The impact of socioeconomic factors on long-term outcome after renal transplantation is unknown. We examined the effects of family income among 202 patients transplanted between 1976 and 1982 who had an allograft that functioned for at least 1 year. Compared with patients with an adequate income, recipients of medical assistance at the time of transplantation were more likely to return to dialysis after 1 year (16/45 [36%] v 26/157 [17%], P < 0.01), or after 5 years of graft function (10/38 [26%] v 12/116 [10%], P < 0.01). Patients who complied with fewer than 85% of visits during the first 2 years were also more likely to return to dialysis after 1 year (17/49 [35%] v 25/153 [16%], P < 0.01), or after 5 years (8/31 [26%] v 14/123 [11%], P < 0.05) than were more compliant patients. However, noncompliance was not different in patients with and without a low income (37/157 [24%] v 12/45 [27%], P > 0.05). The relative risk for returning to dialysis after 5 years was 2.4 (P < 0.05) for low income and 3.0 (P < 0.05) for less than 85% compliance using a Cox proportional hazards model. These effects were independent of prior transplantation, mismatches, pre-formed antibodies, delayed graft function, age, sex, diabetes, alcohol or drug abuse, education, race, distance from the transplant center, and living in an urban environment (relative risk = 2.5, P < 0.05). Neither income nor compliance could be linked to death. Thus, income level affects long-term graft survival by mechanisms that are independent of compliance with clinic visits and other known risk-factors.
- graft survival