Objective: To investigate whether the correlation of age and sex with
the risk of recurrence and death seen in patients with previous ischemic
stroke is also evident in patients with embolic stroke of undetermined
source (ESUS).
Methods: We pooled datasets of 11 stroke registries from Europe and
America. ESUS was defined according to the Cryptogenic Stroke/ESUS
InternationalWorking Group. We performed Cox regression and Kaplan-Meier
product limit analyses to investigate whether age (<60, 60-80, >80
years) and sex were independently associated with the risk for ischemic
stroke/TIA recurrence or death.
Results: Ischemic stroke/TIA recurrences and deaths per 100
patient-years were 2.46 and 1.01 in patients <60 years old, 5.76 and
5.23 in patients 60 to 80 years old, 7.88 and 11.58 in those.80 years
old, 3.53 and 3.48 in women, and 4.49 and 3.98 in men, respectively.
Female sex was not associated with increased risk for recurrent ischemic
stroke/TIA (hazard ratio [HR] 1.15, 95% confidence interval [CI]
0.84-1.58) or death (HR 1.35, 95% CI 0.97-1.86). Compared with the
group <60 years old, the 60-to 80-and >80-year groups had higher 10-year
cumulative probability of recurrent ischemic stroke/TIA (14.0%, 47.9%,
and 37.0%, respectively, p, 0.001) and death (6.4%, 40.6%, and 100%,
respectively, p, 0.001) and higher risk for recurrent ischemic
stroke/TIA (HR 1.90, 95% CI 1.21-2.98 and HR 2.71, 95% CI 1.57-4.70,
respectively) and death (HR 4.43, 95% CI 2.32-8.44 and HR 8.01, 95% CI
3.98-16.10, respectively).
Conclusions: Age, but not sex, is a strong predictor of stroke
recurrence and death in ESUS. The risk is approximate to 3-and 8-fold
higher in patients >80 years compared with those <[60 years of age,
respectively. The age distribution in the ongoing ESUS trials may
potentially influence their power to detect a significant treatment
association