Williamson, Jeff D.

Abstract Since 2016, the Alzheimer's Association and the Fondation Alzheimer have hosted Global Alzheimer's Leadership Series (GoALS) global think tanks, with world‐leading experts for innovative discussions to advance Alzheimer's disease (AD) research and care. The second GoALS think tank, held in June 2024 in Paris, focused on the relationship between biological changes and clinical manifestations of AD in the context of the evolving therapeutic landscape. Discussions spanned real‐world experiences of providers, patients, and their families, theoretical considerations, and health system challenges. The lived experience perspective was central to these discussions. The importance of shared decision‐making, clear and transparent communication, and the need for real‐world data to holistically support patients during their experiences were highlighted. This manuscript shares key insights from both the think tank meeting in Paris and a featured research session at the 2024 Alzheimer's Association International Conference that expanded the discussion themes for broader dissemination with the community.

ImportanceIncreased white matter hyperintensity (WMH) volume is a common magnetic resonance imaging (MRI) finding in both autosomal dominant Alzheimer disease (ADAD) and late-onset Alzheimer disease (LOAD), but it remains unclear whether increased WMH along the AD continuum is reflective of AD-intrinsic processes or secondary to elevated systemic vascular risk factors.ObjectiveTo estimate the associations of neurodegeneration and parenchymal and vessel amyloidosis with WMH accumulation and investigate whether systemic vascular risk is associated with WMH beyond these AD-intrinsic processes.Design, Setting, and ParticipantsThis cohort study used data from 3 longitudinal cohort studies conducted in tertiary and community-based medical centers—the Dominantly Inherited Alzheimer Network (DIAN; February 2010 to March 2020), the Alzheimer’s Disease Neuroimaging Initiative (ADNI; July 2007 to September 2021), and the Harvard Aging Brain Study (HABS; September 2010 to December 2019).Main Outcome and MeasuresThe main outcomes were the independent associations of neurodegeneration (decreases in gray matter volume), parenchymal amyloidosis (assessed by amyloid positron emission tomography), and vessel amyloidosis (evidenced by cerebral microbleeds [CMBs]) with cross-sectional and longitudinal WMH.ResultsData from 3960 MRI sessions among 1141 participants were included: 252 pathogenic variant carriers from DIAN (mean [SD] age, 38.4 [11.2] years; 137 [54%] female), 571 older adults from ADNI (mean [SD] age, 72.8 [7.3] years; 274 [48%] female), and 318 older adults from HABS (mean [SD] age, 72.4 [7.6] years; 194 [61%] female). Longitudinal increases in WMH volume were greater in individuals with CMBs compared with those without (DIAN: t = 3.2 [P = .001]; ADNI: t = 2.7 [P = .008]), associated with longitudinal decreases in gray matter volume (DIAN: t = −3.1 [P = .002]; ADNI: t = −5.6 [P < .001]; HABS: t = −2.2 [P = .03]), greater in older individuals (DIAN: t = 6.8 [P < .001]; ADNI: t = 9.1 [P < .001]; HABS: t = 5.4 [P < .001]), and not associated with systemic vascular risk (DIAN: t = 0.7 [P = .40]; ADNI: t = 0.6 [P = .50]; HABS: t = 1.8 [P = .06]) in individuals with ADAD and LOAD after accounting for age, gray matter volume, CMB presence, and amyloid burden. In older adults without CMBs at baseline, greater WMH volume was associated with CMB development during longitudinal follow-up (Cox proportional hazards regression model hazard ratio, 2.63; 95% CI, 1.72-4.03; P < .001).Conclusions and RelevanceThe findings suggest that increased WMH volume in AD is associated with neurodegeneration and parenchymal and vessel amyloidosis but not with elevated systemic vascular risk. Additionally, increased WMH volume may represent an early sign of vessel amyloidosis preceding the emergence of CMBs.

Abstract Whether initiation of statins could increase survival free of dementia and disability in adults aged ≥75 years is unknown. PREVENTABLE, a double‐blind, placebo‐controlled randomized pragmatic clinical trial, will compare high‐intensity statin therapy (atorvastatin 40 mg) with placebo in 20,000 community‐dwelling adults aged ≥75 years without cardiovascular disease, disability, or dementia at baseline. Exclusion criteria include statin use in the prior year or for >5 years and inability to take a statin. Potential participants are identified using computable phenotypes derived from the electronic health record and local referrals from the community. Participants will undergo baseline cognitive testing, with physical testing and a blinded lipid panel if feasible. Cognitive testing and disability screening will be conducted annually. Multiple data sources will be queried for cardiovascular events, dementia, and disability; survival is site‐reported and supplemented by a National Death Index search. The primary outcome is survival free of new dementia or persisting disability. Co‐secondary outcomes are a composite of cardiovascular death, hospitalization for unstable angina or myocardial infarction, heart failure, stroke, or coronary revascularization; and a composite of mild cognitive impairment or dementia. Ancillary studies will offer mechanistic insights into the effects of statins on key outcomes. Biorepository samples are obtained and stored for future study. These results will inform the benefit of statins for increasing survival free of dementia and disability among older adults. This is a pioneering pragmatic study testing important questions with low participant burden to align with the needs of the growing population of older adults.

ImportanceFalls and fractures are frequent and deleterious to the health of older people. Aspirin has been reported to reduce bone fragility and slow bone loss.ObjectiveTo determine if daily low-dose aspirin (100 mg) reduces the risk of fractures or serious falls (fall-related hospital presentations) in healthy older men and women.Design, Setting, and ParticipantsThis substudy of a double-blind, randomized, placebo-controlled trial studied older adult men and women in 16 major sites across southeastern Australia. The ASPREE-FRACTURE substudy was conducted as part of the Australian component of the ASPREE trial. Between 2010 and 2014 healthy (free of cardiovascular disease, dementia or physical disability), community-dwelling volunteers aged 70 years or older were recruited to participate in the ASPREE trial. Potentially eligible participants were identified by medical practitioners and trial personnel and were then sent a letter of invitation to participate. Interested participants were screened for suitability. Eligible participants with medical practitioner authorization and adherent to a 4-week run-in medication trial were randomized. Data were analyzed from October 17, 2019, to August 31, 2022.InterventionsParticipants in the intervention group received a daily dose of oral 100 mg enteric-coated (low-dose) aspirin. The control group received a daily identical enteric-coated placebo tablet.Main Outcomes and MeasuresThe primary outcome of ASPREE-FRACTURE was the occurrence of any fracture. The secondary outcome was serious fall resulting in hospital presentation.ResultsIn total, 16 703 people with a median (IQR) age of 74 (72-78) years were recruited, and 9179 (55.0%) were women. There were 8322 intervention participants and 8381 control participants included in the primary and secondary outcome analysis of 2865 fractures and 1688 serious falls over the median follow-up of 4.6 years. While there was no difference in the risk of first fracture between the intervention and control participants (hazard ratio, 0.97; 95% CI, 0.87-1.06; P = .50), aspirin was associated with a higher risk of serious falls (total falls 884 vs 804; incidence rate ratio, 1.17; 95% CI, 1.03-1.33; P = .01). Results remained unchanged in analyses that adjusted for covariates known to influence fracture and fall risk.Conclusions and RelevanceIn this substudy of a randomized clinical trial, the failure of low-dose aspirin to reduce the risk of fractures while increasing the risk of serious falls adds to evidence that this agent provides little favorable benefit in a healthy, White older adult population.Trial RegistrationThis substudy is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12615000347561).

AbstractBackgroundHypertension is a major risk factor for cardiovascular and cerebrovascular disease including stroke, small vessel disease, and dementia. The Systolic blood PRessure INTervention (SPRINT) randomized trial prospectively evaluated the effects of intensive systolic blood pressure (SBP) control (target SBP<120mmHg) versus standard control (SBP<140mmHg) on cardiovascular outcomes in individuals without baseline diabetes or stroke, and included cerebral blood flow (CBF) measurements. Previous studies with much smaller sample sizes and shorter duration suggested stable CBF in response to intensive treatment (SBP<125mmHg) [1], but long term effects are unknown. We evaluated the long‐term effects of intensive blood pressure treatment on CBF.MethodWhole brain CBF was measured at 3T using pseudocontinuous arterial spin labeled (ASL) perfusion MRI at baseline and after 3.9±0.3 years. Total white matter lesion (WML) load was measured from Fluid Attenuated Inversion Recovery T2 MRI. Data from 324 subjects with adequate ASL scan quality acquired from 6 sites were included.ResultDemographics and scanner specific CBF values are provided in Table 1. The intensive treatment group was older (p=0.01), but was otherwise similar to the standard group at baseline. There was a significant effect on the longitudinal CBF change (p=0.006) of the intensive treatment (5.7% increase) compared to the standard treatment (4.0% decrease, Fig 1). Secondary analysis showed a significant increase in age‐adjusted fractional CBF for the intensive treatment group (p<0.001) with no change (p=0.24) in the standard treatment group. Change in CBF was not associated with change in WML.ConclusionSustained intensive antihypertensive treatment does not reduce whole brain CBF, in fact it showed an increase in whole brain CBF relative to standard therapy. While improved CBF might contribute to the reduced WML progression observed in the intensive‐therapy group versus standard therapy in SPRINT[2], we did not observe a direct correlation between CBF changes and WML changes. References: (1) Croall et al. JAMA‐Neurol,2018; (2) Nasrallah et al., JAMA‐Neurol, 2019.

Abstract Vascular contributions to cognitive impairment and dementia (VCID) are characterized by the aging neurovascular unit being confronted with and failing to cope with biological insults due to systemic and cerebral vascular disease, proteinopathy including Alzheimer's biology, metabolic disease, or immune response, resulting in cognitive decline. This report summarizes the discussion and recommendations from a working group convened by the National Heart, Lung, and Blood Institute and the National Institute of Neurological Disorders and Stroke to evaluate the state of the field in VCID research, identify research priorities, and foster collaborations. As discussed in this report, advances in understanding the biological mechanisms of VCID across the wide spectrum of pathologies, chronic systemic comorbidities, and other risk factors may lead to potential prevention and new treatment strategies to decrease the burden of dementia. Better understanding of the social determinants of health that affect risks for both vascular disease and VCID could provide insight into strategies to reduce racial and ethnic disparities in VCID.

Significance Statement Intensive treatment of hypertension is beneficial for cardiovascular disease and cognitive function, but at the short-term expense of reduced kidney function. In a randomized trial of intensive versus standard systolic BP lowering, the authors found an association between a large decline in eGFR and increased incidence of probable dementia and mild cognitive impairment, but no link between urinary albumin-to-creatinine ratio and occurrence of dementia or mild cognitive impairment. Decline in eGFR occurred more frequently in the intensive treatment group, but did not modify the beneficial effect of intensive treatment on cognitive function. Among hypertensive adults, declining eGFR may be a marker for those at higher risk for dementia or mild cognitive impairment, independent of the intensity of hypertension treatment. Background Intensively treating hypertension may benefit cardiovascular disease and cognitive function, but at the short-term expense of reduced kidney function. Methods We investigated markers of kidney function and the effect of intensive hypertension treatment on incidence of dementia and mild cognitive impairment (MCI) in 9361 participants in the randomized Systolic Blood Pressure Intervention Trial, which compared intensive versus standard systolic BP lowering (targeting <120 mm Hg versus <140 mm Hg, respectively). We categorized participants according to baseline and longitudinal changes in eGFR and urinary albumin-to-creatinine ratio. Primary outcomes were occurrence of adjudicated probable dementia and MCI. Results Among 8563 participants who completed at least one cognitive assessment during follow-up (median 5.1 years), probable dementia occurred in 325 (3.8%) and MCI in 640 (7.6%) participants. In multivariable adjusted analyses, there was no significant association between baseline eGFR <60 ml/min per 1.73 m 2 and risk for dementia or MCI. In time-varying analyses, eGFR decline ≥30% was associated with a higher risk for probable dementia. Incident eGFR <60 ml/min per 1.73 m 2 was associated with a higher risk for MCI and a composite of dementia or MCI. Although these kidney events occurred more frequently in the intensive treatment group, there was no evidence that they modified or attenuated the effect of intensive treatment on dementia and MCI incidence. Baseline and incident urinary ACR ≥30 mg/g were not associated with probable dementia or MCI, nor did the urinary ACR modify the effect of intensive treatment on cognitive outcomes. Conclusions Among hypertensive adults, declining kidney function measured by eGFR is associated with increased risk for probable dementia and MCI, independent of the intensity of hypertension treatment.