Transcript Cost-Effectiveness of the Type I Boston Keratoprosthesis

Cost-Effectiveness of the
Type II Boston Keratoprosthesis
Jared D. Ament, MD, MPH, Tomasz P. Stryjewski, BS,
Siddharth Pujari, PhD, George Papaliodus, MD,
James Chodosh, MD, MPH, Claes H. Dolman, MD, PhD
Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
FINANCIAL DISCLOSURE: Some of the authors of this poster have received
research funding and travel expense reimbursement from Dr. Dohlman’s
Keratoprosthesis research fund. Dr. Dohlman nor do any of the authors
receive any financial benefit from the sale of the Boston Keratoprosthesis.
Cost-Effectiveness of the Type II Boston Keratoprosthesis
PURPOSE:
A 2009 study1 confirmed the cost-effectiveness (CE) of the
type I Boston Keratoprosthesis (KPro); however, no studies
exist in patient populations with the worst prognoses –
autoimmune diseases and chemical burns. The type II KPro
has been used in these difficult patients with varying
degrees of success. We sought to determine the CE of the
Boston Keratoprosthesis.
Cost-Effectiveness of the Type II Boston Keratoprosthesis
METHODS:
In a retrospective chart review, patients at the Massachusetts
Eye and Ear Infirmary, who underwent KPro type II surgery over
the last 10 years, were identified. Patients had to have a
minimum of 5 year of visual acuity follow-up data recorded. In
this study, patients with autoimmune diseases and chemical
burns represented the majority of our sample. Eleven patients
were included. CE was determined by cost-utility analysis (CUA).
Complications and additional procedures were incorporated
into a weighted cost decision tree. Retention was calculated as
72.7% was assumed at 5 years. Visual acuity values were
converted to utilities and determined to be normally distributed
per Shapiro-Wilk testing.
Cost-Effectiveness of the Type II Boston Keratoprosthesis
RESULTS:
Median preoperative best-corrected visual acuity in the treated eye was
logMAR 2.30.7 (Snellen equivalent HM). Five years post-operatively, the
median best-corrected visual acuity increased to logMar 1.301.17
(Snellen equivalent of 20/400). A total discounted incremental QALY gain
of 0.668 was obtained for the type II keratoprosthesis. This correlates
with a conferred QALY gain (or improvement in quality of life) of 8.7% for
the average patient. The total discounted cost associated with this utility
equaled $42,215. Using the current parameters, the cost-utility of the
KPro from third-party insurer (Medicare) perspective was 63,196
$/QALY. The univariate sensitivity analysis resulted in a range of
incremental cost-effectiveness ratios from 52,078 – 83,871 $/QALY.
Cost-Effectiveness of the Type II Boston Keratoprosthesis
DISCUSSION:
The type II KPro is not yet an established procedure in the US for
complex ophthalmic patients, often because the proposed population has
significant autoimmune disease. This represents an exceedingly difficult
and recalcitrant patient population with significant comorbidities.
Patients have either already failed multiple corneal transplantation or are
not candidates for keratoplasty.
Cost-Effectiveness of the Type II Boston Keratoprosthesis
DISCUSSION:
A sub-analysis of 16 patients with only 2-years of follow-up revealed an
average improvement in visual acuity from HM vision to 20/70. The
average incremental utility increase for this cohort was exceedingly high
at 0.278. This, when compared to a 0.177 average incremental utility
increase in our 5 year cohort, represents a 57% increase in average
utility change. Reassessing 2-year costs and conducting the appropriate
cost-utility calculations yield a cost-effective value of 31,719 $/QALY for
this 2-year sample. The cost effectiveness of type II KPro in this study
was determined to be 63,196 $/QALY. These markedly disparate values
illustrate that a dramatic change occurs in the type II KPro population
after the 2-year postoperative period.
Cost-Effectiveness of the Type II Boston Keratoprosthesis
DISCUSSION:
Although more costly than type I, the intrinsic utility of this device allows
for the type II KPro to remain a moderately cost-effective medical
intervention.
Cost-Effectiveness of the Type II Boston Keratoprosthesis
REFERENCES:
1) Ament JD, Stryjewski TP, Ciolino JB, Todani A, Chodosh J, Dohlman CH. Cost-Effectiveness of
the Boston Keratoprosthesis. Am J Ophthalmol. 2010 Feb;149(2):221-228
2) Brown MM, Brown GC. How to interpret a healthcare economic analysis. Curr Opin
Ophthalmol 2005;16(3):191-4.