Validation of brief cognitive tests in mild cognitive impairment, Alzheimer's disease and dementia with Lewy bodies.

Background It is estimated that 34 million people suffer from dementia, costing society US$422 billion each year. Alzheimer’s disease (AD) is the most common dementia and the global prevalence is predicted to increase to over 100 million people by the year 2050, with the greatest increase in developing countries. Therefore, inexpensive and efficient instruments are required for investigation and evaluation. Aim To evaluate the brief cognitive tests cube copying, clock drawing, the Mini-Mental State Examination (MMSE) and A Quick Test of Cognitive Speed (AQT) in the early diagnosis, treatment evaluation and differential diagnosis of dementias. Populations I. 85 patients with AD. II. 33 patients with dementia with Lewy bodies (DLB) and 66 with AD. III. 75 patients with AD. IV. 99 patients with mild cognitive impairment (MCI). Findings I. Cube copying was found useful for evaluating treatment with acetylcholinesterase inhibitors (AChEI) in patients with AD. II. Easy and quick interpretations of the MMSE, clock drawing and cube copying differentiated patients with DLB from patients with AD. III. AQT was twice as sensitive as the MMSE in detecting treatment response to AChEI in patients with AD. IV. The MMSE, AQT and clock drawing were as accurate as cerebrospinal fluid biomarkers (tau, Aβ42 and P-tau) in predicting development of AD and dementia in mild cognitive impairment during an average of five years. Conclusion This thesis has improved the validity of brief cognitive tests and contributed with results that can be clinically relevant for evaluating treatment of AD, differentiating DLB from AD, and predicting development of AD and other dementias

A Quick Test of cognitive speed is sensitive in detecting early treatment response in Alzheimer's disease

Introduction There is a great need for quick tests that identify treatment response in Alzheimer's disease (AD) to determine who benefits from the treatment. In this study, A Quick Test of cognitive speed (AQT) was compared with the mini-mental state examination (MMSE) in the evaluation of treatment outcome in AD. Methods 75 patients with mild to moderate AD at a memory clinic were assessed with AQT and the MMSE at a pretreatment visit, at baseline and after 8 weeks of treatment with cholinesterase inhibitors (ChEI) initiated at baseline. Changes in the mean test scores before and after treatment were compared, as well as the number of treatment responders detected by each test, according to a reliable change index (RCI). Results After 8 weeks of treatment, the AQT improvement, expressed as a percentage, was significantly greater than that of the MMSE (P = 0.026). According to the RCI, the cut-offs to define a responder were ≥16 seconds improvement on AQT and ≥3 points on the MMSE after 8 weeks. With these cut-offs, both tests falsely classified ≤5% as responders during the pretreatment period. After 8 weeks of treatment, AQT detected significantly more responders than the MMSE (34% compared with 17%; P = 0.024). After 6 months of treatment, the 8-week AQT responders still showed a significantly better treatment response than the AQT nonresponders (22.3 seconds in mean difference; P < 0.001). Conclusions AQT detects twice as many treatment responders as the MMSE. It seems that AQT can, already after 8 weeks, identify the AD patients who will continue to benefit from ChEI treatment

Association between Subcortical Lesions and Behavioral and Psychological Symptoms in Patients with Alzheimer's Disease.

Background/Aims: The most devastating features of Alz-heimer's disease (AD) are often the behavioral and psychological symptoms in dementia (BPSD). There is controversy as to whether subcortical lesions contribute to BPSD. The aim of this study was to examine the relationship between BPSD and subcortical lesions (white-matter lesions and lacunes) in AD. Methods: CT or MRI from 259 patients with mild-to-moderate AD were assessed with the Age-Related White Matter Changes scale. Linear measures of global and temporal atrophy and Mini-Mental State Examination scores were used to adjust for AD pathology and disease severity in logistic regression models with the BPSD items delusions, hallucinations, agitation, depression, anxiety, apathy and irritability. Results: Lacunes in the left basal ganglia were asso-ciated with delusions (OR 2.57, 95% CI 1.21-5.48) and hallucinations (OR 3.33, 95% CI 1.38-8.01) and lacunes in the right basal ganglia were associated with depression (OR 2.13, 95% CI 1.01-4.51). Conclusion: Lacunes in the basal ganglia resulted in a 2- to 3-fold increased risk of delusions, hallucinations and depression, when adjusting for cognition and atrophy. This suggests that basal ganglia lesions can contribute to BPSD in patients with AD, independently of the AD process

Comparison of Brief Cognitive Tests and CSF Biomarkers in Predicting Alzheimer’s Disease in Mild Cognitive Impairment: Six-Year Follow-Up Study

INTRODUCTION: Early identification of Alzheimer's disease (AD) is needed both for clinical trials and in clinical practice. In this study, we compared brief cognitive tests and cerebrospinal fluid (CSF) biomarkers in predicting conversion from mild cognitive impairment (MCI) to AD. METHODS: At a memory clinic, 133 patients with MCI were followed until development of dementia or until they had been stable over a mean period of 5.9 years (range 3.2-8.8 years). The Mini-Mental State Examination (MMSE), the clock drawing test, total tau, tau phosphorylated at Thr(181) (P-tau) and amyloid-β(1-42) (Aβ(42)) were assessed at baseline. RESULTS: During clinical follow-up, 47% remained cognitively stable and 53% developed dementia, with an incidence of 13.8%/year. In the group that developed dementia the prevalence of AD was 73.2%, vascular dementia 14.1%, dementia with Lewy bodies (DLB) 5.6%, progressive supranuclear palsy (PSP) 4.2%, semantic dementia 1.4% and dementia due to brain tumour 1.4%. When predicting subsequent development of AD among patients with MCI, the cognitive tests classified 81% of the cases correctly (AUC, 0.85; 95% CI, 0.77-0.90) and CSF biomarkers 83% (AUC, 0.89; 95% CI, 0.82-0.94). The combination of cognitive tests and CSF (AUC, 0.93; 95% CI 0.87 to 0.96) was significantly better than the cognitive tests (p = 0.01) and the CSF biomarkers (p = 0.04) alone when predicting AD. CONCLUSIONS: The MMSE and the clock drawing test were as accurate as CSF biomarkers in predicting future development of AD in patients with MCI. Combining both instruments provided significantly greater accuracy than cognitive tests or CSF biomarkers alone in predicting AD

Relating Experienced To Recalled breathlessness Observational (RETRO) study: a prospective study using a mobile phone application

Background: Breathlessness, the subjective sensation of breathing discomfort, is common and appears in the daily life of people with cardiorespiratory diseases. Physicians often rely on patient's history based on symptom recall. The relation between recalled and experienced breathlessness is still poorly understood. This paper presents the protocol for a study primarily aimed at evaluating the relationship between experienced breathlessness and (1) recalled breathlessness and (2) predicted future breathlessness. Methods: A mobile phone application will be used to collect data during daily life. Medically stable participants, >= 18 years of age with mean daily breathlessness of Numerical Rating Scale (NRS) 3/10 and able to use a mobile phone with internet will rate their breathlessness intensity on a 0-10 NRS prompted the user several times daily for 1 week. Participants will recall their breathlessness each day and week. Multivariable random effects regression models will be used for statistical analyses. Results: Results of the study will be submitted for publication in peer-reviewed journals and presented at relevant conferences. Discussion: This protocol describes a study aimed at investigating previously unknown areas of the experience and recall of breathlessness using a new method of data collection.Scientific Committee of Blekinge County Council; Swedish Society of Medicine; Swedish Respiratory Society; Swedish Heart-Lung Foundation; Wera and Emil Cornell Foundation; Swedish Society for Medical ResearchOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Cerebral inflammation is an underlying mechanism of early death in Alzheimer’s disease: a 13-year cause-specific multivariate mortality study

Introduction: Although Alzheimer’s disease (AD) is associated with early death, its life expectancy differs greatly between patients. A better understanding of this heterogeneity may reveal important disease mechanisms underlying the malignancy of AD. The aim of this study was to examine the relation between AD pathologies and early death in AD caused by dementia. Methods: At a memory clinic, 247 referred consecutive patients with AD were monitored during 12.6 ± 1.6 years. Multivariate Cox regression analyses were performed with baseline measures of amyloid beta (Aβ) pathology (APOE genotype, cerebrospinal fluid (CSF) Aβ42) tau pathology (CSF phosphorylated tau and total tau), cerebrovascular pathology (white-matter lesions and CSF/serum albumin ratio), neuroinflammatory pathology (CSF soluble vascular cell adhesion molecule-1, sVCAM-1), frontal, temporal, and central brain atrophies, global cognition, sex, and age. Comorbidities and medications also were analyzed. All continuous variables were transformed to z scores to compare hazard ratios (HRs) and 95% confidence intervals (CIs). Results: At follow-up, 89% of the patients had died. The mean survival time was 6.4 ± 3.0 years. The AD pathology that independently predicted an early death caused by dementia was cerebral inflammation (sVCAM-1; HR, 1.32; 95% CI, 1.07–1.64). Other independent predictors were lower global cognition (HR, 0.51; 95% CI, 0.43–0.61), frontal atrophy (HR, 1.38; 95% CI, 1.12–1.70), and medial temporal atrophy (HR, 1.23; 95% CI, 1.02–1.49). When examining death caused by dementia and related causes (vascular diseases and infections), age (HR, 1.23; 95% CI, 1.04–1.46) and cerebrovascular pathology (white-matter lesions: HR, 1.17; 95% CI, 1.01–1.36; and CSF/serum albumin ratio: HR, 1.16; 95% CI, 1.001–1.34) were also significant risk factors in addition to the previous variables. No comorbidity or medication was significant in the specific-cause models. Conclusions: This is the first study to link neuroinflammation independently to early death in AD and, hence, a rapidly progressing disease. Frontal and medial temporal atrophies and low cognition were also significant predictors. These are probably downstream biomarkers that reflect neuronal degeneration and late-stage disease. Our results suggest that inflammation, and not amyloid or tau pathology, is an independent underlying mechanism in the malignancy of AD

Detailed comparison of amyloid PET and CSF biomarkers for identifying early Alzheimer disease

Objective:To compare the diagnostic accuracy of CSF biomarkers and amyloid PET for diagnosing early-stage Alzheimer disease (AD).Methods:From the prospective, longitudinal BioFINDER study, we included 122 healthy elderly and 34 patients with mild cognitive impairment who developed AD dementia within 3 years (MCI-AD). -Amyloid (A) deposition in 9 brain regions was examined with [F-18]-flutemetamol PET. CSF was analyzed with INNOTEST and EUROIMMUN ELISAs. The results were replicated in 146 controls and 64 patients with MCI-AD from the Alzheimer's Disease Neuroimaging Initiative study.Results:The best CSF measures for identifying MCI-AD were A42/total tau (t-tau) and A42/hyperphosphorylated tau (p-tau) (area under the curve [AUC] 0.93-0.94). The best PET measures performed similarly (AUC 0.92-0.93; anterior cingulate, posterior cingulate/precuneus, and global neocortical uptake). CSF A42/t-tau and A42/p-tau performed better than CSF A42 and A42/40 (AUC difference 0.03-0.12, p < 0.05). Using nonoptimized cutoffs, CSF A42/t-tau had the highest accuracy of all CSF/PET biomarkers (sensitivity 97%, specificity 83%). The combination of CSF and PET was not better than using either biomarker separately.Conclusions:Amyloid PET and CSF biomarkers can identify early AD with high accuracy. There were no differences between the best CSF and PET measures and no improvement when combining them. Regional PET measures were not better than assessing the global A deposition. The results were replicated in an independent cohort using another CSF assay and PET tracer. The choice between CSF and amyloid PET biomarkers for identifying early AD can be based on availability, costs, and doctor/patient preferences since both have equally high diagnostic accuracy.Classification of evidence:This study provides Class III evidence that amyloid PET and CSF biomarkers identify early-stage AD equally accurately

Combining plasma phospho-tau and accessible measures to evaluate progression to Alzheimer’s dementia in mild cognitive impairment patients

BACKGROUND: Up to now, there are no clinically available minimally invasive biomarkers to accurately identify mild cognitive impairment (MCI) patients who are at greater risk to progress to Alzheimer's disease (AD) dementia. The recent advent of blood-based markers opens the door for more accessible biomarkers. We aimed to identify which combinations of AD related plasma biomarkers and other easily accessible assessments best predict progression to AD dementia in patients with mild cognitive impairment (MCI). METHODS: We included patients with amnestic MCI (n = 110) followed prospectively over 3 years to assess clinical status. Baseline plasma biomarkers (amyloid-β 42/40, phosphorylated tau217 [p-tau217], neurofilament light and glial fibrillary acidic protein), hippocampal volume, APOE genotype, and cognitive tests were available. Logistic regressions with conversion to amyloid-positive AD dementia within 3 years as outcome was used to evaluate the performance of different biomarkers measured at baseline, used alone or in combination. The first analyses included only the plasma biomarkers to determine the ones most related to AD dementia conversion. Second, hippocampal volume, APOE genotype and a brief cognitive composite score (mPACC) were combined with the best plasma biomarker. RESULTS: Of all plasma biomarker combinations, p-tau217 alone had the best performance for discriminating progression to AD dementia vs all other combinations (AUC 0.84, 95% CI 0.75-0.93). Next, combining p-tau217 with hippocampal volume, cognition, and APOE genotype provided the best discrimination between MCI progressors vs. non-progressors (AUC 0.89, 0.82-0.95). Across the few best models combining different markers, p-tau217 and cognition were consistently the main contributors. The most parsimonious model including p-tau217 and cognition had a similar model fit, but a slightly lower AUC (0.87, 0.79-0.95, p = 0.07). CONCLUSION: We identified that combining plasma p-tau217 and a brief cognitive composite score was strongly related to greater risk of progression to AD dementia in MCI patients, suggesting that these measures could be key components of future prognostic algorithms for early AD. TRIAL REGISTRATION: NCT01028053 , registered December 9, 2009

Cognitively Normal Women With Alzheimer’s Disease Proteinopathy Show Relative Preservation of Memory but Not of Hippocampal Volume

Background: We examined interactive effects of sex, diagnosis, and cerebrospinal fluid (CSF) amyloid beta/phosphorylated tau ratio (Aβ/P-tau) on verbal memory and hippocampal volumes. Methods: We assessed 682 participants (350 women) from BioFINDER (250 cognitively normal [CN]; and 432 symptomatic: 186 subjective cognitive decline [SCD], 246 mild cognitive impairment [MCI]). General linear models evaluated effects of Alzheimer’s disease (AD) proteinopathy (CSF Aß/p-tau ratio), diagnosis, and sex on verbal memory (ADAS-cog 10-word recall), semantic fluency (animal naming fluency), visuospatial skills (cube copy), processing speed/attention functions (Symbol Digit Modalities Test and Trail Making Part A), and hippocampal volumes. Results: Amyloid-positive (Aβ/P-tau+) CN women (women with preclinical AD) showed memory equivalent to amyloid-negative (Aβ/P-tau−) CN women. In contrast, Aβ/P-tau+ CN men (men with preclinical AD) showed poorer memory than Aβ/P-tau− CN men. Symptomatic groups showed no sex differences in effect of AD proteinopathy on memory. There was no interactive effect of sex, diagnosis, and Aβ/P-tau on other measures of cognition or on hippocampal volume. Conclusions: CN women show relatively preserved verbal memory, but not general cognitive reserve or preserved hippocampal volume in the presence of Aβ/P-tau+. Results have implications for diagnosing AD in women, and for clinical trials

Associations of CSF PDGFRβ With Aging, Blood-Brain Barrier Damage, Neuroinflammation, and Alzheimer Disease Pathologic Changes

BACKGROUND AND OBJECTIVES: Injured pericytes in the neurovascular unit release platelet-derived growth factor β (PDGFRβ) into the CSF. However, it is not clear how pericyte injury contributes to Alzheimer disease (AD)-related changes and blood-brain barrier (BBB) damage. We aimed to test whether CSF PDGFRβ was associated with different AD-associated and age-associated pathologic changes leading to dementia. METHODS: PDGFRβ was measured in the CSF of 771 participants with cognitively unimpaired (CU, n = 408), mild cognitive impairment (MCI, n = 175), and dementia (n = 188) from the Swedish BioFINDER-2 cohort. We then checked association with β-amyloid (Aβ)-PET and tau-PET standardized uptake value ratio, APOE ε4 genotype and MRI measurements of cortical thickness, white matter lesions (WMLs), and cerebral blood flow. We also analyzed the role of CSF PDGFRβ in the relationship between aging, BBB dysfunction (measured by CSF/plasma albumin ratio, QAlb), and neuroinflammation (i.e., CSF levels of YKL-40 and glial fibrillary acidic protein [GFAP], preferentially expressed in reactive astrocytes). RESULTS: The cohort had a mean age of 67 years (CU = 62.8, MCI = 69.9, dementia = 70.4), and 50.1% were male (CU = 46.6%, MCI = 53.7%, dementia = 54.3%). Higher CSF PDGFRβ concentrations were related to higher age (b = 19.1, β = 0.5, 95% CI 16-22.2, p 0.05). DISCUSSION: In summary, pericyte damage, reflected by CSF PDGFRβ, may be involved in age-related BBB disruption together with neuroinflammation, but is not related to Alzheimer-related pathologic changes