Donor age and corneal endothelial cell loss 5 years after successful corneal transplantation. Specular microscopy ancillary study results.

OBJECTIVE: To determine whether endothelial cell loss 5 years after successful corneal transplantation is related to the age of the donor.
DESIGN: Multicenter, prospective, double-masked clinical trial. PARTICIPANTS: Three hundred forty-seven subjects participating in the Cornea Donor Study who had not experienced graft failure 5 years after corneal transplantation for a moderate-risk condition (principally Fuchs' dystrophy or pseudophakic corneal edema). TESTING: Specular microscopic images of donor corneas obtained before surgery and postoperatively at 6 months, 12 months, and then annually through 5 years were submitted to a central reading center to measure endothelial cell density (ECD). MAIN OUTCOME MEASURE: Endothelial cell density at 5 years.
RESULTS: At 5 years, there was a substantial decrease in ECD from baseline for all donor ages. Subjects who received a cornea from a donor 12 to 65 years old experienced a median cell loss of 69% in the study eye, resulting in a 5-year median ECD of 824 cells/mm(2) (interquartile range, 613-1342), whereas subjects who received a cornea from a donor 66 to 75 years old experienced a cell loss of 75%, resulting in a median 5-year ECD of 654 cells/mm(2) (interquartile range, 538-986) (P [adjusted for baseline ECD] = 0.04). Statistically, there was a weak negative association between ECD and donor age analyzed as a continuous variable (r [adjusted for baseline ECD] = -0.19; 95% confidence interval, -0.29 to -0.08).
CONCLUSIONS: Endothelial cell loss is substantial in the 5 years after corneal transplantation. There is a slight association between cell loss and donor age. This finding emphasizes the importance of longer-term follow-up of this cohort to determine if this relationship affects graft survival.