Initial cognitive response to cholinesterase inhibitors and subsequent long-term course in patients with mild Alzheimer's disease

Real-World Use of Symptomatic Treatments in Early Alzheimer's Disease

BACKGROUND

Alzheimer's disease (AD) is the most common type of dementia, causing progressive decline of memory, thinking, and behavior, impairing daily functioning. Early AD (eAD) includes mild cognitive impairment (MCI) due to AD and mild AD dementia.

OBJECTIVE

The aim of this study was to investigate symptomatic treatment prevalence and treatment patterns in eAD.

METHODS

Embase, MEDLINE, and EBM Reviews were searched in November 2021 for observational studies reporting symptomatic treatment patterns in eAD. The range of patients receiving treatment was collated. Risk of bias was assessed using the Joanna Briggs Institute (JBI) prevalence tool. Two independent reviewers screened the records, one performed data extraction and quality assessment while a second checked.

RESULTS

Twenty-one studies (prospective and retrospective cohorts, cross-sectional studies, and a survey) were included. Population size ranged from 23 to 2,028. Worldwide, 18 to 35% of patients diagnosed with MCI due to AD received any AChE inhibitor (three studies; n = 631), 7 to 8% memantine (two studies; n = 229), and 9% combination therapy (one study; n = 402). Patients receiving no treatment ranged from 41 to 54% (two studies; n = 733). Worldwide, in mild AD dementia patients, 13 to 89% received any AChE inhibitor (six studies; n = 3,715), 1 to 21% memantine (five studies, n = 3,527), and 0.4 to 39% combination therapy (four studies, n = 3,018). Patients receiving no treatment ranged from 9 to 26% (five studies, n = 4,073).

CONCLUSION

Limitations in reporting led to unclear risk of bias. The results reveal a pattern of use of symptomatic treatment in eAD beyond approved labels and highlights the opportunity for new consensus guidelines to inform clinical practice.

Predictors of response to acetylcholinesterase inhibitors in dementia: A systematic review

Background

The mainstay of therapy for many neurodegenerative dementias still relies on acetylcholinesterase inhibitors (AChEI); however, there is debate on various aspects of such treatment. A huge body of literature exists on possible predictors of response, but a comprehensive review is lacking. Therefore, our aim is to perform a systematic review of the predictors of response to AChEI in neurodegenerative dementias, providing a categorization and interpretation of the results.

Methods

We conducted a systematic review of the literature up to December 31st, 2021, searching five different databases and registers, including studies on rivastigmine, donepezil, and galantamine, with clearly defined criteria for the diagnosis of dementia and the response to AChEI therapy. Records were identified through the string: predict * AND respon * AND (acetylcholinesterase inhibitors OR donepezil OR rivastigmine OR galantamine). The results were presented narratively.

Results

We identified 1,994 records in five different databases; after exclusion of duplicates, title and abstract screening, and full-text retrieval, 122 studies were finally included.

Discussion

The studies show high heterogeneity in duration, response definition, drug dosage, and diagnostic criteria. Response to AChEI seems associated with correlates of cholinergic deficit (hallucinations, fluctuating cognition, substantia innominate atrophy) and preserved cholinergic neurons (faster alpha on REM sleep EEG, increased anterior frontal and parietal lobe perfusion after donepezil); white matter hyperintensities in the cholinergic pathways have shown inconsistent results. The K-variant of butyrylcholinesterase may correlate with better response in late stages of disease, while the role of polymorphisms in other genes involved in the cholinergic system is controversial. Factors related to drug availability may influence response; in particular, low serum albumin (for donepezil), CYP2D6 variants associated with reduced enzymatic activity and higher drug doses are the most consistent predictors, while AChEI concentration influence on clinical outcomes is debatable. Other predictors of response include faster disease progression, lower serum cholesterol, preserved medial temporal lobes, apathy, absence of concomitant diseases, and absence of antipsychotics. Short-term response may predict subsequent cognitive response, while higher education might correlate with short-term good response (months), and long-term poor response (years). Age, gender, baseline cognitive and functional levels, and APOE relationship with treatment outcome is controversial.

Does Treatment Response With Antidementia Drugs After 6 Months in Alzheimer's Disease Predict Long-term Treatment Outcome?

BACKGROUND

Alzheimer's disease (AD) is a chronic, progressive disorder that causes declines in cognitive and physical functions. This condition places severe burdens on families and caregivers. Delaying progressive declines in cognitive function and reducing their burden are thus important. Relationships between early treatment response and subsequent outcomes of schizophrenia and major depressive disorder have been reported. We thus aimed to investigate the relationships between treatment response to antidementia drugs in AD after 6 months (M) and subsequent outcomes.

METHODS

Eligible individuals comprised 194 patients diagnosed with presumed AD. Of these, 110 patients who received antidementia drugs for the first time and were assessed using the Mini-Mental State Examination (MMSE) at 6 M, 12 M, and 24 M were categorized as responders (n = 84) or nonresponders (n = 26). Responders were defined as showing a change in MMSE after 6 M the same as or lower than that in the natural course according to previously reported data.

RESULTS

No significant differences in baseline characteristics (age, sex, education, or comorbidities) were seen between groups. Mean MMSE score at baseline was significantly lower in responders (18.0) than in nonresponders (20.7; P = 0.008). Mean change from baseline MMSE was significantly smaller in responders than in nonresponders at both 12 M (-0.46 vs -2.5; P = 0.04) and 24 M (-0.78 vs -4.4; P = 0.001).

CONCLUSIONS

Treatment response with antidementia drugs after 6 M predicted better outcomes at 12 M and 24 M. Treatment response should be assessed every 6 M, and treatment should be reconsidered accordingly.

Long-Term Trazodone Use and Cognition: A Potential Therapeutic Role for Slow-Wave Sleep Enhancers

BACKGROUND

Recent studies reveal an association between slow-wave sleep (SWS), amyloid-β aggregation, and cognition.

OBJECTIVE

This retrospective study examines whether long-term use of trazodone, an SWS enhancer, is associated with delayed cognitive decline.

METHODS

We identified 25 regular trazodone users (mean age 75.4±7.5; 9 women, 16 men) who carried a diagnosis of Alzheimer's dementia, mild cognitive impairment, or normal cognition, and 25 propensity-matched trazodone non-users (mean age 74.5±8.0; 13 women, 12 men), accounting for age, sex, education, type of sleep deficit (hypersomnia, insomnia, parasomnia), diagnosis, and baseline Mini-Mental State Examination (MMSE). Longitudinal group differences in cognitive testing were evaluated through repeated measures tests over an average inter-evaluation interval of four years.

RESULTS

Trazodone non-users had 2.6-fold faster decline MMSE (primary outcome) compared to trazodone users, 0.27 (95% confidence interval [CI]: 0.07-0.48) versus 0.70 (95% CI: 0.50-0.90) points per year (p = 0.023). The observed effects were especially associated with subjective improvement of sleep complaints in post-hoc analyses (p = 0.0006). Secondary outcomes of other cognitive and functional scores had variable worsening in non-users and varied in significance when accounting for co-administered medications and multiple comparisons. Trazodone effects on MMSE remained significant within participants with AD-predicted pathology, with 2.4-fold faster decline in non-users (p = 0.038).

CONCLUSIONS

These results suggest an association between trazodone use and delayed cognitive decline, adding support for a potentially attractive and cost-effective intervention in dementia. Whether the observed relationship of trazodone to cognitive function is causal or an indirect marker of other effects, such as treated sleep disruption, and if such effects are mediated through SWS enhancement requires confirmation through prospective studies.

Extrapyramidal side effect of donepezil hydrochloride in an elderly patient: A case report

INTRODUCTION

Alzheimer disease (AD) is a neurodegenerative disease characterized by progressive cognitive dysfunction, which is mainly manifested as memory impairment and a reduced ability to self-care, often accompanied by neuropsychiatric and behavioral disorders. Donepezil is the second drug to be approved by the US FDA for the treatment of AD. Of the five FDA-approved drugs for AD treatment, donepezil is currently the most widely used. Here, we report an extrapyramidal adverse reaction to donepezil in an elderly patient with AD.

PATIENT CONCERNS

An 87-year-old woman presented with a 1-year history of forgetfulness that was aggravated since the past 2 months. She had a long-term history of multiple major conditions, including hypertension, diabetes, osteoporosis, and arterial plaques. Brain imaging showed age-related changes, and her Mini Mental State Examination score was 20. Other tests revealed no abnormalities apart from multiple thyroid nodules on ultrasonography.

DIAGNOSIS

She was diagnosed with AD, hypertension, type 2 diabetes mellitus, diabetic neuropathy, osteoporosis, carotid and lower-extremity arterial plaques, thyroid nodules.

INTERVENTIONS

She was treated with donepezil (5 mg/day), amlodipine besylate (5 mg/day), glimepiride (4 mg/day), methylcobalamin (1.5 mg/day), calcium carbonate D3 (600 mg/day), simvastatin (20 mg/day) and enteric-coated aspirin (100 mg/day).

OUTCOMES

Four days later, she experienced fatigue, panic, sweating, and one episode of vomiting. On the 5th day, she developed increased muscle tension, speech difficulty, and involuntary tremors. Imaging and blood tests revealed no obvious abnormality, and the patient was not receiving psychotropic drugs. An extrapyramidal adverse reaction to donepezil was considered, and the drug was discontinued, after which the symptoms gradually disappeared.

CONCLUSION

Serious adverse reactions to donepezil can occur in elderly patients, who typically require multiple medications for a variety of comorbidities. In particular, extrapyramidal reactions have occurred when donepezil is administered in combination with psychotropic drugs. However, in our patient, an extrapyramidal adverse reaction occurred in the absence of psychotropic drugs. Thus, clinicians must be aware of inter-individual differences in drug actions and possible serious adverse reactions, and carefully monitor these patients to ensure the timely detection of adverse events and their safe treatment.

Responder Analysis of a Multicomponent Non-Pharmacological Intervention (MAKS) for People With Cognitive Impairment in the German Day-Care Study (DeTaMAKS)

Background: Multicomponent non-pharmacological therapies have been shown to be effective at reducing cognitive symptoms and slowing deterioration in abilities to perform activities of daily living (ADL) in individuals with cognitive impairment. However, little is known about response rates and predictors of response. Methods: We used data from the German day-care study (DeTaMAKS; De = dementia, Ta = Tagespflege/day-care, M = motor stimulation, A = activities of daily living stimulation, K = k/cognitive stimulation, S = social stimulation; n = 362), which was based on a cluster-randomized trial of the non-pharmacological, multicomponent, anti-dementia MAKS therapy for people with cognitive impairment in day-care centers. We investigated response (defined as improvement or no deterioration) for three different response criteria: cognition via Mini-Mental State Examination (MMSE) score, ADL via Erlangen Test of Activities of Daily Living in Persons with Mild Dementia or Mild Cognitive Impairment (ETAM) score, and behavioral and psychological symptoms of dementia (BPSD) via Neuropsychiatric Inventory Questionnaire (NPI-Q) score. In addition, we calculated the number needed to treat (NTT) and response rates according to net gain analyses. Results: For all three criteria, the response rates were higher in the intervention group than in the control group (chi2 test: p = 0.058 to p = 0.003). Compared with non-responders, responders according to cognition had higher ETAM scores (= better ADL abilities) at baseline; responders according to ADL had lower ETAM scores (= poorer ADL abilities) at baseline; and responders according to BPSD had higher NPI-Q scores (= more BPSD) at baseline. Classification rates based on these predictors ranged from 60.6 to 68.3%. Discussion: The response rates to the non-pharmacological MAKS therapy were greater than those reported for anti-dementia drugs. There were only a few differences between responders and non-responders. Because of the low classification rates, these variables had only a small impact on response predictions. Therefore, there are no empirically substantiated selection criteria for the application of MAKS therapy in facilities. Clinical Trial Registration: www.ClinicalTrials.gov, identifier ISRCTN16412551.

The Contribution of Supplementary Tests in the Differential Diagnosis of Dementia

INTRODUCTION

Supplementary tests are part of the clinical approach to diagnose cognitive impairment. We aimed to determine the role of supplementary examinations, except for biomarkers, on diagnostic stability of dementia over time and to identify reversible dementias.

METHODS

We identified 432 patients with dementia who performed 2 clinical evaluations and the supplementary examinations recommended by the American Academy of Neurology in a follow-up period of 1 year.

RESULTS

In this sample, 110 (24.5%) patients changed their diagnosis at 1-year follow-up for the appearance of vascular cognitive impairment than the initial diagnosis, due to the neuroimaging. Concerning the reversible dementias, depression was the major differential diagnosis, detected in 13 (81%) of the 16 patients with cognitive improvement.

CONCLUSION

Therefore, regarding the supplementary examinations only neuroimaging and the depression triage were relevant for clinical practice regarding the differential diagnosis of dementia.

Dementia

Dementia is a syndrome seen most commonly in older people and characterized by a decline in cognitive performance which impacts on the person's ability to function. There are approximately 47 million people worldwide with dementia and there are 10 million new cases every year. It is a major cause of disability and dependence and impacts on the physical, psychologic, and social well-being of families and carers. Alzheimer's disease is the most common form of dementia. Gait and balance impairments are common in people with dementia and contribute to the significantly elevated risk of falls. Older people with dementia are at increased risk of injury, institutionalization, hospitalization, morbidity, and death after a fall. There is preliminary evidence, predominantly from relatively small studies, that falls and disability can be prevented in this population. However, more good-quality research is needed, both to provide some certainty around the existing evidence base as well as to explore alternate approaches to prevention, including combined cognitive-motor training and cognitive pharmacotherapy.

Clinical meaningfulness of Alzheimer's Disease Assessment Scale-Cognitive subscale change in relation to goal attainment in patients on cholinesterase inhibitors

INTRODUCTION

The clinical meaningfulness of Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) subscale change is disputed. We compared 2- to 4-point ADAS-Cog changes with changes in Goal Attainment Scaling (GAS) and everyday function across initial ADAS-Cog scores and treatment responses.

METHODS

This exploratory analysis evaluated mild-moderate Alzheimer's disease patients treated with donepezil (12 months) or galantamine (8 months). Clinical meaningfulness was defined as concomitant ADAS-Cog and GAS changes of ±3 points and/or functional improvement.

RESULTS

Patients with ≥3-point ADAS-Cog improvement significantly improved on GAS but not on standard tests of everyday function. ADAS-Cog "no change" (≤±3 points) was seen with mean GAS improvement. Initial ADAS-Cog improvement made endpoint improvement (ADAS-Cog 3 points and GAS 1 point) more likely (odds ratio = 6.9; 95% confidence interval = 2.5-19.5). In contrast, initial deterioration made endpoint improvement unlikely (0.33; 0.14-0.64).

DISCUSSION

ADAS-Cog improvement and no change were each associated with GAS improvement. Initial ADAS-Cog worsening was unlikely to result in later improvement.

CLINICAL TRIAL REGISTRATION NUMBER

ISRCTN26167328.

TREM2 variants and risk of Alzheimer's disease: a meta-analysis

Recent studies show that heterozygous variant of triggering receptor expressed on myeloid cells 2 (TREM2) increase the risk of Alzheimer's disease (AD) but with inconclusive results. Here, we conducted a meta-analysis to summarize and clarify the association between TREM2 variants and AD, and examined the relationship between TREM2 genetic variant and the etiology of AD. Relevant case-control studies were retrieved and collected according to established inclusion criteria. Odds ratio (OR) and 95% confidence interval (95% CI) were used to estimate the associations between three TREM2 variants (rs75932628, rs104894002, and rs143332484) and AD. In overall meta-analysis, the summary ORs for rs75932628, rs104894002, and rs143332484 were 2.70 [95% CI: 2.24, 3.24; P < 0.001], 7.21 (95% CI: 1.28, 40.78; P = 0.025), and 1.65 (95% CI: 1.24, 2.21; P = 0.001), respectively, indicating that the TREM2 rs75932628, rs104894002, and rs143332484 may contribute to AD risk. However, sensitivity analysis showed that the results of rs104894002 and rs143332484 should be interpreted with caution, and larger sample size, particularly in different ethnicities, are needed to validate the two variants. The current meta-analysis demonstrates that TREM2 is a candidate gene for AD susceptibility, and TREM2 variant rs75932628 may be a risk factor for AD.