Genetic sample provision among national Alzheimer's coordinating center participants

Background: Genetic data help detect preclinical Alzheimer's disease and target individuals for clinical trials, making genetic research engagement critical for continued advancement in dementia prevention and treatment. Objective: To understand what individual and institutional factors may relate to provision of genetic samples within the Alzheimer's Disease Centers. Methods: Data from the National Alzheimer's Coordinating Center Uniform Data Set (2009-2016) were obtained along with genetic sample availability. Logistic regression was used to assess independent contributions of demographic and clinical characteristics to the probability of sample provision. Sites contributing data completed a brief survey exploring regulatory and scientific issues related to genetic research engagement. Results: Just over half (52.1%) of the 27,519 unique participants had genetic data available. Female sex, white race, non-Hispanic ethnicity, normal cognition, and greater than 5 years of follow-up were associated with greater probability of availability. Sites identified refusals as the most frequent barrier to sample provision, followed by staff availability. Conclusion: These results highlight the importance of strategies to promote minority engagement and encourage earlier genetic research participation.