[Systemic hypertension after kidney transplantation: associated risk factors and influence on graft survival]

Systemic hypertension after kidney transplant (HAPT) has been associated with a reduction in graft survival and increased morbidity and mortality of kidney transplant recipients. With the use of calcinuerin inhibitors, prevalence of HAPT has increased to 60-80%. The purpose of this study was to document the prevalence of HAPT in kidney transplant recipients attending the Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán" associated risk factors and the effect of hypertension in long term graft survival. We retrospectively reviewed the clinical charts of all the patients that underwent kidney transplant from 1984 to 1994. The following risk factors were studied: age, gender, cause of renal failure, presence of hypertension before kidney transplant, histocompatibility, acute rejection episodes, chronic rejection, serum creatinine values and use of cyclosporine. We divided subjects in two groups: normotensive (NT) and hypertensive (HT). HAPT included 3140/90 mmHg blood pressure level observed at least during two consecutive evaluations or the use of antihypertensive medication. We analyzed 215 grafts from 205 patients (10 patients had two kidney transplants); mean age at transplant of 30 +/- 9 years, 131 subjects were female and 84 male. One hundred and eighty eight patients (88%) displayed pretransplant hypertension. The mean follow up was 56+/-32 months. In the postransplant period 152 (71%) were HT and 63 (29%) NT. The HT group had significantly higher blood pressure and serum creatinine values than the NT group (P < 0.001), in spite of an adequate blood pressure control in 65% of the patients from the HT group. The NT group displayed a higher graft survival than the HT group; 60 +/- 30 months vs. 51 +/- 32 months respectively (p<0.01). Multivariate analysis did not show any risk factors independently associated with the development of HAPT. The prevalence of HAPT in our series is similar to the one reported in the literature. During the postransplant period there was a reduction of hypertensive patients (88% pretransplant vs. 71% postransplant). HAPT is a significant risk factor associated with long term survival of the graft.