Association of polygenic risk scores with Alzheimer's disease and plasma biomarkers among Chinese older adults: A community-based study.

INTRODUCTION: We examined the associations of polygenic risk score (PRS) with Alzheimer's disease (AD) and plasma biomarkers in the Chinese population. METHODS: This population-based study used baseline data from MIND-China (2018; n = 4873) and follow-up data from dementia-free individuals (2014-2018; n = 2117). We measured AD-related plasma biomarkers in a subsample (n = 1256). Data were analyzed using logistic and Cox regression models. RESULTS: We developed PRS with (PRSAPOE) and without (PRSnon- APOE) apolipoprotein E (APOE) gene. In the longitudinal analysis, PRSAPOE was associated with a multivariable-adjusted hazards ratio of 1.91 (95% CI = 1.13-3.23) for AD. PRSAPOE in combination with demographics yielded discriminative (area under the curve [AUC]) and predictive(C-statistic) accuracy of 0.80 (95% confidence interval [CI] = 0.77-0.84) and 0.80 (0.77-0.82), respectively. PRSnon- APOE showed an association with AD risk similar to PRSAPOE. PRSAPOE, but not PRSnon- APOE, was associated with reduced plasma Aß42/Aß40 ratio and increased Neurofilament light chain (NfL) (p < 0.05). DISCUSSION: The PRS with and without APOE gene, in combination with demographics, shows good discriminative and predictive ability for AD. The AD-related pathologies underlie AD risk associated with PRSAPOE. HIGHLIGHTS: The PRSAPOE and PRSnon- APOE were associated with AD risk in the Chinese population. The PRSAPOE and PRSnon- APOE, in combination with demographics, showed good discriminative and predictive ability for AD. The AD-related pathologies underlie the AD risk associated with PRSAPOE but not PRSnon- APOE.

Cranial capacity measurement for modern Chinese adults based on 3D reconstruction.

OBJECTIVES: To determine the average modern adult cranial capacity in China, and assess the gender differences and trends in order to establish normal reference values and provide theoretical basis for individualized treatment in clinical practice. METHODS: We conducted a cross-sectional study between January 2019 to June 2020. Thin-slice (0.9 mm) CT scans of 309 males and 238 females from China were obtained, and classified into the 18-32, 33-47, 48-62, 63-77 and 78-92 years age groups. Three-dimensional reconstruction was performed using mimics software to obtain the cranial capacity for statistical analysis. RESULTS: The average cranial capacity of men was 1497.12±120.70 cm3 and that of women was 1326.24±95.72 cm3. The average cranial capacity of men was larger than that of women in all age groups. In addition, cranial capacity across the different age groups showed significant differences among both men and women. CONCLUSION: The average cranial capacity of modern Chinese male is larger that of females, and both sexes show a tendency to an increase in the intracranial volume over the past few decades. Our findings provide important data for establishing normal reference values for cranial capacity of modern Chinese adults and theoretical basis for individualized treatment of certain cranial diseases with increased intracranial pressure.