Cross-sectional association between high-sensitivity C-reactive protein and cognitive function in community-dwelling older adults: the SONIC study

A decline in cognitive function is associated with inflammatory processes. However, the association between high-sensitivity C-reactive protein (hs-CRP) levels and cognitive decline in the Japanese population remains inconclusive. Thus, this study aimed to determine whether hs-CRP is associated with low cognitive function in 70- and 80-year-old community-dwelling Japanese individuals. The participants in this cross-sectional study were 872 Japanese residents aged 70 and 80 years who voluntarily participated in the Septuagenarians, Octogenarians, Nonagenarians Investigation with Centenarians (SONIC) study between 2010 and 2011. Blood sample collection, cognitive assessment, and other measurements were performed at the venue. Low cognitive function was defined as a score of 25 points or lower on the Japanese version of the Montreal Cognitive Assessment. The odds ratio (OR) and 95% confidence interval (95% CI) for each hs-CRP quartile were calculated using logistic regression analysis. A total of 288 (69.9%) parsons in the 70-year-old group and 372 (80.9%) in the 80-year-old group exhibited low cognitive function. The association between hs-CRP levels and low cognitive function was significant among 70- and 80-year-old Japanese community-dwelling adults. In particular, the fourth quartile of hs-CRP (0.727–7.420 mg/L) in the 70-year-old group and the second and fourth quartiles (0.214–0.404 and 0.911–9.890 mg/L) in the 80-year-old group were associated with low cognitive function. Furthermore, the third quartile (0.409–0.892 mg/L) in the 80-year-old group was closely associated with low cognitive function. High hs-CRP levels were associated with lower cognitive function in 70- and 80-year-old Japanese community-dwelling individuals, suggesting that high hs-CRP levels may influence cognitive function.