Emerging drugs for dementia with Lewy Bodies: a review of Phase II & III trials

The Interplay of Food Insecurity, Diet Quality, and Dementia Status in their Association with All-Cause Mortality Among Older US Adults in the Health and Retirement Study 2012-2020

BACKGROUND

All-cause mortality risk and dementia occurrence have been previously hypothesized to be linked with food insecurity and poor dietary quality.

OBJECTIVE

The aims of the study were to test mediation and interactions between food insecurity, diet quality, and dementia status in relation to all-cause mortality.

DESIGN

The interplay of food insecurity, diet quality, and dementia in their associations with all-cause mortality was studied, in terms of interactions and mediating effects, using secondary longitudinal data from a sample of older US adults from the Health and Retirement Study (HRS, 2012-2020). Reduced (age, sex, race/ethnicity-adjusted, M1) and fully adjusted (sociodemographic, lifestyle, and health-related factor-adjusted, M2) models were tested, and stratification by sex and race/ethnicity was carried out.

PARTICIPANTS/SETTING

US older adults (n = 2894; 2012-2014, mean baseline age of 76.4 y) were selected from this national longitudinal sample.

MAIN OUTCOME MEASURES

The outcome of interest was all-cause mortality risk for follow-up until the end of 2020.

STATISTICAL ANALYSES PERFORMED

Cox proportional hazards, four-way decomposition, and generalized structural equations models (GSEM) were used.

RESULTS

Overall, 902 deaths occurred (51 per 1000 person-years). Food insecurity (yes vs no) was not associated with mortality risk in M1, although inversely related to this outcome in M2 (Cox models and GSEM). Food insecurity was directly related to Ln(dementia odds) in M1 only (β ± standard error [SE]: 0.23 ± 0.05, P < .001, GSEM). Diet quality as measured by HEI-2015 (z-scored), although inversely related to food insecurity in reduced GSEM (β ± SE: -0.18 ± 0.06, P = .005), was also inversely related to both Ln(dementia odds), z-scored (β ± SE: -0.14 ± 0.03l P < .001) and mortality risk (LnHR ± SE: -0.14 ± 0.03; P < .001, M1). Ln(dementia odds) was strongly associated with mortality risk (HR = 1.39; 95% CI, 1.31-1.48; P < .001, M2). In both four-way decomposition models and GSEM, the total effect of diet quality on mortality risk was partially mediated through Ln(dementia odds) (M1 and M2), explaining 15%-21% of this total effect.

CONCLUSION

Diet quality-mortality risk association was partially mediated through dementia, with inconsistent findings observed for food insecurity.

The mechanisms, hallmarks, and therapies for brain aging and age-related dementia

Age-related cognitive decline and dementia are significant manifestations of brain aging. As the elderly population grows rapidly, the health and socio-economic impacts of cognitive dysfunction have become increasingly significant. Although clinical treatment of dementia has faced considerable challenges over the past few decades, with limited breakthroughs in slowing its progression, there has been substantial progress in understanding the molecular mechanisms and hallmarks of age-related dementia (ARD). This progress brings new hope for the intervention and treatment of this disease. In this review, we categorize the latest findings in ARD biomarkers into four stages based on disease progression: Healthy brain, pre-clinical, mild cognitive impairment, and dementia. We then systematically summarize the most promising therapeutic approaches to prevent or slow ARD at four levels: Genome and epigenome, organelle, cell, and organ and organism. We emphasize the importance of early prevention and detection, along with the implementation of combined treatments as multimodal intervention strategies, to address brain aging and ARD in the future.

Lewy Body Dementia

OBJECTIVE

Lewy body dementia (LBD) is an umbrella term describing two closely related conditions: Parkinson disease dementia (PDD) and dementia with Lewy bodies (DLB). LBD is the second most common cause of neurodegenerative dementia but is often underrecognized in clinical practice. This review covers the key epidemiologic, clinical, cognitive, behavioral, and biomarker features of LBD and discusses current treatment options.

LATEST DEVELOPMENTS

Indicative biomarkers of LBD improve the ability to make a diagnosis and include single-photon emission computed tomography (SPECT) of the dopamine system (brain) and the noradrenergic system (cardiac), and polysomnography. α-Synuclein-specific biomarkers in spinal fluid, skin, plasma, and brain imaging are in active development with some available for clinical use. Prodromal stages of PDD and DLB have been contextualized, and diagnostic criteria have been published. An emerging theme is whether an integrated staging system focusing on protein aggregation, rather than clinical symptoms, may advance research efforts.

ESSENTIAL POINTS

LBD is a common cause of cognitive impairment in older adults but is often subject to significant delays in diagnosis and treatment, increasing the burden on patients and family care partners. Understanding key features of disease and the use of biomarkers will improve recognition. Earlier detection may also facilitate the development of new therapeutics and enrollment in clinical trials.

Practical use of DAT SPECT imaging in diagnosing dementia with Lewy bodies: a US perspective of current guidelines and future directions

Background

Diagnosing Dementia with Lewy Bodies (DLB) remains a challenge in clinical practice. The use of 123I-ioflupane (DaTscan™) SPECT imaging, which detects reduced dopamine transporter (DAT) uptake-a key biomarker in DLB diagnosis-could improve diagnostic accuracy. However, DAT imaging is underutilized despite its potential, contributing to delays and suboptimal patient management.

Methods

This review evaluates DLB diagnostic practices and challenges faced within the U.S. by synthesizing information from current literature, consensus guidelines, expert opinions, and recent updates on DaTscan FDA filings. It contrasts DAT SPECT with alternative biomarkers, provides recommendations for when DAT SPECT imaging may be indicated and discusses the potential of emerging biomarkers in enhancing diagnostic approaches.

Results

The radiopharmaceutical 123I-ioflupane for SPECT imaging was initially approved in Europe (2000) and later in the US (2011) for Parkinsonism/Essential Tremor. Its application was extended in 2022 to include the diagnosis of DLB. DaTscan's diagnostic efficacy for DLB, with its sensitivity, specificity, and predictive values, confirms its clinical utility. However, US implementation faces challenges such as insurance barriers, costs, access issues, and regional availability disparities.

Conclusion

123I-ioflupane SPECT Imaging is indicated for DLB diagnosis and differential diagnosis of Alzheimer's Disease, particularly in uncertain cases. Addressing diagnostic obstacles and enhancing physician-patient education could improve and expedite DLB diagnosis. Collaborative efforts among neurologists, geriatric psychiatrists, psychologists, and memory clinic staff are key to increasing diagnostic accuracy and care in DLB management.

A Coalition to Advance Treatments for Parkinson's Disease, Dementia with Lewy Bodies, and Related Disorders

Parkinson's disease (PD) and dementia with Lewy bodies (DLB) share underlying neuropathology. Despite overlapping biology, therapeutic development has been approached separately for these clinical syndromes and there remains no treatment to slow, stop or prevent progression of clinical symptoms and development disability for people living with PD or DLB. Recent advances in biomarker tools, however, have paved new paths for biologic definition and staging of PD and DLB under a shared research framework. Patient-centered research funding organizations see the opportunity for a novel biological staging system for PD and DLB to accelerate and increase success of therapeutic development for the patient communities they serve. Amid growing momentum in the field to develop biological definitions for these neurodegenerative diseases, 7 international nonprofit organizations focused on PD and DLB came together to drive multistakeholder discussion and input on a biological staging system for research. The impact of these convenings to date can be seen in changes incorporated into a proposed biological staging system and growing alignment within the field to rapidly apply new scientific knowledge and biomarker tools to inform clinical trial design. In working together, likeminded nonprofit partners who were initially catalyzed by the significant potential for a biological staging system also realized the power of a shared voice in calling the field to action and have since worked together to establish a coalition to advance precompetitive progress and reduce hurdles to developing better treatments for PD, DLB and biologically related disorders.

Loneliness, Dementia Status, and Their Association with All-Cause Mortality Among Older US Adults

Background

Loneliness, dementia, and mortality are interconnected.

Objective

We aimed at understanding mediating pathways and interactions between loneliness and dementia in relation to mortality risk.

Methods

The study tested bi-directional relationships between dementia, loneliness, and mortality, by examining both interactions and mediating effects in a large sample of older US adults participating in the nationally representative Health and Retirement Study. Out of≤6,468 older participants selected in 2010, with mean baseline age of 78.3 years and a follow-up time up to the end of 2020, 3,298 died at a rate of 64 per 1,000 person-years (P-Y). Cox proportional hazards and four-way decomposition models were used.

Results

Algorithmically defined dementia status (yes versus no) was consistently linked with a more than two-fold increase in mortality risk. Dementia status and Ln(odds of dementia) were strongly related with mortality risk across tertiles of loneliness score. Loneliness z-score was also linked to an elevated risk of all-cause mortality regardless of age, sex, or race or ethnicity, and its total effect (TE) on mortality was partially mediated by Ln(odds of dementia), z-scored, (≤40% of the TE was a pure indirect effect). Conversely, a small proportion (<5%) of the TE of Ln(odds of dementia), z-scored, on mortality risk was explained by the loneliness z-score.

Conclusions

In sum, dementia was positively associated with all-cause mortality risk, in similar fashion across loneliness score tertiles, while loneliness was associated with mortality risk. TE of loneliness on mortality risk was partially mediated by dementia odds in reduced models.

Cancer drugs with high repositioning potential for Alzheimer's disease

INTRODUCTION

Despite the recent full FDA approval of lecanemab, there is currently no disease modifying therapy (DMT) that can efficiently slow down the progression of Alzheimer's disease (AD) in the general population. This statement emphasizes the need to identify novel DMTs in the shortest time possible to prevent a global epidemic of AD cases as the world population experiences an increase in lifespan.

AREAS COVERED

Here, we review several classes of anti-cancer drugs that have been or are being investigated in Phase II/III clinical trials for AD, including immunomodulatory drugs, RXR agonists, sex hormone therapies, tyrosine kinase inhibitors, and monoclonal antibodies.

EXPERT OPINION

Given the overall course of brain pathologies during the progression of AD, we express a great enthusiasm for the repositioning of anti-cancer drugs as possible AD DMTs. We anticipate an increasing number of combinatorial therapy strategies to tackle AD symptoms and their underlying pathologies. However, we strongly encourage improvements in clinical trial study designs to better assess target engagement and possible efficacy over sufficient periods of drug exposure.