Serum inflammatory proteins and cognitive decline in older persons.

To assess whether serum levels of the inflammatory proteins alpha(1)-antichymotrypsin (ACT), C-reactive protein (CRP), interleukin-6 (IL-6), and albumin are associated with cognitive decline in older persons. The study sample consisted of 1,284 participants in the Longitudinal Aging Study Amsterdam, aged 62 to 85 years. Cognition was assessed on general cognition (Mini-Mental State Examination [MMSE]), memory (Auditory Verbal Learning Test), fluid intelligence (Raven's Colored Progressive Matrices), and information-processing speed (Coding Task) at baseline and at 3-year follow-up. The highest tertile of ACT was associated with an increased risk of decline on the MMSE (age-, sex-, education-adjusted odds ratio [OR] 1.60; 95% CI: 1.05 to 2.43) but not on any other cognitive test score. CRP, IL-6, and albumin were not associated with cognitive decline on any cognitive test in our study. This population-based study showed that the serum inflammatory protein alpha1-antichymotrypsin is associated with cognitive decline in older persons, whereas C-reactive protein, interleukin-6, and albumin are not.