A large, naturalistic, community-based study of rivastigmine in mild-to-moderate AD: the EXTEND Study

The Cholinesterase Inhibitory Properties of Stephaniae Tetrandrae Radix

Stephaniae tetrandrae radix (STR) is a commonly used traditional Chinese medicine in alleviating edema by inducing diuresis. In the clinic, STR extracts or its components are widely used in the treatment of edema, dysuria, and rheumatism for the regulation of water metabolism. Furthermore, STR has been used in treating emotional problems for years by combining with other Chinese herbs. However, the material basis and mechanism of STR on the nervous system have not been revealed. Here, the main components of STR extracts with different extracting solvents were identified, including three major alkaloids, i.e., cyclanoline, fangchinoline, and tetrandrine. The cholinesterase inhibitory activity of STR extracts and its alkaloids was determined using the Ellman assay. Both cyclanoline and fangchinoline showed acetylcholinesterase (AChE) inhibitory activity, demonstrating noncompetitive enzyme inhibition. In contrast, tetrandrine did not show enzymatic inhibition. The synergism of STR alkaloids with huperzine A or donepezil was calculated by the median-effect principle. The drug combination of fangchinoline–huperzine A or donepezil synergistically inhibited AChE, having a combination index (CI) < 1 at F_a = 0.5. Furthermore, the molecular docking results showed that fangchinoline bound with AChE residues in the peripheral anionic site, and cyclanoline bound with AChE residues in the peripheral anionic site, anionic site, and catalytic site. In parallel, cyclanoline bound with butyrylcholinesterase (BChE) residues in the anionic site, catalytic site, and aromatic site. The results support that fangchinoline and cyclanoline, alkaloids derived from STR, could account for the anti-AChE function of STR. Thus, STR extract or its alkaloids may potentially be developed as a therapeutic strategy for Alzheimer’s patients.

Unmet Needs in Pharmacological Treatment of Apathy in Alzheimer's Disease: A Systematic Review

Background: Apathy is one of the most prevalent neuropsychiatric symptoms encountered in Alzheimer’s disease (AD) and may be an early sign in the development of dementia persisting over the disease course. It has been associated with poor disease outcome, impaired daily functioning, and significant caregiver distress. Early diagnosis and timely treatment of apathy in AD are of great importance. However, approved agents for apathy are still missing.

Methods: Within this context, we conducted an extensive electronic search in the databases included in the National Library of Medicine, PsychInfo, and Google Scholar for studies that have investigated the effect of pharmacological treatments in apathy in AD. There were no limitations regarding study design and all care settings were considered for inclusion. Structured measures for level of evidence and study quality were employed to evaluate the results.

Results: A total of 1,607 records were identified; 1,483 records remained after the removal of duplicates and were screened; 166 full-text articles were selected and assessed for eligibility and a remaining 90 unique studies and relevant reviews were included in the qualitative synthesis. Acetylcholinesterase inhibitors, gingko biloba, and methylphenidate were found to be successful in reducing apathy in patients with AD. Methodological heterogeneity in the studies and the small amount of studies where apathy was the primary outcome are limiting factors to assess for group effects.

Conclusions: Pharmacological treatment of apathy in AD is an underexplored field. Standardized and systematic efforts are needed to establish a possible treatment benefit. Elucidating the pathophysiology of apathy and its components or subtypes will inform disease models and mechanistic drug studies that can quantify a benefit from specific agents for specific AD groups.

Pharmacological and Nonpharmacological Treatment for Apathy in Alzheimer Disease : A systematic review across modalities

OBJECTIVE

Apathy is one of the most frequent neuropsychiatric symptoms encountered in Alzheimer disease (AD). Early diagnosis and timely treatment of apathy in AD seem to be of great importance, since apathy has been associated with poor disease outcome, reduced daily functioning, and caregiver distress.

DESIGN

Within this context, we conducted an extensive electronic search from the databases included in the National Library of Medicine as well as PsychInfo and Google Scholar for studies that have investigated the effect of pharmacological and nonpharmacological treatments of apathy in AD.

RESULTS

Acetylcholinesterase inhibitors, gingko biloba, methylphenidate, and a variety of nonpharmacological interventions were found to be successful in reducing apathy in patients with AD. Methodological heterogeneity of the studies and the small amount of studies where apathy was a primary outcome measure are limiting factors to evaluate for group effects.

CONCLUSION

Treatment of apathy in AD is a complicated and an underexplored field. Standardized and systematic efforts primarily focused on the study of apathy in AD may establish a benefit from individualized treatment for specific disease groups that would stem from a combination of both pharmacological and nonpharmacological interventions.

Efficacy of Galantamine on Cognition in Mild-to-Moderate Alzheimer's Dementia after Failure to Respond to Donepezil

OBJECTIVE

This study compares the efficacy of the cholinesterase inhibitor (ChEI) galantamine on cognition in patients with mild-to-moderate Alzheimer's dementia (AD) who were either naïve to ChEI drugs or who had failed a trial of the ChEI donepezil.

METHODS

Outpatients with AD were sequentially referred for screening and enrollment. Current outpatients who had taken donepezil for at least 6 months without demonstrated efficacy on cognition were switched to galantamine (switched group). New outpatients with no ChEI prescription history were classified as the naïve group and were given galantamine. The primary outcome measures for the between-group comparison were response rate on cognition at 26 and 52 weeks (categorical) and change on the Korean version of the Alzheimer's Disease Assessment Scale-cognitive subscale (dimensional). Secondary cognitive outcomes were measured using the subset of frontal executive function and the Korean Mini-Mental State Examination.

RESULTS

Seventy outpatients were enrolled and 66 were analyzed by Intent-to-treat (ITT). There were 42 cases in the naïve group and 24 in the switched group. Response rates did not differ at 26 weeks (71.4% naïve vs. 58.3% switched; p=0.277) or at 52 weeks (59.5% naïve vs. 41.6% switched; p=0.162). No significant differences were observed in the pattern of change over the 52 weeks on the primary and secondary cognitive scales.

CONCLUSION

As the efficacy of galantamine on cognition was not inferior in the switched group compared to that in the naïve group, switching ChEI drugs is clinically feasible for non-responding patients with mild-to-moderate AD.

Role of cognitive enhancer therapy in Alzheimer's disease with concomitant cerebral white matter disease: findings from a long-term naturalistic study

Background

Evidence is lacking for cognitive enhancer therapy in patients with Alzheimer’s disease (AD) and concomitant cerebrovascular disease (mixed AD) as such patients would have been excluded from clinical trials. Earlier studies of mixed AD have focused on large vessel cerebrovascular disease. The influence of small vessel cerebrovascular disease (svCVD) in the form of white matter hyperintensity (WMH) on treatment outcomes in mixed AD has not been addressed.

Objective

In this long-term naturalistic study, we evaluated the effectiveness of cognitive enhancers in patients with mixed AD with svCVD.

Methods

We conducted a retrospective analysis of a prospective clinical database from a memory clinic of a tertiary hospital. Magnetic resonance imaging WMH was used as a marker of svCVD. Demographic, cognitive, and treatment data were analysed. Linear mixed models with patient-specific random effects were used to evaluate cognitive outcomes over time while adjusting for confounders.

Results

Patients with mixed AD (n = 137) or AD without svCVD (pure AD) (n = 28) were studied over a median duration of 28.7 months. Patients with mixed AD had a higher prevalence of hypertension (62.8 vs. 35.7 %, p = 0.011). The majority (75.2 %) of the study sample were managed with monotherapy. Mini Mental State Examination (MMSE) scores decreased over time (−0.04, p = 0.007), and the decrease was similar for both diagnosis groups (−0.03, p = 0.246). Annual estimated mean MMSE decline was 0.84 for pure AD and 0.48 for mixed AD. Similar trends were observed with Montreal Cognitive Assessment (MoCA) scores, with annual estimated mean reduction of 0.72 and 0.48 for pure AD and mixed AD, respectively.

Conclusion

Cognitive enhancers are effective in slowing the rate of cognitive decline in patients with AD with svCVD. These findings would need to be confirmed in randomized clinical trials.

Effects and safety profile of betahistine in patients in the Russian contingent of OSVaLD, an open-label observational study in vestibular vertigo

BACKGROUND

We report here data from the >200 patients recruited in Russia to take part in OSVaLD, a 12-week, open-label, post-marketing surveillance study of the response to betahistine 48 mg/day in vertigo of peripheral vestibular origin carried out in a total of 13 countries.

METHODS

The primary efficacy endpoint was change in the Dizziness Handicap Inventory (DHI; 100-point scale). Changes in Hospital Anxiety and Depression Scale (HADS) and Medical Outcomes Study Short-Form 36, version 2 (SF-36v2(®)) scores were a priori secondary Outcomes.

RESULTS

Total DHI score improved by 43 points during betahistine treatment. This aggregate improvement was equally distributed across the three domains of the DHI (physical, emotional, and functional; P<0.0001 for main and subscore changes from baseline). Statistically significant improvements versus baseline were also observed in mean HADS scores for anxiety and depression (both P<0.0001), and in the Physical Component Summary and Mental Component Summary scores of the SF-36v2 (both P<0.0001 versus baseline). Only one suspected adverse drug reaction was recorded in the Russian safety population (n=204), indicating that betahistine was well tolerated in those patients.

CONCLUSION

Betahistine 48 mg/day was associated with clear improvements in well-configured and widely validated measures of health-related quality of life and an encouraging tolerability profile in patients in Russia who took part in OSVaLD.

Effects and tolerability of betahistine in patients with vestibular vertigo: results from the Romanian contingent of the OSVaLD study

Background and methods

An efficacy population of 245 patients with vertigo of peripheral vestibular origin was recruited in Romania as part of a 3-month multinational, post-marketing surveillance study of open-label betahistine 48 mg/day (OSVaLD). Endpoints were changes in the Dizziness Handicap Index (primary endpoint), Medical Outcome Study Short-Form 36 (SF-36v2^®), and the Hospital Anxiety and Depression Scale.

Results

During treatment, the total Dizziness Handicap Index score improved by 41 points (on a 100-point scale). Statistically significant improvements of 12–14 points were recorded in all three domains of the Dizziness Handicap Index scale (P<0.0001). Betahistine therapy was also accompanied by progressive improvements in mean Hospital Anxiety and Depression anxiety and depression scores (P<0.0001) and significant improvements in both the physical and mental component summary of the SF-36v2 (P<0.0001). Betahistine was well tolerated, with only one suspected adverse drug reaction recorded in the Romanian safety population (n=259).

Conclusion

Betahistine 48 mg/day was associated with improvements in multiple measures of health-related quality of life and had a good tolerability profile in these Romanian patients with recurrent peripheral vestibular vertigo.

Cognitive and affective changes in mild to moderate Alzheimer's disease patients undergoing switch of cholinesterase inhibitors: a 6-month observational study

Patients with Alzheimer’s disease after an initial response to cholinesterase inhibitors may complain a later lack of efficacy. This, in association with incident neuropsychiatric symptoms, may worsen patient quality of life. Thus, the switch to another cholinesterase inhibitor could represent a valid therapeutic strategy. The aim of this study was to investigate the effectiveness of the switch from one to another cholinesterase inhibitor on cognitive and affective symptoms in mild to moderate Alzheimer disease patients. Four hundred twenty-three subjects were included from the EVOLUTION study, an observational, longitudinal, multicentre study conducted on Alzheimer disease patients who switched to different cholinesterase inhibitor due either to lack/loss of efficacy or response, reduced tolerability or poor compliance. All patients underwent cognitive and neuropsychiatric assessments, carried out before the switch (baseline), and at 3 and 6-month follow-up. A significant effect of the different switch types was found on Mini-Mental State Examination score during time, with best effectiveness on mild Alzheimer’s disease patients switching from oral cholinesterase inhibitors to rivastigmine patch. Depressive symptoms, when measured using continuous Neuropsychiatric Inventory values, decreased significantly, while apathy symptoms remained stable over the 6 months after the switch. However, frequency of both depression and apathy, when measured categorically using Neuropsychiatric Inventory cut-off scores, did not change significantly during time. In mild to moderate Alzheimer disease patients with loss of efficacy and tolerability during cholinesterase inhibitor treatment, the switch to another cholinesterase inhibitor may represent an important option for slowing cognitive deterioration. The evidence of apathy stabilization and the positive tendency of depressive symptom improvement should definitively be confirmed in double-blind controlled studies.

Real-life effectiveness and tolerability of the rivastigmine transdermal patch in patients with mild-to-moderate Alzheimer's disease: the EMBRACE study

OBJECTIVE

To assess the real-life effectiveness and tolerability of the rivastigmine transdermal patch in patients with mild-to-moderate Alzheimer's disease (AD) in Canada.

RESEARCH DESIGN AND METHODS

Eighteen-month observational, prospective, multi-center, open-label study conducted on AD patients with Standardized Mini-Mental State Examination (SMMSE) score of 10-26 and Global Deterioration Scale (GDS) score of 4-6. Patients were treated with the rivastigmine transdermal patch (Exelon patch*) 5 cm² (4.6 mg/24 hours) or 10 cm² (9.5 mg/24 hours), once daily.

MAIN OUTCOME MEASURES

Primary outcome was change in SMMSE from baseline to 18 months. Secondary outcomes included change in SMMSE at 6 and 12 months and change in GDS, Assessment of Patient Ability (APA-C), Overall Patient Assessment Rating (OPAR), caregiver-reported compliance and treatment satisfaction at 6, 12, and 18 months.

RESULTS

Among the 1204 patients enrolled, 969 were included in the ITT analysis. Mean (SD) age was 80.2 (8.00) years, disease duration was 0.6 (1.26) years, 62.0% of patients were women, 80.4% were living in the community, and 69.3% were treatment naïve. Mean (SD) baseline SMMSE and GDS scores were 21.8 (3.98) and 4.2 (0.61), respectively. Over 18 months of treatment there were no clinically significant changes in SMMSE and GDS. The majority of patients showed improvement or no change in GDS, APA-C and OPAR over 18 months. The proportion with reported improvement in GDS, APA-C and OPAR was higher than the proportion that deteriorated. Compliance improved from baseline to 18 months and for 88.2% of patients caregivers preferred the transdermal patch to oral medications.

CONCLUSIONS

The rivastigmine transdermal patch is effective in maintaining cognitive function over 18 months of treatment in patients with mild-to-moderate AD. The safety profile was comparable to the data in the Canadian product monograph. Lack of a comparator group is a potential limitation of the study.

Pharmacologic treatment of apathy in dementia

Apathy in patients with dementia is common, underrecognized, and undertreated. We sought to improve understanding of the pharmacologic treatment of apathy in dementia by performing a systematic literature review of studies that used apathy outcome scales to document results of pharmacologic treatments for apathy. There is limited evidence of efficiency of pharmacotherapy for treatment of apathy in dementia. The best results were found for acetylcholinesterase inhibitors. There was some evidence of efficacy for memantine, but less evidence of efficacy for stimulants, calcium antagonists, and antipsychotics. There was no evidence to support the use of antidepressants or anticonvulsants. The research quality of studies was modest. Recommendations for standardizing research and for holistic evaluation and treatment are provided.

Switching cholinesterase inhibitors in older adults with dementia

BACKGROUND

Cholinesterase inhibitors (ChEIs) represent the mainstay of symptomatic treatment in Alzheimer's disease. Three medications belonging to this class are presently widely available. These agents differ in their individual mechanisms of action and pharmacokinetic properties. Switching ChEIs can be a reasonable option in cases of intolerance or lack of clinical benefit.

METHODS

A systematic literature search of switching ChEIs was conducted, and all studies specifically evaluating this issue were identified. Published consensus guidelines were also searched for recommendations on ChEI switching.

RESULTS

Eight clinical studies are summarized and discussed. All of these studies are open-label or retrospective and they cannot be readily compared because of heterogeneity in design, number of patients, agents used, and endpoints. Switching in most of these studies was done for both "lack of benefit" or "loss of response" after up to 29 months of treatment. Nevertheless, the majority of studies did not include individuals switched for lack of response after several years of treatment. Lack of satisfactory response or intolerance with the initial agent was not predictive of similar results with the second agent.

CONCLUSIONS

In light of these findings, we propose the following practical approach to switching ChEIs: (1) in the case of intolerance, switching to a second agent should be done only after the complete resolution of side-effects following discontinuation of the initial agent; (2) in the case of lack of efficacy, switching can be done overnight, with a quicker titration scheme thereafter; (3) switching ChEIs is not recommended in individuals who show loss of benefit several years after initiation of treatment.

Effects of rivastigmine on common symptomatology of Alzheimer's disease (EXPLORE)

OBJECTIVE

To evaluate, in a real-world clinical setting, the efficacy of rivastigmine in the management of six symptoms commonly associated with Alzheimer's disease (AD).

METHODS

This was a naturalistic, prospective, open-label, multi-centre, post-marketing, observational study. Data were collected by the participating study physicians at their practices across Canada. Subjects had a clinical diagnosis of mild-to-moderate AD and were prescribed rivastigmine by their treating physician. Efficacy was primarily evaluated by a physician-assessed, abbreviated Clinical Global Impression of Change (CGI-C) scale, focusing on six symptoms: attention, apathy, anxiety, agitation, irritability and sleep disturbance. Changes were assessed at months 3, 6 and 12. Several other patient-, physician- and caregiver-related assessments were also included.

RESULTS

A total of 4460 patients were recruited by 353 study physicians; 3800 were deemed evaluable, having taken at least one dose of rivastigmine and with at least one post-baseline assessment. At baseline, attention problems were present in 86.0% of evaluable patients, anxiety in 77.3%, apathy in 68.3%, irritability in 64.0%, agitation in 54.6% and sleep disturbance in 54.5%. At both month 6 and month 12, for each symptom, the percentage of patients experiencing an improvement was considerably larger than the percentage of patients who experienced symptom worsening. Among evaluable patients, the proportions improving vs. deteriorating at month 6 were 46.4 vs. 8.8% for attention; 42.8 vs. 7.2% for apathy; 41.1 vs. 9.4% for anxiety; 33.8 vs. 7.7% for agitation; 35.1 vs. 10.1% for irritability; and 30.8 vs. 5.4% for sleep disturbance.

LIMITATIONS

Open-label studies have an inherent potential for bias by both the caregiver and the physician.

CONCLUSIONS

This study demonstrates that a considerable proportion of rivastigmine-treated patients experience improvements on each of the six symptoms studied. These findings add further support to previous randomised, clinical studies showing benefit of rivastigmine in AD.

Peripheral cholinoceptor antagonist anisodamine counteracts cholinergic adverse effects and facilitates cognitive amelioration of rivastigmine

Rivastigmine is a potent acetyl- and butyrylcholinesterase inhibitor widely used for cognitive improvement in Alzheimer's disease (AD) therapy. However, dose-limiting adverse effects restrict its tolerability and clinical outcomes. This study explored new combined therapy, in which peripheral cholinergic adverse effects and central cognitive amelioration of rivastigmine were differentiated by a peripheral cholinoceptor antagonist anisodamine. The results demonstrated that rivastigmine (0.75 and 2.0 mg/kg) could significantly reverse the scopolamine-induced cognitive deficit in mice through passive avoidance test. Nevertheless, a high dose of rivastigmine (3.25 mg/kg) would compromise cognitive amelioration and produce obvious adverse effects, including hypersalivation, intestinal hyperperistalsis and muscle cramp. Interestingly, concomitant administration of anisodamine (10 mg/kg) effectively counteracted both the muscarinergic and nicotinergic adverse effects, while facilitating cognitive amelioration of rivastigmine (3.25 mg/kg). These findings provide an insight into the feasibility of combined therapy with cholinesterase inhibitors and peripheral cholinoceptor antagonists for the treatment of AD.

Behavioral effects of current Alzheimer's disease treatments: a descriptive review

BACKGROUND

Behavioral abnormalities and neuropsychiatric symptoms are common manifestations of Alzheimer's disease (AD). Many clinical trials of cholinesterase inhibitors (ChE-Is) and memantine have included behavioral measures as primary or secondary outcomes, and most have observed behavioral benefits in conjunction with treatment. The purpose of this review was to determine the frequency of positive behavioral outcomes in AD clinical trials and clinical reports, to determine the symptoms most responsive to antidementia agents, and to explore factors that correlate with negative outcomes in clinical trials of antidementia agents with regard to behavioral measures.

METHODS

We performed a computerized search of randomized clinical trials and open-label studies of ChE-Is and memantine for AD including a behavioral outcome measure. Studies involving 10 or more patients using therapeutic doses of the target agents and including a behavioral measure as a primary or secondary outcome were included in this review.

RESULTS

One hundred fifty-seven peer-reviewed articles and 68 publicly presented abstracts were identified in the literature search. Subsequent review established that 15 publications arising from 13 randomized, double-blind, placebo-controlled AD trials met the review inclusion criteria. Positive outcomes on behavioral measures were reported in 8 of 15 publications as a primary or secondary outcome. In most blinded AD clinical trials, behavioral measures were secondary outcomes. Mood symptoms and apathy have most commonly responded to ChE-Is, whereas memantine has been associated with a reduction in irritability and agitation. However, there is substantial variability among trials in terms of behavioral outcomes. Studies that assessed patients with more severe dementia, included patients with less severe behavioral disturbances at baseline, involved institutionalized patients, or were international in scope tended to have negative outcomes. In institutionalized patients there is commonly an improvement in the placebo group that confounds the observation of any drug-placebo difference.

CONCLUSIONS

Antidementia agents have been associated with beneficial behavioral outcomes in many randomized clinical trials and open-label studies. Most studies are not designed to test the psychotropic properties of antidementia drugs. Trials with negative behavioral outcomes are most likely to involve patients who are institutionalized and have few behavioral disturbances at baseline. Clinical trials designed to assess behavioral effects of antidementia agents should anticipate these factors.

EXACT: rivastigmine improves the high prevalence of attention deficits and mood and behaviour symptoms in Alzheimer's disease

The objective of this study was to investigate the impact of rivastigmine therapy on attention, apathy, anxiety and agitation in patients with mild-to-moderate Alzheimer's disease (AD) in a real-world clinical setting. Patients with mild-to-moderate AD were enrolled in the study by physicians across Canada. They were treated with open-label rivastigmine (dose at the discretion of the prescribing physicians) for a period of 6 months. Changes from baseline in attention, apathy, anxiety and agitation were assessed using an abbreviated Clinician's Global Impression of Change at 3- and 6-month visits. The Mini Mental State Examination (MMSE) was also used at these visits. Use and changes in use of psychotropic medications were recorded, as were changes in caregiver burden. Analyses of subgroups (outpatients vs. institutionalised patients) were also performed. A total of 2119 patients were enrolled in the study by 375 physicians. At baseline, 91% had deficits in attention, 85.4% had symptoms of anxiety, 78.5% exhibited apathy and 70.1% showed agitation. At 6 months, 67.5% of evaluable patients had improved on the symptom of attention, while 62.3%, 62.6% and 56.0% had improvements in anxiety, apathy and agitation respectively. The percentages with improvements were higher in the institutional subgroup than among outpatients. There was an overall mean improvement of 1.1 points on the MMSE at 6 months. Approximately four times as many caregivers reported a reduced burden than an increased burden at 6 months (40.3% vs. 10.3%). The majority of patients treated with rivastigmine experienced improvements in attention, anxiety, apathy and agitation. These real-life findings further demonstrate the proven efficacy of rivastigmine in patients with mild-to-moderate AD.