RESULTS
Of the 233 patients included in the study, 164 were male (70.0%). The mean age was 42.8 ± 11.6 (17-76). Demographic features of the patients were shown in table 1. At follow up period, serum uric acid levels and glomerular filtration rate of patients were shown in table 2.
According to uric acid level at the end of the second year, there was graft loss in 9 patients (7.5 %) of G2 (n=120) and in 18 patients (15.9%) of G1. For first 2 year graft loss was found to be significantly higher in G1 than G2 (p = 0.045). According to allopurinol therapy 10 of the graft loss occurred in the G1-A+ and 8 in the G1 A-, and there was no difference between them (p = 0.330).
In 5. year among G5 (118 patients), graft loss occurred in 12 (21%) of G5-1 (n = 56), while graft loss occurred in 9 (14%) G5-2 (n = 62). There was no statistical difference between these two group (p = 0.62). Graft loss occurred in 7 (23 %) of G5-1 A+ (30 patients) and in 5 (19%) of G5-1A- (26 patients), and there was no significant difference between these two groups (p: 0.71).
However, in G5-1 (56 patients) (n = 118), 8 graft losses developed in the first two years, and 4 graft losses occurred between 2 and 5 years. Meanwhile, in the group with normal SUA (n = 62), there were 2 graft losses in the first two years and 7 graft losses between 2 and 5 years. (Table 3)
Considering the first two years in patients followed for five years; In G5-1 the loss of grafts was significantly higher than in the G5-2 (p = 0.023), and higher SUA levels increased the graft loss by 3.6 times compared to normal SUA levels (95% confidence interval: 1,2-12.70).
Comparing to baseline GFR decreased in both hyperuricemic group (G1) and normouricemic group (G2) followed for 2 years (p<0.001), and the decline was the same in both groups (p = 0.691) (figure1). There was also a change in GFR in both G1A + and G1A + groups (p = 0.043) and this change was significant in favor of allopurinol patients (p <0.001) (figure 2).
In correlation analysis, eGFR values were decreased in both groups with high uric acid (n = 56) (G5-1) and normal uric acid (n: 62) (G5-2) during 5 years follow up (p: <0.001) However the decrements were found to be similar in both groups (p = 0.818) (Figure 3)
Comparing to baseline eGFR values according to allopurinol therapy during 5 year follow up in kidney transplant recipients decreased significantly (p: 0.001). The decrements of eGFR were also significantly different according to with or without allopurinol treatment (p: 0.034). As seen in figure 4 in patients treated with allopurinol GFR increased in the first two years. Although GFR begins to decrease after the second year, the protective effect of GFR was significant and 5 years of follow-up was still effective to cause for difference of 20 mL/min (figure 4).