Pierre-Hugues Carmichael

Omega-3 fatty acids and risk of dementia: the Canadian Study of Health and Aging

BACKGROUND Omega-3 polyunsaturated fatty acids (n-3 PUFAs) may protect against dementia, although epidemiologic studies have yielded inconclusive results. Fish is the main dietary source of n-3 PUFAs and is sometimes contaminated with mercury. This neurotoxicant may modify the association with dementia. OBJECTIVE We evaluated the association of erythrocyte membrane total n-3 PUFAs, docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and blood mercury with the incidence of dementia and Alzheimer disease (AD) in the Canadian Study of Health and Aging (CSHA) with adjustment for confounders including apolipoprotein E epsilon4 (APOE epsilon4) status. DESIGN The CSHA is a cohort study of a representative sample of persons aged > or =65 y, conducted from 1991 to 2002. A subsample of 663 nondemented CSHA subjects with a complete clinical examination, blood samples, and follow-up information was eligible for prospective analyses on laboratory measurements. Of these, 149 were incident cases of dementia, including 105 with AD. RESULTS In adjusted Cox regression models with age as the time scale, there were no associations between total n-3 PUFAs, DHA, or EPA and dementia or AD. In contrast, a mercury concentration in the highest quartile was associated with a reduced risk of dementia (hazard ratio: 0.53; 95% CI: 0.33, 0.88). However, significant risk reductions were limited to subjects with concentrations of both n-3 PUFAs and mercury that were above the median. There was no modification of risk by APOE epsilon4 status. CONCLUSIONS No associations between n-3 PUFAs and dementia or AD were found. The results regarding mercury may indicate a spurious association.

Detecting Delirium and Subsyndromal Delirium Using Different Diagnostic Criteria among Demented Long-Term Care Residents

OBJECTIVES To evaluate the impact of using different diagnostic criteria on prevalence rates of delirium and subsyndromal delirium (SSD) among demented long-term care (LTC) residents. DESIGN Descriptive study. SETTING LTC settings in Quebec City, Canada. PARTICIPANTS Participants were 155 individuals aged 65 and older, with dementia. MEASUREMENTS (1) Prevalence rates of delirium according to: (a) the Diagnostic and Statistical Manual of Mental Disorders (DSM-III, DSM-III-R, and DSM-IV) and (b) the Confusion Assessment Method (CAM) algorithms for definite and probable delirium; and (2) prevalence rates of SSD employing 2 definitions described in previous studies. RESULTS Prevalence rates of delirium according to each set of criteria were 26.5% for DSM-III; 29% for DSM-IV-TR; 41.3% for DSM-III-R; 45.8% for CAM algorithm for definite delirium; and 70.3% for CAM algorithm for probable delirium. A total of 109 subjects (70.3%) were identified as delirious consistent with at least one classification and 37 (23.9%) met all the sets of criteria considered. Prevalence rates for SSD were 75 (48.4%) and 78 (50.3%) depending on the definition employed. CONCLUSION Prevalence rates for delirium are much affected by the diagnostic formulations used. The use of DSM-IV-TR among this population could result in fewer cases being identified as delirious and thus compromise proper care for those individuals. Considering that SSD was prevalent among this population, a systematic implementation of protocols targeting risk factors of delirium might be beneficial among demented LTC residents.

Nonsteroidal anti-inflammatory drug use and the risk of cognitive impairment and Alzheimer's disease.

Some observational studies have established an association between exposure to nonsteroidal anti‐inflammatory drugs (NSAIDs) and a decreased risk of subsequently developing Alzheimers disease (AD). Mild cognitive impairment or cognitive impairment, not dementia (CIND) is more likely to convert to AD, and no specific preventive method is currently available. The objective of this study was to determine the association of NSAID use in 5276 cognitively normal subjects of the Canadian Study of Health and Aging, a 10‐year population‐based cohort study, with the incidence of CIND, AD, and all‐cause dementia.

Predisposing Factors Associated With Delirium Among Demented Long-Term Care Residents

This was a cross-sectional study to investigate predisposing factors associated with delirium among demented long-term-care residents and to assess the cumulative effect of these factors on the likelihood of having delirium. Of the 155 participants, 109 (70.3%) were found delirious according to the confusion assessment method. Among these individuals, age (OR = 1.07; 95% CI = 1.05-1.10) and severity of dementia (OR = 1.05; 95% CI = 1.03-1.07) were the most associated factors of delirium. The likelihood of being in delirium increased with the number of associated predisposing factors present (OR = 1.67; 95% CI = 1.11-2.51). Associated factors identified were level of functional autonomy, pain, depression, behavioral disturbances, number of medications, dehydration, fever, and malnutrition. Identification of predisposing factors will help nurses in detecting those residents in long-term care settings who are at high-risk for delirium, as well as in designing preventive intervention strategies for delirium, based on these factors.

Detection of delirium by nurses among long-term care residents with dementia

BackgroundDelirium is a prevalent problem in long-term care (LTC) facilities where advanced age and cognitive impairment represent two important risk factors for this condition. Delirium is associated with numerous negative outcomes including increased morbidity and mortality. Despite its clinical importance, delirium often goes unrecognized by nurses. Although rates of nurse-detected delirium have been studied among hospitalized older patients, this issue has been largely neglected among demented older residents in LTC settings. The goals of this study were to determine detection rates of delirium and delirium symptoms by nurses among elderly residents with dementia and to identify factors associated with undetected cases of delirium.MethodsIn this prospective study (N = 156), nurse ratings of delirium were compared to researcher ratings of delirium. This procedure was repeated for 6 delirium symptoms. Sensitivity, specificity, positive and negative predictive values were computed. Logistic regressions were conducted to identify factors associated with delirium that is undetected by nurses.ResultsDespite a high prevalence of delirium in this cohort (71.5%), nurses were able to detect the delirium in only a minority of cases (13%). Of the 134 residents not identified by nurses as having delirium, only 29.9% of them were correctly classified. Detection rates for the 6 delirium symptoms varied between 39.1% and 58.1%, indicating an overall under-recognition of symptoms of delirium. Only the age of the residents (≥ 85 yrs) was associated with undetected delirium (OR: 4.1; 90% CI: [1.5–11.0]).ConclusionDetection of delirium is a major issue for nurses that clearly needs to be addressed. Strategies to improve recognition of delirium could result in a reduction of adverse outcomes for this very vulnerable population.

Relationship between delirium and behavioral symptoms of dementia.

BACKGROUND Persons with dementia frequently present behavioral and psychological symptoms as well as delirium. However, the association between these has received little attention from researchers and current knowledge in this area is limited. The purpose of this study was to examine the relation between delirium and behavioral symptoms of dementia (BSD). METHODS Participants were 155 persons with a diagnosis of dementia, 109 (70.3%) of whom were found delirious according to the Confusion Assessment Method. BSD were assessed using the Nursing Home Behavior Problem Scale. RESULTS Participants with delirium presented significantly more BSD than participants without delirium. More specifically, they presented more wandering/trying to leave, sleep problems, and irrational behavior after controlling for cognitive problems and use of antipsychotics and benzodiazepines. Most relationships between participant characteristics and BSD did not differ according to the presence or absence of delirium, but some variables, notably sleep problems, were more strongly associated to BSD in persons with delirium. CONCLUSIONS Although correlates of BSD in persons with delirium superimposed on dementia are generally similar to those in persons with dementia alone, delirium is associated with a higher level of BSD. Results of this study have practical implications for the detection of delirium superimposed on dementia, the management of behavioral disturbances in patients with delirium, and caregiver burden.

Factors associated with delirium severity among older persons with dementia.

ABSTRACT Delirium is a common cause of functional and cognitive decline, morbidity, and mortality among hospitalized elderly individuals. Several studies reveal that the prognosis of delirium is worse among elderly individuals with severe delirium. In light of these findings, it is important to identify which factors are associated with delirium severity: individual (predisposing) or environmental (precipitating) factors. This study wanted to investigate individual and environmental factors associated with delirium severity among older persons with delirium superimposed on dementia. This study is a secondary analysis of a cross-sectional study (N = 71) on delirium carried out in three long-term care facilities and one long-term care unit of a large regional hospital. Of the 29 potential risk factors considered, researchers found 6 to be significantly associated with delirium severity in univariate analysis: marital status (being married), severity of dementia, lower functional autonomy, less medication consumption, presence of behavioral problems, and inadequacy of the physical environment. In multivariate analysis, only marital status (being married) and severity of dementia remained statistically associated with delirium severity. Results of this study provide further evidence that the weakened brain functions of persons with dementia increases not only the risk of delirium but also its severity. Given the poor outcomes associated with delirium severity, nurses need to pay closer attention to the predisposing and precipitating factors of delirium severity.

Recognizing acute delirium as part of your routine (RADAR): a validation study

BackgroundAlthough detection of delirium using the current tools is excellent in research settings, in routine clinical practice, this is not the case. Together with nursing staff, we developed a screening tool (RADAR) to address certain limitations of existing tools, notably administration time, ease-of-use and generalizability. The purpose of this study was not only to evaluate the validity and reliability of RADAR but also to gauge its acceptability among the nursing staff in two different clinical settings.MethodsThis was a validation study conducted on three units of an acute care hospital (medical, cardiology and coronary care) and five units of a long-term care facility. A total of 142 patients and 51 residents aged 65 and over, with or without dementia, participated in the study and 139 nurses were recruited and trained to use the RADAR tool. Data on each patient/resident was collected over a 12-hour period. The nursing staff and researchers administered RADAR during the scheduled distribution of medication. Researchers used the Confusion Assessment Method to determine the presence of delirium symptoms. Delirium itself was defined as meeting the criteria for DMS-IV-TR delirium. Inter-rater reliability, convergent, and concurrent validity of RADAR were assessed. At study end, 103 (74%) members of the nursing staff completed the RADAR feasibility and acceptability questionnaire.ResultsPercentages of agreement between RADAR items that bedside nurses administered and those research assistants administered varied from 82% to 98%. When compared with DSM-IV-TR criterion-defined delirium, RADAR had a sensitivity of 73% and a specificity of 67%. Participating nursing staff took about seven seconds on average, to complete the tool and it was very well received (≥98%) overall.ConclusionsThe RADAR tool proved to be efficient, reliable, sensitive and very well accepted by nursing staff. Consequently, it becomes an appropriate new option for delirium screening among older adults, with or without cognitive impairment, in both hospitals and nursing homes. Further projects are currently underway to validate the RADAR among middle-aged adults, as well as in newer clinical settings; home care, emergency department, medical intensive care unit, and palliative care.

Adverse Drug Reactions Reported With Cholinesterase Inhibitors An Analysis of 16 Years of Individual Case Safety Reports From VigiBase

Background: No worldwide pharmacovigilance study evaluating the spectrum of adverse drug reactions (ADRs) induced by cholinesterase inhibitors (ChEI) in Alzheimer’s disease has been conducted since their emergence on the market. Objective: To describe ChEI related ADRs in Alzheimer’s disease (donepezil, rivastigmine, and galantamine) and characterize their seriousness as reported by national pharmacovigilance systems to VigiBase, a World Health Organization International Drug Monitoring Program database, between 1998 and 2013. Methods: All ChEI related reports, submitted to VigiBase between 1998 and 2013 from the five continents were extracted. Analyses were carried out for general, serious, and nonserious ADRs. Results: A total of 18 955 reports (43 753 ADRs) from 58 countries were reported: 60.1% in women; mean age 77.4 ± 9.1 years. Most reports originated from Europe (47.6%) and North America (40.4%). Rivastigmine and donepezil were involved in most reports (41.4% each). The most frequently reported ADRs were neuropsychiatric (31.4%), gastrointestinal (15.9%), general (11.9%), and cardiovascular (11.7%) disorders. During the 2006-2013 period, serious ADRs remained more often reported than nonserious ones; the most serious were neuropsychiatric (34.0%), general (14.0%), cardiovascular (12.1%), and gastrointestinal (11.6%) disorders. Medication errors were reported in 2.0% of serious cases. Death occurred in 2.3% of the reports. Conclusions: This international pharmacovigilance study highlights the ADR pattern induced by ChEIs. Neuropsychiatric events were the most frequently reported ADRs. Serious cardiovascular events were frequently reported, suggesting that their significance has probably been previously underestimated. Given the frailty of the patients and the frequent comedications, caution is advised before introducing a ChEI.

Evidence summaries (decision boxes) to prepare clinicians for shared decision-making with patients: a mixed methods implementation study

BackgroundDecision boxes (Dboxes) provide clinicians with research evidence about management options for medical questions that have no single best answer. Dboxes fulfil a need for rapid clinical training tools to prepare clinicians for clinician-patient communication and shared decision-making. We studied the barriers and facilitators to using the Dbox information in clinical practice.MethodsWe used a mixed methods study with sequential explanatory design. We recruited family physicians, residents, and nurses from six primary health-care clinics. Participants received eight Dboxes covering various questions by email (one per week). For each Dbox, they completed a web questionnaire to rate clinical relevance and cognitive impact and to assess the determinants of their intention to use what they learned from the Dbox to explain to their patients the advantages and disadvantages of the options, based on the theory of planned behaviour (TPB). Following the 8-week delivery period, we conducted focus groups with clinicians and interviews with clinic administrators to explore contextual factors influencing the use of the Dbox information.ResultsOne hundred clinicians completed the web surveys. In 54% of the 496 questionnaires completed, they reported that their practice would be improved after having read the Dboxes, and in 40%, they stated that they would use this information for their patients. Of those who would use the information for their patients, 89% expected it would benefit their patients, especially in that it would allow the patient to make a decision more in keeping with his/her personal circumstances, values, and preferences. They intended to use the Dboxes in practice (mean 5.6 ± 1.2, scale 1–7, with 7 being “high”), and their intention was significantly related to social norm, perceived behavioural control, and attitude according to the TPB (P < 0.0001). In focus groups, clinicians mentioned that co-interventions such as patient decision aids and training in shared decision-making would facilitate the use of the Dbox information. Some participants would have liked a clear “bottom line” statement for each Dbox and access to printed Dboxes in consultation rooms.ConclusionsDboxes are valued by clinicians. Tailoring of Dboxes to their needs would facilitate their implementation in practice.