[RE-SCHEDULED] Seminar by Dr. Tao Sun from School of Statistics, Renmin University of China

Alzheimer's disease (AD) is a progressive and polygenic disorder that affects millions of individuals each year. Given that there have been few effective treatments yet for AD, it is highly desirable to develop an accurate model to predict the full disease progression profile based on an individual's genetic characteristics for early prevention and clinical management. This work uses data composed of all four phases of the Alzheimer's Disease Neuroimaging Initiative (ADNI) study, including 1740 individuals with 8 million genetic variants. We tackle several challenges in this data, characterized by large-scale genetic data, interval-censored outcome due to intermittent assessments, and left truncation in one study phase (ADNIGO). Specifically, we first develop a semiparametric transformation model on interval-censored and left-truncated data and estimate parameters through a sieve approach. Then we propose a computationally efficient generalized score test to identify variants associated with AD progression. Next, we implement a novel neural network on interval-censored data (NN-IC) to construct a prediction model using top variants identified from the genome-wide test. Comprehensive simulation studies show that the NN-IC outperforms several existing methods in terms of prediction accuracy. Finally, we apply the NN-IC to the full ADNI data and successfully identify subgroups with differential progression risk profiles.

Dr. Tao Sun is an Associate Professor at the School of Statistics, Renmin University of China. He obtained his Ph.D. from the Department of Biostatistics at the University of Pittsburgh. His main research focuses on complex survival data models and risk management related to disability, dementia, and chronic diseases in the older population. He has led major and youth projects funded by the National Natural Science Foundation of China. His academic papers have been published in journals such as Biometrics, Biostatistics, and Statistical Methods in Medical Research. He serves as a council member of the Aging Economics Branch of the Chinese Association of Gerontology and Geriatrics.