Preference-based measures, EQ-5D, HUI, AQOL-4D
- overall impact of treatment on HRQOL

14. Measuring Quality of Life
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Advantages of preference-based measures for economic
evaluation:
• Get a single index measure for HRQOL that is based on
preferences for one health state over another
• Scoring algorithm is population-based, not specific to a disease
but specific to the population, eg “Australian norms”
• Single index measure is used as the denominator in cost
effectiveness studies, for example $/QALY (cost per quality
adjusted life year saved)

15. Sources of HRQOL data for CAD in
population aged 80+years
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Review of the literature
A systematic review published in 2013 specifically looked at QOL in
elderly population (70+ years) following CABGs (Baig et al 2013)
– Literature ranged from 1992 – 2012, 2 studies published post-2010
– Quality generally poor (>50% retrospective; 3/23 (13%) RCTs; most had no baseline
assessment of QOL)
– Range of QOL instruments used, only 6 studies included generic utility instrument
(EQ-5D)
– Follow-up period 3/12 – 36/12
– The 2 studies post-2010 both found an improvement in QOL (EQ-5D) at 6/12
and 12/12 post-CABGS

16. Incremental cost effectiveness ratio
(ICER)
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Incremental cost effectiveness ratio (ICER) is the difference in
costs and effects between two interventions, in this example it
would be:
Benefit(QOL)procedure1 – Benefit(QOL)medical
Cost($)procedure1 – Cost($)medical
ICER is the Cost per Quality Adjusted Life Year Saved

17. Incremental cost effectiveness ratio
(ICER)
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Intervention
costs
Intervention
benefits/effects
Higher cost
More effective
?
Lower cost
More effective

Higher costs
Less effective
X
Lower cost
Less effective
?
More Benefits (+)Less Benefits (-)
Lower costs (-)
Higher Costs (+)
Dominant
Dominated

18. Willingness to pay for a QALY
18
• Australia “generally accepted” that the
PBAC threshold is $50000 per QALY gained
(but not explicit)
• NICE (UK) threshold range of £20,000 to
£30,000 per QALY gained (explicit)
=$35000-$50000AUD

19. Results: Recommendations
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1. Prospective study measuring HRQOL in octogenarian population
– baseline (pre-surgery) with annual follow-up for 5 years (for angioplasty, stent, CABGs)
– Utility instrument (AQOL or EQ-5D or SF-6D + cardiac specific instrument +/- SF36)
2. RCT comparing outcomes in elderly population: procedure vs
medical management
– powered for subgroup analysis
3. Costing study using individual patient level data (hospital episode)
and resource use questionnaire with minimum 12 month follow-up

20. Discussion
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How much is society willing to pay for an improvement in
health related quality of life?
What is a QALY worth?
– Do we weight populations differently?
– Do we have lower weights for older populations?
– Rule of rescue?
Patient perspective: improvements in HRQOL are
important
Resource allocation and priority setting in health system
– What is the opportunity cost?

21. Acknowledgement
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Thankyou to the College of Intensive Care Medicine
for inviting me to present and to my fellow
discussants/panel

22. References
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•Takousi MG, Schmeer S et al, 2016. “Health-related quality of life after coronary revascularization: a systematic review with meta-analysis”,
Hellenic Journal of Cardiology 57: 223-37.
•Gelsomino S, Lorusso R et al 2011 “Cost and effectiveness of cardiac surgery in elderly patients”, J of thoracic and Cardiovascular Surgey, 142:
1062-73.
•Houlind K, Kjeldsen BJ, et al, (2013). “OPCAB surgery is cost-effective for elderly patients”, Scandinavian Cardiovascular Journal, 47: 185-92.
•Keinpell RM, Avitall B et al (2015), “Randomized trial of a discharge planning and telehealth intervention for patients aged 65 an older after
coronary artery bypass graft surgery”, Int J of clinical Cardiology 2:4.
•Speziale G, Nasso G etal (2011), “Short-term and long-term results of cardiac surgery in elderly and very elderly patients”, J of thoracic and
Cardiovascular surgery, 141: 725-31.
•Nicolini F, Agostinaelli A et al, (2014) “The evolution of cardiovascular surgery in elderly patient: a review of current options and outcomes”,
Biomed Research International (open access)
•Bak E, Marcisz C (2014), Quality of life in elderly patients following coronary artery bypass grafting, Patient preference and adherence, 8: 289-
9.
•Cacciatore F, Anello CB et al (2011) Determinants of prolonged intensive care unit stay after cardiac surgery in the elderly, Aging Clin Exp Res
24(6): 627-34.
•Baig K, Harling L et al (2013). Does coronary artery bypass grafting improve quality of life in elderly patients? Interactive Cardiovascular and
Thoracic Surgery 17: 542-53.
•Gjeilo KH, Wahba A et al (2013). Survival and quality of life in an elderly cardiac surgery population: 5-year follow-up”, Eur J Cardio-thoracic
Surg, 44: e182-8.