The risk of an observed impairment was significantly reduced by the use of antihypertensives (HR, 0.34) and a report of high cholesterol (HR, 0.75).
Dr. Abner acknowledged certain limitations of the study, including the fact that most clinical impairments are not yet confirmed by medical review. In addition, "relevant early to midlife socioeconomic status exposures were not measured, which may mitigate the effect observed for black race," she said. "Also, many of our black participants were recruited from Veterans Affairs sites, so their exposures may be qualitatively different in terms of their risk of head trauma and PTSD [posttraumatic stress disorder]. Overall, the sample was highly educated and healthy."
Screening of the full PREADVISE cohort is expected to be completed in early 2014.
The study is funded by the National Institute on Aging. Dr. Abner said she had no relevant financial conflicts to disclose.