Study Protocol: Asymptomatic Intracranial Atherosclerotic Disease in Pakistanis

Abstract

Conflict of Interest—None declared.
Background—Intracranial atherosclerotic disease (ICAD) is the most frequent subtype of ischemic stroke
globally. It is important to describe the determinants of early ICAD as a strategy to prevent strokes from
clinically evident and progressive ICAD. Our objective is to report the determinants of asymptomatic
ICAD by linking the presence or absence of ICAD on magnetic resonance angiogram (MRA) with detailed
risk assessment in asymptomatic adults.
Methods—This is an observational cross-sectional analytical study. We plan to recruit 200 adult participants from the radiology departments of two tertiary care centers of Karachi, Pakistan. The participants will
first be screened for the absence of stroke symptoms via the Questionnaire for Verifying Stroke Free Status
(QVSFS). QVSFS negative will be participants will be eligible. After written informed consent, participants will undergo detailed medical, sociodemographic, lifestyle, and anthropometric evaluation by a
detailed interview. They will, in addition, undergo MRA to study the presence, degree, and distribution of
asymptomatic ICAD. All MRA scans will be reviewed centrally by vascular neurologists blinded to clinical
information. These images would be reviewed on DICOM Viewer 3.0 used for calculating the degree of
stenosis using Warfarin–Aspirin Symptomatic Intracranial Disease (WASID) study defined criteria
employing electronic calipers. A sample size of 200 will achieve 80% power for detecting a minimum difference of 20% in the prevalence of exposure factors (medical and lifestyle) between asymptomatic ICAD positive and ICAD negative persons. This study will generate regional data on risks for ICAD development
and prevention in a high-risk susceptible population.
Study ID: NCT02072876