Nearly 60 lifestyle and psychological traits were evaluated with cognitive functioning in established adulthood in CATSLife using robust and cotwin-control methods. Results revealed that an appreciation for cognitive complexity and a sense of purpose in life may be protective to cognitive functioning, controlling for genetic and environmental confounds, in addition to the well-known risk from smoking.
Using the CATSLife sample, we developed a frailty index with sibling similarity patterns suggesting that moderate genetic influences contribute to frailty differences in early adulthood. Moreover, frailty is associated with worse performance on the Digit Symbol Substitution Subtest, a processing speed task evidencing increasingly stronger associations at higher ages. Thus, even in adults approaching midlife, an understudied period within lifespan development, indicators of vulnerability to stress as indexed by frailty are associated with processing speed and warrant additional longitudinal investigation.
Using data from the IGEMS consortium, we observed that for Semantic Fluency and Episodic Memory tasks, genetic influences contribute to cognitive function at shorter sleep durations (4 hours) to a greater degree than at longer sleep durations (10 hours), consistent with prior work in the field suggesting that short sleep may be associated with an upregulation of neuroinflammatory processes and ineffective beta-amyloid clearance.
The first report to include polygenic scores for Alzheimer's disease (AD) simultaneously in a biometrical twin model of AD risk in Swedish twins. APOE accounts for much of the measured polygenic contribution with substantial background genetic influences still to be understood.
