Health Economic EvaluationWhole exome sequencing in clinical practice

K.J.M. van Nimwegen, MSc.

WES in clinical practice

• Increased diagnostic yield• Currently: 6%• WES: ≥ 22%

• Implement WES in clinical practice based on these data?

• Implications of increased diagnostic yield?• Patients• Parents• Society

• Health economic evaluation

Why do we need economic evaluation in health care?• Increased health care expenditure• Innovative medical technologies are a

major cost driver

• Every euro can only be spent once

• How do we get the biggest health benefit for our money?

Health economic evaluation (I)

Choice

Comparator

Medical intervention

CostsA

CostsB

ConsequencesA

ConsequencesB

ΔCost?ΔEffect?

Which alternative results in the highest value for money?

• Comparative analysis of alternative courses of action in terms of costs and consequences

Health economic evaluation (II)ΔCost

ΔEffect

?

?More costly, less effective

Less costly, more effective

More costly, more effective

Less costly, less effective

Willingness to pay ratio

Methods (I) Costs• 50 patients included

• Retrospective study

• Health care resource use for diagnostic purposes in the Radboud umc• Hospital visits• Inpatient and outpatient stays• Diagnostic tests

• Associated costs

Results (I) Costs

van Nimwegen, K.J.M. et al. The diagnostic pathway in complex paediatric neurology: A cost analysis. European Journal of Paediatric Neurology , 2014. 19(2): p. 233-9

• n = 50• Mean costs of current diagnostic trajectory: €12,475 per patient• Genetic tests account for 43% of the costs (€5,321)

25%

7%

3%43%

22%

Healthcare resource costs

Physician contactsImaging testsNeurophysiologic testsGenetic testsOther diagnostic tests

Results (II) Impact on society

ΔCost

ΔEffect

??

Whole exome sequencing

Current trajectory WES

Costs €12,475 €3,600

* Select population of complex cases

Diagnostic yield 6% ≥ 22%

Impact on patients and their parents• HRQoL

• Impact of receiving a diagnosis on health-related quality of life (HRQoL)?• Patients• Parents

• Quantifying HRQoL• General HRQoL• 1 = perfect health• 0 = dead

• Comparisons between disease areas

General HRQoL

Mental HRQoL

Physical HRQoL

Methods (III) Burden of disease• 100 patients and their parents included

• HRQoL is prospectively and quantitatively measured with the SF-12• Physical HRQoL• Mental HRQoL • Before diagnosis• After diagnosis

• SF-6D scores• General HRQoL

Results (III) HRQoL before diagnosis

Patient Parent0

10

20

30

40

50

60

Physical HRQoLAverage physical HRQoLMental HRQoLAverage mental HRQoL

***

** **

* Significant at p < 0.05** Significant at P < 0.01

Results (IV) HRQoL before diagnosis

**

HRQoLAverage HRQoL

Results (V) ΔCost

ΔEffect

?

?Whole exome sequencing*

* For this patient population

Conclusion• The current diagnostic trajectory is extensive, imposing a burden on the

patients, their parents and, with an average cost of €12,475, on society at large.

• The implementation of WES is expected to lower the costs of this diagnostic trajectory considerably, by substituting expensive low-yield conventional diagnostic tests.

• An increase in diagnostic yield is also to be expected in this patient population. However, the effect of WES on HRQoL, quantitatively measured, is currently under research.

Questions