The link between C-reactive protein and Alzheimer's disease among Mexican Americans.

Background: The aim of this study is to evaluate the link between C-reactive protein (CRP) and Alzheimer's disease (AD) and mild cognitive impairment (MCI) among Mexican Americans.
Methods: Non-fasting serum CRP levels, Mini-Mental State Examination scores, and Clinical Dementia Rating scale (CDR) scores were analyzed from 1,066 participants (Mexican American n = 471; non-Hispanic n = 595) of the Texas Alzheimer's Research & Care Consortium.
Results: Among the total cohort, CRP levels among AD cases were significantly decreased as compared to normal controls (p < 0.001) and MCI cases (p = 0.002). CRP levels among MCI cases were decreased relative to controls (p = 0.03). Among Mexican American and non-Hispanic AD cases, CRP levels were significantly decreased among AD cases as compared to controls. CRP levels were only associated with disease severity (CDR scores) among non-Hispanics (p = 0.03) AD cases.
Conclusions: These results show that while CRP levels are decreased among Mexican American AD cases, CRP does not appear to be related to clinical variables as it is among non-Hispanic whites.