Resistance and resilience to Alzheimer's disease in Down syndrome.

Due to the high prevalence of Alzheimer's disease (AD) in adults with Down syndrome (DS), trisomy 21 is now considered a genetic form of AD (DSAD). A better understanding of factors that can prevent or delay AD is vital to improve outcomes for adults with DS. In this narrative review, we apply AD and cognitive aging research frameworks to study resistance and resilience in DSAD. Given the variability in the timing of pathology and symptoms, we discuss the evidence supporting the role of genetic, biological, socio-behavioral, lifestyle, and environmental factors in resistance and resilience to DSAD. We also consider how co-occurring health conditions in DS may influence resistance and resilience, and how methods from AD research can be applied to DSAD. Ultimately, this framework aims to guide future research and translate findings into clinical interventions to improve outcomes in DSAD. Highlights Definitions of resistance and resilience in the genetic form of Alzheimer's disease (DSAD) are proposed for guiding the field. Variability in the timing of AD pathology and symptoms suggests the potential for resistance and resilience mechanisms in DSAD. Genetic, biological, socio-behavioral, lifestyle, and environmental factors have the potential to build resistance or resilience in DSAD. Future research will require longitudinal and experimental designs, life course approaches, and large cohort studies.