Search

• The lifestyle for brain health (LIBRA) index has been associated with cognitive function. • Whether CD33 rs3865444 polymorphism can modulate the association between the LIBRA index and cognition in dementia-free older adults is unknown. • Our study suggested that a higher LIBRA index was associated with worse cognitive performance in rural Chinese older adults, especially among the CD33 CC carriers. • This study contributes to our further understanding of the complex relationships of modifiable lifestyles and the CD33 gene with cognitive function, which has potential implications for preventive interventions to maintain late-life brain and cognitive health. We sought to examine the associations of the Lifestyle for Brain Health (LIBRA) index with cognitive function among rural Chinese older adults and to explore the potential role of cluster of differentiation 33 gene (CD33) in the associations. This population-based cross-sectional study included 4914 dementia-free participants (age ≥60 years; 56.43 % women) in the 2018 baseline examination of MIND-China. The LIBRA index was generated from 11 factors. We used a neuropsychological test battery to assess episodic memory, verbal fluency, attention, executive function, and global cognition. The CD33 (rs3865444) polymorphism was detected using multiple-polymerase chain reaction amplification. Data were analyzed using the general linear regression models. A higher LIBRA index was associated with multivariable-adjusted β-coefficient (95 %CI) of -0.011(-0.020- -0.001) for global cognitive z-score, -0.020(-0.033- -0.006) for episodic memory, and -0.016(-0.029- -0.004) for verbal fluency. The CD33 (rs3865444) was associated with a lower global cognitive z-score in the additive (CA vs. CC: β-coefficient=0.042; 95 %CI=0.008–0.077), the dominant (CA+AA vs. CC: 0.040; 0.007–0.073), and the over-dominant (CA vs. CC+AA: 0.043; 0.009–0.077) models. Similar results were obtained for verbal fluency and attention. The CD33 gene showed statistical interactions with LIBRA index on cognitive function (P interaction <0.05) such that a higher LIBRA index was significantly associated with lower z-scores of global cognition and attention only among CD33 CC carriers (P < 0.05). This population-based study reveals for the first time that a higher LIBRA index is associated with worse cognitive performance in rural Chinese older adults and that CD33 gene could modify the association. [ABSTRACT FROM AUTHOR]

• A favorable CVH profile was associated with better physical function among rural chinese older adults. • The association was partially mediated via low chronic systemic inflammation. • This has implications for understanding the mechanisms linking CVH profile with physical function. We examined the association of modifiable cardiovascular health (CVH) metrics with physical function among rural older adults in China and the potential role of inflammatory mechanisms in the association. This study included 3733 stroke- and dementia-free participants (age ≥65 years; 56.9% women) in the baseline survey of a multimodal intervention study in rural China. From March-September 2018, data were collected via face-to-face interviews, clinical assessments, and laboratory tests. The Short Performance Physical Battery (SPPB) test was performed to assess physical function. We defined six modifiable CVH metrics according to the modified American Heart Association's recommendations. Serum interleukin (IL)-6 was measured in a subsample (n = 1156). Data were analyzed with multiple general linear and logistic regression models and structural equation modeling. Poor physical function (SPPB score ≤9) was defined in 1443 participants. Ideal CVH (vs. poor CVH) was associated with multivariable-adjusted odds ratio of 0.60 (95%CI 0.48–0.75) for poor physical function. Ideal CVH was significantly associated with higher scores on balance, chair stand, and walking speed tests (all p < 0.05). Moreover, ideal CVH profile was associated with lower serum IL-6 (multivariable-adjusted β=-0.04; 95% CI -0.06, -0.01). Mediation analysis revealed that serum IL-6 accounted for 14% of the association of CVH with total SPPB score and 10% of the association with walking speed score (p < 0.05). This study suggests that an ideal CVH profile is associated with better physical function among stroke- and dementia-free older adults, partly via inflammatory mechanisms. The preventive implications of these findings warrant further investigation in cohort studies. [ABSTRACT FROM AUTHOR]