Efficacy study of galantamine in possible Alzheimer's disease with or without cerebrovascular disease and vascular dementia in Thai patients: a slow-titration regimen

Current Pharmacotherapy and Multi-Target Approaches for Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by decreased synaptic transmission and cerebral atrophy with appearance of amyloid plaques and neurofibrillary tangles. Cognitive, functional, and behavioral alterations are commonly associated with the disease. Different pathophysiological pathways of AD have been proposed, some of which interact and influence one another. Current treatment for AD mainly involves the use of therapeutic agents to alleviate the symptoms in AD patients. The conventional single-target treatment approaches do not often cause the desired effect in the disease due to its multifactorial origin. Thus, multi-target strategies have since been undertaken, which aim to simultaneously target multiple targets involved in the development of AD. In this review, we provide an overview of the pathogenesis of AD and the current drug therapies for the disease. Additionally, rationales of the multi-target approaches and examples of multi-target drugs with pharmacological actions against AD are also discussed.

Effect of galantamine on attention in patients with Alzheimer's disease combined with cerebrovascular disease

AIM

Patients with Alzheimer's disease (AD) and cerebrovascular disease (CVD) show greater attentional deficits compared with AD patients without CVD. The aim of the present study was to investigate the effect of galantamine on attention in AD patients with CVD.

METHODS

In this open trial, 1512 patients with AD and CVD were recruited from 71 nationwide hospitals. The patients were given galantamine for 16 weeks. The primary outcome measure was the score on the Attention Questionnaire Scale (AQS), which measures the patients' attention in their daily lives. The secondary outcome measures were the scores on the Korean Mini-Mental State Examination, the Clinical Dementia Rating scale and the Global Deterioration Scale. Efficacy measures were calculated both at baseline and at the end of the treatment (week 16).

RESULTS

The responders rate on the AQS (change of the AQS from baseline >0) was 60.6% in AD patients with CVD. At the end of the treatment, both the AQS (15.0 ± 5.7 vs 16.3 ± 5.8, P < 0.001) and the Korean Mini-Mental State Examination scores (17.8 ± 4.8 vs 18.1 ± 5.1, P < 0.001) showed a significant improvement relative to the baseline performance. The Clinical Dementia Rating (1.25 ± 0.59 vs 1.22 ± 0.63 P = 0.025) and Global Deterioration Scale (3.82 ± 0.94 vs 3.76 ± 0.96, P = 0.002) scores also showed a significant decrease at the end of the treatment.

CONCLUSIONS

Galantamine is effective in improving attention in the daily lives of AD patients with CVD. Geriatr Gerontol Int 2017; 17: 1661-1668.

Examining the relationship between fatigue and cognition after stroke: A systematic review

Many stroke survivors experience fatigue, which is associated with a variety of factors including cognitive impairment. A few studies have examined the relationship between fatigue and cognition and have obtained conflicting results. The aim of the current study was to review the literature on the relationship between fatigue and cognition post-stroke. The following databases were searched: EMBASE (1980-February, 2014), PsycInfo (1806-February, 2014), CINAHL (1937-February, 2014), MEDLINE (1946-February, 2014), Ethos (1600-February, 2014) and DART (1999-February, 2014). Reference lists of relevant papers were screened and the citation indices of the included papers were searched using Web of Science. Studies were considered if they were on adult stroke patients and assessed the following: fatigue with quantitative measurements (≥ 3 response categories), cognition using objective measurements, and the relationship between fatigue and cognition. Overall, 413 papers were identified, of which 11 were included. Four studies found significant correlations between fatigue and memory, attention, speed of information processing and reading speed (r = -.36 to .46) whereas seven studies did not. Most studies had limitations; quality scores ranged from 9 to 14 on the Critical Appraisal Skills Programme Checklists. There was insufficient evidence to support or refute a relationship between fatigue and cognition post-stroke. More robust studies are needed.

Cognitive subdomain responses to galantamine in Alzheimer's disease

We investigated the effects of galantamine on cognitive subdomains in Alzheimer's disease (AD). Sixty-six patients with mild-to-moderate AD received open-label galantamine for 52 weeks. Cognitive function was measured using the Korean version of the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog-K). Response to galantamine was defined as "improvement or no deterioration" on the total scores of the ADAS-cog-K at 26 weeks. In the overall intent-to-treat sample, we found less cognitive decline during 26 and 52 weeks than the expected untreated course as predicted by Stern's equation. The operationally defined response rate at 26 weeks was 66.7%. The responders differed significantly from the nonresponders only in the memory and language domains but not in the domains of praxis or frontal/executive function or in secondary outcome measures of neuropsychiatric symptoms and activities of daily living. The subdomain analysis revealed an effect of galantamine on preservation of memory that was not apparent in the overall analysis. Failure to achieve responder status by 26 weeks was associated with no further possibility of response.

Disease progression meta-analysis model in Alzheimer's disease

BACKGROUND

Various authors have evaluated disease progression in Alzheimer's disease (AD), using patient data from individual clinical studies or pooled data across various trials. We conducted a systematic review of public data sources from 1990 to 2008 for all available AChE inhibitor studies, as well as clinical studies that evaluated the rate of deterioration in AD patients. Unique to this analysis, we developed a model based on literature data to describe the longitudinal response in the Alzheimer's Disease Assessment Scale-Cognitive (ADAS-cog) (change from baseline) in mild to moderate severity AD patients. The model was used to estimate disease progression for both placebo-treated patients and acetylcholinesterase (AChE)-inhibitor treated patients, and factors that affected disease progression.

METHODS

We collected 576 mean ADAS-cog changes from baseline data points of 52 trials, representing data from approximately 19,972 patients and more than 84,000 individual observations. The model described the rate of disease progression, the evident placebo effect, and the symptomatic effect of AChE-inhibitors. Baseline ADAS-cog, Mini-Mental State Examination score, age, and year of publication were tested as covariates.

RESULTS

The disease progression in mild to moderate AD patients across all available and relevant literature sources was estimated as 5.5 points per year. An Emax-type model best described the symptomatic drug effect of AChE inhibitors. The rate of disease progression (underlying disease progression) was no different between placebo and AChE-inhibitors groups. Baseline ADAS-cog is a significant covariate in disease progression. Baseline age was also tested as a covariate in the rate of disease progression, but the model was unable to describe any effects of age, likely because of the narrow distribution of mean age (literature-level analysis). There was no significant impact of publication year in the model.

CONCLUSIONS

Baseline ADAS-cog is a significant covariate affecting the rate of disease progression, and it describes or at least explains the different rates of deterioration evident in early or late stages of the disease. There was no significant impact of publication year in the model, suggesting that disease progression has not slowed in more recent trials.

Vasoreactivity induced by acetazolamide in patients with vascular dementia versus Alzheimer's disease

Acetazolamide vasoreactive test measures the increment of cerebral blood flow caused by compensatory vasodilatation ability of cerebral vessels which can be detected by transcranial Doppler ultrasound (TCD). This study aimed to compare the vascular reactivity in patients with vascular dementia (VaD) and Alzheimer's disease (AD).

PATIENTS AND METHODS

AD and VaD patients were recruited from the King Chulalongkorn Hospital Dementia Clinic. Thai Mini-mental State Examination was used for dementia detection. AD and possible VaD were defined by NINCDS/ADRDA and NINDS-AIREN criteria. Patients with extracranial carotid artery stenosis >50% and intracranial artery stenosis were excluded. TCD examination was performed using DWL Multi Dop-T. TCD was performed on MCA with insonation depth between 45 and 60 mm. Baseline end diastolic velocity (EDV), mid systolic velocity (MSV) and peak systolic velocity (PSV) were recorded. The velocities were obtained at 2, 5, 10 and 20 min after acetazolamide (1000 mg) injection. Mean baseline velocities (Vo) and velocities after acetazolamide injection (Va) were compared. Percentage of mean increment velocities was calculated {[(Va-Vo)/Vo]x100%}. Percentage differences of mean velocity change from Vo to Va at each recorded minute were compared. SPSS for Windows version 11.5.0. was used.

RESULT

Nine AD (5 males) and 9 VaD (6 males) were selected. Average ages of VaD and AD groups were 66.11 years-old and 75.22 years-old respectively. Mini-mental State Examination (MMSE) score in VaD and AD were 21.13 and 19.00. Mean baseline EDV and MSV in VaD were higher than AD but mean PSV was lower. The percentage of velocity change after acetazolamide in AD was higher than VaD at 5, 10 and 20 min. However the differences were not statistically significant.

CONCLUSION

Acetazolamide vasoreactive test using TCD may be the additional criterion to differentiate VaD from AD. Further study with more number of subjects for the study or higher dose of acetazolamide may be needed to reveal the significant difference of vasoreactive response between VaD and AD patients.

Galantamine for the treatment of BPSD in Thai patients with possible Alzheimer's disease with or without cerebrovascular disease

OBJECTIVES

This study was to investigate an efficacy of galantamine in treatment of behavioral and psychological symptoms of dementia in Thai elderly who suffered from possible Alzheimer's disease (AD) with or without cerebrovascular disease and vascular dementia.

METHODS

A 6-month, multicenter, open-label, uncontrolled trial was undertaken in 75 patients. Eligible patients received an initial galantamine dose of 8 mg/dayand escalated over 5 to 8 weeks to maintenance doses of 16 or 24 mg/day. The behavioral response was assessed as an intention-to-treat analysis using the Behavioral Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD).

RESULTS

Galantamine improved behavioral and psychological symptoms of dementia (P < .05 vs baseline) over the 24 weeks of treatment. BEHAVE-AD score was significantly improved from baseline in paranoid and delusion ideation, diurnal rhythm disturbances, anxieties, and phobias.

CONCLUSIONS

Galantamine may be a well-tolerated and effective treatment option for improving psychotic, behavioral, and psychological symptoms in Thai elderly with possible AD with or without cerebrovascular disease and vascular dementia.

The effects of omega-3 fatty acids monotherapy in Alzheimer's disease and mild cognitive impairment: a preliminary randomized double-blind placebo-controlled study

A 24-week, randomized, double-blind placebo-controlled study was carried out to test the feasibility of using omega-3 polyunsaturated fatty acids (PUFAs) monotherapy in people with cognitive impairment and to explore its effects on cognitive function and general clinical condition in these participants. Twenty three participants with mild or moderate Alzheimer's disease and twenty three with mild cognitive impairment were randomized to receive omega-3 PUFAs 1.8 g/day or placebo (olive oil). The data of 35 (76%) participants with at least one post-treatment visit was analyzed. There were no severe adverse effects in either group and it suggests that omega-3 PUFAs were well tolerable in this population. The treatment group showed better improvement on the Clinician's Interview-Based Impression of Change Scale (CIBIC-plus) than those in the placebo group over the 24 week follow-up (p=0.008). There was no significant difference in the cognitive portion of the Alzheimer's Disease Assessment Scale (ADAS-cog) change during follow-up in these two groups. However, the omega-3 fatty acids group showed significant improvement in ADAS-cog compared to the placebo group in participants with mild cognitive impairment (p=0.03), which was not observed in those with Alzheimer's disease. Higher proportions of eicosapentaenoic acid on RBC membranes were also associated with better cognitive outcome (p=0.003). Further studies should be considered with a larger-sample size, diet registration, higher dosages, comparisons between different combinations of PUFAs, and greater homogeneity of participants, especially those with mild Alzheimer's disease and mild cognitive impairment.

A 2-year open-label study of galantamine therapy in Chinese Alzheimer's disease patients in Hong Kong

There was no long-term clinical study on galantamine in Alzheimer's disease (AD) in the Asian population. The objectives of this study were to evaluate the efficacy of galantamine on cognitive function, daily functioning, behavioural symptoms and its safety in Chinese AD patients. This was a 2-year open-label clinical trial. The inclusion criteria were patients with probable AD by the NINCDS-ADRDA criteria. A historical control group (n = 19) of AD patients with no galantamine or other cholinesterase inhibitor therapy was employed. In the galantamine group, 33 and 32 subjects had completed a 1-year and 2-year follow up, respectively. Within the galantamine group and at a 6-month follow up, the Alzheimer's Disease Assessment Scale Cognitive Subscale (ADAS-cog score) showed an improvement of 2.9 +/- 1.18 (p = 0.019, paired t-test) but remained the same at 1 and 2 years. The Alzheimer's Disease Cooperative Study-Activities of Daily Living Inventory (ADCS-ADL) deteriorated by 4.31 +/- 2.06 (p = 0.044, paired t-test) at 6 months but showed no significant decline at 1 and 2 years vs. baseline. The Neuropsychiatric Inventory (NPI) score also showed a significant deterioration of 5 +/- 1.99 (p = 0.017, paired t-test) at 6 months, 8.06 +/- 1.97 (p < 0.001, paired t-test) at 1 year and 7.31 +/- 1.76 at 2 years. Comparison between the two groups showed a statistically significant improvement in the 1-year ADAS-cog score but decline in the NPI score in the galantamine vs. control groups. Adverse effects were commonly mild. In Chinese mild-moderate AD patients, galantamine showed beneficial effects mainly on the cognitive function.