Background and purpose:
Atherosclerotic stenosis of major intracranial arteries accounts for 5 to 10% of all causes of stroke. The Warfarin versus Aspirin Symptomatic Intracranial Disease (WASID) Study has demonstrated stroke onset in 5 among 100 patients with asymptomatic intracranial arterial stenosis (AIAS) during the follow-up period of 1.8 years. However, there are no prospective studies of intracranial stenosis in healthy subjects with a longer follow-up period. We conducted a 7-years longitudinal study in healthy subjects with AIAS to examine its risk factors and prognosis.
Methods:
We performed a prospective study on 3,155 neurologically normal subjects without history of stroke (1724 men, 1431 woman, mean age of 59). They were followed up with the mean interval of 83 months to obtain information about their stroke event with a questionnaire by mail or telephone interview and inquiry to the relevant medical facilities. AIAS were assessed on MRA at the time of first visit for all subjects.
Result:
AIAS was detected in 323 subjects (10.2%; AIAS group) at the initial examination. Significant risk factors for AIAS were older age, female, hypertension, high values of fasting blood glucose and HbA1c. During the follow-up stroke occurred in 77 subjects (2.7%) from the no-AIAS group and 14 subjects (4.3%) from the AIAS group (p = 0.07). Age and sex affected the stroke onset. The Cox's proportional-Hazards regression model after adjustment of age and sex revealed the significant contribution of AIAS on stroke onset (OR 1.9; 95% CI 1.03-3.4, p = 0.039). The stroke types were 11 ischemic and 3 hemorrhagic in the AIAS group.
Conclusions:
AIAS is a significant risk factor for future stroke even in healthy subjects. Intense management of blood pressure and glucose level might be crucial for preventing asymptomatic intracranial atherosclerotic disease.
Factors Associated with Visual Fatigue from Curved Monitor Use: A Prospective Study of Healthy Subjects
