Cognitive intervention therapy as treatment for behaviour disorders in Alzheimer disease: evidence on efficacy and neurobiological correlations

Functional Therapeutic Strategies Used in Different Stages of Alzheimer's Disease-A Systematic Review

As Alzheimer's disease develops, the central nervous system is gradually damaged. It is manifested by progressive dementia and the appearance of neurological and extrapyramidal symptoms that impair everyday functioning. The aim of the study was to evaluate the influence of physical exercise on cognitive and motor functions in various stages of Alzheimer's disease. Methods: Four databases (PubMed, Scopus, Ovid, and Cochrane Library) were searched for relevant papers published between 2012 and May 2022. The works were assessed in terms of the adopted inclusion criteria. The measures of the results were changed in the parameters assessing motor and cognitive functions. Methodological quality was assessed using the Cochrane Collaboration. This review was recorded with the Cochrane Library: CRD42022340496. The results of the database search showed 302 articles, 12 of which were included in the review. All studies have shown a significant positive effect on improving cognitive and motor functions. This systematic review revealed a beneficial effect in improving cognitive and motor functions after the application of various kinds of activities, especially in the early and mild stages of Alzheimer's disease.

The Relationship Between Anxiety and Alzheimer's Disease

Although Alzheimer’s disease (AD) is primarily a neurocognitive disorder, it also results in prominent neuropsychiatric symptoms (NPS). Much literature has investigated the NPS of apathy and depression in association with AD, but relatively less is known regarding anxiety, the third most common NPS in this disorder. The prevalence of anxiety symptoms in AD is about 40%, and it can be a prelude of AD. Anxiety can be especially present among patients with mild cognitive impairment, mild dementia, or early-onset forms of the disease, and can promote progression or conversion to Alzheimer’s clinical syndrome. A number of studies have established that anxiety is associated with positive amyloid scans, mesial temporal changes with atrophy and hypometabolism in the entorhinal region, and neurofibrillary tangles present on pathological examination of this region. In addition to psychosocial factors, proposed neurobiological mechanisms for increased anxiety in AD include decreased sensorimotor gating, relatively increased activation of amygdalae or the Salience Network, and the presence of comorbid pathology, particularly Lewy bodies. Having management strategies for anxiety in patients with AD is important as anxiety can worsen cognitive deficits. Interventions involve psychological support, behavioral management, and the judicious use of the psychiatric armamentarium of medications.

Medial temporal lobe atrophy is independently associated with behavioural and psychological symptoms in Alzheimer's disease

AIM

Evidence describing the contribution of cerebral white matter disease and medial temporal atrophy (MTA) to behavioural and psychological symptoms of dementia (BPSD) has been conflicting. The aim of this study was to assess the relationship of white matter hyperintensities (WMH) and MTA observed on magnetic resonance imaging with BPSD among patients with Alzheimer's disease.

METHODS

In a cross-sectional study of a prospective cohort of patients attending a memory clinic, 46 patients with probable Alzheimer's disease (mean age: 72.38 ± 7.05 years) were studied. Sociodemographic, cognitive, and BPSD data were collected. BPSD were assessed using the Neuropsychiatric Inventory. Magnetic resonance imaging, WMH, and MTA were rated using the Scheltens scales for the assessment of signal hyperintensities and atrophy of medial temporal lobes. For multivariate analysis, two binary logistic regression analyses were carried out, with presence or absence of each BPSD as the dependent variable and with WMH or MTA as the predictor variable. Results of the logistic regression were analyzed to see if the significance of the WMH or MTA score was maintained in a model that factored in other possible confounding variables identified in univariate analysis.

RESULTS

The results of binary logistic regression analysis showed that in models that accounted for confounding variables, increased total MTA was significantly associated with apathy (odds ratio = 1.605, adjusted P = 0.042) and disinhibition (odds ratio = 0.607, adjusted P = 0.042). WMH measures did not significantly predict any BPSD item.

CONCLUSIONS

These findings indicate that MTA potentially contributes to the aetiology of BPSD, and they provide evidence to support the hypothesis that Alzheimer's disease pathology itself can contribute to BPSD.

Neurostimulation Combined With Cognitive Intervention in Alzheimer's Disease (NeuroAD): Study Protocol of Double-Blind, Randomized, Factorial Clinical Trial

Despite advances in the treatment of Alzheimer’s disease (AD), there is currently no prospect of a cure, and evidence shows that multifactorial interventions can benefit patients. A promising therapeutic alternative is the use of transcranial direct current stimulation (tDCS) simultaneously with cognitive intervention. The combination of these non-pharmacological techniques is apparently a safe and accessible approach. This study protocol aims to compare the efficacy of tDCS and cognitive intervention in a double-blind, randomized and factorial clinical trial. One hundred participants diagnosed with mild-stage AD will be randomized to receive both tDCS and cognitive intervention, tDCS, cognitive intervention, or placebo. The treatment will last 8 weeks, with a 12-month follow-up. The primary outcome will be the improvement of global cognitive functions, evaluated by the AD Assessment Scale, cognitive subscale (ADAS-Cog). The secondary outcomes will include measures of functional, affective, and behavioral components, as well as a neurophysiological marker (Brain-derived neurotrophic factor, BDNF). This study will enable us to assess, both in the short and long term, whether tDCS is more effective than the placebo and to examine the effects of combined therapy (tDCS and cognitive intervention) and isolated treatments (tDCS vs. cognitive intervention) on patients with AD.

Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT02772185—May 5, 2016.

Tertiary amine derivatives of chlorochalcone as acetylcholinesterase (AChE) and buthylcholinesterase (BuChE) inhibitors: the influence of chlorine, alkyl amine side chain and α,β-unsaturated ketone group

A new series of tertiary amine derivatives of chlorochalcone (4a∼4l) were designed, synthesized and evaluated for the effect on acetylcholinesterase (AChE) and buthylcholinesterase (BuChE). The results indicated that all compounds revealed moderate or potent inhibitory activity against AChE, and some possessed high selectivity for AChE over BuChE. The structure–activity investigation showed that the substituted position of chlorine significantly influenced the activity and selectivity. The alteration of tertiary amine group also leads to obvious change in bioactivity. Among them, IC₅₀ of compound 4l against AChE was 0.17 ± 0.06 µmol/L, and the selectivity was 667.2 fold for AChE over BuChE. Molecular docking and enzyme kinetic study on compound 4l suggested that it simultaneously binds to the catalytic active site (CAS) and peripheral anionic site (PAS) of AChE. Further study showed that the pyrazoline derivatives synthesized from chlorochalcones had weaker activity and lower selectivity in inhibiting AChE compared to that of chlorochalcone derivatives.