Race and cognitive decline among community-dwelling elders with mild cognitive impairment: Findings from the Memory and Medical Care Study

Objective: Previous studies have reported conflicting findings on the relationship between race and cognitive decline in elders with dementia. Few studies have examined the role of race in cognitive decline in mild cognitive impairment (MCI). We investigate the relationship between race and cognitive decline in participants with MCI in a community-based, longitudinal study of cognitively impaired elders. Method: Based on a validated method utilizing a neuropsychiatric battery, 133 subjects [mean age: 78.7 years (SD=6.5); female: 112 (76.7%); black: 59 (44.4%)] out of 512 participants in the Memory and Medical Care Study were diagnosed with MCI. The main outcome measure was the Telephone Interview for Cognitive Status (TICS) score over three years. Other baseline subject characteristics (demographics, health-related variables, behavioral, and psychiatric symptoms) were included in the analysis. Results: Overall, the three-year decline in mean TICS score was significantly higher among African Americans than non-African Americans [3.31 (SD: 7.5) versus 0.96 (SD: 3.0), t-value=1.96, p-value=0.05]. General estimating equation analyses revealed that African American race was associated with a faster rate of cognitive decline in all models. Conclusion: The rate of cognitive decline in MCI appears to be faster in African Americans than non-African Americans in the community. Diagnosis of MCI among African American elders could lead to early interventions to prevent or delay cognitive decline in the future.