Abstract TP137: Ethnic/racial Variations Of Intracerebral Hemorrhage Genetics (erich-gene) Study Protocol

Introduction: Epidemiologic studies of intracerebral hemorrhage (ICH) have consistently demonstrated variation in incidence, location, comorbidity burden, age-of-onset, and outcome by race and ethnicity, and genetic studies have identified differences in risk mediated by genetic risk factors such as Apolipoprotein E (APOE). We report the design and methods of the largest multi-ethnic genome-wide association study (GWAS) of ICH risk and outcome conducted to date.

Methods: The Ethnic/Racial Variations of ICH Genetics (ERICH-GENE) study is an international, multi-center, genetic case-control study of ICH. Cases are individuals with confirmed primary ICH with biosample availability and consent compatible with shareable genome-wide genotyping or previous genotyping. Central neuroimaging phenotype harmonization of case status, hemorrhage location, and imaging characteristics of cerebral small vessel disease including leukoaraiosis, atrophy, microbleeds, intraventricular hemorrhage severity and volume of ICH measurements will be performed. Controls are ICH-free individuals of compatible age and race/ethnicity from existing studies and biorepositories.

Results: As of August 2021, 2,002 ICH cases have been collected and genotyped, in addition to 2,558 already-genotyped ICH cases from the multi-ethnic ERICH study. 5,600 total new ICH cases will be genotyped under ERICH-GENE, with planned meta-analyses across existing ICH GWAS datasets and international biobanks totaling >20,000 cases. We are on schedule to meet our genotyping goal within the study period. Non-European ancestry cases are being prioritized for genotyping and ~66% of the previously genotyped ERICH cases are black or Hispanic. From available cases, a total of 10,621 neuroimaging studies have been uploaded for central adjudication to date with 6,278 having undergone harmonization.

Conclusions: ERICH-GENE is a large, multi-ethnic, international, centrally harmonized GWAS of ICH risk and outcome that will identify genetic risk factors across diverse populations for biological discovery and population-specific risk stratification.

Traumatic Brain Injury-Related Symptoms Reported by Parents: Clinical, Imaging, and Host Predictors in Children with Impairments in Consciousness Less than 24 Hours

This study examined the relationship between acute neuroimaging, host and injury factors, and parent-reported traumatic brain injury (TBI)-related symptoms in children with noncritical head injury at two weeks and three months after injury. Data were collected prospectively on 45 subjects aged three to 16 years old enrolled in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study. Subjects had rapid recovery of mental status (Glasgow Coma Score [GCS] = 15 within 24 h), and had no clinical need for neurosurgical intervention. Intra- or extra-axial magnetic resonance imaging (MRI) lesions were categorized using Common Data Elements (CDE) definitions. Host and acute injury factors including neurobehavioral history, race, extracranial injuries, loss of consciousness (LOC), and GCS were analyzed while controlling for pre-injury symptoms, age, sex, and socioeconomic status. Parent-reported cognitive and somatic symptoms were measured by the Health and Behavior Inventory (HBI). Forty-nine percent of children had MRI lesions, most of which were relatively small. LOC predicted increased cognitive and somatic symptoms at two weeks. At three months, pre-injury neurobehavioral history predicted increased cognitive and somatic symptoms. Neuroimaging findings did not predict parent-reported symptom severity, except at three months where extra-axial lesions were associated with less severe cognitive symptoms. While structural MRI lesions do not predict increased parent-reported symptoms in this population, age-specific child performance measures may be more sensitive outcome measures and require further study. Children with pre-injury neurobehavioral problems have more severe symptoms at three months and thus may benefit from longer follow-up and monitoring after traumatic brain injury.