Longitudinal Changes in the Impact of Socioeconomic Status on Graft Failure in Kidney Transplantation.

KEY POINTS: Employment status and insurance type consistently affected graft survival in KT, whereas the influence of education level varied over time post-transplant. The area deprivation index was linked to graft failure in KT from the early to the long-term post-transplantation period. Follow-up strategies to optimize long-term KT outcomes should address socioeconomic factors at both individual and area levels.

BACKGROUND

Socioeconomic status is recognized as a factor influencing graft survival in adult kidney transplantation (KT). However, limited research has examined whether socioeconomic factors influence transplant outcomes differently across post-transplantation periods. We evaluated the longitudinal impact of socioeconomic factors on graft failure post-KT over time.

METHODS

Adult KT alone performed from 2003 to 2013 were evaluated using the Organ Procurement and Transplantation Network database. The period of post-transplantation was divided into three categories, and the outcome of each group is as follows; group 1: graft failure within 1 year in all patients, group 2: graft failure within 5 years in 1-year graft survivors, and group 3: graft failure within 10 years in 5-year graft survivors. We explored the influence of socioeconomic factors on outcomes in living donor kidney transplantation (LDKT) and deceased donor kidney transplantation (DDKT), separately. Socioeconomic factors included patient education level, employment status at transplantation, insurance status, and area deprivation index (ADI). Higher ADI scores represent greater socioeconomic deprivation.

RESULTS

In total, 153,660 adult KT were performed from 2003 to 2013 (group 1), of which 140,699 recipients survived at 1 year (group 2) and 106,238 recipients survived at 5 years (group 3) post-transplantation. While employment status and insurance status consistently influenced graft failure over time, the impact of education level was time-dependent. High school education was associated with a high risk of graft failure, compared with post-college education only in the later post-transplantation periods (group 3) for both DDKT (hazard ratio, 1.09; P = 0.025) and LDKT (hazard ratio, 1.26; P < 0.001), but not in the early period (group 1). ADI-based analysis showed that recipients from highly deprived areas had worse post-transplantation outcomes across all periods in both DDKT and LDKT.

CONCLUSIONS

The impact of individual-level socioeconomic factors on post-KT outcomes varied over time. Socioeconomically disadvantaged patients had an increased risk of graft failure from the early to the long-term post-KT period. To optimize long-term outcomes, follow-up strategies should incorporate both individual-level and area-level socioeconomic factors.