At our center, since 1982, a body mass index (BMI) of less than 30 has
been a prerequisite for placing a patient on the waiting list for ren
al transplantation. This decision was made because obese transplant re
cipients seemed to have a less than favorable post-transplant outcome.
The aim of this study was to evaluate whether this requirement is sti
ll justified. Forty-six patients with a BMI above 30 underwent primary
cadaveric renal transplantation between 1972 and 1993. For each of th
ese obese patients, five consecutive nonobese (BMI 20-25) control pati
ents were selected. Patient and graft survival, causes of graft loss,
and acute rejection rate were evaluated for the two patient groups bef
ore and after the year 1982. Within the first 30 post-transplant days,
one patient (2 %) and 11 grafts (24 %) were lost in the group of obes
e patients whereas seven patients (3 %) and 36 grafts (16 %) were lost
in the control group. Among the obese patients, renal circulatory com
plications were a major cause of graft loss. In the period 1973-1981,
the 1-year patient survival rate was 65 % among obese patients versus
75 % among controls from 1982 to 1993, this was 90 % versus 93 %. From
1973 to 1981, the 1-year graft survival rate was 25 % among obese pat
ients versus 53 % among controls (P < 0.05); from 1982 to 1993, it was
68 % versus 84 % (P = NS). Multivariate analysis showed that the immu
nosuppressive regimen, age of the patient, BMI, and cold ischemia time
of the graft had a significant influence on graft survival. The acute
rejection rate within the first 30 days was 28 % among obese patients
and 35 % among controls (P = NS). We conclude that a BMI below or equ
al to 30 is still justified as a prerequisite for placement on the wai
ting list for renal transplantation, for despite an overall improvemen
t, the outcome of renal transplantation in obese patients remains wors
e than that in non-obese patients.