No abstract

Like virtually all age-related chronic diseases, late-onset Alzheimer’s disease (AD) develops over an extended preclinical period and is associated with modifiable lifestyle and environmental factors. We hypothesize that multimodal interventions that address many risk factors simultaneously and are individually tailored to patients may help reduce AD risk. We describe a novel clinical methodology used to evaluate and treat patients at two Alzheimer’s Prevention Clinics. The framework applies evidence-based principles of clinical precision medicine to tailor individualized recommendations, follow patients longitudinally to continually refine the interventions, and evaluate N-of-1 effectiveness (trial registered at ClinicalTrials.gov NCT03687710). Prior preliminary results suggest that the clinical practice of AD risk reduction is feasible, with measurable improvements in cognition and biomarkers of AD risk. We propose using these early findings as a foundation to evaluate the comparative effectiveness of personalized risk management within an international network of clinician researchers in a cohort study possibly leading to a randomized controlled trial.

Hyperinsulinemia is a risk factor for late-onset Alzheimer's disease (AD).In vitro experiments describe potential connections between insulin, insulin signaling, and amyloid-␤ (A␤), but in vivo experiments are needed to validate these relationships under physiological conditions. First, we performed hyperinsulinemic-euglycemic clamps with concurrent hippocampal microdialysis in young, awake, behaving APP swe /PS1 dE9 transgenic mice. Both a postprandial and supraphysiological insulin clamp significantly increased interstitial fluid (ISF) and plasma A␤ compared with controls. We could detect no increase in brain, ISF, or CSF insulin or brain insulin signaling in response to peripheral hyperinsulinemia, despite detecting increased signaling in the muscle. Next, we delivered insulin directly into the hippocampus of young APP/PS1 mice via reverse microdialysis. Brain tissue insulin and insulin signaling was dose-dependently increased, but ISF A␤ was unchanged by central insulin administration. Finally, to determine whether peripheral and central high insulin has differential effects in the presence of significant amyloid pathology, we repeated these experiments in older APP/PS1 mice with significant amyloid plaque burden. Postprandial insulin clamps increased ISF and plasma A␤, whereas direct delivery of insulin to the hippocampus significantly increased tissue insulin and insulin signaling, with no effect on A␤ in old mice. These results suggest that the brain is still responsive to insulin in the presence of amyloid pathology but increased insulin signaling does not acutely modulate A␤ in vivo before or after the onset of amyloid pathology. Peripheral hyperinsulinemia modestly increases ISF and plasma A␤ in young and old mice, independent of neuronal insulin signaling.

Introduction The NIH Toolbox Cognition Battery (NIHTB-CB) is a computer-based protocol not yet validated for clinical assessment. Methods We administered the NIHTB-CB and traditional neuropsychological tests to 247 Memory Disorders and Alzheimer's Prevention Clinic patients with subjective cognitive decline, mild cognitive impairment, mild dementia due to Alzheimer's disease, and normal cognition. Principal component analysis, partial correlations, and univariate general linear model tests were performed to assess construct validity. Discriminant function analyses compared classification accuracy. Results Principal component analysis identified three conceptually coherent factors: memory (MEM NIH ), executive function (EF NIH ), and crystallized intelligence (CI NIH ). These factors were strongly associated with corresponding traditional tests and differed across diagnostic groups as expected. Both NIHTB and traditional batteries yielded strong overall discriminative ability (>80%). Discussion The NIHTB-CB is a valid method to assess neurocognitive domains pertinent to aging and dementia and has utility for applications in a memory clinic setting.

Summary INTRODUCTION: Multi-domain intervention for Alzheimer’s disease (AD) risk reduction is an emerging therapeutic paradigm. METHODS: Patients were prescribed individually-tailored interventions (education/pharmacologic/non-pharmacologic) and rated on compliance. Normal cognition/subjective cognitive decline/preclinical-AD were classified as Prevention. Mild cognitive impairment due to AD/mild-AD were classified as Early Treatment. Change from baseline to 18-months on the modified-Alzheimer’s Prevention Cognitive Composite (primary outcome) was compared against matched historical control cohorts. Cognitive aging composite (CogAging), AD/cardiovascular risk-scales, and serum biomarkers were secondary outcomes. RESULTS: 174 were assigned interventions (age 25–86). Higher-compliance Prevention improved more than both historical cohorts (P=.0012,P<.0001). Lower-compliance Prevention also improved more than both historical cohorts (P=.0088,P<.0055). Higher-compliance Early Treatment improved more than lower-compliance (P=.0007). Higher-compliance Early Treatment improved more than historical cohorts (P<.0001,P=.0428). Lower-compliance Early Treatment did not differ (P=.9820,P=.1115). Similar effects occurred for CogAging. AD/cardiovascular risk-scales and serum biomarkers improved. DISCUSSION: Individualized multi-domain interventions may improve cognition and reduce AD/cardiovascular risk scores in patients at-risk for AD-dementia.