Use of Alzheimer's Disease Cerebrospinal Fluid Biomarkers in A Tertiary Care Memory Clinic.

INTRODUCTION: Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers are promising tools to help identify the underlying pathology of neurocognitive disorders. In this manuscript, we report our experience with AD CSF biomarkers in 262 consecutive patients in a tertiary care memory clinic. METHODS: We retrospectively reviewed 262 consecutive patients who underwent lumbar puncture (LP) and CSF measurement of AD biomarkers (Aß1-42, total tau or t-tau, and p-tau181). We studied the safety of the procedure and its impact on patient's diagnosis and management. RESULTS: The LP allowed to identify underlying AD pathology in 72 of the 121 patients (59%) with early onset amnestic mild cognitive impairment (aMCI) with a high probability of progression to AD; to distinguish the behavioral/dysexecutive variant of AD from the behavioral variant of frontotemporal dementia (bvFTD) in 25 of the 45 patients (55%) with an atypical neurobehavioral profile; to identify AD as the underlying pathology in 15 of the 27 patients (55%) with atypical or unclassifiable primary progressive aphasia (PPA); and to distinguish AD from other disorders in 9 of the 29 patients (31%) with psychiatric differential diagnoses and 19 of the 40 patients (47%) with lesional differential diagnoses (normal pressure hydrocephalus, encephalitis, prion disease, etc.). No major complications occurred following the LP. INTERPRETATION: Our results suggest that CSF analysis is a safe and effective diagnostic tool in select patients with neurocognitive disorders. We advocate for a wider use of this biomarker in tertiary care memory clinics in Canada.

The Dépistage Cognitif de Québec: A New Clinician's Tool for Early Recognition of Atypical Dementia.

INTRODUCTION: Early recognition of atypical dementia remains challenging partly because of lack of cognitive screening instruments precisely tailored for this purpose. METHODS: We assessed the validity and reliability of the Dépistage Cognitif de Québec (DCQ; www.dcqtest.org), a newly developed cognitive screening test, to detect atypical dementia using a multicenter cohort of 628 participants. Sensitivity and specificity were compared to the Montreal Cognitive Assessment (MoCA). A predictive diagnostic algorithm for atypical dementia was determined using classification tree analysis. RESULTS: The DCQ showed excellent psychometric properties. It was significantly more accurate than the MoCA to detect atypical dementia. All correlations between DCQ indexes and standard neuropsychological measures were significant. A statistical model distinguished typical from atypical dementia with a predictive power of 79%. DISCUSSION: The DCQ is a better tool to detect atypical dementia than standard cognitive screening tests. Expanding the clinician's tool kit with the DCQ could reduce missed/delayed identification of atypical dementia and accelerate therapeutic intervention.

Exploration of verbal repetition in people with dementia using an online symptom-tracking tool.

BACKGROUND: Online tools can be used by people with dementia and their caregivers to self-identify and track troubling symptoms, such as verbal repetition. We aimed to explore verbal repetition behaviors in people with dementia. METHODS: Participants were recruited via an online resource for people with dementia and their caregivers. Respondents were instructed to complete information about symptoms that are most important to them for tracking over time. In this cross-sectional study, we analyzed data pertaining to individuals with dementia who had at least three symptoms selected for tracking. RESULTS: Of the 3,573 participants who began a user profile, 1,707 fulfilled criteria for analysis. Verbal repetition was identified as a treatment target in 807 respondents (47.3%). Verbal repetition was more frequent in individuals with mild dementia compared to those with moderate and severe dementia (57.2% vs. 36.0% and 39.9%, p < 0.01) and in those with Alzheimer's disease versus other dementias (65.2% vs. 29.7%, p < 0.001). Repetitive questioning was the most frequent type of verbal repetition (90.5% of individuals with verbal repetition). Verbal repetition was most strongly associated with difficulties operating gadgets/appliances (OR 3.65, 95%CI: 2.82-4.72), lack of interest and/or initiative (3.52: 2.84-4.36), misplacing or losing objects (3.25: 2.64-4.01), and lack of attention and/or concentration (2.62: 2.12-3.26). CONCLUSIONS: Verbal repetition is a common symptom in people at all stages of dementia but is most commonly targeted for monitoring and treatment effects in its mild stage. Much research is required to further elucidate the underlying mechanisms and the effect of different treatment strategies.

The New Criteria for Alzheimer's Disease - Implications for Geriatricians.

Two new sets of criteria for Alzheimer's disease (AD) are now in play, including one set released in 2014, and a proposal for a "new lexicon" for how to describe the disease spectrum. A 2012 Canadian consensus conference said that to then, none of the new criteria or terminology would change primary care practice; that is still likely to be so. For dementia consultants, however, the new criteria pose challenges and offer opportunities. In general, the new criteria see an expanded role for bio-markers. Even so, the evidence base for this remains incomplete. Our understanding of the neuropathological criteria for dementia changed as the evidence base included more community cases. This is likely to inform the experience with biomarkers. At present, each of the criteria specifies an exclusive research role. Still, wider uptake is likely, especially in the United States. Geriatricians should be aware of the fundamental change in the terminology now being employed: AD diagnosis no longer obliges a diagnosis of dementia. Until more data emerge-something to which geriatricians can contribute-there is reason to be cautious in the adoption of the new criteria, as they are likely to be least applicable to older adults.

Risk score, causes, and clinical impact of failure of transradial approach for percutaneous coronary interventions.

OBJECTIVES: To study the causes of and to develop a risk score for failure of transradial approach (TRA) for percutaneous coronary intervention (PCI). BACKGROUND: TRA-PCI failure has been reported in 5% to 10% of cases. METHODS: TRA-PCI failure was categorized as primary (clinical reasons) or crossover failure. Multivariate analysis was performed to determine independent predictors of TRA-PCI failure, and an integer risk score was developed. RESULTS: From January to June 2010, TRA-PCI was attempted in 1,609 (97.3%) consecutive patients, whereas 45 (2.7%) had primary TRA-PCI failure. Crossover TRA-PCI failure occurred in 30 (1.8%) patients. Causes of primary TRA-PCI failure included chronic radial artery occlusion (11%), previous coronary artery bypass graft (27%), and cardiogenic shock (20%). Causes for crossover TRA-PCI failure included: inadequate puncture in 17 patients (57%); radial artery spasm in 5 (17%); radial loop in 4 (13%); subclavian tortuosity in 2 (7%); and inadequate guide catheter support in 2 (7%) patients. Female sex (odds ratio [OR]: 3.2; 95% confidence interval [CI]: 1.95 to 5.26, p < 0.0001), previous coronary artery bypass graft (OR: 6.1; 95% CI: 3.63 to 10.05, p < 0.0001), and cardiogenic shock (OR: 11.2; 95% CI: 2.78 to 41.2, p = 0.0011) were independent predictors of TRA-PCI failure. Risk score values from 0 to 7 predicted a TRA-PCI failure rate from 2% to 80%. CONCLUSIONS: In a high-volume radial center, 2.7% of patients undergoing PCI are excluded from initial TRA on clinical grounds, whereas crossover to femoral approach is required in only 1.8% of the cases. A new simple clinical risk score is developed to predict TRA-PCI failure.

Successive transradial access for coronary procedures: experience of Quebec Heart-Lung Institute.

BACKGROUND: Transradial approach (TRA) for cardiac catheterizations and interventions improves clinical outcomes compared with transfemoral access, and its use is increasing worldwide. However, there are limited data on successive use of same artery for repeat procedures. METHODS: Between May 2010 and May 2011, all consecutive patients undergoing a repeat TRA procedure (≥2) were retrospectively identified. Success rates and reasons for failure to use ipsilateral radial artery for repeat access were identified. RESULTS: A total of 519 patients underwent 1,420 procedures. In 480 patients (92%), right radial artery was used as initial access, and left radial artery, in 39 patients. All patients underwent ≥2 procedures; 218 patients, ≥3; 87 patients, ≥4; 39 patients, ≥5; 19 patients, ≥6; 11 patients, ≥7; and 5 patients, ≥8 procedures. Two patients had, respectively, 9 and 10 procedures. The success rate for second attempt was 93%, 81% for third, and declining to 60% for ≥8. Linear regression analysis estimated a 5% failure rate for each repeat attempt (R(2) = 0.87, P = .007). The main reason for failure was related to clinical radial artery occlusion (RAO) including absent or faint pulse, poor oximetry, and failed puncture. All patients with clinical RAO were asymptomatic. By multivariate analysis, female gender (odds ratio [OR] 3.08, 95% CI 1.78-5.39, P < .0001), prior coronary artery bypass graft (OR 5.26, 95% CI 2.67-10.42, P < .0001), and repeat radial access (OR 2.14, 95% CI 1.70-2.76, P < .0001) were independent predictors of radial access failure. CONCLUSION: Successive TRA is both feasible and safe in most cases for up to 10 procedures. However, failure rate for TRA increases with successive procedures, primarily due to clinical RAO. Strategies to minimize the risks of chronic clinical RAO and allow repeat use of ipsilateral radial artery need to be further defined.