Racial/ethnic minorities have among the highest risks for Alzheimer disease and dementia, but remain underrepresented in clinical research studies.

To synthesize the current evidence on strategies to recruit and retain racial/ethnic minorities in Alzheimer disease and dementia clinical research.

We conducted a systematic review by searching CINAHL, EMBASE, MEDLINE, PsycINFO, and Scopus. We included studies that met four criteria: (1) included a racial/ethnic minority group (African American, Latino, Asian, American Indian or Alaska Native, and Native Hawaiian or Other Pacific Islander); (2) implemented a recruitment or retention strategy for Alzheimer disease or dementia clinical research; (3) conducted within the U.S.; and (4) published in a peer-reviewed journal.

Of the 19 included studies, 14 (73.7%) implemented recruitment strategies and 5 (26.3%) implemented both recruitment and retention strategies. Fifteen studies (78.9%) focused on African Americans, two (10.6%) on both African Americans and Latinos, and two (10.5%) on Asians. All the articles were rated weak in the study quality. Four major themes were identified for the recruitment strategies: community outreach (94.7%), advertisement (57.9%), collaboration with health care providers (42.1%), and referral (21.1%). Three major themes were identified for the retention strategies: follow-up communication (15.8%), maintain community relationship (15.8%), and convenience (10.5%).

Our findings highlight several promising recruitment and retention strategies that investigators should prioritize when allocating limited resources, however, additional well-designed studies are needed. By recruiting and retaining more racial/ethnic minorities in Alzheimer disease and dementia research, investigators may better understand the heterogeneity of disease progression among marginalized groups. PROSPERO registration #CRD42018081979.