Screening for transient ischemic attacks in hemodialysis patients

Rapid recognition and management of transient ischemic attacks (TIAs) reduce incident strokes in the general population, but similar data are lacking in dialysis patients, who form a high-risk group for this pathology. We systematically screened hemodialysis patients for TIA to estimate its incidence and determine whether there was significant scope to reduce subsequent strokes by risk modification.

Patients established on hemodialysis at a satellite dialysis unit at our center were screened prospectively using weekly symptom questionnaires over a 12-month period. Following clinical review, patients who screened positive were urgently referred to a TIA clinic, and all stroke and TIA and stroke events were recorded.

A total of 304 patients were screened over 2,594 total patient months of follow-up (1st November 2009 to 1st November 2010). Six strokes occurred, of which 5 were ischemic (a rate of 23.1/1,000 patient-years). No patients screened positive for a TIA, despite predicted rates of 4.2/1,000 patient-years (95% confidence interval, 1.4-9.7/1,000 patient-years). One ischemic stroke was preceded by symptoms compatible with a TIA, although this was ascertained in retrospect and not during screening.

Based on the first study of its kind to date, systematic screening for TIA has a low yield and cannot be relied on alone to identify patients at higher risk of cerebrovascular events. The confounding presence of symptoms attributable to uremia, neuropathy, hypotension and dysglycemia could reduce the sensitivity of established tests, with significant implications for the detection and treatment of TIA in dialysis.