Methodologic issues regarding outcome measures for clinical drug trials of psychiatric complications in dementia

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.

Living well with stroke: design and methods for a randomized controlled trial of a psychosocial behavioral intervention for poststroke depression

BACKGROUND

Depression is a sufficiently common sequela of a completed stroke to warrant intervention to improve mood, social, and functional outcome. Pharmacologic trials suggest short-term mood improvement from antidepressant treatment but no studies to date have determined whether these short-term gains can be enhanced and extended by a brief psychosocial/behavioral intervention delivered by advanced practice nurses. In addition, drug trials have not reported on functional outcomes such as limitations in ability, limitations in participation, and overall quality of survival. This randomized controlled trial was designed to evaluate the short- and long-term efficacy of a new brief psychosocial/behavioral intervention adjunctive to antidepressant treatment in reducing poststroke depression and improving functional outcomes.

METHODS

A total of 101 survivors of ischemic stroke with poststroke depression were randomly assigned to receive a brief psychosocial/behavioral intervention plus antidepressant or usual care, including antidepressants.

RESULTS

The primary outcome was reduction in depressive symptom severity (Hamilton Depression Rating Scale) at 12 months after stroke. Secondary outcomes were reductions in limitations in activity (Barthel Index), reduction in limitation in participation, and overall stroke impact (Stroke Impact Scale) at 6, 12, and 24 months poststroke. Factors influencing best response to psychosocial intervention were also explored.

CONCLUSION

This article provides detail on the design and treatment methods of this randomized trial in progress. Findings from this study provide important information regarding the long-term efficacy of such a behavioral intervention in reducing poststroke depression and subsequent impaired aspects of psychosocial and physical recovery.

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.

Nonpharmacologic treatment of behavioral disturbance in dementia

This article provides an overview of the current literature on non-pharmacologic treatment of behavioral problems in patients with dementia, and offers practical guidelines for healthcare professionals interested in using this approach with their patients. Because effective treatment begins with accurate assessment, we provide a brief discussion of the state-of-the-art in assessment of behavioral problems. The article discusses current trends in clinical care along with specific strategies for treating and preventing some of the most common and debilitating behavioral problems of dementia patients: depression, agitation/aggression, wandering, and sleep disturbance. Because caregivers are essential informants and participants in patient care, we conclude by addressing the role of the caregiver in nonpharmacologic treatment.

Understanding and managing behavioural symptoms in Alzheimer's disease and related dementias: focus on rivastigmine

Behavioural and psychological symptoms of dementia (BPSD) are among the most distressing manifestations of dementia and result in considerable social and economic costs. Practical, non-pharmacological approaches such as environmental and behavioural changes may provide some benefit for patients in managing mild BPSD. In addition, various pharmacological approaches to treatment have been employed, such as neuroleptics and atypical antipsychotics, which differ in neurochemical target and clinical effectiveness. Growing evidence suggests that the neurobiological basis of BPSD in Alzheimer's disease (AD) and related dementias is a loss of cholinergic neurones and a resultant decline in acetylcholine (ACh) in brain regions which regulate behavioural and emotional responses, such as the limbic system. This cholinergic deficit can be partly corrected by inhibiting cholinesterase enzymes (ChEs). Studies of ChE inhibitors have shown positive effects to improve or stabilise existing BPSD and delay the emergence of new behavioural symptoms. In placebo-controlled studies, donepezil has reported efficacy in non-institutionalised moderate to moderately severe patients over a period of 24 weeks, but has failed to demonstrate efficacy in mild to moderate AD and in institutionalised patients with severe disease. Galantamine has been shown to delay the onset of BPSD in mild to moderate AD patients in one placebo-controlled study, and improve BPSD in a similar study of patients with cerebrovascular disease or probable vascular dementia. Studies with rivastigmine have shown efficacy in placebo-controlled studies of mild to moderately severe AD and in patients with Lewy body variant AD. Institutionalised patients with severe disease also show symptomatic benefits in BPSD with rivastigmine, resulting in a reduction in concomitant psychoactive medication use. Symptom complexes responding to ChE inhibitors appear to differ - all agents improve apathy, depression and anxiety, while rivastigmine additionally improves hallucinations and delusions, possibility as a result of dual inhibition of acetylcholinesterase and butyrylcholinesterase. The presence of hallucinations has been shown to predict response to rivastigmine. Accumulating data from studies of ChE inhibitors suggest that early intervention and long-term treatment, in addition to providing cognitive benefits, improves BPSD and offers potential to enhance quality of life. Differences seen between the agents in terms of efficacy in BPSD, tolerability and safety profiles may be the result of differences in neuropharmacological profiles.

Neurobiological basis of behavioral and psychological symptoms in dementia of the Alzheimer type

Recent dementia studies indicate that behavioral and psychological symptoms of dementia (BPSD) are not merely an epiphenomenon of cognitive impairment, but could be attributed to specific biological brain dysfunction. We describe findings from different research modalities related with BPSD (psychopathological, neuropsychological, neurochemical, and psychophysiological strategies), and attempt to reconcile them into the more integrated form. Characteristics of delusions in dementia patients should be studied in more detail from a psychopathological aspect, aiming for the integration of psychopathology and neurobiology. Imperfect integration of memory function and cognitive function, assigned to the limbic systems and association areas, respectively, may result in BPSD. More intimate collaboration of psychopathological and neurobiological study would be fruitful to promote the research in psychological basis of BPSD. Neurochemical studies indicated that density of extracellular tangles and/or PHF-tau protein have relationships with delusion or misidentification. These changes in neurochemical parameters should be the key to understanding the pathogenesis of BPSD. More importantly, neurochemical and psychological study could be linked by the research in psychophysiology. Computer-assisted electroencephalogram analysis suggests that the right posterior hemisphere shows significant age-associated change earlier than the left in the elderly. Cerebral metabolic rate by positron emission tomography study indicates that paralimbic, left medial temporal, and left medial occipital area are involved in pathogenesis of BPSD in some dementia patients.

Assessment of agitation in Alzheimer's disease: the agitated behavior in dementia scale. Alzheimer's Disease Cooperative Study

OBJECTIVES

To develop and evaluate the psychometric properties of a new measure of agitation, the Agitated Behavior in Dementia scale (ABID). The ABID consists of 16 items designed specifically to evaluate frequency of and caregiver reaction to common agitated behaviors in community-residing dementia patients.

DESIGN

The ABID was administered at the baseline assessment of a multi-site controlled treatment study to reduce agitation in Alzheimer's Disease (AD). Reliability was assessed by evaluating internal consistency and test-retest correlations. Validity was assessed by examining correlations with other constructs, including demographics, cognitive status, and overall behavioral disturbance.

SETTING

Twenty-one sites across the US, comprising the Alzheimer's Disease Cooperative Study, contributed subjects to the investigation.

PARTICIPANTS

A total of 148 community-residing AD patients, living with a spouse or adult relative who acted as an informant. Mean age was 75 years, and mean Mini-Mental State Exam (MMSE) score was 13.

MEASUREMENTS

Cognitive status was assessed using the MMSE. Behavioral disturbance was assessed using the Behavior Rating Scale for Dementia of the Consortium to Establish a Registry for Alzheimer's Disease, the Revised Memory and Behavior Problems Checklist, and the Cohen-Mansfield Agitation Inventory.

RESULTS

Reliability of the ABID was excellent, with internal consistency of 0.70 and test-retest reliability of 0.60 to 0.73. Validity was confirmed by correlations with related measures and lack of correlation with unrelated constructs.

CONCLUSIONS

The ABID is brief, easy to administer, and provides objectively anchored observations of problems. It is a promising measure for studies of community-residing AD patients.

Assessing the impact of neuropsychiatric symptoms in Alzheimer's disease: the Neuropsychiatric Inventory Caregiver Distress Scale

OBJECTIVES

To develop an adjunct scale to the Neuropsychiatric Inventory (NPI) for assessing the impact of neuropsychiatric symptoms in Alzheimer's disease (AD) patients on caregiver distress.

DESIGN

Cross-sectional descriptive and correlational study.

SETTING

University out-patient memory disorders clinics.

PARTICIPANTS

Eighty-five AD subjects and their caregivers (54 spouses, 31 children).

MEASUREMENTS

The NPI and NPI Caregiver Distress Scale (NPI-D) were used to assess neuropsychiatric symptoms in AD patients and related caregiver distress, respectively. Criterion validity of the NPI-D was examined (N = 69) by comparison with an abridged version of the Relatives' Stress Scale (RSS'), a general measure of caregiver stress, using item clusters that had previously been correlated to behavioral disturbances in demented patients. Test-retest (n = 20) and inter-rater reliability (n = 16) of the NPI-D were also assessed.

RESULTS

Test-retest and interrater reliability of the NPI-D were both adequate. Overall, caregiver NPI-D distress ratings were correlated significantly with the RSS' (r = .60, P < .001). RSS' ratings correlated strongly with NPI scores (r = .64, P < .001), even after controlling for degree of cognitive impairment based on the Mini-Mental State Exam (MMSE) score (r = .61). MMSE scores showed a moderate correlation to RSS' ratings (-.30, P = .02), but this association was markedly attenuated when controlling for the degree of neuropsychiatric disturbance based on the NPI score (r = -. 14). NPI-D ratings for 9 of 10 NPI symptom domains correlated most strongly with either NPI symptom severity or total (frequency x severity) scores. Agitation, dysphoria, irritability, delusions, and apathy were the symptoms most often reported to be severely distressing to caregivers.

CONCLUSIONS

The NPI-D provides a reliable and valid measure of subjective caregiver distress in relation to neuropsychiatric symptoms measured by the NPI. Neuropsychiatric alterations are more strongly associated than cognitive symptoms to caregiver distress. The NPI-D may be useful in both clinical and research settings for assessing the contribution to caregiver distress of neuropsychiatric symptoms in AD patients.

A double-blind comparison of the efficacy and safely of paroxetine and imipramine in the treatment of depression with dementia

OBJECTIVES

To compare the efficacy of paroxetine and imipramine prospectively in patients with coexisting depression and dementia.

METHODS

An 8-week, double-blind, parallel group trial comparing paroxetine 20-40 mg/day with imipramine 50-100 mg/day in 198 patients aged 60 years or over with a Montgomery-Asberg Depression Rating Scale (MADRS) score > or = 20 and a Folstein mini-mental state evaluation score of 17-23 points after a 3- to 7-day placebo run-in period.

RESULTS

Both paroxetine and imipramine reduced the MADRS and the Clinical Global Impression (CGI) severity-of-illness and global improvement scores at weeks 2, 4, 8 and at endpoint, with no significant differences between treatment groups at any timepoint (MADRS, p > or = 0.368; cgi, p > or = 0.286). There was a statistically significant difference in favour of paroxetine at both the week 4 and week 8 timepoints (analysis of variance, p < or = 0.049) in the Cornell scale for depression in dementia: at endpoint there was no significant difference between treatments (p = 0.103). Treatment-emergent adverse experiences were reported by 51.5% (51/99) of patients treated with paroxetine and 50.5% (50/99) of patients treated with imipramine. Anticholinergic adverse experiences (paroxetine 6.1%; imipramine 13.1%) and serious non-fatal adverse experiences (paroxetine 4.0%; imipramine 8.1%) were reported by more patients in the imipramine group than in the paroxetine group.

CONCLUSIONS

Paroxetine and imipramine were both effective in the treatment of depression in elderly subjects with co-existing dementia, and no significant differences were detected between the groups. There were trends suggesting that paroxetine was better tolerated than imipramine in terms of anticholinergic adverse experiences and serious non-fatal adverse experiences.

Pharmacologic treatment of geriatric depression: key issues in interpreting the evidence

OBJECTIVE

A framework for critical appraisal of antidepressant trial literature involving geriatric subjects is presented. Among older adults, treatment decisions are complicated by comorbid medical and cognitive illness, the variable course of recovery, and the overlap of depressive symptoms with other disease symptoms. Consumers of the literature on competing antidepressant therapies for older adults must consider disease and population-specific outcome assessment issues.

DESIGN

An appraisal guide, adapted for geriatric depression, is developed from literature on methodological challenges of outcome assessment and published clinical trials comparing competing antidepressant therapies in older subjects.

CONCLUSIONS

The clinical utility of pharmacologic treatment of depression can be difficult to assess because depression scales in current use provide an important but limited perspective on treatment outcome and because the scales vary in actual content and ability to detect change. The use of indicators of function, independence, and self-perceived well-being as outcomes offers additional patient relevance and should be included. Key considerations involve (1) general characteristics: whether the depression outcome measure is valid and reproducible for the aged population under study, whether the outcome measure is sensitive to treatment-related change, and whether the time-frame of outcome assessment is appropriate for the treatment goal; (2) cognitive impairment: how subjects with dementia are assessed, and whether the impact of the intervention on caregivers and healthcare systems is considered as a relevant outcome; (3) pharmacologic issues: whether the comparator agent is a reasonable usual-care standard in the older adult and whether ascertainment for adverse effects is similar for all agents under study; and (4) broader general health status issues: whether functional or quality of life measures are used as outcome indicators.