Stroke in renal transplant recipients: epidemiology,predictive risk factors and outcome

BACKGROUND: Cerebrovascular and cardiovascular diseases are the most important causes of increased morbidity and mortality in patients with end-stage renal disease. Stroke has been widely reported in chronic dialysis patients, but there is scarce information about stroke in renal transplant recipients (RTR), although cerebrovascular events are the most common and potentially life-threatening neurological complications in them. Our aim is to analyze the prevalence, risk factors, etiopathogenia, clinical aspects and outcome of stroke in RTR. METHODS: We analyzed 403 patients who received one or more renal grafts between 1979 and 2000: group A = patients who had stroke (n = 19); group B = those who did not (n = 384). Medical records and pertinent data were compiled. The risk of stroke was studied using univariate and multivariate Cox regression models. RESULTS: prevalence of stroke in RTR was 7.97% at 10 yr. Time elapsed between renal transplantation (RT) and stroke: 49.3 months. Possible risk factors based on the univariate analyses were: diabetic nephropathy (DN) (p < 0.001) and autosomal-dominant-polycystic-kidney-disease (p = 0.049) as original nephropathies, peripheral vascular disease (PVD) (p < 0.001), diabetes mellitus prior to RT (p = 0.005), age older than 40 yr (p = 0.037) and hypertension (p = 0.049). Other analysed risk factors such as gender, renal function, cytomegalovirus infection, hyperlipidemia, hyperuricemia, erythrocytosis or hypertensive donor failed to show any significant predictive value for stroke in these patients. When multivariate analyses were carried out, we found that DN (OR = 4.8; p = 0.010), PVD (OR = 8.2; p < 0.001) and age > 40 yr (OR = 3.3; p = 0.019) were predictive risk factors for stroke. For group A, hypertension was present in all patients, 68.4% had hyperlipidemia and 42.1% reported previous stroke. Cerebral hemorrhage occurred in seven of 19 (36.84%) of the stroke patients, but no subarachnoid hemorrhage occurred in them. Seven of 12 ischemic strokes were atherotrombotic. Considering all strokes, basal ganglia was the predominant localization. The outcome was poor, as nearly half of the patients died in the 3 months following stroke. CONCLUSIONS: Prevalence of stroke in our RTR population was 7.97%. Cerebral hemorrhage appears to be more prevalent in RTR than in general population. More than that, the cerebral hemorrhage rate we found is higher than that reported elsewhere in RTR. The main predictors of stroke were DN, PVD and age. No patient with interstitial nephropathy suffered stroke. Mortality is high in RTR with stroke.