Strokes in patients on haemodialysis: incidence, onset time and associated factors

The incidence of stroke is higher substantially among hemodialysis patients than in the overall population. In this observational cohort study, we analysed data from incident hemodialysis patients at Valdecilla University Hospital in Santander (Spain) during a 40-year period (1971-2011). A total number of 1453 patients were started on hemodialysis The total follow-up period was 4982.22 patients/year, with 84 patients having stroke. The cumulative incidence of stroke in our patients was 5.8%, with an incidence rate of 1686 strokes per 100 000 patient-years. The incidence rate in the first year was 1803 strokes per 100 000 patients-year, 6.5% higher than its average over the period studied. In the remaining period, the rates ranged between 356 and 1626 strokes per 100 000 patients-year. Significative factors related to stroke were: diabetes, myocardial infarction or angina, hypertension, arteriosclerosis/intermittent claudication, history of stroke before the HD and atrial fibrillation. Haemoglobin levels in the cohort stroke were virtually identical to those of the not stroke cohort (11.92 +/- 2.07g/dL, compared to 11, 68 +/- 2.12g/dL). Finally, 60.7% of the population of the stroke cohort received erythropoietin with mean dose of 9611lU/week, compared to 51.9% and a dose of 9544lU/week in the not stroke cohort, without significative differences among groups. In conclusion, in haemodialysis population the incidence of stroke is 7-10 times higher than in the general population. It is associated with well known factors for stroke but not with haemoglobin levels or erythropoietin dose.