Cost-effectiveness of Descemet's stripping endothelial keratoplasty versus penetrating keratoplasty

Purpose: Selective endothelial transplantation in the form of Descemet's stripping endothelial keratoplasty (DSEK) is rapidly replacing traditional full-thickness penetrating keratoplasty (PK) for endothelial disease. An incremental cost-effectiveness analysis was performed to determine whether the benefits of DSEK are worth the additional costs.

Design: Retrospective cohort study.

Participants: Patients at the Singapore National Eye Center, a tertiary eye center in Singapore, with Fuchs' dystrophy or bullous keratopathy who underwent either PK or DSEK.

Intervention: Patients underwent either PK (n = 171) or DSEK (n = 93) from January 2001 through December 2007. Data were collected from inpatient and outpatient notes corresponding to the time immediately before the procedure to up to 3 years after.

Main outcome measures: Improvements in best spectacle-corrected visual acuity were used to calculate the increase in quality-adjusted life years (QALYs) 3 years after the procedure. This was combined with hospital charges (a proxy for costs) to determine incremental cost-effectiveness ratios (ICERs) comparing PK with no intervention and DSEK with PK.

Results: Three-year charges for DSEK and PK were $7476 and $7236, respectively. The regression-adjusted improvement in visual acuity for PK relative to no intervention was -0.613 logarithm of the minimum angle of resolution (logMAR) units (P<0.001), and for DSEK relative to PK, it was -0.199 logMAR units (P = 0.045). The regression-adjusted marginal gain in utility for PK relative to no intervention was 0.128 QALYs (P<0.001) and for DSEK relative to PK was 0.046 QALYs (P = 0.031). This resulted in ICERs of $56 409 per QALY for PK relative to no intervention and $5209 per QALY for the more expensive DSEK relative to PK.

Conclusions: If the goal is to maximize societal health gains given fixed resources, DSEK should be the preferred strategy. For a fixed budget, it is possible to achieve greater QALY gains by providing DSEK to as many patients as possible (and nothing to others), rather than providing PK.