Mary Sano

A Controlled Trial of Selegiline, Alpha-Tocopherol, or Both as Treatment for Alzheimer's Disease

BACKGROUND There is evidence that medications or vitamins that increase the levels of brain catecholamines and protect against oxidative damage may reduce the neuronal damage and slow the progression of Alzheimers disease. METHODS We conducted a double-blind, placebo-controlled, randomized, multicenter trial in patients with Alzheimers disease of moderate severity. A total of 341 patients received the selective monoamine oxidase inhibitor selegiline (10 mg a day), alpha-tocopherol (vitamin E, 2000 IU a day), both selegiline and alpha-tocopherol, or placebo for two years. The primary outcome was the time to the occurrence of any of the following: death, institutionalization, loss of the ability to perform basic activities of daily living, or severe dementia (defined as a Clinical Dementia Rating of 3). RESULTS Despite random assignment, the baseline score on the Mini-Mental State Examination was higher in the placebo group than in the other three groups, and this variable was highly predictive of the primary outcome (P<0.001). In the unadjusted analyses, there was no statistically significant difference in the outcomes among the four groups. In analyses that included the base-line score on the Mini-Mental State Examination as a covariate, there were significant delays in the time to the primary outcome for the patients treated with selegiline (median time, 655 days; P=0.012), alpha-tocopherol (670 days, P=0.001) or combination therapy (585 days, P=0.049), as compared with the placebo group (440 days). CONCLUSIONS In patients with moderately severe impairment from Alzheimers disease, treatment with selegiline or alpha-tocopherol slows the progression of disease.

length of clinical trials of dementia drugs. Position paper from the International Working Group on Harmonization of Dementia Drug Guidelines.

We developed a set of informant-based items describing performance of activities of daily living (ADL) by patients with Alzheimers disease (AD) to identify which ADL are useful for assessment of patients in clinical trials. Evaluation of ADL is an important outcome measure in AD clinical trials. For clinical trial measurement, ADL should have broad applicability, good test-retest reliability, scaling to cover a range of performance, and sensitive to detect change in disease progression. A total of 45 ADL items developed from literature review and clinical experience were administered to informants of 242 AD patients and 64 elderly controls as part of the multicenter Alzheimers Disease Cooperative Study Instrument protocol. Half of the subjects were re-evaluated at 1 and 2 months and all at 6 and 12 months. Controls performed virtually all ADL items optimally at baseline and at 12 months. Among subjects with AD, 27 of the 45 ADL were widely applicable, i.e., performed at baseline or premorbidly by >90% of subjects; showed good test-retest reliability between baseline and 1 and 2 months; correlated with MMSE scores of AD patients cross-sectionally; and showed a decline in performance from baseline to 12 months in at least 20% of AD patients. ADL could be identified that capture change in functional ability in patients across the entire range of the MMSE. The remaining 18 ADL included several that may be useful for trials that target specific populations, e.g., women with AD. Because change on specific items depends on baseline MMSE, ADL evaluation should include items relevant to the severity of dementia of patients enrolled in a clinical trial …

Cognitive impairment after stroke: frequency, patterns, and relationship to functional abilities.

Cognitive function was examined in 227 patients three months after admission to hospital for ischaemic stroke, and in 240 stroke-free controls, using 17 scored items that assessed memory, orientation, verbal skills, visuospatial ability, abstract reasoning, and attentional skills. After adjusting for demographic factors with standardised residual scores in all subjects, the fifth percentile was used for controls as the criterion for failure on each item. The mean (SD) number of failed items was 3.4 (3.6) for patients with stroke and 0.8 (1.3) for controls (p < 0.001). Cognitive impairment, defined as failure on any four or more items, occurred in 35.2% of patients with stroke and 3.8% of controls (p < 0.001). Cognitive domains most likely to be defective in stroke compared with control subjects were memory, orientation, language, and attention. Among patients with stroke, cognitive impairment was most frequently associated with major cortical syndromes and with infarctions in the left anterior and posterior cerebral artery territories. Functional impairment was greater with cognitive impairment, and dependent living after discharge either at home or nursing home was more likely (55.0% with, v 32.7% without cognitive impairment, p = 0.001). In a logistic model examining the risks related to dependent living after stroke, cognitive impairment was a significant independent correlate (odds ratio, OR = 2.4), after adjusting for age (OR = 5.2, 80 + v 60-70 years) and physical impairment (OR = 3.7, Barthel index < or = 40 v > 40). It is concluded that cognitive impairment occurs frequently after stroke, commonly involving memory, orientation, language, and attention. The presence of cognitive impairment in patients with strike has important functional consequences, independent of the effects of physical impairment. Studies of stroke outcome and intervention should take into account both cognitive and physical impairments.

A randomized controlled trial of prednisone in Alzheimer's disease

To the Editor: We read with interest the article by Aisen et al.,1 who found that low doses of prednisone are not effective in AD. In the article, inflammatory processes are discussed in the pathophysiology of dementia, and corresponding therapeutic approaches are pursued. However, no clear clinical evidence for this exciting hypothesis has been established yet. To acquire information about the inflammatory activity of patients with expected dementia transferred to our ward, we investigated eosinophilic cationic protein (ECP) in serum. ECP is a sensitive marker of inflammatory processes and often used as a marker in clinical studies.2 We have 41 patients (mean age 73.8 years, SD 7.8; 7 men, 34 women) in our study. …

Effect of dimebon on cognition, activities of daily living, behaviour, and global function in patients with mild-to-moderate Alzheimer's disease: a randomised, double-blind, placebo-controlled study

BACKGROUND Although treatments for Alzheimers disease sometimes improve cognition, functional ability, or behaviour compared with baseline levels, such improvements are inconsistent across studies and measures, and effects diminish over time. More effective treatments are needed. We assessed the safety, tolerability, and efficacy of dimebon in the treatment of patients with mild-to-moderate Alzheimers disease. METHODS We enrolled 183 patients with mild-to-moderate Alzheimers disease (mini-mental state examination [MMSE] scores 10-24) at 11 sites in Russia. Patients were randomly assigned by a computer-generated randomisation scheme to receive oral dimebon, 20 mg three times a day (60 mg/day [n=89]), or matched placebo (n=94). Other antidementia drugs were not allowed. The primary outcome measure assessed cognition, the difference in mean change from baseline to week 26, or last completed observation on the cognitive subscale of the Alzheimers disease assessment scale (ADAS-cog). All patients and study personnel were blinded throughout the study. We compared dimebon with placebo with an intention-to-treat analysis, with last observation carried forward (ITT-LOCF) imputation. Analyses were repeated on the fully evaluable population, defined as all patients in the intention-to-treat population who had an ADAS-cog at week 26 and at least 80% compliance. 134 patients (68 in dimebon group, 66 in placebo group) enrolled in the 6-month blinded extension phase of the study. This trial is registered with Clinicaltrials.gov, number NCT00377715. FINDINGS 155 (85%) patients completed the trial (78 [88%] in dimebon group, 77 [82%] in placebo group). Treatment with dimebon resulted in significant benefits in ADAS-cog compared with placebo (ITT-LOCF) at week 26 (mean drug-placebo difference -4.0 [95% CI -5.73 to -2.28]; p<0.0001). Results of the ITT-LOCF and the evaluable population analyses were much the same for all measures. Patients given dimebon were significantly improved over baseline for ADAS-cog (mean difference -1.9 [-2.92 to -0.85]; p=0.0005). Dimebon was well tolerated: dry mouth and depressed mood or depression were the most common adverse events associated with dimebon (12 [14%] patients for each symptom by week 26). The percentage of patients who had adverse events in the two groups did not differ. INTERPRETATION Dimebon was safe, well tolerated, and significantly improved the clinical course of patients with mild-to-moderate Alzheimers disease.

Neuropsychological detection and characterization of preclinical Alzheimer's disease

Article abstract—We attempted to characterize the changes in cognition associated with the earliest, or preclinical, stages of Alzheimers disease (AD) by administering a comprehensive neuropsychological test battery to a group of initially nondemented older adults participating in a prospective epidemiologic study of dementia. Using Cox regression analyses, we examined the associations between baseline neuropsychological test scores and subsequent development of AD. Results confirmed preliminary findings that baseline scores on the Boston Naming Test, Immediate Recall on the Selective Reminding Test, and the Similarities subtest of the Wechsler Adult Intelligence Scale-Revised were significantly and independently associated with later diagnosis of AD. Analyses controlled for the effects of age, education, sex, and language of test administration. These results lend support to the notion of a preclinical phase of AD and indicate that this very early stage of AD is characterized by poor word-finding ability, abstract reasoning, and memory.

High-Dose B Vitamin Supplementation and Cognitive Decline in Alzheimer Disease: A Randomized Controlled Trial

CONTEXT Blood levels of homocysteine may be increased in Alzheimer disease (AD) and hyperhomocysteinemia may contribute to disease pathophysiology by vascular and direct neurotoxic mechanisms. Even in the absence of vitamin deficiency, homocysteine levels can be reduced by administration of high-dose supplements of folic acid and vitamins B(6) and B(12). Prior studies of B vitamins to reduce homocysteine in AD have not had sufficient size or duration to assess their effect on cognitive decline. OBJECTIVE To determine the efficacy and safety of B vitamin supplementation in the treatment of AD. DESIGN, SETTING, AND PATIENTS A multicenter, randomized, double-blind controlled clinical trial of high-dose folate, vitamin B(6), and vitamin B(12) supplementation in 409 (of 601 screened) individuals with mild to moderate AD (Mini-Mental State Examination scores between 14 and 26, inclusive) and normal folic acid, vitamin B(12), and homocysteine levels. The study was conducted between February 20, 2003, and December 15, 2006, at clinical research sites of the Alzheimer Disease Cooperative Study located throughout the United States. INTERVENTION Participants were randomly assigned to 2 groups of unequal size to increase enrollment (60% treated with high-dose supplements [5 mg/d of folate, 25 mg/d of vitamin B(6), 1 mg/d of vitamin B(12)] and 40% treated with identical placebo); duration of treatment was 18 months. MAIN OUTCOME MEASURE Change in the cognitive subscale of the Alzheimer Disease Assessment Scale (ADAS-cog). RESULTS A total of 340 participants (202 in active treatment group and 138 in placebo group) completed the trial while taking study medication. Although the vitamin supplement regimen was effective in reducing homocysteine levels (mean [SD], -2.42 [3.35] in active treatment group vs -0.86 [2.59] in placebo group; P < .001), it had no beneficial effect on the primary cognitive measure, rate of change in ADAS-cog score during 18 months (0.372 points per month for placebo group vs 0.401 points per month for active treatment group, P = .52; 95% confidence interval of rate difference, -0.06 to 0.12; based on the intention-to-treat generalized estimating equations model), or on any secondary measures. A higher quantity of adverse events involving depression was observed in the group treated with vitamin supplements. CONCLUSION This regimen of high-dose B vitamin supplements does not slow cognitive decline in individuals with mild to moderate AD. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00056225.

Development of cognitive instruments for use in clinical trials of antidementia drugs: Additions to the Alzheimer's disease assessment scale that broaden its scope

The cognitive assessment protocol of the Alzheimers Disease Cooperative Study (ADCS) was designed to evaluate the reliability and validity of cognitive assessment measures that might be valuable additions to the Alzheimers Disease Assessment Scale (ADAS) or other concise batteries used in antidementia drug trials. As part of an overall ADCS protocol to develop new instruments to be used in trials of treatments for Alzheimers disease (AD), patients with mild to moderate AD and cognitively normal elderly were administered a battery of five tests at least three times over 1 year. The tests included word list learning with delayed free recall, a recognition memory test for faces, a series of letter and digit cancellation tests to measure concentration, tests of praxis, and a series of maze completion tasks designed to assess planning and executive function. A version of the digit cancellation task was reliable and sensitive to a broad range of dementia severity so that it could provide a useful addition to the present version of the ADAS. Performance on the word learning task with delayed recall and a subset of the mazes task were impaired even in mild AD, so these tasks may be useful in trials involving mild or at-risk subjects. Performances on the facial recognition task and on the praxis tasks were not related to dementia severity, so these tasks would not be useful to evaluate treatments. Therefore, the major outcome of this investigation was the identification of some potential addtions to the present ADAS that extend both the cognitive domains and the range of symptom severity covered.

Cognitive function in nondemented older women who took estrogen after menopause

Investigations of the effects of estrogen replacement on cognitive function in healthy older women have yielded disparate results. We evaluated the relationship between a history of estrogen use and cognitive test performance in 727 women participating in a large community-based study. Participants were followed longitudinally for an average of 2.5 years. Estrogen use history was obtained at baseline. Standardized tests of memory, language, and abstract reasoning were administered at baseline and at follow-up. Results indicate that women who had used estrogen replacement scored significantly higher on cognitive testing at baseline than nonusers, and their performance on verbal memory improved slightly over time. The effect of estrogen on cognition was independent of age, education, ethnicity, and APOE genotype. Results suggest that estrogen replacement therapy may help to maintain cognitive function in nondemented postmenopausal women.

Common variants at 7p21 are associated with frontotemporal lobar degeneration with TDP-43 inclusions

Frontotemporal lobar degeneration (FTLD) is the second most common cause of presenile dementia. The predominant neuropathology is FTLD with TAR DNA-binding protein (TDP-43) inclusions (FTLD-TDP). FTLD-TDP is frequently familial, resulting from mutations in GRN (which encodes progranulin). We assembled an international collaboration to identify susceptibility loci for FTLD-TDP through a genome-wide association study of 515 individuals with FTLD-TDP. We found that FTLD-TDP associates with multiple SNPs mapping to a single linkage disequilibrium block on 7p21 that contains TMEM106B. Three SNPs retained genome-wide significance following Bonferroni correction (top SNP rs1990622, P = 1.08 × 10−11; odds ratio, minor allele (C) 0.61, 95% CI 0.53–0.71). The association replicated in 89 FTLD-TDP cases (rs1990622; P = 2 × 10−4). TMEM106B variants may confer risk of FTLD-TDP by increasing TMEM106B expression. TMEM106B variants also contribute to genetic risk for FTLD-TDP in individuals with mutations in GRN. Our data implicate variants in TMEM106B as a strong risk factor for FTLD-TDP, suggesting an underlying pathogenic mechanism.