Perspectives on the diagnosis and management of functional cognitive disorder: An international Delphi study

BACKGROUND

Current proposed criteria for functional cognitive disorder (FCD) have not been externally validated. We sought to analyse the current perspectives of cognitive specialists in the diagnosis and management of FCD in comparison with neurodegenerative conditions.

METHODS

International experts in cognitive disorders were invited to assess seven illustrative clinical vignettes containing history and bedside characteristics alone. Participants assigned a probable diagnosis and selected the appropriate investigation and treatment. Qualitative, quantitative and inter-rater agreement analyses were undertaken.

RESULTS

Eighteen diagnostic terminologies were assigned by 45 cognitive experts from 12 countries with a median of 13 years of experience, across the seven scenarios. Accurate discrimination between FCD and neurodegeneration was observed, independently of background and years of experience: 100% of the neurodegenerative vignettes were correctly classified and 75%-88% of the FCD diagnoses were attributed to non-neurodegenerative causes. There was <50% agreement in the terminology used for FCD, in comparison with 87%-92% agreement for neurodegenerative syndromes. Blood tests and neuropsychological evaluation were the leading diagnostic modalities for FCD. Diagnostic communication, psychotherapy and psychiatry referral were the main suggested management strategies in FCD.

CONCLUSIONS

Our study demonstrates the feasibility of distinguishing between FCD and neurodegeneration based on relevant patient characteristics and history details. These characteristics need further validation and operationalisation. Heterogeneous labelling and framing pose clinical and research challenges reflecting a lack of agreement in the field. Careful consideration of FCD diagnosis is advised, particularly in the presence of comorbidities. This study informs future research on diagnostic tools and evidence-based interventions.

Association of Incident Stroke Risk With an IL-18-Centered Inflammatory Network Biomarker Composite

BACKGROUND

A coordinated network of circulating inflammatory molecules centered on the pleotropic pro-atherogenic cytokine interleukin-18 (IL-18) is linked to cerebral small vessel disease. We sought to validate the association of this inflammatory biomarker network with incident stroke risk, cognitive impairment, and imaging metrics in a sample of the Framingham Offspring Cohort.

METHODS

Using available baseline measurements of serum levels of IL-18, GDF (growth and differentiation factor)-15, soluble form of receptor for advanced glycation end products, myeloperoxidase, and MCP-1 (monocyte chemoattractant protein-1) from Exam 7 of the Framingham Offspring Cohort (1998-2001), we constructed a population-normalized, equally weighted log-transformed mean Z-score value representing the average level of each serum analyte to create an inflammatory composite score (ICS5). Multivariable regression models were used to determine the association of ICS5 with incident stroke, brain magnetic resonance imaging features, and cognitive testing performance.

RESULTS

We found a significant association between ICS5 score and increased risk for incident all-cause stroke (hazard ratio, 1.48 [95% CI, 1.05-2.08]; P=0.024) and ischemic stroke (hazard ratio, 1.51 [95% CI, 1.03-2.21]; P=0.033) in the Exam 7 cohort of 2201 subjects (mean age 62±9 years; 54% female) aged 45+ years with an all-cause incident stroke rate of 6.1% (135/2201) and ischemic stroke rate of 4.9% (108/2201). ICS5 and its component serum markers are all associated with the Framingham Stroke Risk Profile score (β±SE, 0.19±0.02; P<0.0001). In addition, we found a significant inverse association of ICS5 with a global cognitive score, derived from a principal components analysis of the neuropsychological battery used in the Framingham cohort (-0.08±0.03; P=0.019). No association of ICS5 with magnetic resonance imaging metrics of cerebral small vessel disease was observed.

CONCLUSIONS

Circulating serum levels of inflammatory biomarkers centered on IL-18 are associated with an increased risk of stroke and cognitive impairment in the Framingham Offspring Cohort. Linking specific inflammatory pathways to cerebral small vessel disease may enhance individualized quantitative risk assessment for future stroke and vascular cognitive impairment.

Population attributable fraction of hypertension for dementia: global, regional, and national estimates for 186 countries

Background

Quantifying the proportion of dementia attributable to highly prevalent modifiable risk factors, such as hypertension, is important in informing effective dementia prevention strategies. We aim to quantify the population attributable fraction (PAF) of hypertension for dementia (the proportion of dementia cases that would not occur if hypertension was eliminated) at global, regional, and national levels.

Methods

In this study, we searched international and governmental websites for global, regional, and national data reporting population hypertension (according to 10-year age categories) and dementia prevalence. MEDLINE was searched for studies reporting the risk of dementia from age at hypertension diagnosis from database inception to December 31, 2022. Longitudinal observational studies with >500 participants reporting hazard ratios by age at hypertension diagnosis for risk of future all-cause dementia were eligible for inclusion. Studies excluded had cross-sectional methodology, specific vascular dementia or 'cognitive impairment' outcomes, and no age-specific metrics of association reported. The PAF of hypertension for dementia was calculated globally and for each country and region worldwide.

Findings

Data from the Global Burden of Disease, United Nations Population Prospectus, NCD Risk Factor Collaboration, UK Biobank, and Atherosclerosis Risk in Communities Study were obtained. 186 countries reported dementia and hypertension prevalence data. The global PAF of hypertension for dementia was 15.8% [95% Credible Interval (CI), 8.8%-22.7%]. Latin America and the Caribbean (18.0% [95% CI, 9.4%-26.6%]), and Europe (17.2% [95% CI, 9.6%-24.7%]) had the highest PAF of hypertension for dementia. Hypertension diagnosed between the ages of 30-44 had the highest age-specific global attributable fraction for dementia (8.4% [95% CI, 3.4%-13.5%]), followed by ages 45-54 (2.92% [ 95% CI, 0.96%-4.88%]), 55-64 (2.59% [95% CI, 1.15%-4.03%]) and 65-74 (1.82% [95% CI, -2.31%-5.96%]).

Interpretation

The population attributable risk of hypertension for dementia is 15.8%, suggesting that optimal detection and treatment, particularly at midlife, has the potential to markedly reduce the global burden of dementia.

Funding

Wellcome Trust; Health Research Board of Ireland; Alzheimer's Association.

Clinical Reasoning: A 25-Year-Old Woman With Eye Swelling and Headache

Cerebral venous sinus thrombosis (CVST) is uncommon. Risk factors include inherited and acquired factors. Rapid diagnosis and treatment is essential and can help prevent complications, which can include seizures and visual disturbance. A 25-year-old woman with a background history of CVST and intermittent warfarin use presented to the hospital in 2021 with a 3-month history of progressive eye swelling and headache. Her headache was located in the right frontal region and worsened with movement. Her workup was consistent with recurrent CVST and dural arteriovenous fistula. IR-guided embolization of the fistulas and stenting of her sinuses was performed. She was treated with dual antiplatelet therapy and therapeutic tinzaparin. Her symptoms improved markedly over several days, with improvement in headache and visual acuity. This case illustrates the potential for severe complications including visual disturbance in untreated CVST, as well as the importance of a thorough history and examination in aiding the recognition of the condition.

Proteome Network Analysis Identifies Potential Biomarkers for Brain Aging

BACKGROUND

Alzheimer's disease and related dementias (ADRD) involve biological processes that begin years to decades before onset of clinical symptoms. The plasma proteome can offer insight into brain aging and risk of incident dementia among cognitively healthy adults.

OBJECTIVE

To identify biomarkers and biological pathways associated with neuroimaging measures and incident dementia in two large community-based cohorts by applying a correlation-based network analysis to the plasma proteome.

METHODS

Weighted co-expression network analysis of 1,305 plasma proteins identified four modules of co-expressed proteins, which were related to MRI brain volumes and risk of incident dementia over a median 20-year follow-up in Framingham Heart Study (FHS) Offspring cohort participants (n = 1,861). Analyses were replicated in the Cardiovascular Health Study (CHS) (n = 2,117, mean 6-year follow-up).

RESULTS

Two proteomic modules, one related to protein clearance and synaptic maintenance (M2) and a second to inflammation (M4), were associated with total brain volume in FHS (M2: p = 0.014; M4: p = 4.2×10-5). These modules were not significantly associated with hippocampal volume, white matter hyperintensities, or incident all-cause or AD dementia. Associations with TCBV did not replicate in CHS, an older cohort with a greater burden of comorbidities.

CONCLUSIONS

Proteome networks implicate an early role for biological pathways involving inflammation and synaptic function in preclinical brain atrophy, with implications for clinical dementia.

Determining Vascular Risk Factors for Dementia and Dementia Risk Prediction Across Mid- to Later Life: The Framingham Heart Study

BACKGROUND AND OBJECTIVES

The association between vascular risk factors and dementia varies with age, making generalizability of dementia risk prediction rules to individuals of different ages challenging. We determined the most important vascular risk factors for inclusion in age-specific dementia risk scores.

METHODS

Framingham Heart Study Original and Offspring cohort participants with available data on the Framingham Stroke Risk Profile (FSRP) at midlife (age 55; n = 4,899, 57% women), late life (ages 65 or 70), or later life (ages 75 or 80 [n = 2,386, 62% women]) were followed for 10-year incident dementia risk from ages 65, 70, 75, and 80.

RESULTS

Age- and sex-adjusted midlife risk factors associated with 10-year risk of dementia from age 65 included FSRP (hazard ratio [HR] 1.16, 95% CI 1.06-1.26, per 1 SD increment in log-transformed score), diabetes mellitus (DM; HR 4.31, 95% CI 1.97-9.43), and systolic blood pressure (SBP; HR 1.12, 95% CI 1.02-1.24, per 10 mm Hg increment). Late-life risk factors associated with 10-year incident dementia from ages 65 or 70 included FSRP (age 65 only: HR 1.06, 95% CI 1.02-1.10), antihypertensive use (age 65 reported: HR 1.66, 95% CI 1.12-2.46), DM (age 65 reported: HR 1.96, 95% CI 1.09-3.52), atrial fibrillation (age 65 reported: HR 2.30, 95% CI 1.00-5.27), nonstroke cardiovascular disease (nsCVD; age 65 reported: HR 1.95, 95% CI 1.24-3.07), and stroke (age 70 only: HR 3.61, 95% CI 2.21-5.92). Later-life risk factors associated with 10-year incident dementia from ages 75 or 80 included antihypertensive use (age 80 only: HR 0.74, 95% CI 0.62-0.89), DM (age 80 reported: HR 1.40, 95% CI 1.04-1.89), atrial fibrillation (age 80 reported: HR 1.43, 95% CI 1.07-1.92), and stroke (age 80 reported: HR 1.63, 95% CI 1.13-2.35). In stepwise models, SBP and DM at age 55, nsCVD at age 65, DM and stroke at ages 70 and 75, and DM, stroke, and use of antihypertensives (protective) at age 80 were the most important vascular risk factors for dementia.

DISCUSSION

Our findings support the use of age-specific dementia risk scores, which should prioritize including, at age 55, SBP and DM; at age 65, nsCVD; at ages 70 and 75, DM and stroke; and at age 80, DM, stroke, and antihypertensive use.

Menopause Status Moderates Sex Differences in Tau Burden: A Framingham PET Study

OBJECTIVE

Women have a higher lifetime risk of Alzheimer's disease (AD) than men. Among cognitively normal (CN) older adults, women exhibit elevated tau positron emission tomography (PET) signal compared with men. We explored whether menopause exacerbates sex differences in tau deposition in middle-aged adults.

METHODS

328 CN participants from the Framingham Study (mean age = 57 years (±10 years), 161 women, of whom, 104 were post-menopausal) underwent tau and β-amyloid (Aβ)-PET neuroimaging. We examined global Aβ-PET, and tau-PET signal in 5 regions identified a priori as demonstrating significant sex differences in older adults (in temporal, inferior parietal, middle frontal, and lateral occipital regions). We examined sex and menopause status-related differences in each region-of-interest, using linear regressions, as well as interactions with Aβ and APOEε4 genotype.

RESULTS

Women exhibited higher tau-PET signal (p < 0.002), and global Aβ-PET (p = 0.010), than men in inferior parietal, rostral middle frontal, and lateral occipital regions. Compared with age-matched men, post-menopausal women showed significantly higher tau-PET signal in parieto-occipital regions (p < 0.0001). By contrast, no differences in tau-PET signal existed between pre-menopausal women and men. Aβ-PET was not associated with menopausal status or age. Neither Aβ-PET nor APOEε4 status moderated sex or menopause associations with tau-PET.

INTERPRETATION

Clear divergence in tauopathy between the sexes are apparent approximately 20 years earlier than previously reported. Menopause status moderated sex differences in Aβ and tau-PET burden, with tau first appearing post-menopause. Sex and menopause differences consistently appeared in middle frontal and parieto-occipital regions but were not moderated by Aβ burden or APOEε4, suggesting that menopause-related tau vulnerability may be independent of AD-related pathways. ANN NEUROL 2022;92:11-22.

Identifying Blood Biomarkers for Dementia Using Machine Learning Methods in the Framingham Heart Study

Blood biomarkers for dementia have the potential to identify preclinical disease and improve participant selection for clinical trials. Machine learning is an efficient analytical strategy to simultaneously identify multiple candidate biomarkers for dementia. We aimed to identify important candidate blood biomarkers for dementia using three machine learning models. We included 1642 (mean 69 ± 6 yr, 53% women) dementia-free Framingham Offspring Cohort participants attending examination, 7 who had available blood biomarker data. We developed three machine learning models, support vector machine (SVM), eXtreme gradient boosting of decision trees (XGB), and artificial neural network (ANN), to identify candidate biomarkers for incident dementia. Over a mean 12 ± 5 yr follow-up, 243 (14.8%) participants developed dementia. In multivariable models including all 38 available biomarkers, the XGB model demonstrated the strongest predictive accuracy for incident dementia (AUC 0.74 ± 0.01), followed by ANN (AUC 0.72 ± 0.01), and SVM (AUC 0.69 ± 0.01). Stepwise feature elimination by random sampling identified a subset of the nine most highly informative biomarkers. Machine learning models confined to these nine biomarkers showed improved model predictive accuracy for dementia (XGB, AUC 0.76 ± 0.01; ANN, AUC 0.75 ± 0.004; SVM, AUC 0.73 ± 0.01). A parsimonious panel of nine candidate biomarkers were identified which showed moderately good predictive accuracy for incident dementia, although our results require external validation.

Blood Phosphorylated Tau 181 as a Biomarker for Amyloid Burden on Brain PET in Cognitively Healthy Adults

BACKGROUND

Plasma phosphorylated-tau181 (p-tau181) is a promising biomarker for Alzheimer's disease (AD) and may offer utility for predicting preclinical disease.

OBJECTIVE

To evaluate the prospective association between plasma p-tau181 and amyloid-β (Aβ) and tau-PET deposition in cognitively unimpaired individuals.

METHODS

Plasma p-tau181 levels were measured at baseline in 52 [48% women, mean 64.4 (SD 5.5) years] cognitively unimpaired Framingham Offspring cohort participants using samples stored between 2011-2014 who subsequently underwent 11C-Pittsburgh Compound-B (PiB)-PET and/or 18F-Flortaucipir (FTP)-PET scans (n = 18 with tau-PET) a mean of 6.8 (SD 0.6) years later. Our primary outcomes included Aβ-precuneus, Aβ-FLR (frontal, lateral, and retrosplenial cortices) and tau-global composite region PET deposition. Secondary outcomes included individual regional Aβ and tau PET-deposition. P-tau181 was compared with plasma neurofilament light chain (NFL) and glial fibrillary acidic protein (GFAP) in predicting PET outcomes.

RESULTS

P-tau181 was associated with increased Aβ deposition in the FLR (β±SE, 1.25±0.30, p < 0.0001), precuneus (1.35±0.29, p < 0.001), and other cortical regions. Plasma NFL (1.30±0.49, p = 0.01) and GFAP (1.46±0.39, p < 0.001) were also associated with FLR Aβ deposition. In models including all three biomarkers adjusted for age, sex, APOE E4 allele, AD polygenic risk score and cortical atrophy score, p-tau181 (0.93±0.31, p < 0.01, R2 = 0.18) and GFAP (0.93±0.41, p = 0.03, R2 = 0.11), but not NFL (0.25±0.51, p = 0.62, R2 = 0.01), were associated with FLR-Aβ deposition. Plasma p-tau181 was not associated with tau-PET burden.

CONCLUSION

In cognitively unimpaired adults, elevated plasma p-tau181 is associated with future increased Aβ deposition across multiple brain regions. Our results highlight the potential utility of p-tau181 as a blood-biomarker to screen for brain-amyloid deposition in cognitively healthy individuals in a community-setting.

Plasma EFEMP1 Is Associated with Brain Aging and Dementia: The Framingham Heart Study

BACKGROUND

Epidermal growth factor containing fibulin extracellular matrix protein-1 (EFEMP1) has been associated with increased white matter hyperintensities (WMH) burden and disorders of premature aging and may have a shared pathophysiological role in the development of WMH and dementia.

OBJECTIVE

To determine the association between plasma EFEMP1 levels and MRI markers of vascular brain injury and incident all-cause and Alzheimer's disease (AD) dementia.

METHODS

We measured plasma EFEMP1 levels in 1597 [53% women, mean age 68.7 (SD 5.7) years] dementia-free Framingham Offspring cohort participants between 1998-2001 and subsequently followed them for incident dementia. Secondary outcomes included stroke, structural MRI brain measures and neurocognitive test performance.

RESULTS

During a median 11.8 [Q1, Q3 : 7.1, 13.3] year follow-up, 131 participants developed dementia. The highest quintile of plasma EFEMP1, compared to the bottom four quintiles, was associated with an increased risk of time to incident all-cause dementia (HR 1.77, 95% CI 1.18-2.64) and AD dementia (HR 1.76, 95% CI 1.11-2.81) but not with markers of vascular brain injury (WMH, covert brain infarcts or stroke). Higher circulating EFEMP1 concentrations were also cross-sectionally associated with lower total brain (β±SE, -0.28±0.11, p = 0.01) and hippocampal volumes (-0.006±0.003, p = 0.04) and impaired abstract reasoning (Similarities test, -0.18±0.08, p = 0.018 per standard deviation increment in EFEMP1).

CONCLUSION

Elevated circulating EFEMP1 is associated with an increased risk of all-cause and AD dementia, smaller hippocampal and total brain volumes, and poorer cognitive performance. EFEMP1 may play an important biological role in the development of AD dementia. Further studies to validate these findings are warranted.

Interleukin-6 Interacts with Sleep Apnea Severity when Predicting Incident Alzheimer's Disease Dementia

Because of their roles as potential risk factors, we evaluated whether obstructive sleep apnea (OSA) severity interacts with interleukin-6 (IL-6) in predicting incident dementia of the Alzheimer's type (DAT). In 269 dementia-free participants, IL-6 and the apnea-hypopnea index (AHI) were measured at baseline and incident DAT was surveilled for up to 22.8 years. Cox models revealed a significant interaction: In the lowest IL-6 quartile only, a higher AHI was associated with an elevated risk of DAT. The association between OSA severity and incident DAT might be especially apparent in the absence of inflammation or absence of potential benefits from IL-6.

Systemic inflammation as a moderator between sleep and incident dementia

STUDY OBJECTIVES

To determine whether C-reactive protein (CRP), a marker of systemic inflammation, moderates the association between sleep and incident dementia.

METHODS

We studied Framingham Heart Study participants who completed at baseline a serum CRP assessment and in-home polysomnography to measure sleep duration, sleep efficiency, sleep latency, wake after sleep onset (WASO), number of awakenings, arousal index, and apnea-hypopnea index. Participants were divided into groups according to their CRP level: low (<1 mg/L), average (1-3 mg/L), and high inflammation (>3 mg/L). Surveillance for outcomes (incident all-cause and Alzheimer's disease [AD] dementia) commenced at baseline and continued up to 22.5 years.

RESULTS

In 291 participants (mean age 67.5 ± 4.9 years, 51.6% men) followed for 13.4 ± 5.4 years, we observed 43 cases of all-cause dementia, 33 of which were clinically consistent with AD. Whereas no direct association between CRP or sleep exposures was observed with incident dementia, CRP levels interacted with nighttime wakefulness when predicting both incident all-cause and AD dementia. In the high CRP group, longer WASO (hazard ratio [HR], 2.89; 95% CI, 1.31-6.34) and more nighttime awakenings (HR, 4.55; 95% CI, 1.19-17.38) were associated with higher risk of incident dementia. In the low CRP group, fewer nighttime awakenings were associated with a higher risk of incident dementia (HR, 0.07; 95% CI, 0.01-0.68).

CONCLUSIONS

Our findings suggest that inflammation moderates the association between sleep, particularly nighttime wakefulness, and dementia risk. The presence of inflammation may be an important determinant in evaluating how sleep disturbances relate to neurodegeneration.

Growth Differentiation Factor 15 and NT-proBNP as Blood-Based Markers of Vascular Brain Injury and Dementia

Background

GDF15 (growth differentiation factor 15) and NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) may offer promise as biomarkers for cognitive outcomes, including dementia. We determined the association of these biomarkers with cognitive outcomes in a community‐based cohort.

Methods and Results

Plasma GDF15 (n=1603) and NT‐proBNP levels (n=1590) (53% women; mean age, 68.7 years) were measured in dementia‐free Framingham Offspring cohort participants at examination 7 (1998–2001). Participants were followed up for incident dementia. Secondary outcomes included Alzheimer disease dementia, magnetic resonance imaging structural brain measures, and neurocognitive performance. During a median 11.8‐year follow‐up, 131 participants developed dementia. On multivariable Cox proportional‐hazards analysis, higher circulating GDF15 was associated with an increased risk of incident all‐cause and Alzheimer disease dementia (hazard ratio [HR] per SD increment in natural log‐transformed biomarker value, 1.54 [95% CI, 1.22–1.95] and 1.37 [95% CI, 1.03–1.81], respectively), whereas higher plasma NT‐proBNP was also associated with an increased risk of all‐cause dementia (HR, 1.32; 95% CI, 1.05–1.65). Elevated GDF15 was associated with lower total brain and hippocampal volumes, greater white matter hyperintensity volume, and poorer cognitive performance. Elevated NT‐proBNP was associated with greater white matter hyperintensity volume and poorer cognitive performance. Addition of both biomarkers to a conventional risk factor model improved dementia risk classification (net reclassification improvement index, 0.25; 95% CI, 0.05–0.45).

Conclusions

Elevated plasma GDF15 and NT‐proBNP were associated with vascular brain injury on magnetic resonance imaging, poorer neurocognitive performance, and increased risk of incident dementia in individuals aged >60 years. Both biomarkers improved dementia risk classification beyond that of traditional clinical risk factors, indicating their potential value in predicting incident dementia.

0419 IL-6 Moderates the Association Between Obstructive Sleep Apnea Severity and Incident Alzheimer’s Disease: The Framingham Heart Study

Introduction

Both sleep disturbances and inflammation are potential risk factors for Alzheimer’s disease (AD). However, it is unknown how inflammation and sleep interact together to influence the risk of developing AD dementia. Our objective was to evaluate whether interleukin-6 (IL-6) levels interact with sleep disturbances when predicting incident clinical AD.

Methods

We studied participants in the Framingham Heart Study Offspring cohort who completed in-home overnight polysomnography. Sleep characteristics were continuous and included sleep duration, wake after sleep onset (WASO), and apnea-hypopnea index (AHI). Participants were stratified into quartiles of IL-6 levels. Surveillance for incident AD dementia occurred over a mean follow-up of 13.4±5.4 years. Using Cox proportional hazards regression models, we tested the interaction of sleep measures by IL-6 quartiles on incident AD dementia. All analyses adjusted for age and sex and P&lt;0.05 was considered significant.

Results

The final sample included 291 dementia-free participants at baseline (age 67.5±4.9 years, 51.6% men). Approximately one quarter of participants had obstructive sleep apnea (OSA; AHI&gt;15) at baseline (median:6.2, Q1:2,3, Q3:14.3). We observed 33 cases of incident AD dementia during follow-up. Although no interaction was observed for either sleep duration or WASO with IL-6 levels, there was a significant interaction of AHI with IL-6 in predicting AD dementia (p=0.002). In the lowest IL-6 quartile, higher AHI was associated with an elevated risk of AD dementia (hazard ratio, 4.15 [95%CI, 1.42, 12.1], p=0.01) whereas no association between AHI and incident AD was observed in other IL-6 quartiles.

Conclusion

Our findings suggest that the pro-inflammatory cytokine IL-6 moderates the association between OSA and incident AD risk. The association between increasing OSA severity and incident AD was only observed in those with lower IL-6 levels, suggesting that this association might be especially apparent when no other confounding risk factors such as inflammation are present.

Support

The Framingham Heart Study is supported by contracts from the National Heart, Lung and Blood Institute, grants from the National Institute on Aging, and grants from the National Institute of Neurological Disorders and Stroke.

Association of CD14 with incident dementia and markers of brain aging and injury

OBJECTIVE

To test the hypothesis that the inflammatory marker plasma soluble CD14 (sCD14) associates with incident dementia and related endophenotypes in 2 community-based cohorts.

METHODS

Our samples included the prospective community-based Framingham Heart Study (FHS) and Cardiovascular Health Study (CHS) cohorts. Plasma sCD14 was measured at baseline and related to the incidence of dementia, domains of cognitive function, and MRI-defined brain volumes. Follow-up for dementia occurred over a mean of 10 years (SD 4) in the FHS and a mean of 6 years (SD 3) in the CHS.

RESULTS

We studied 1,588 participants from the FHS (mean age 69 ± 6 years, 47% male, 131 incident events) and 3,129 participants from the CHS (mean age 72 ± 5 years, 41% male, 724 incident events) for the risk of incident dementia. Meta-analysis across the 2 cohorts showed that each SD unit increase in sCD14 was associated with a 12% increase in the risk of incident dementia (95% confidence interval 1.03-1.23; p = 0.01) following adjustments for age, sex, APOE ε4 status, and vascular risk factors. Higher levels of sCD14 were associated with various cognitive and MRI markers of accelerated brain aging in both cohorts and with a greater progression of brain atrophy and a decline in executive function in the FHS.

CONCLUSION

sCD14 is an inflammatory marker related to brain atrophy, cognitive decline, and incident dementia.

Circulating ceramide ratios and risk of vascular brain aging and dementia

Background

We determined the association between ratios of plasma ceramide species of differing fatty‐acyl chain lengths and incident dementia and Alzheimer’s disease (AD) dementia in a large, community‐based sample.

Methods

We measured plasma ceramide levels in 1892 [54% women, mean age 70.1 (SD 6.9) yr.] dementia‐free Framingham Offspring Study cohort participants between 2005 and 2008. We related ratios of very long‐chain (C24:0, C22:0) to long‐chain (C16:0) ceramides to subsequent risk of incident dementia and AD dementia. Structural MRI brain measures were included as secondary outcomes.

Results

During a median 6.5 year follow‐up, 81 participants developed dementia, of whom 60 were diagnosed with AD dementia. In multivariable Cox‐proportional hazards analyses, each standard deviation (SD) increment in the ratio of ceramides C24:0/C16:0 was associated with a 27% reduction in the risk of dementia (HR 0.73, 95% CI 0.56–0.96) and AD dementia (HR 0.73, 95% CI 0.53–1.00). The ratio of ceramides C22:0/C16:0 was also inversely associated with incident dementia (HR per SD 0.75, 95% CI 0.57–0.98), and approached statistical significance for AD (HR 0.73, 95% CI 0.53–1.01, P = 0.056). Higher ratios of ceramides C24:0/C16:0 and C22:0/C16:0 were also cross‐sectionally associated with lower white matter hyperintensity burden on MRI (−0.05 ± 0.02, P = 0.02; −0.06 ± 0.02, P = 0.003; respectively per SD increase), but not with other MRI brain measures.

Conclusions

Higher plasma ratios of very long‐chain to long‐chain ceramides are associated with a reduced risk of incident dementia and AD dementia in our community‐based sample. Circulating ceramide ratios may serve as potential biomarkers for predicting dementia risk in cognitively healthy adults.

Circulating IGFBP-2: a novel biomarker for incident dementia

OBJECTIVE

To determine the association between plasma insulin-like growth factor binding protein 2 (IGFBP-2) and cognitive outcomes.

METHODS

We measured plasma IGFBP-2 levels in 1596 (53% women, mean age 68.7 [SD 5.7] years) dementia-free Framingham Offspring cohort participants between 1998 and 2001. Multivariable Cox proportional hazards models related plasma IGFBP-2 to subsequent risk of incident dementia and Alzheimer's disease. MRI brain measures and cognitive performance were included as secondary outcomes.

RESULTS

During a median follow-up of 11.8 (Q1, Q3: 7.1, 13.3) years, 131 participants developed incident dementia, of whom 98 were diagnosed with Alzheimer's disease. The highest tertile of IGFBP-2, compared to the lowest tertile, was associated with an increased risk of incident all-cause dementia (hazard ratio [HR] 2.89, 95% CI 1.63-5.13) and Alzheimer's disease (HR 3.63, 95% CI 1.76-7.50) in multivariable analysis. Higher circulating IGFBP2 levels were also cross-sectionally associated with poorer performance on tests of abstract reasoning but not with MRI-based outcomes. After adding plasma IGFBP-2 levels to a conventional dementia prediction model, 32% of individuals with dementia were correctly assigned a higher predicted risk, while 8% of individuals without dementia were correctly assigned a lower predicted risk (overall net reclassification improvement index, 0.40, 95% CI 0.22-0.59).

INTERPRETATION

Elevated circulating IGFBP-2 levels were associated with an increased risk of both all-cause dementia and Alzheimer's disease. Addition of IGFBP2 plasma levels to a model of traditional risk factors significantly improved dementia risk classification. Manipulation of insulin-like growth factor signaling via IGFBP-2 may be a promising therapeutic target for dementia.

Circulating fibroblast growth factor 23 levels and incident dementia: The Framingham heart study

BACKGROUND

Fibroblast growth factor 23 is an emerging vascular biomarker, recently associated with cerebral small vessel disease and poor cognition in patients on dialysis. It also interacts with klotho, an anti-aging and cognition enhancing protein.

OBJECTIVE

To determine if circulating Fibroblast growth factor 23 (FGF23) is associated with new-onset cognitive outcomes in a community-based cohort of cognitively healthy adults with long-term follow-up.

METHODS

We measured serum FGF23 levels in 1537 [53% women, mean age 68.7 (SD 5.7)] dementia-free Framingham Offspring participants at their 7th quadrennial examination (1998-2001), and followed these participants for the development of clinical all-cause dementia and Alzheimer's disease (AD). Secondary outcomes included MRI-based structural brain measures, and neurocognitive test performance at exam 7.

RESULTS

During a median (Q1, Q3) 12-year (7.0, 13.3) follow up, 122 (7.9%) participants developed dementia, of whom 91 (5.9%) had AD. Proportional-hazards regression analysis, adjusted for age, sex, education, systolic blood pressure, antihypertensive medication, prevalent cardiovascular disease, diabetes mellitus, smoking status and apoE ε4 carrier status, revealed that higher serum FGF23 levels were associated with an increased risk of incident dementia and AD (Hazard ratio [HR] per 1 standard deviation increment in inverse transformed FGF23 level 1.25, 95% CI 1.02-1.53, and 1.32, 95% CI 1.04-1.69, respectively). There was no significant interaction according to presence/absence of significant renal impairment (eGFR <30 versus ≥30ml/min) and risk of dementia (based on 1537; p = 0.97).

CONCLUSIONS

Higher circulating FGF23 is associated with an increased risk of dementia, suggesting that FGF23-related biological pathways may play a role in the development of dementia.

Autoimmune Myopathies: Updates on Evaluation and Treatment

The major forms of autoimmune myopathies include dermatomyositis (DM), polymyositis (PM), myositis associated with antisynthetase syndrome (ASS), immune-mediated necrotizing myopathy (IMNM), and inclusion body myositis (IBM). While each of these conditions has unique clinical and histopathological features, they all share an immune-mediated component. These conditions can occur in isolation or can be associated with systemic malignancies or connective tissue disorders (overlap syndromes). As more has been learned about these conditions, it has become clear that traditional classification schemes do not adequately group patients according to shared clinical features and prognosis. Newer classifications are now utilizing myositis-specific autoantibodies which correlate with clinical and histopathological phenotypes and risk of malignancy, and help in offering prognostic information with regard to treatment response. Based on observational data and expert opinion, corticosteroids are considered first-line therapy for DM, PM, ASS, and IMNM, although intravenous immunoglobulin (IVIG) is increasingly being used as initial therapy in IMNM related to statin use. Second-line agents are often required, but further prospective investigation is required regarding the optimal choice and timing of these agents.

Blood pressure from mid- to late life and risk of incident dementia

OBJECTIVE

To determine the association between blood pressure during midlife (40-64 years) to late life (≥65 years) and risk of incident dementia.

METHODS

This study included 1,440 (758 women, mean age 69 ± 6 years) Framingham Offspring participants who were free of dementia and attended 5 consecutive examinations at 4-year intervals starting at midlife (1983-1987, mean age 55 years) until late life (1998-2001, mean 69 years) and subsequently were followed up for incident dementia (mean 8 years). We determined the effect of midlife hypertension (≥140/90 mm Hg), late life hypertension, lower late life blood pressure (<100/70 mm Hg), persistence of hypertension during mid- to late life, and steep decline in blood pressure from mid- to late life over an 18-year exposure period.

RESULTS

During the follow-up period, 107 participants (71 women) developed dementia. Using multivariable Cox proportional hazards models, we found that midlife systolic hypertension (hazard ratio [HR] 1.57, 95% confidence interval [CI] 1.05-2.35) and persistence of systolic hypertension into late life (HR 1.96, 95% CI 1.25-3.09) were associated with an elevated risk of incident dementia. However, in individuals with low to normal blood pressure (≤140/90 mm Hg) at midlife, a steep decline in systolic blood pressure during mid- to late life was also associated with a >2-fold increase in dementia risk (HR 2.40, 95% CI 1.39-4.15).

CONCLUSIONS

Elevated blood pressure during midlife, persistence of elevated blood pressure into late life, and, among nonhypertensives, a steep decline in blood pressure during mid- to late life were associated with an increased dementia risk in a community-based cohort. Our data highlight the potential sustained cognitive benefits of lower blood pressures in midlife but also suggest that declining blood pressure in older adults with prehypertension or normotension, but not in those with hypertension, may be a risk marker for dementia.

Sleep to Lower Elevated Blood Pressure: A Randomized Controlled Trial (SLEPT)

BACKGROUND

Impaired sleep quality is common and associated with an increased risk of cardiovascular disease (CVD), thought to be mediated through adverse effects on established vascular risk factors, particularly hypertension. We determined if a web-delivered sleep intervention (sleep-hygiene education, stimulus control, and cognitive behavioral therapy) reduces blood pressure compared to vascular risk factor education (standard care) alone.

METHODS

Phase II randomized, blinded, controlled trial of 134 participants without CVD with mild sleep impairment and blood pressure 130-160/<110 mm Hg. The primary outcome was the difference in the mean change in 24-hour ambulatory systolic blood pressure (SBP) over 8 weeks between intervention and control groups. Secondary outcomes included measures of sleep quality and psychosocial health, namely Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI), and Beck Anxiety Inventory (BAI).

RESULTS

Participants in the sleep intervention group showed significantly greater improvements in sleep quality, including ISI [difference in mean improvement 2.8; 95% confidence interval (CI), 1.3-4.4], PSQI (1.1; 95% CI, 0.1-2.2), sleep condition indicator (0.8; 95% CI, 0.2-1.4), and psychosocial health, including BDI (2.0; 95% CI, 0.3-3.7) and BAI (1.4; 95% CI, 0.02-2.8). The mean improvement in 24-hour ambulatory SBP did not differ between the sleep intervention (0.9 mm Hg) and control (0.8 mm Hg) arms, (difference in mean improvement 0.1; 95% CI, -3.4 to 3.2).

CONCLUSION

A simple, low-cost, web-delivered sleep intervention is feasible and significantly improves sleep quality and measures of psychosocial health in individuals with mild sleep impairment but does not result in short-term improvements in blood pressure.

Use of Oral Anticoagulant Therapy in Older Adults with Atrial Fibrillation After Acute Ischemic Stroke

OBJECTIVES

To explore barriers to anticoagulation in older adults with atrial fibrillation (AF) at high risk of stroke and to identify opportunities for interventions that might increase use of oral anticoagulants (OACs).

DESIGN

Retrospective cohort study.

SETTING

Two large community-based AF cohorts.

PARTICIPANTS

Individuals with ischemic stroke surviving hospitalization (N = 1,405, mean age 79).

MEASUREMENTS

Using structured chart review, reasons for nonuse of OAC were identified, and 1-year poststroke survival was assessed. Logistic regression was used to identify correlates of OAC nonuse.

RESULTS

Median CHA₂ DS₂ -VASc score was 5, yet 44% of participants were not prescribed an OAC at discharge. The most-frequent (nonmutually exclusive) physician reasons for not prescribing OAC included fall risk (26.7%), poor prognosis (19.3%), bleeding history (17.1%), participant or family refusal (14.9%), older age (11.0%), and dementia (9.4%). Older age (odds ratio (OR) = 8.96, 95% confidence interval (CI) = 5.01-16.04 for aged ≥85 vs <65) and disability (OR = 12.58, 95% CI = 5.82-27.21 for severe vs no deficit) were the most-important independent predictors of nonuse of OACs. By 1 year, 42.5% of those not receiving an OAC at discharge had died, versus 19.1% of those receiving an OAC (P < .001), far higher than recurrent stroke rates.

CONCLUSION

Despite very high stroke risk, more than 40% of participants were not discharged with an OAC. Dominant reasons included fall risk, poor prognosis, older age, and dementia. These individuals' high 1-year mortality rate confirmed their high level of comorbidity. To improve anticoagulation decisions and outcomes in this population, future research should focus on strategies to mitigate fall risk, improve assessment of risks and benefits of anticoagulation in individuals with AF, and determine whether newer anticoagulants are safer in complex elderly and frail individuals.

Abstract TMP90: Limited Use of Oral Anticoagulant Therapy in Patients with Atrial Fibrillation After Ischemic Stroke

Introduction: Oral anticoagulants (OAC) prevent stroke in patients with atrial fibrillation (AF) yet many are not prescribed OAC. Exploring barriers to OAC among AF patients at high stroke risk might identify opportunities to intervene.

Hypothesis: Old age, fall risk, and comorbidity will be strong barriers to use of OAC even among survivors of acute ischemic stroke (IS).

Methods: Inpatient and 1-year follow-up of patients sustaining an acute IS within the ATRIA and ATRIA-CVRN community-based AF cohorts (1996-2009; n=46,806). MD chart reviewers recorded use of OAC (warfarin) at discharge (96% complete), reasons for non-use, and modified Rankin disability score at discharge. Logistic regression identified patient features associated with non-use of OAC. Follow-up recorded 1-year mortality and recurrent IS.

Results: Of 1,405 AF patients discharged alive after IS, 44% (619) were not prescribed OAC despite a median CHA2DS2-VASc score of 5. The most frequent (non-mutually exclusive) reasons for non-use of OAC included risk of falls (26.7%), poor prognosis (19.3%), bleeding history (17.1%), patient/family refusal (14.9%), older age (11.0%) and dementia (9.4%). Logistic regression identified older age (OR 9.0, 95% CI 5.0-16.0 for age ≥85 vs. <65 yrs) and increased disability on discharge (OR 12.6, 95% CI 5.8-27.2 for severe deficit vs. no deficit) as the strongest independent clinical features associated with non-use of OAC at discharge. One-year mortality for those not receiving OAC at discharge was 43%--far higher than risk of recurrent IS (7.7%).

Conclusions: Despite very high stroke risk, >40% of AF/IS patients were not discharged on OAC. The dominant reasons for non-use of OAC were fall risk, poor prognosis, bleeding history, patient refusal, older age, and dementia. The high 1-year mortality rate confirmed these patients’ high comorbidity burden. Effective mitigation of fall risk or the improved safety profiles of newer anticoagulants might increase use of OACs. However, despite the substantial stroke protection benefit from OACs, understandable obstacles to OAC remain for many older and complex AF patients.

Does lowering blood pressure with antihypertensive therapy preserve independence in activities of daily living? A systematic review

BACKGROUND

Hypertension is a major risk factor for functional impairment. Dependence is an important related outcome for older adults, but outcomes in hypertension trials appear to focus primarily on major vascular events. This systematic review had 2 objectives: (i) to determine the proportion of randomized controlled trials (RCTs) evaluating antihypertensive therapies that reported a measure of a person's ability to carry out activities of daily living (ADL) and (ii) to evaluate the effect of blood pressure (BP)-lowering therapies on ability to carry out ADL compared with control therapy.

METHODS

We searched electronic databases, reference lists of relevant meta-analyses, and hypertension guidelines for clinical trials of adults with hypertension/prehypertension that were randomized to antihypertensive therapy or control for ≥1 year.

RESULTS

Of 2,924 citations screened, there were 93 eligible RCTs. One (1%) reported ADL as a primary outcome measure. Nine (10%) reported ADL as a secondary outcome. Of these, 6 used validated ADL scales, whereas 4 measured ADL within quality-of-life scales. Six trials with duration of ≥1 year (n = 12,663) were amenable to meta-analysis, despite use of different ADL scales. The odds of having difficulty with ADL was reduced by BP-lowering therapy compared with control therapy (odds ratio = 0.84; 95% confidence interval = 0.77-0.92; I (2) = 0%).

CONCLUSIONS

We identified few trials of antihypertensive therapy that reported ADL as an outcome measure, with heterogeneity in scales used. Antihypertensive therapy was associated with a lower risk of ADL impairment compared with control therapy. RCTs evaluating the effect of antihypertensive drugs on ADL in older adults with mild hypertension are required.

Transesophageal echocardiography in patients with cryptogenic ischemic stroke: a systematic review

BACKGROUND

The clinical utility of routine transesophageal echocardiography (TEE) for patients with unexplained ischemic stroke is controversial. We performed a systematic review to determine the frequency of detection of new cardiac findings in patients with cryptogenic ischemic stroke (IS) undergoing transesophageal echocardiography (TEE).

METHODS

Systematic review and meta-analysis of cohort studies of consecutive patients with "cryptogenic" IS undergoing TEE after routine etiologic workup. Patients were categorized into 2 groups: A (< 55 years) and B (≥ 55 years). Outcomes included proportion of patients with new TEE-detected cardiac findings and proportion of patients commenced on oral anticoagulation after TEE.

RESULTS

Twenty-seven studies were included (n = 5,653). We identified significant heterogeneity among studies and report a range of prevalence rates and I2 statistic as our primary analysis. Prevalence of individual cardiac findings on TEE varied significantly among studies; patent foramen ovale (A: 12.0%-57.8%, I2 = 89.9%; B: 3.9%-43.5%, I2 = 86.7%), atrial septal aneurysm (A: 0-48.9%, I2 = 91.9%; B: 3.5%-25.0%, I2 = 84.5%), left atrial thrombus (A: 0-10.9%, I2 = 61.1%; B: 0-21.2%, I2 = 91.7%), spontaneous echo contrast (A: 0-11.9%, I2 = 57.2%; B: 0-21.3%, I2 = 89.8%), and aortic atheroma (A: 0-9.6%, I2 = 53.8%; B: 2.8%-44.4%, I2 = 89.7%). Definitions of common findings were not provided for many studies. Five studies (n = 591) reported on the proportion of patients who were commenced on anticoagulant therapy after TEE (range 0-30.7%).

CONCLUSIONS

Routine TEE in patients with cryptogenic IS identifies cardiac findings in a large proportion. However, there is marked interstudy variation in the definition and prevalence of common findings. Transesophageal echocardiography-detected findings prompted the introduction of anticoagulant therapy in up to one-third of patients. However, these were mostly not for established guideline-based indications based on randomized controlled trial evidence. It is unclear if routine use of TEE in patients with cryptogenic IS is indicated.

Sleep to lower elevated blood pressure: study protocol for a randomized controlled trial

Background

Sleep is an essential component of good physical and mental health. Previous studies have reported that poor quality sleep is associated with an increased risk of hypertension and cardiovascular disease. Hypertension is the most common and important risk factor for cardiovascular disease, and even modest reductions in blood pressure can result in significant reductions in the risk of stroke and myocardial infarction. In this trial, we will determine the efficacy of an online sleep intervention in improving blood pressure, in participants with hypertension and poor sleep quality.

Methods

Trial design: Randomized-controlled, two-group, parallel, blinded, single-center, Phase II trial of 134 participants. Population and recruitment: Primary prevention population of participants with hypertension (systolic blood pressure, 130 to 160 mm Hg; diastolic blood pressure, <110 mm Hg) and poor sleep quality in a community setting. Intervention: Multicomponent online sleep intervention consisting of sleep information, sleep hygiene education, and cognitive behavioral therapy. Comparator: Standardized cardiovascular risk factor and lifestyle-education session (usual care). Primary outcome: Change in mean 24-hour ambulatory systolic blood pressure between baseline and 8-week follow-up. Hypertension has been selected as the primary outcome measure because of its robust association with both poor sleep quality and cardiovascular disease. Statistical analyses: Intention-to-treat analysis by using a linear mixed model.

Trial registration

ClinicalTrials.gov: NCT01809821, registered March 8, 2013.

Vascular risk factors, cardiovascular disease and functional impairment in community-dwelling adults

BACKGROUND

Older adults report preservation of functional independence as one of the most important constructs of successful ageing. Vascular risk factors may increase the risk of functional impairment due to clinical and subclinical vascular disease.

OBJECTIVE

To describe the association between vascular risk factors and impaired ability to perform daily living activities, independent of established cardiovascular disease.

METHODS

We conducted an analysis of the Clarity Cohort, which is a cross-sectional study of 9,816 community-dwelling Irish adults. Of the total cohort, 3,499 completed standardized self-reported health questionnaires, which included questions on activities of daily living. Functional impairment was defined as self-reported impairment in self-care, mobility or household tasks. Using logistic regression analyses, we determined the association between vascular risk factors and functional impairment, independent of demographics, prior coronary artery disease, stroke, congestive heart failure, and peripheral vascular disease.

RESULTS

Functional impairment was reported in 40.4% (n = 1,413) of the cohort overall and in 23% of those with established cardiovascular disease. The mean age was 66.2 ± 10.3 years, 52% of the cohort were aged over 65 and 45.6% were male. Some difficulty with instrumental activities of daily living was reported by 35.4% (n = 1,240) while 29.4% (n = 1,029) reported some difficulty with basic activities of daily living. On multivariable analysis, older age [OR 1.03 (1.02, 1.04) per year], current smoking [OR 1.43 (1.08, 1.89)], atrial fibrillation [OR 1.68 (1.07, 2.65)], former alcohol use [OR 1.87 (1.36, 2.57)] and prior stroke [OR 1.91 (1.24, 2.93)] were associated with an increased risk of functional impairment. Older age leaving education [OR 0.96 (0.94, 0.99)], non-use of alcohol [OR 0.76 (0.61, 0.93)] and increased high-density lipoprotein levels [OR 0.70 (0.56, 0.88)] were associated with reduced risk of functional impairment.

CONCLUSIONS

Independent of established cardiovascular disease, some vascular risk factors are associated with functional impairment. Modification of these risk factors is expected to have a large impact on preservation of functional independence through prevention of overt and covert vascular disease.

Novel Oral Anticoagulants: A Focused Review for Stroke Physicians

Novel oral anticoagulants provide an effective and convenient alternative to warfarin for stroke prevention in patients with atrial fibrillation. However, novel anticoagulants also present new challenges for stroke physicians, such as measurement of anticoagulant effect in emergency situations, use of thrombolysis in acute ischemic stroke, optimal timing of introduction of novel anticoagulants following acute ischemic stroke, and management of intracerebral hemorrhage. In this review, we propose pragmatic approaches to dealing with challenging management issues that will face stroke physicians who care for patients with acute stroke in the novel oral anticoagulant era.

Association of atrial fibrillation with mortality and disability after ischemic stroke

OBJECTIVE

We determined whether patient characteristics (age, sex, comorbidities), stroke severity, and quality of care explained a proportion of the association between atrial fibrillation (AF) and increased disability and mortality in patients with acute ischemic stroke.

METHODS

The study included a prospective cohort of consecutive patients admitted with acute ischemic stroke included in the Registry of the Canadian Stroke Network (July 1, 2003 to March 31, 2008). Multivariable logistic regression analyses were used to determine the magnitude of association between AF and modified Rankin score 4-5 at discharge, 30-day mortality, and 1-year mortality.

RESULTS

There were 10,528 patients admitted with acute ischemic stroke. AF was associated with an increased risk of severe disability and mortality, but the magnitude of association was substantially attenuated in the full multivariable models: modified Rankin score 4-5 at discharge (univariate odds ratio [OR] 1.74, 95% confidence interval [CI] 1.57-1.93; multivariable OR 1.19, 95% CI 1.03-1.36), 30-day mortality (univariate OR 2.52, 95% CI 2.25-2.84; multivariable OR 1.36, 95% CI 1.17-1.58), and 1-year mortality (univariate OR 2.41, 95% CI 2.19-2.66; multivariable OR 1.25, 95% CI 1.10-1.42). Older age and increased stroke severity explained most of the association between AF and poor stroke outcomes. We found no association between AF and poor stroke outcomes in patients receiving therapeutic preadmission oral anticoagulant therapy.

CONCLUSIONS

Older age and increased stroke severity explain most of the association between AF and poorer outcomes after acute ischemic stroke. Nonuse of oral anticoagulant therapy represents the most important modifiable care gap to mitigate the association between AF and poor outcomes after ischemic stroke.

Which risk factors are more associated with ischemic stroke than intracerebral hemorrhage in patients with atrial fibrillation?

BACKGROUND AND PURPOSE

The decision to prescribe oral anticoagulant therapy in patients with atrial fibrillation is based on an assessment of the competing risks of ischemic stroke and major bleeding, of which intracerebral hemorrhage (ICH) is the most important type. We sought to determine the comparative importance of risk factors for ischemic stroke and ICH in patients with acute stroke and atrial fibrillation with particular emphasis on risk factors common to both stroke types.

METHODS

Consecutive patients with acute ischemic stroke or ICH and atrial fibrillation included in the Registry of the Canadian Stroke Network constituted the cohort. Multivariable logistic regression analysis was used to determine the association between baseline risk factors and presentation with ICH versus ischemic stroke. Risk factors included: (1) those previously reported to be risk factors for both ischemic stroke and major bleeding (particularly ICH) ("shared" risk factors, including age, alcohol, hypertension, diabetes mellitus, renal impairment, prior stroke/transient ischemic attack and preadmission dementia); and (2) other risk factors associated with either stroke subtype alone.

RESULTS

A total of 3197 patients presented with atrial fibrillation and acute stroke, of which 12.2% presented with ICH. Of the "shared" risk factors, age (OR, 1.19; 95% CI, 1.06-1.34 per decade) and prior stroke/transient ischemic attack (OR, 1.45; 95% CI, 1.12-1.87) were more associated with ischemic stroke than ICH, whereas a history of hypertension (OR, 0.89; 95% CI, 0.68-1.17), diabetes mellitus (OR 1.23; 95% CI, 0.92-1.64), renal impairment (OR, 1.28; 95% CI, 0.95-1.71), and alcohol intake were not more strongly associated with either stroke subtype.

CONCLUSION

Of the risk factors known to be associated with both ischemic stroke and ICH in patients with atrial fibrillation, we found that none had a stronger association with ICH. Older age was more strongly associated with ischemic stroke than ICH.

Preventing cardiovascular disease in primary care: role of a national risk factor management program

BACKGROUND

Heartwatch, a structured risk factor modification program for secondary prevention of cardiovascular (CV) disease (CVD) in primary care, is associated with improvements in CV risk factors in participating patients. However, it is not known whether Heartwatch translates into reductions in clinically important CV events.

OBJECTIVE

The aim of the study was to determine the association between participation in Heartwatch and future risk of CV events in patients with CVD.

METHODS

The study consisted of a prospective cohort of 1,609 patients with CVD in primary care practices. Of these, 97.5% had data available on Heartwatch participation status, of whom 15.2% were Heartwatch participants. Cox proportional hazards models were used to determine the association between Heartwatch participation and risk of the CV composite (CV death, nonfatal myocardial infarction, heart failure, and nonfatal stroke). All-cause mortality and CV mortality were secondary outcome measures.

RESULTS

During follow-up, the CV composite occurred in 208 patients (13.6%). Of Heartwatch participants, 8.4% experienced the CV composite compared with 14.5% of nonparticipants (P = .003). Participation in Heartwatch was associated with a significantly reduced risk of the CV composite (hazard ratio [HR] 0.52, 95% CI, 0.31-0.87), CV mortality (HR 0.31, 95% CI, 0.11-0.89), and all-cause mortality (HR 0.32, 95% CI, 0.15-0.68). Heartwatch participation was also associated with greater reductions in mean systolic blood pressure (P = .047), mean diastolic blood pressure (P < .001), and greater use of secondary preventative therapies for CVD, such as lipid-lowering agents (P < .001), β-blockers (P < .001), and angiotensin-converting enzyme inhibitors (P < .001).

CONCLUSION

Heartwatch is associated with a reduced risk of major vascular events and improved risk factor modification, supporting its potential as a nationwide program for secondary prevention of CVD.

Abstract 2733: The Comparative Importance of `Shared' Risk Factors for Ischemic Stroke and Intracerebral Hemorrhage in Patients with Atrial Fibrillation

Background: Optimal prescribing of oral anticoagulants, for the prevention of stroke in patients with atrial fibrillation, requires clinicians to estimate the competing risk of ischemic stroke and intracerebral hemorrhage (ICH). However, a number of risk factors increase the risk of both ischemic stroke and ICH (e.g. age, hypertension and chronic renal disease), and it is unclear how these ‘shared’ risk factors should influence decisions on antithrombotic therapy.

Objective: To determine the comparative importance of risk factors for ischemic stroke and ICH in patients with atrial fibrillation, focusing primarily on risk factors included in the CHA2DS2VASC (risk of ischemic stroke) and HAS-BLED (risk of major bleeding) scores.

Methods: Prospective registry of 3,197 patients admitted with acute ischemic stroke or ICH and atrial fibrillation included in the Registry of the Canadian Stroke Network (Jul 03-Mar 08; 11 Regional Stroke Centers in Ontario, Canada). Multivariable analysis was used to determine the association between baseline risk factors (age, sex, history of hypertension, previous stroke or transient ischemic attack, history of congestive heart failure, history of vascular disease, hepatic impairment, current alcohol intake, history of diabetes mellitus, history of gastro-intestinal bleeding, renal impairment, admission INR and antiplatelet therapy) and risk of ischemic stroke versus ICH.

Results: Of 3,197 patients with atrial fibrillation and acute stroke, 2,806 (87.8%) presented with an ischemic stroke and 391 (12.2%) presented with an ICH. Of the ‘shared’ risk factors, age (OR 1.17; 95% CI 1.04-1.31 per decade) and previous history of stroke (OR 1.40; 95% CI 1.09-1.81) were associated with an increased risk of ischemic stroke relative to ICH, while a history of hypertension (OR 0.90; 95% CI 0.69-1.18) and renal impairment (OR 1.29; 0.96-1.72) were not associated with either stroke subtype, on multivariable analyses. Of the ‘non-shared’ risk factors, alcohol consumption of <2 units/day vs. no consumption (OR 1.61; 95% CI 1.24-2.09), female sex (OR 1.53; 95% CI 1.20-1.96) and a history of vascular disease (OR 1.73; 95% CI 1.30- 2.30) were associated with an increased risk of ischemic stroke relative to ICH. Elevated INR at the time of admission was a significant predictor of ICH, relative to ischemic stroke.

Conclusion: None of the ‘shared’ risk factors were stronger predictors of ICH compared to ischemic stroke, which has obvious implications for clinical practice. In particular, older age was more strongly associated with ischemic stroke than ICH in patients with atrial fibrillation, and therefore, should be considered as a factor favoring a decision to commence anticoagulant therapy.