Clinical and epidemiological characteristics of refractory hypertension in renal transplant patients.

Hypertension is common following renal transplantation, affecting up to 80% of recipients. It is generally accepted that hypertension is associated with poor graft survival and reduced life expectancy, contributing to increased cardiovascular risk factors and mortality rates. The prevalence of refractory hypertension among renal transplant patients is unknown; it may be associated with a worse prognosis. The aim of our study was to determine the prevalence of refractory hypertension among 529 stable renal transplant recipients and to describe its clinical and epidemiological features. We divided this population into 4 groups to make comparisons: normotensive (n = 82), controlled hypertension (n = 228), uncontrolled hypertension but not refractory (n = 183), and refractory hypertension (n = 36) as defined by a systolic blood pressure >or= 140 mm Hg and/or a diastolic blood pressure >or= 90 mm Hg among patients treated with 3 or more drugs (1 of them being a diuretic). The proportion of patients with refractory hypertension in our transplant unit was 6.8%. The main characteristics of patients with refractory hypertension versus normotensive patients were: mainly systolic hypertension (152.5 +/- 10.32 vs 121.6 +/- 9.26 mm Hg; P < .012), elderly age (59.47 vs 48.33 years; P < .000), diabetes (36.2% vs 1.2%; P < .000), poorer renal function as measured by glomerular filtration rate (36.15 +/- 20.41 vs 56.12 +/- 15.75 mL/min/1.73 m(2); P < .004), higher 24-hour urinary protein excretion (2.55 +/- 2.61 vs 0.5 +/- 0.8 g; P < .003), and steroid treatment (47.2% vs 23.2%; P < .000). The results of this study may help identify the clinical and epidemiological factors which correlated with refractory hypertension for future interventional applications to reduce the morbidity/mortality among the renal transplant population.

Higher initial tacrolimus blood levels and concentration-dose ratios in kidney transplant recipients who develop diabetes mellitus.

Posttransplantation diabetes mellitus (PTDM) is a common complication of kidney transplantation, associated with poorer graft and patient outcomes. Tacrolimus is a strong immunosuppressive drug associated with low acute rejection rates, but a higher risk for PTDM. High trough levels of tacrolimus during the first month after transplantation have been found to be a significant risk factor for the development of PTDM. The aim of this single-center study was to identify the risk factors for the development of PTDM among kidney transplant recipients under tacrolimus therapy. We examined 73 cadaveric kidney transplant recipients receiving tacrolimus between 1994 and 2003. Age, donor and recipient gender, dialysis method, body mass index (BMI), first year weight gain, mismatches, incidence of acute rejection and delayed graft function, hepatitis C serology, first year cumulative steroid dose, first tacrolimus blood level, first tacrolimus blood level <15 ng/mL, and corresponding tacrolimus daily doses and concentration/dose ratios (CDR) were also collected. PTDM was defined as at least 2 fasting blood glucose values > or =126 mg/dL, according to the World Health Organization criteria. Incidence of first year PTDM was 27.4%. Patients with PTDM showed significantly higher age, BMI, first tacrolimus blood level, first tacrolimus CDR, and CDR with tacrolimus blood level <15 ng/mL as well as less 1-year weight gain. After logistic regression, age (relative risk [RR] 1.060, confidence interval [CI] 95%, 1.001-1.122; P = .043) and first tacrolimus blood level (RR 1.154; CI 95%, 1.038-1.283; P = .008) remain significant risk factors for developing PTDM. Older age and initial tacrolimus blood levels were the main risk factors for PTDM among our group of patients. Kidney transplant recipients who develop PTDM maintain a high CDR of tacrolimus.