Baseline blood pressure and other variables influencing survival on haemodialysis of patients without overt cardiovascular disease

Background. Age, diabetes and concomitant cardiovascular disease, recorded at the initiation of dialysis, allows the identification of patients with a high probability of eat-ly mortality. When all of these factors are taken into account the mortality rate of dialysis patients is still 3.5 times higher than for the general population. Information on the factors that increase the mortality of patients lacking the major cardiovascular risk factors is important because these are likely to be correctable, especially if detected early. Methods. We investigated prospectively the relevance of blood pressure and other variables recorded at the initiation of dialysis treatment on the survival of a group of 103 relatively young adult haemodialysis patients (mean age 44.3 years +/- 13 SD), with a low prevalence of comorbidity and a median follow-up period of 79 months. Data were analysed by the Cox proportional regression model and survival curves were constructed by the Kaplan-Meier method. Results. Forty-four patients died, 20 (46%) of whom as a result of cardiovascular causes. Multivariate analysis showed that mortality was associated with age (P = 0.0001), serum creatinine (P = 0.005, negative association), left ventricular (LV) mass (P = 0.003) and hypertension (P = 0.03). Mortality was increased by 7% for each additional year of age, by 0.7% for each 1 g increase in LV mass, and was reduced by 23% for each additional mg/dl of serum creatinine. Hypertensive patients had a higher probability (x 2.2) of dying compared with normotensive patients. Conclusions. In addition to age and conditions of occult malnutrition, hypertension and LV hypertrophy, when present at the initiation of dialysis, play a major role in the mortality of low risk, relatively young dialysis patients. These potentially correctable factors should be actively sought and treated during the early stage of renal insufficiency to improve prognosis.