To determine the prevalence of left ventricular hypertrophy (LVH; left ventricular wall thickness greater than or equal to 1-2 cm in diastole) among end-stage renal disease (ESRD) patients and the most important risk factors that independently relate to LVH, 189 non-diabetic ESRD patients without dilated cardiomyopathy in two centres had echocardiography and full clinical review. 104 of 189 (55%) patients had LVH consisting of 52 of 83 (65%) patients on haemodialysis, 18 of 20 (90%) peritoneal dialysis patients and 34 of 86 (40%) transplanted patients. Using multiple logistic regression, the most important factors which independently related to LVH, in all patients studied, were dialysis as current ESRD treatment (p less than 0.001), followed by age (p = 0.008), hypertension as defined by number of blood pressure medications (p = 0.007), followed by high serum alkaline phosphatase which probably reflects hyperparathyroidism (p = 0.03). In a subset of patients with severe LVH (left ventricular wall thickness greater than or equal to 1.4 cm), a high serum alkaline phosphatase level was the best predictor of LVH (p less than 0.001), followed by high diastolic blood pressure (p = 0.004) and age (p = 0.02). In dialysis patients, the most important variable were age (p = 0.009) and high serum alkaline phosphatase (p = 0.03). In the transplant group, patients with LVH were taking significantly more antihypertensive medications than those without LVH (p = 0.002). This variable was the only predictor of LVH in the transplant group.(ABSTRACT TRUNCATED AT 250 WORDS)