Strokes Raise Death Risk in Dialysis Patients
Risk of dying after suffering a hemorrhagic or ischemic stroke is greatest in the first week.
James B. Wetmore, MD, of Hennepin County Medical Center in Minneapolis, Minn., and colleagues analyzed a cohort of 69,371 individuals with a mean age 60.8 years.
After entry into the cohort, the group experienced 21.1 ischemic strokes and 4.7 hemorrhagic strokes per 1,000 patient-years. At 30 days, mortality was 17.9% for ischemic stroke and 53.45 for hemorrhagic stroke, the investigators reported online ahead of print in the Clinical Journal of the American Society of Nephrology.
In adjusted analyses, patients who had a hemorrhagic stroke at 1 year after cohort entry had a 25 times increased risk of death at 1 week and a 9.9 times, 5.9-times, and 1.8 times increased risk of death at 3, 6, and 24 months, respectively, compared with patients who did not suffer a stroke. Patients with ischemic stroke at 1 year after cohort entry had an 11.7 times, 6.6 times, and 4.7 times increased risk of death at 1 week and 3 and 6 months, respectively. Their risk of death remained significantly elevated even at 48 months, according to the investigators.
In addition, the median months of life lost were 40.7 for hemorrhagic stroke sufferers and 34.6 months for ischemic stroke sufferers. Mortality did not differ by race, regardless of stroke type.
The study demonstrated an overall stroke incidence rate of 25.8 new events per 1,000 patient-years, which the researchers observed is in the middle of the range found in other studies of dialysis patients.
In a study published recently in the American Journal of Kidney Diseases (2014;63:604-611), researchers in Taiwan found that the incidence of hospitalization for ischemic stroke was 102.6 and 100.1 per 10,000 person-years in patients on hemodialysis (HD) and peritoneal dialysis (PD), respectively.
The incidence of hemorrhagic stroke was 74.7 and 59.4 per 10,000 person-years, respectively. In multivariate analysis, HD and PD were associated with a 2.88 and 3.21 times increased risk of ischemic stroke, respectively, and a 6.83 and 6.15 times increased risk of hemorrhagic stroke, respectively, compared with age- and gender-matched individuals in the general population.
The reasons why stroke may affect mortality remains uncertain, Dr. Wetmore's group commented. “Stroke is part of an epiphenomenon involving inflammation, nutrition, and frailty,” Dr. Wetmore's team wrote. “Individuals with a substantial inflammatory burden or a high degree of frailty are at increased risk for both stroke and death.
Alternately, it is also plausible that a disabling stroke might adversely affect functional status and nutrition, leading to frailty and premature death.”