It has been a significant year of change and learning for the Black and African American Connections to Parkinson’s Disease (BLAAC PD) study, including the recruitment of the 1,000th participant since its inception. BLAAC PD is becoming the most extensive study of Black and African American people with Parkinson’s disease and aims to understand the genetics of Parkinson’s in this population while providing the research community with valuable insights about the recruitment of underrepresented participants.
2025 Protocol Amendment
As a flexible and growing study, BLAAC PD has been an excellent platform for growth and expansion. In an effort to continue closing the health disparities and knowledge gaps between those of European ancestry and of African and African-admixed ancestries, BLAAC PD spent much of 2024 discussing the best way to assess cognition in BLAAC PD–a direct response to the novel GBA1 African variant that researchers discovered in 2023. It aims to make data from the BLAAC PD cohort more readily available for discovery follow-up.
After discussions and guidance from cognition experts, BLAAC PD implemented the Montreal Cognitive Assessment (MoCA) in 2025, along with self-reported REM sleep behavior disorder (RBD). The novel GBA1 variant discovery in 2023 prompted the addition of both assessments. The literature shows links between GBA1 gene carriers and cognition, so collecting the MoCA will allow BLAAC PD to contribute to research on the novel GBA1 variant and cognition. In 2024, GP2 contributors and members of the Nigerian Parkinson’s Diseases Research Network found that individuals in Nigeria with the novel GBA1 variant were more likely to experience RBD. Therefore, the addition of this question in BLAAC PD may allow for further research in this area.
With growing interest in environmental exposures across GP2 and under the leadership of BLAAC PD’s Principal Investigator, Lana Chahine, who is involved in the GP2 Environmental Interest Group, the team also implemented an early edition of the Modified Mini Environmental Risk Questionnaire (MERQ) in BLAAC PD’s 2025 protocol amendment.
BLAAC PD Annual Meeting
On August 13th, BLAAC PD held its 2nd Annual Meeting, convening investigators and coordinators from the study’s eleven active sites across the United States. During the meeting, a significant point of discussion was the need to identify where Black and African Americans living with PD receive health services. As BLAAC PD approaches its control recruitment goal and more sites begin exhausting in-clinic recruitment of cases, the study is striving to generate new strategies for successful case recruitment through both the BLAAC PD study and the BLAAC PD Recruitment Demonstration Project.
Much of the meeting included a discussion around results and genetic data from BLAAC PD generated thus far. Genetic data on 533 BLAAC PD participants is currently available, and 430 have whole genome sequencing (WGS) data available, as of GP2 release 10. Data shows variation in ancestry distribution, emphasizing the critical role BLAAC PD plays in contributing to data from people of African admixed ancestry.
BLAAC PD Recruitment Learnings and Achievements
August 2025 marked a significant milestone in BLAAC PD. Since starting in 2021, BLAAC PD has grown significantly, and after 4 years, BLAAC PD enrolled its 1,000th participant in late August. At the outset, BLAAC PD study leaders were uncertain about what recruitment would be like, what would be feasible, and what recruitment goals would be needed to achieve enough statistical power for scientific analyses. With over 1,000 participants in BLAAC PD, the initiative has experienced many successes and challenges in recruitment, which researchers have documented in the Roadmap for Community-Engaged BLAAC PD Recruitment. This year, study leaders, site investigators, and BLAAC PD’s community engagement partner, NORC at the University of Chicago, drafted a review paper discussing practical strategies that have enhanced recruitment across BLAAC PD sites. The paper was recently submitted to the Journal of Parkinson’s Disease for publication.
Last year, ASAP awarded a grant for a recruitment-focused project within BLAAC PD called the BLAAC PD Recruitment Demonstration Project. Through this funding, three sites—Washington University in St. Louis, Louisiana State University Health Sciences Center, Shreveport, and UTHealth Houston—received additional support and resources for testing recruitment strategies. All three sites began focus groups and Community Advisory Board meetings this year, engaging Black and African American community members in considering strategies that may be most successful for recruitment. The implementation of the strategies, including partnerships with local neurologists and federally qualified health centers, has begun. The team will collect and analyze qualitative and quantitative data and outcomes, hoping to identify successful strategies that other BLAAC PD sites can replicate and that other Parkinson’s disease research studies seeking to diversify participation can use.
As of September 30th, BLAAC PD has enrolled 1,060 participants, which includes 652 controls and 408 cases. Since the team implemented smell testing in 2024, 570 participants (53.8% of the total) have completed the Revised English Smell Identification Test. Additionally, the team has collected the MoCA from 160 participants.
Look Ahead to 2026
As 2025 comes to a close and the initiative welcomes a new year, BLAAC PD is looking more closely at recruitment strategies to engage Black and African Americans living with PD. Control recruitment has come easily for the study, thanks to community engagement efforts like tabling at fairs, educational events, and via word of mouth. Case recruitment has been far slower, primarily due to systemic barriers like limited access to care and delayed diagnosis. While BLAAC PD is unable to address these larger systemic barriers, the study team will be testing a new recruitment strategy aimed at generating case referrals from outside clinics and institutions to BLAAC PD sites. The new strategy will launch in January 2026 with 3 BLAAC PD sites and will expand to other sites later in the year. With this new strategy, the BLAAC PD study will also integrate more quantitative data collection measures on recruitment and enrollment, with the hope of informing future publications on strategies for engaging underrepresented populations in research. The first review paper on insights from BLAAC PD’s first four years will be published in early 2026.
Bittersweet Farewell
Since 2021, Sara Bandres-Ciga has led BLAAC PD. Under her leadership, the BLAAC PD study launched and continued to grow. Specifically, the study onboarded several new sites over the past three years, added smell testing in 2023, and utilized BLAAC PD data for analyses and discoveries (read the February 2024 update here). We are all immensely grateful for the guidance and leadership Sara provided over the past several years, as well as her support in seamlessly integrating BLAAC PD into the broader work of GP2.
