Effective communications on invasive alien species: Identifying communication needs of Swedish domestic garden owners

Invasive alien species threaten biodiversity with domestic gardens acting as a major pathway for the introduction of alien species. Even though the Nordic region is not currently a hotspot for biological invasions, the number of invasions in the Nordic area has been predicted to increase due to climate change. Given a time lag between introduction and invasion, many non-invasive horticultural alien species already introduced into gardens may become invasive in the future. This study aimed to identify the communication needs of Swedish garden owners regarding their management of invasive alien species. A survey among domestic garden owners, informed by topic specialists and local area experts, and interviews with garden owners were conducted in three different bio-climatic areas in a latitudinal gradient across Sweden. The questions targeted invasive alien species and their relations to biodiversity loss and climate change, as well as measures taken to control these species. Analysing the survey data collected in relation to measures taken to control invasive species, Bayesian Additive Regression Tree (BART) modelling was used to identify geographically varying communication needs of the domestic garden owners. In all study areas, the garden owners' measures taken to control invasive alien species were correlated with their strength of beliefs in having experienced local biodiversity loss. A majority of the garden owners were, moreover, uncertain about the impact of climate change on the invasiveness of alien species. In addition, the garden owners' capacity for identifying invasive alien species was often in need of improvement, in particular with respect to the species Impatiens glandulifera, Reynoutria japonica and Rosa rugosa. The results suggest that the evidence-based guidelines for effective communications we developed, have the potential to help communicators meet the local communication needs of garden owners across Sweden, in relation to the management of invasive alien garden species.

Radiographers' perception of patient safety culture in radiology

INTRODUCTION

Radiographers play a central role in patient safety because of their knowledge of and responsibilities in relation to the imaging process. To maintain safe care, the workplace must create a safety culture that enables sustainable safety work.

AIM

This study aims to describe radiographers' perceptions of the patient safety culture in radiology units in Sweden.

METHODS

The Swedish Hospital Survey of Patients' Safety Culture (S-HSOPSC) was used to gather descriptive data from 171 Swedish registered radiographers working in five radiology clinics distributed across 15 units. Fifty-one questionnaire items and one open-ended question were analysed, comprising perceptions of the overall safety grade, the frequency of number of reported risks and events, and 14 composites regarding patient safety dimensions.

RESULTS

The radiographers' concerns surrounding the patient safety culture in their workplaces related to weaknesses regarding the safety dimensions "Staffing", "Frequency of error reporting", "Organizational learning - continuous improvement" and "Executive management support for patient safety". They perceived "Teamwork within the unit" to be a strength.

CONCLUSION

Despite some weaknesses in the patient safety culture, the radiographers perceived that the overall patient safety level was good, in part because of their ability to spot risks in time. The executive management, however, needed to improve their feedback on safety measures; and another reason for some weaknesses in the patient safety culture could be staffing issues such as lack of time for meetings for continuous improvement. Managers and leaders have a great responsibility to establish a patient safety culture through support and good leadership.

IMPLICATIONS FOR PRACTICE

An understanding of what creates a safety culture is important to prevent patient safety incidents.

A highly challenging balance training intervention for people with multiple sclerosis: a feasibility trial

BACKGROUND

Balance training interventions with a gradual progression of difficulty and highly challenging tasks designed specifically for people with multiple sclerosis (MS) are rare. The objective was to adapt a balance training intervention originally developed for Parkinson's disease through a co-design process and then conduct a pilot trial in MS to evaluate the feasibility of a large, full-scale study.

METHODS

Twelve people with MS with mild to moderate overall MS-disability were included in this single-group feasibility trial. Participants received one-hour training sessions twice or three times weekly for 10 weeks. The assessment included tests of physical and cognitive functioning and patient-reported quality of life-related outcomes. Data on feasibility aspects were collected at baseline and follow-up assessments and three times during the intervention period to inform the recruitment process, as well as to monitor retention and inclusion rates, study procedures, intervention delivery, and dynamic changes in the selected potential outcome measures. Progression criteria were used to determine whether to proceed to a full-scale trial. Descriptive statistics were used to present the data.

RESULTS

Out of six progression criteria, only retention and attendance at training sessions were not met. Reasons reported for not completing the intervention period mainly depended on external circumstances beyond the control of the study. In contrast, study procedures, intervention delivery, and intervention content (progression, adjustment, and control of challenge level of exercises) were considered feasible for a future, full-scale trial. The Mini-BESTest, which was used for the assessment of balance control, was considered suitable as the primary outcome in a full-scale trial with no ceiling or floor effects. Further, the Mini-BESTest showed a positive trend in outcome response with a median difference of 3.5 points between baseline and follow-up assessments. The power calculation performed suggests a feasible number of participants for recruitment.

CONCLUSIONS

Overall trial aspects and intervention delivery were deemed feasible for a full-scale trial, but adjustments are needed to increase retention and attendance.

Biochemical markers in vascular cognitive impairment associated with subcortical small vessel disease - A consensus report

Background

Vascular cognitive impairment (VCI) is a heterogeneous entity with multiple aetiologies, all linked to underlying vascular disease. Among these, VCI related to subcortical small vessel disease (SSVD) is emerging as a major homogeneous subtype. Its progressive course raises the need for biomarker identification and/or development for adequate therapeutic interventions to be tested. In order to shed light in the current status on biochemical markers for VCI-SSVD, experts in field reviewed the recent evidence and literature data.

Method

The group conducted a comprehensive search on Medline, PubMed and Embase databases for studies published until 15.01.2017. The proposal on current status of biochemical markers in VCI-SSVD was reviewed by all co-authors and the draft was repeatedly circulated and discussed before it was finalized.

Results

This review identifies a large number of biochemical markers derived from CSF and blood. There is a considerable overlap of VCI-SSVD clinical symptoms with those of Alzheimer’s disease (AD). Although most of the published studies are small and their findings remain to be replicated in larger cohorts, several biomarkers have shown promise in separating VCI-SSVD from AD. These promising biomarkers are closely linked to underlying SSVD pathophysiology, namely disruption of blood-CSF and blood–brain barriers (BCB-BBB) and breakdown of white matter myelinated fibres and extracellular matrix, as well as blood and brain inflammation. The leading biomarker candidates are: elevated CSF/blood albumin ratio, which reflects BCB/BBB disruption; altered CSF matrix metalloproteinases, reflecting extracellular matrix breakdown; CSF neurofilment as a marker of axonal damage, and possibly blood inflammatory cytokines and adhesion molecules. The suggested SSVD biomarker deviations contrasts the characteristic CSF profile in AD, i.e. depletion of amyloid beta peptide and increased phosphorylated and total tau.

Conclusions

Combining SSVD and AD biomarkers may provide a powerful tool to identify with greater precision appropriate patients for clinical trials of more homogeneous dementia populations. Thereby, biomarkers might promote therapeutic progress not only in VCI-SSVD, but also in AD.

Frequency Comparison of [Formula: see text] Ion Optical Clocks at PTB and NPL via GPS PPP

We used precise point positioning, a well-established GPS carrier-phase frequency transfer method to perform a direct remote comparison of two optical frequency standards based on single laser-cooled [Formula: see text] ions operated at the National Physical Laboratory (NPL), U.K. and the Physikalisch-Technische Bundesanstalt (PTB), Germany. At both institutes, an active hydrogen maser serves as a flywheel oscillator which is connected to a GPS receiver as an external frequency reference and compared simultaneously to a realization of the unperturbed frequency of the (2)S1/2(F=0)-(2)D3/2(F=2) electric quadrupole transition in [Formula: see text] via an optical femtosecond frequency comb. To profit from long coherent GPS-link measurements, we extrapolate the fractional frequency difference over the various data gaps in the optical clock to maser comparisons which introduces maser noise to the frequency comparison but improves the uncertainty from the GPS-link instability. We determined the total statistical uncertainty consisting of the GPS-link uncertainty and the extrapolation uncertainties for several extrapolation schemes. Using the extrapolation scheme with the smallest combined uncertainty, we find a fractional frequency difference [Formula: see text] of -1.3×10(-15) with a combined uncertainty of 1.2×10(-15) for a total measurement time of 67 h. This result is consistent with an agreement of the frequencies realized by both optical clocks and with recent absolute frequency measurements against caesium fountain clocks within the corresponding uncertainties.

MCI of different etiologies differ on the Cognitive Assessment Battery

OBJECTIVES

The study aims to investigate whether patients with mild cognitive impairment (MCI) who have significant vascular disease (MCI-vas) differ from those with no significant vascular disease (MCI-nov) in terms of cognitive profile when assessed with the cognitive assessment battery (CAB).

MATERIALS AND METHODS

Seventy patients clinically diagnosed with MCI were included in the study, 32 were classified as MCI-vas, and 38 as MCI-nov, together with 40 healthy controls. CAB consists of six short tests measuring speed and attention, memory, visuospatial functions, language, and executive functions.

RESULTS

The healthy controls performed better than both MCI groups on CAB. MCI-vas patients were significantly older and had fewer years of education than MCI-nov patients. When adjusted for age and education, MCI-vas performed significantly worse than MCI-nov on memory, language, and executive tests.

CONCLUSIONS

The results suggest that CAB can differentiate between MCI patients with and without vascular disease and that their cognitive profiles differ. Furthermore, CAB classified the patients as vascular and non-vascular MCI with good sensitivity and specificity.

Cognitive impairment in patients with stress-related exhaustion

Patients who seek medical care for stress-related mental health problems frequently report cognitive impairments as the most pronounced symptom. The purpose of the present study was to compare cognitive function in patients with stress-related exhaustion with that in healthy controls, using a comprehensive battery of cognitive tests. We also explored whether neuropsychological findings were related to severity of illness measured using the Shirom-Melamed burnout questionnaire and hospital anxiety and depression scale. Thirty-three patients (15 males) and 37 healthy controls (11 males), mean age 46 years [standard deviation (SD) 3.9] and 47 years (SD 4.3), respectively, were included in the final analysis. Five cognitive domains were assessed: (1) speed, attention and working memory, (2) learning and episodic memory, (3) executive functions, (4) visuospatial functions and (5) language. The most pronounced difference between patients and controls was seen on executive function, when tested with a multidimensional test, including aspects of speed, control and working memory. The patients also performed poorer on Digit span, measuring attention span and working memory as well as on learning and episodic memory, when measured as delayed recall and the difference between immediate and delayed recall. Delayed recall was the only test that was significantly related to severity of burnout symptoms among the patients. This could reflect poor cognitive sustainability in the patients with the highest burnout scores, as this particular test was the last one performed during the test session. This study clearly shows that cognitive impairment should be considered when evaluating and treating patients who seek medical care for stress-related exhaustion.

Brain atrophy accelerates cognitive decline in cerebral small vessel disease: the LADIS study

OBJECTIVE

To examine the independent contributions and combined interactions of medial temporal lobe atrophy (MTA), cortical and subcortical atrophy, and white matter lesion (WML) volume in longitudinal cognitive performance.

METHODS

A total of 477 subjects with age-related WML were evaluated with brain MRI and annual neuropsychological examinations in 3-year follow-up. Baseline MRI determinants of cognitive decline were analyzed with linear mixed models controlling for multiple confounders.

RESULTS

MTA and subcortical atrophy predicted significantly steeper rate of decline in global cognitive measures as well as compound scores for psychomotor speed, executive functions, and memory after adjusting for age, gender, education, lacunes/infarcts, and WML volume. Cortical atrophy independently predicted decline in psychomotor speed. WML volume remained significantly associated with cognitive decline even after controlling for the atrophy scores. Moreover, significant synergistic interactions were found between WML and atrophy measures in overall cognitive performance across time and the rate of cognitive decline. Synergistic effects were also observed between baseline lacunar infarcts and all atrophy measures on change in psychomotor speed. The main results remained robust after exclusion of subjects with clinical stroke or incident dementia, and after additional adjustments for progression of WML and lacunes.

CONCLUSIONS

Brain atrophy and WML are independently related to longitudinal cognitive decline in small vessel disease. MTA, subcortical, and cortical atrophy seem to potentiate the effect of WML and lacunes on cognitive decline.

Progression from mild to pronounced MCI is not associated with cerebrospinal fluid biomarker deviations

BACKGROUND/AIM

Detection of cerebrospinal fluid (CSF) biomarker deviations improve prediction of progression from mild cognitive impairment (MCI) to dementia. However, it is not settled whether the same pattern exists in patients progressing from very mild to more pronounced MCI. Given that neurodegenerative processes occur very early in the disease course, we also expected to find biomarker deviations in these patients.

METHODS

A total of 246 memory clinic patients with non-progressive (n = 161), progressive (n = 19), or converting (n = 66) MCI, 67 with stable dementia, and 80 controls were followed for 24 months. At baseline, CSF total tau (T-tau), β-amyloid 1-42 (Aβ42) and the light subunit of neurofilament protein (NFL) were determined.

RESULTS

Patients with converting MCI and stable dementia had lower CSF Aβ42 concentrations and higher T-tau concentrations and NFL in comparison with controls and non-progressive/progressive MCI (p < 0.0005). No differences were found between progressive and non-progressive MCI.

CONCLUSION

As expected, biomarker deviations predicted progression from MCI to dementia. Contrary to our hypothesis, progression from very mild MCI to more pronounced MCI was not reflected by biomarker deviations. The results suggest that the measured biomarkers are not early disease markers, or alternatively Alzheimer or vascular pathology is not the underlying cause in this patient group.

Age and diagnostic performance of Alzheimer disease CSF biomarkers

OBJECTIVES

Core CSF changes in Alzheimer disease (AD) are decreased amyloid β(1-42), increased total tau, and increased phospho-tau, probably indicating amyloid plaque accumulation, axonal degeneration, and tangle pathology, respectively. These biomarkers identify AD already at the predementia stage, but their diagnostic performance might be affected by age-dependent increase of AD-type brain pathology in cognitively unaffected elderly.

METHODS

We investigated effects of age on the diagnostic performance of CSF biomarkers in a uniquely large multicenter study population, including a cross-sectional cohort of 529 patients with AD dementia (median age 71, range 43-89 years) and 304 controls (67, 44-91 years), and a longitudinal cohort of 750 subjects without dementia with mild cognitive impairment (69, 43-89 years) followed for at least 2 years, or until dementia diagnosis.

RESULTS

The specificities for subjects without AD and the areas under the receiver operating characteristics curves decreased with age. However, the positive predictive value for a combination of biomarkers remained stable, while the negative predictive value decreased only slightly in old subjects, as an effect of the high AD prevalence in older ages.

CONCLUSION

Although the diagnostic accuracies for AD decreased with age, the predictive values for a combination of biomarkers remained essentially stable. The findings highlight biomarker variability across ages, but support the use of CSF biomarkers for AD even in older populations.

High white matter lesion load is associated with hippocampal atrophy in mild cognitive impairment

BACKGROUND

Mild cognitive impairment (MCI) is a heterogeneous condition suggested as a prodromal state of Alzheimer's disease (AD) and subcortical vascular dementia (SVD). Recent findings suggest that white matter lesions (WML) may be associated with hippocampal atrophy. The objective of the study was to examine hippocampal and WML volumes in MCI patients and to examine if WML were linked to hippocampal atrophy.

METHODS

The Gothenburg MCI study is a clinically based longitudinal study with biennial clinical assessments. The participants (n = 166) consist of 92 patients with stable MCI, 30 patients with converting MCI, and 44 healthy controls. WML volumes was measured manually using MRIcron. Automated segmentation of hippocampal and total white matter volumes was performed using FreeSurfer.

RESULTS

The patients converting from MCI to dementia had reduced hippocampal volume. Stable MCI patients had fewer WML and converting MCI patients had more WML compared to controls. Hippocampal volume was only correlated to WML volume (ρ = 0.57; p < 0.01) in the quartile (n = 42) with the most WML.

CONCLUSIONS

Hippocampal atrophy is present in both AD and SVD. Hippocampal volume was associated with WML volume only in the high WML quartile, suggesting that the WML volume must reach a threshold before hippocampal atrophy is seen.

High frequency of cognitive dysfunction before stroke among older people

OBJECTIVES

We examined cognitive functions before and in acute phase of stroke studying frequency and profile of cognitive impairment and relationships between cognitive status.

METHODS

Seventy-four patients with early phase after stroke and 49 healthy controls were included and examined using the Mini-Mental State Examination (MMSE) and a battery of neuropsychological tests. Cognitive status before stroke-onset was investigated using Cognitive Impairment Questionnaire.

RESULTS

Cognitive impairments were present in 96% of patients after stroke onset using the battery of neuropsychological tests and in 39% of patients using the MMSE, but in only 9% of controls. Seventy-six percent exhibited reduced executive function and 75% reduced psychomotor tempo. Cognitive dysfunction was present in 52% before stroke onset without any impact on the frequency of impairment in the various cognitive areas in early phase after stroke.

CONCLUSIONS

Cognitive impairment is frequent before the onset of stroke among older people and may partially explain the very high frequency of cognitive impairment observed after stroke onset.

No neurochemical evidence of brain injury after blast overpressure by repeated explosions or firing heavy weapons

BACKGROUND

Psychiatric and neurological symptoms are common among soldiers exposed to blast without suffering a direct head injury. It is not known whether such symptoms are direct consequences of blast overpressure.

OBJECTIVE

To examine if repeated detonating explosions or firing if of heavy weapons is associated with neurochemical evidence of brain damage.

MATERIALS AND METHODS

Three controlled experimental studies. In the first, army officers were exposed to repeated firing of a FH77B howitzer or a bazooka. Cerebrospinal fluid (CSF) was taken post-exposure to measure biomarkers for brain damage. In the second, officers were exposed for up to 150 blasts by firing a bazooka, and in the third to 100 charges of detonating explosives of 180 dB. Serial serum samples were taken after exposure. Results were compared with a control group consisting of 19 unexposed age-matched healthy volunteers.

RESULTS

The CSF biomarkers for neuronal/axonal damage (tau and neurofilament protein), glial cell injury (GFAP and S-100b), blood-brain barrier damage (CSF/serum albumin ratio) and hemorrhages (hemoglobin and bilirubin) and the serum GFAP and S-100b showed normal and stable levels in all exposed officers.

DISCUSSION

Repeated exposure to high-impact blast does not result in any neurochemical evidence of brain damage. These findings are of importance for soldiers regularly exposed to high-impact blast when firing artillery shells or other types of heavy weapons.

Red and processed meat consumption and risk of ovarian cancer: a dose-response meta-analysis of prospective studies

Background:

During the last decade, the epidemiological evidence on consumption of meat and risk of ovarian cancer has accumulated.

Methods:

We assessed the relationship between red and processed meat consumption and risk of ovarian cancer with a dose-response meta-analysis. Relevant prospective cohort studies were identified by searching the PubMed and EMBASE databases through 21 January 2011, and by reviewing the reference lists of retrieved articles. Study-specific relative risk (RR) estimates were combined using a random-effects model.

Results:

Eight cohort studies were included in the meta-analysis. The summary RR for an intake increment of 100 g per week was 1.02 (95% confidence interval (CI), 0.99–1.04) for red meat and 1.05 (95% CI, 0.98–1.14) for processed meat. For an intake increment of four servings per week, the summary RR of ovarian cancer was 1.07 (95% CI, 0.97–1.19) for red meat (100 g per serving) and 1.07 (95% CI, 0.97–1.17) for processed meat (30 g per serving).

Conclusion:

Results from this dose-response meta-analysis suggest that red and processed meat consumption is not associated with risk of ovarian cancer. Although a lower consumption of red and processed meat may offer protection against other types of cancer, other interventions are needed to reduce the risk of ovarian cancer.

Combination of hippocampal volume and cerebrospinal fluid biomarkers improves predictive value in mild cognitive impairment

BACKGROUND

Mild cognitive impairment (MCI) is a heterogeneous condition, and the prognosis differs within the group. Recent findings suggest that hippocampal volumetry and CSF biomarkers can be used to predict which MCI patients have an underlying neurodegenerative disorder.

OBJECTIVE

To examine the combined predictive value of hippocampal volume and CSF levels of total tau (T-tau) and beta-amyloid(42) (Abeta(42)) in stable and converting MCI patients. The participants (n = 68) included patients with MCI at baseline and who converted to dementia by the time of the 2-year follow-up (n = 21), stable MCI patients (n = 21) and healthy controls (n = 26).

METHODS

The Göteborg MCI study is a clinically based longitudinal study with biannual clinical assessments. Hippocampal volumetry was performed manually, based on data from the 0.5-tesla MRI investigations at baseline. Baseline CSF levels of T-tau and Abeta(42) were measured using commercially available, enzyme-linked immunosorbent assays.

RESULTS

The converting MCI group had significantly smaller left hippocampi, lower CSF Abeta(42) and higher T-tau compared to both the stable MCI group and the healthy controls. Multivariate analysis revealed that a combination of the variables outperformed the prognostic ability of the separate variables.

CONCLUSIONS

Hippocampal volumes supplement the prognostic accuracy of CSF Abeta(42) and T-tau in MCI.

White matter changes and diabetes predict cognitive decline in the elderly: the LADIS study

OBJECTIVE

We aimed to study if age-related white matter changes (WMC) and vascular risk factors were predictors of cognitive decline in elderly subjects with WMC living independently.

METHODS

The Leukoaraiosis and Disability prospective multinational European study (LADIS) evaluates the impact of WMC on the transition of independent elderly subjects into disability. Independent elderly were enrolled due to the presence of WMC. Subjects were evaluated yearly during 3 years with a comprehensive clinical protocol and a neuropsychological battery. Additionally, dementia, subtypes of dementia, and cognitive decline without dementia were classified according to usual clinical criteria. MRI was performed at entry and at the end of the study.

RESULTS

A total of 639 subjects were included (74.1 +/- 5 years, 55% women, 9.6 +/- 3.8 years of schooling). At end of follow-up, 90 patients had dementia and 147 had cognitive impairment no dementia. Using Cox regression analysis, WMC severity independently predicted cognitive decline (dementia and not dementia), independently of age, education, and medial temporal atrophy (MTA). Diabetes at baseline was the only vascular risk factor that independently predicted cognitive decline during follow-up, controlling for age, education, WMC severity, and temporal atrophy. Considering subtypes of dementia, Alzheimer disease (AD) was predicted only by MTA, while vascular dementia was predicted by previous stroke, WMC severity, and MTA.

CONCLUSION

WMC severity and diabetes are independent predictors of cognitive decline in an initially nondisabled elderly population. Vascular dementia is predicted by previous stroke and WMC, while AD is predicted only by MTA.

Cognitive Impairment Questionnaire (CIMP-QUEST): reported topographic symptoms in MCI and dementia

OBJECTIVE

The Cognitive Impairment Questionnaire (CIMP-QUEST) is an instrument based on information obtained by key informants to identify symptoms of dementia and dementia-like disorders. The questionnaire consists of three subscales reflecting impairment in parietal-temporal (PT), frontal (F) and subcortical (SC) brain regions. The questionnaire includes a memory scale and lists non-cognitive symptoms. The reliability and validity of the questionnaire were examined in 131 patients with mild cognitive impairment (MCI) or mild dementia at a university-based memory unit.

METHODS/RESULTS

Cronbach alpha for all subscales was calculated at r = 0.90. Factor analysis supported the tri-dimensionality of CIMP-QUEST's brain region-oriented construct. Test-retest reliability for a subgroup of cognitively stable MCI-patients (n = 25) was found to be r = 0.83 (P = 0.0005). The correlation between the score on the cognitive subscales (PT + F + M) and Informant Questionnaire on Cognitive Decline in the Elderly was r = 0.83 (P = 0.0005, n = 123). The memory subscale correlated significantly with episodic memory tests, the PT subscale with visuospatial and language-oriented tests, and the SC and F subscales with tests of attention, psychomotor tempo and executive function.

CONCLUSIONS

CIMP-QUEST has high reliability and validity, and provides information about cognitive impairment and brain region-oriented symptomatology in patients with MCI and mild dementia.

Apathy is a prominent neuropsychiatric feature of radiological white-matter changes in patients with dementia

OBJECTIVE

Cerebral white-matter changes (WMCs) are frequently found in dementia and have been proposed to be related to vascular factors and a certain symptomatological profile. However, few studies have included both vascular factors and a broad spectrum of cognitive, neurological and psychiatric symptoms, easily detectable by the physician in the everyday clinical work. The objective was to study the relationships between WMCs on MRI/CT and neuropsychiatric symptoms and vascular factors in patients with cognitive impairment.

METHODS

One hundred and seventy-six patients with Alzheimer's disease, vascular dementia, mixed dementia, and mild cognitive impairment were included. All patients underwent a standardized examination including medical history, clinical examinations, laboratory tests and brain imaging (CT or MRI). The identification and severity degree of WMCs was assessed blindly to clinical findings, using a semi-quantitative scale. For statistical analyses, patients were grouped based on absence or presence of WMCs. Significant variables in bivariate analyses were included as predictors in stepwise multiple logistic regression analyses.

RESULTS

Bivariate analyses showed significant associations between WMCs and age, gender, blood pressure, hypertension, ischaemic heart disease and TIA/RIND. Furthermore, there were significant associations between WMCs and apathy, mental slowness, disinhibition, gait disturbance and focal neurologic symptoms. The multivariate logistic model revealed apathy, mental slowness and age as the most consistent predicting factors for WMCs, together with MRI as a radiological method for the detection of WMCs.

CONCLUSIONS

The findings indicate that WMCs in patients with dementia are associated with a dysexecutive-related behavioural symptom profile, vascular factors related to small and large vessel diseases and age.

Relationship between baseline white-matter changes and development of late-life depressive symptoms: 3-year results from the LADIS study

BACKGROUND

Growing evidence suggests that cerebral white-matter changes and depressive symptoms are linked directly along the causal pathway. We investigated whether baseline severity of cerebral white-matter changes predict longer-term future depressive outcomes in a community sample of non-disabled older adults.

METHOD

In the Leukoaraiosis and Disability in the Elderly (LADIS) study, a longitudinal multi-centre pan-European study, 639 older subjects underwent baseline structural magnetic resonance imaging (MRI) and clinical assessments. Baseline severity of white-matter changes was quantified volumetrically. Depressive outcomes were assessed in terms of depressive episodes and depressive symptoms, as measured by the Geriatric Depression Scale (GDS). Subjects were clinically reassessed annually for up to 3 years. Regression models were constructed to determine whether baseline severity of white-matter changes predicted future depressive outcomes, after controlling for confounding factors.

RESULTS

Baseline severity of white-matter changes independently predicted depressive symptoms at both 2 (p<0.001) and 3 years (p=0.015). Similarly, white-matter changes predicted incident depression (p=0.02). Over the study period the population became significantly more disabled (p<0.001). When regression models were adjusted to account for the influence of the prospective variable transition to disability, baseline severity of white-matter changes no longer predicted depressive symptoms at 3 years (p=0.09) or incident depression (p=0.08).

CONCLUSIONS

Our results support the vascular depression hypothesis and strongly implicate white-matter changes in the pathogenesis of late-life depression. Furthermore, the findings indicate that, over time, part of the relationship between white-matter changes and depression may be mediated by loss of functional activity.

Cognitive reserve in relation to abeta42 in patients converting from MCI to dementia - a follow-up report

The concept of the cognitive reserve (CR) hypothesizes that premorbid factors such as education enable compensation for the manifestation of brain pathology. Accordingly, pathology should be more prominent in individuals with higher CR before becoming clinically apparent. Previously, we found that patients subsequently converting to dementia with higher CR had lower concentrations of amyloid beta 42 (abeta42) as compared to patients with lower CR. However, the interaction between time, biomarkers, neuropsychological performance and CR is yet to be established.

OBJECTIVE

To study the relation between biomarkers, neuropsychological performance and CR longitudinally.

METHOD

A mixed between-within subject analysis of variance was performed for longitudinal analysis. Paired t tests were used for within group comparisons.

RESULTS

Patients with higher CR (n = 15) had significantly lower concentrations of abeta42 at both time points compared to those with medium (n = 23) and lower CR (n = 28). Also, abeta42 concentrations decreased significantly from baseline to follow-up in patients with higher and medium CR. Groups performed comparably on neuropsychological tests.

CONCLUSION

This study provides further support for the applicability of abeta42 as a substitute for pathology in relation to CR. Also, abeta42 reflects the disease progression in patients with higher and medium CR.

Transthyretin as a potential CSF biomarker for Alzheimer's disease and dementia with Lewy bodies: effects of treatment with cholinesterase inhibitors

BACKGROUND

Previous studies have indicated that transthyretin (TTR) levels in cerebrospinal fluid (CSF) are altered in depression and dementia. The present study aimed to investigate whether CSF TTR can be used to discriminate between patients with Alzheimer's disease (AD) and patients with dementia with Lewy bodies (DLB) with or without medication, as well as to reveal whether CSF TTR correlates with depression in dementia.

METHODS

CSF samples from 59 patients with AD, 13 patients with DLB and 13 healthy controls were collected, and biochemical analysis was performed. Subjects were assessed for the presence of depression.

RESULTS

No significant differences in CSF TTR were found between AD, DLB, and control subjects or between depressed and non-depressed dementia patients. Interestingly, we found a significant reduction in CSF TTR (14%) in AD patients who were medicated with cholinesterase inhibitors compared to those AD patients who were not.

CONCLUSIONS

Significant reductions in CSF TTR were found after cholinesterase inhibitor treatment in patients with AD compared to untreated individuals. CSF TTR was unaltered in patients with DLB and had no relationship to depression in the present cohort with dementias.

Deep frontal and periventricular age related white matter changes but not basal ganglia and infratentorial hyperintensities are associated with falls: cross sectional results from the LADIS study

BACKGROUND

Global age related white matter changes (ARWMC) are associated with progressive gait disturbances and falls, hypothesised to result from interruptions of cortico-subcortical circuits controlling balance, posture and locomotion.

METHODS

The location of ARWMC in a large cohort of elderly non-disabled individuals with reported falls was analysed, using the cross sectional data of the Leukoaraiosis and Disability (LADIS) study. Detailed anatomical distributions of ARWMC assessed by MRI studies were analysed with respect to falls and balance performance.

RESULTS

The severity of global ARWMC was significantly associated with a history of falls in the year prior to study inclusion (22.2% in the mild, 31.6% in the moderate and 37.3% in the severe ARWMC group according to the Fazekas scale; p = 0.002). Analysing the anatomical distribution of ARWMC, using the semiquantitative Scheltens scale, in multivariate analysis, periventricular (p = 0.006) and frontal deep (p = 0.033) ARWMC were independently associated with falls. Furthermore, logistic regression identified frontal deep (p = 0.003) ARWMC, but not basal ganglia and infratentorial hyperintensities, as significantly associated with balance disturbances.

CONCLUSION

The association of frontal and periventricular ARWMC with falls supports the hypothesis that interruption of frontal subcortical motor circuits lead to balance disturbances and hence to an increased risk for falls in ARWMC.

Biomarkers in relation to cognitive reserve in patients with mild cognitive impairment--proof of concept

BACKGROUND

The concept of the cognitive reserve (CR) posits that factors such as education enable compensation for the effect of brain pathology. Consequently, pathology should be more pronounced in individuals with higher CR before becoming clinically apparent. Biomarkers such as total tau (t-tau) and beta-amyloid 42 (Abeta42) may be surrogates for pathology in relation to CR in patients with neurodegenerative disease.

OBJECTIVE

To examine the applicability of biomarkers as surrogates for pathology in relation to the CR in patients with mild cognitive impairment (MCI) either converting to dementia or remaining stable at follow-up.

METHOD

Comparisons of baseline t-tau, Abeta42, educational years and global cognition for MCI patients either converting to dementia (n = 57) or remaining stable (n = 91) were made. Patients converting to dementia were grouped on the basis of educational level and compared considering biomarkers and neuropsychological tests.

RESULTS

Stable MCI patients were better educated, performed better cognitively, had higher Abeta42 levels and lower levels of t-tau. Converting MCI patients with higher education had lower levels of Abeta42 and performed equally in neuropsychological tests compared to those with lower education.

CONCLUSION

Our results suggest that highly educated MCI patients subsequently converting to dementia display more amyloid pathology.

Quantifying time awake posturographically

Although sleepiness is a major risk factor in traffic and occupational accidents, convenient, quantitative, and commercial sleepiness testing is lacking. The issue is relevant to policymakers concerned with legislation for, and surveillance of, traffic- and occupational safety. This work suggested and examined posturographic sleepiness testing for instrumentation purposes. In 63 subjects--for whom we tested balance with a force platform during sustained waking for maximum 36 h--sustained waking impaired the balance. The sustained waking explained 60% of the diurnal balance variations, whereas the time of day explained 40% of the balance variations. The first finding -that balance depends on the subject's time awake (TA)- allowed to posturographically estimate the subjects' TA with 86% accuracy and 97% precision. Results also show that balance scores tested at 13:30 hours serve as a threshold to detect excessive sleepiness. This work provides guidelines for a posturographic sleepiness tester.

Evolution of Abeta42 and Abeta40 levels and Abeta42/Abeta40 ratio in plasma during progression of Alzheimer's disease: a multicenter assessment

OBJECTIVE

To better understand the seemingly contradictory plasma beta-amyloid (Abeta) results in Alzheimer's disease (AD) patients by using a newly developed plasma Abeta assay, the INNO-BIA plasma Abeta forms, in a multicenter study.

METHODS

A combined retrospective analysis of plasma Abeta isoforms on mild cognitive impairment (MCI) from three large cross-sectional studies involving 643 samples from the participating German and Swedish centers.

RESULTS

Detection modules based on two different amino (N)-terminal specific Abeta monoclonal antibodies demonstrated that Abeta in plasma could be reliable quantified using a sandwich immunoassay technology with high precision, even for low Abeta42 plasma concentrations. Abeta40 and Abeta42 concentrations varied consistently with the ApoE genotype, while the Abeta42/Abeta40 ratio did not. Irrespective of the decrease of the Abeta42/Abeta40 ratio with age and MMSE, this parameter was strongly associated with AD, as defined in this study by elevated hyperphosphorylated (P-tau181P) levels in cerebrospinal fluid (CSF).

CONCLUSION

A highly robust assay for repeatedly measuring Abeta forms in plasma such as INNO-BIA plasma Abeta forms might be a useful tool in a future risk assessment of AD.

Reduced cerebrospinal fluid BACE1 activity in multiple sclerosis

Background

Cell and animal experiments have shown that β-site APP-cleaving enzyme 1 (BACE1) may be involved in myelination.

Objective

Here, we assess the association of cerebrospinal fluid (CSF) BACE1 activity with multiple sclerosis (MS).

Methods

BACE1 activity and levels of secreted amyloid precursor protein (APP) and amyloid-β (Aβ) isoforms were analyzed in CSF from 100 patients with MS and 114 neurologically healthy controls. Patients with systemic lupus erythematosus (SLE), 26 with and 41 without cerebral engagement, were also included to enable comparisons with regards to another autoimmune disease. A subset of patients with MS and controls underwent a second lumbar puncture after 10 years.

Results

MS patients had lower CSF BACE1 activity than controls ( P = 0.03) and patients with cerebral SLE ( P < 0.001). Patients with cerebral SLE had higher BACE1 activity than any other group ( P < 0.05 for all comparisons). BACE1 activity correlated with the different amyloid markers in all study groups. BACE1 activity decreased over 10 years in the MS group ( P = 0.039) and correlated weakly with clinical disease severity scores in an inverse manner.

Conclusions

These results suggest an involvement of BACE1 in the MS disease process.

Self-perceived memory impairment and cognitive performance in an elderly independent population with age-related white matter changes

OBJECTIVES

To determine whether self-perceived memory impairment is associated with the severity of white matter changes (WMC) and is related to cognitive impairment.

METHODS

Data were drawn from the multinational Leukoaraiosis and Disability Study (LADIS), which investigates the impact of WMC on global functioning. WMC severity was rated using the Fazekas scale. Medial temporal lobe atrophy (MTA) was scored visually and mean values were calculated. The neuropsychological battery consisted of the Mini-Mental State Examination, a modified version of the VADAS-Cog, Trail making and Stroop tests. A question about self-perceived memory impairment was used as a measure for presence of memory complaints. Cognitive performance was analysed test-by-test and in three main domains: memory, executive functions and speed/motor control. The Geriatric Depression Scale (GDS) was used as a measure of depressive symptoms.

RESULTS

Six hundred and thirty-eight subjects were included in this study. No association was found between memory complaints and the severity of WMC. Subjects with memory complaints (n = 399) had a higher GDS score [t((637)) = -7.15; p<0.02] and performed worse on almost all cognitive tests and on the three cognitive domains. Multiple linear regression showed that the worse performance on the memory domain was associated with memory complaints independently of depressive symptoms, WMC severity and MTA (R(2) = 0.183; F = 17.09, beta = -0.126; p<0.05).

CONCLUSION

In a sample of non-disabled elderly subjects with WMC, self-perceived memory impairment is significantly associated with objective memory impairment independently of the WMC severity, depressive symptoms and MTA.

Small baseline volume of left hippocampus is associated with subsequent conversion of MCI into dementia: the Göteborg MCI study

BACKGROUND

Earlier studies have reported that hippocampal atrophy can to some extent predict which patients with mild cognitive impairment (MCI) will subsequently convert to dementia, and that converters have an enhanced rate of hippocampal volume loss.

OBJECTIVE

To further validate the hypothesis that hippocampal atrophy predicts conversion from MCI to dementia, to relate baseline hippocampal volume to different forms of dementia, and to investigate the role of hippocampal side differences and rate of volume loss over time.

PATIENTS

The subjects (N=68) include patients with MCI at baseline and progression to dementia at the two-year follow-up (N=21), stable MCI patients (N=21), and controls (N=26). Among the progressing patients, 13 were diagnosed as having AD.

METHODS

The Göteborg MCI study is a clinically based longitudinal study with biannual clinical assessments. Hippocampal volumetry was performed manually on the MRI investigations at baseline and at the two-year follow-up.

RESULTS

Hippocampal volumetry could predict conversion to dementia in both the AD and the non-AD subgroup of converters. Left hippocampal volume in particular discriminated between converting and stable MCI. Cut off points for individual discrimination were shown to be potentially useful. The converting MCI group had a significantly higher rate of hippocampal volume loss as compared to the stable MCI group.

CONCLUSIONS

In MCI patients, hippocampal volumetry at baseline gives prognostic information about possible development of AD and non-AD dementia. Contrary to earlier studies, we found that left hippocampal volume has the best predictive power. Reliable predictions appear to be possible in many individual cases.

Association of gait and balance disorders with age-related white matter changes: the LADIS study

OBJECTIVE

In the Leukoaraiosis and Disability (LADIS) Study, 11 European centers are evaluating the role of age-related white matter changes (ARWMC) as an independent determinant of the transition to disability in the elderly (65 to 84 years). We aimed at determining the influence of ARWMC on different objective measures of gait and balance.

METHODS

Six hundred thirty-nine nondisabled individuals were prospectively enrolled and are being followed-up for 3 years. Subjects are graded in three standardized categories of ARWMC (mild, moderate, and severe) according to central MRI reading. Quantitative tests of gait and balance include the Short Physical Performance Battery (SPPB; range: 0 [poor] to 12 [normal]), a timed 8-m walk, and a timed single leg stance test.

RESULTS

In cross-sectional analysis, deficiencies in gait and balance performance were correlated with the severity of ARWMC (SPPB: 10.2 +/- 2.1 in the mild, 9.9 +/- 2.0 in the moderate, 8.9 +/- 2.6 in the severe group; p < 0.001). Walking speed correlated with the severity of ARWMC (1.24 +/- 0.28 m/second in the mild, 1.18 +/- 0.32 m/second in the moderate, and 1.09 +/- 0.31 m/second in the severe group; p < 0.001). Balance was best in individuals with mild ARWMC (single leg stance time: 18.9 +/- 10.8 seconds) compared with moderate and severe ARWMC (16.4 +/- 10.8 and 13.6 +/- 11.2 seconds) (p < 0.001). Physically inactive individuals had a higher risk of a pathologic SPPB score (moderate vs mild ARWMC: odds ratio 1.60, 95% CI 1.02 to 2.52; severe vs mild ARWMC: odds ratio 1.75, 95% CI 1.09 to 2.80).

CONCLUSIONS

Our findings support a strong association between the severity of age-related white matter changes and the severity of gait and motor compromise. Physical activity might have the potential to reduce the risk of limitations in mobility.

Multicenter assessment of CSF-phosphorylated tau for the prediction of conversion of MCI

BACKGROUND

The measurement of hyperphosphorylated tau (p-tau) in CSF has been proposed as a biomarker candidate for the prediction of Alzheimer disease (AD) in patients with mild cognitive impairment (MCI). However, a standard quantitative criterion of p-tau has not been evaluated.

OBJECTIVE

To assess in a multicenter study the predictive accuracy of an a priori defined criterion of tau phosphorylated at threonine 231 (p-tau(231)) for the prediction of conversion from MCI to AD during a short-term observation interval.

METHODS

The study included 43 MCI converters, 45 stable MCI (average follow-up interval = 1.5 years), and 57 healthy controls (at baseline only). Subjects were recruited at four international expert sites in a retrospective study design. Cox regression models stratified according to center were used to predict conversion status. Bootstrapped 95% CIs of classification accuracy were computed.

RESULTS

Levels of p-tau(231) were a significant predictor of conversion (B = 0.026, p = 0.001), independent of age, gender, Mini-Mental State Examination, and ApoE genotype. For an a priori-defined cutoff point (27.32 pg/mL), sensitivity ranged between 66.7 and 100% and specificity between 66.7 and 77.8% among centers. The bootstrapped mean percentage of correctly classified cases was 79.95% (95% CI = 79.9 to 80.00%). Post hoc defined cutoff values yielded a mean bootstrapped classification accuracy of 80.45% (95% CI = 80.24 to 80.76%).

CONCLUSIONS

An a priori defined cutoff value of p-tau(231) yields relatively stable results across centers, suggesting a good feasibility of a standard criterion of p-tau(231) for the prediction of Alzheimer disease.

Posterior cortical brain dysfunction in cognitively impaired patients with Parkinson's disease--a rCBF scintigraphy study

OBJECTIVES

The aim of the study was to visualize cortical function in Parkinson's patients with various degrees of cognitive impairment.

MATERIALS AND METHODS

Thirty-seven patients with Parkinson's disease and three with Parkinson plus syndromes underwent cognitive assessment and rCBF using (99m)TC-HMPAO-SPECT.

RESULTS

Almost no regional reductions in cerebral blood flow were seen in patients without cognitive impairment (n = 16). Limited, mainly posterior, blood flow reductions were seen in patients with mild cognitive impairment (n = 14), whereas the reductions were extensive and bilaterally symmetric, involving both anterior and posterior brain regions in patients with dementia (n = 10).

CONCLUSIONS

The findings suggest a widespread cortical, mainly posterior type of dysfunction and a relationship between the degree of cognitive impairment and the magnitude of the dysfunction.

Model-based posturographic sleepiness monitor tested on 20 subjects

A previous posturographic force platform study verified that human balance deteriorates as a function of time awake (TA). It found that TA can be estimated with +/-2.5 h accuracy using 30 s trial length. For a fast, reliable and convenient sleepiness monitor even better TA estimation accuracy and shorter trial length is needed. We continued this quest by modeling the quiet stance test situation with a single-link inverted pendulum model (SLIPM). The center-of-mass (COM) trace in the AP (anterior-posterior) direction was calculated from the measured center-of-pressure (COP) trace. The sway angle theta, ankle torque tau and the horizontal force F acting on the COM were calculated from the SLIP equations--each analyzed with 13 different sway measures, i.e. variables that correlate with TA. The effect of circadian rhythm was separated from the sway measures. Twenty subjects' sway measures were analyzed. The SLIPM-based posturographic averaged TA estimation accuracy improved to +/-2.3 h. The trial length could be shortened to 21 s.

Prediction and longitudinal study of CSF biomarkers in mild cognitive impairment

OBJECTIVES

To longitudinally evaluate five cerebrospinal fluid (CSF) biomarkers in the transition from mild cognitive impairment (MCI) to Alzheimer's disease (AD).

METHODS

A baseline and 2-year follow-up clinical and CSF study of 86 subjects, including 22 MCI patients that declined to AD (MCI-AD), 43 MCI that did not deteriorate (MCI-MCI) and 21 controls (NL-NL). All subjects were studied for total and phosphorylated tau (T-tau, P-tau(231)), amyloid beta (Abeta) Abeta(42)/Abeta(40) ratio, isoprostane (IP) as well as P-tau(231)/Abeta(42/40) and T-tau/Abeta(42/40) ratios.

RESULTS

At baseline and at follow-up MCI-AD showed higher levels P-tau(231), T-tau, IP, P-tau(231)/Abeta(42/40) and T-tau/Abeta(42/40) ratios and lower Abeta(42)/Abeta(40) than MCI-MCI or NL-NL. Baseline P-tau(231) best predicted MCI-AD (80%, p<0.001) followed in accuracy by P-tau(231)/Abeta(42/40) and T-tau/Abeta(42/40) ratios (both 75%, p's<0.001), T-tau (74%, p<0.001), Abeta(42)/Abeta(40) (69%, p<0.01), and IP (68%, p<0.01). Only IP showed longitudinal effects (p<0.05).

CONCLUSIONS

P-tau(231) is the strongest predictor of the decline from MCI to AD. IP levels uniquely show longitudinal progression effects. These results suggest the use of CSF biomarkers in secondary prevention trials.

White matter changes and late-life depressive symptoms: longitudinal study

BACKGROUND

Evidence from cross-sectional studies suggests a link between cerebral age-related white matter changes and depressive symptoms in older people, although the temporal association remains unclear.

AIMS

To investigate age-related white matter changes on magnetic resonance imaging (MRI) as an independent predictor of depressive symptoms at 1 year after controlling for known confounders.

METHOD

In a pan-European multicentre study of 639 older adults without significant disability, MRI white matter changes and demographic and clinical variables, including cognitive scores, quality of life, disability and depressive symptoms, were assessed at baseline. Clinical assessments were repeated at 1 year.

RESULTS

Using logistic regression analysis, severity of white matter changes was shown to independently and significantly predict depressive symptoms at 1 year after controlling for baseline depressive symptoms, quality of life and worsening disability (P<0.01).

CONCLUSIONS

White matter changes pre-date and are associated with the development of depressive symptoms. This has implications for treatment and prevention of depression in later life.

Amyloid beta1-40 quantification in CSF: comparison between chromatographic and immunochemical methods

BACKGROUND/AIMS

Amyloid beta (Abeta) is the principal component of senile plaques, one of the hallmarks of Alzheimer's disease (AD). Evidence is accumulating that soluble aggregates (oligomers) of Abeta are important in the pathogenesis of AD.

METHODS

We compared three different methods for quantification of the 40 amino acid form of Abeta (Abeta40) in CSF, two based on antibodies [ELISA and surface-enhanced laser desorption/ionization-time of flight (SELDI-TOF) with antibody-coated arrays] and one based on direct binding of proteins to a protein array [SELDI-TOF and immobilized metal affinity [copper] (IMAC30)].

RESULTS

CSF Abeta40 concentration was only found to be significantly elevated in AD (127% of control levels; p=0.0095) using SELDI-TOF with IMAC30 arrays.

CONCLUSIONS

These data suggest that the measured Abeta level in CSF may differ depending on whether antibody-based methods are used or not, possibly caused by epitope masking due to Abeta oligomerization or to binding of Abeta to carrier proteins.

Identification of a novel panel of cerebrospinal fluid biomarkers for Alzheimer's disease

An early and accurate diagnosis of Alzheimer's disease (AD) is required to initiate symptomatic treatment with currently approved drugs and will be of even greater importance if disease modifying compounds in development display a clinical effect. Protein profiles of human cerebrospinal fluid samples from AD patients (n=95) and population-based healthy controls (n=72) were analyzed by SELDI-TOF-MS in order to discover and characterize novel candidate biomarker combinations that differentiate AD patients from normal aging in this explorative study. Thirty candidate biomarkers (ROC AUC>0.7) were discovered that could differentiate patients with AD from healthy controls. Protein sequence determination and positive identification of 15 biomarkers revealed potential associations between the identified markers and AD pathogenesis. A multi-marker combination of five peaks could distinguish AD from healthy control individuals with high sensitivity (97%) and specificity (98%). The panel of five markers was tested on a blinded independent data set of 30 AD samples and 28 controls giving 100% sensitivity and 97% specificity. This novel panel of biomarkers could potentially be used to improve the accuracy of diagnosis of AD.

Associations between white matter lesions, cerebrovascular risk factors, and low CSF Abeta42

OBJECTIVE

To analyze a putative relationship between white matter lesions (WMLs), risk factors for WMLs, and Alzheimer disease (AD) as measured with the surrogate marker CSF Abeta42.

METHODS

The authors analyzed effects of acquired risk factors for cerebrovascular disease and WMLs on AD as measured with an intermediate marker, CSF Abeta42. A total of 127 consecutive patients with subjective memory impairment (mean age 66 years; 57 women) investigated at a university-based memory clinic had brain MRI scans. WMLs were rated on a 12-point scale with a semiquantitative procedure. They used path analysis with established and possible risk factors for WMLs and for reduced CSF Abeta42 (age, hypertension, hyperhomocysteinemia, hypercholesterolemia, APOE-epsilon4) as variables.

RESULTS

The WML score was 1.5 points higher (p < 0.05) in hypertensive than in nonhypertensive patients and 1.9 points higher (p < 0.05) in patients with hyperhomocysteinemia than in those with normal homocysteine levels. Hypercholesterolemia increased the probability of low CSF Abeta42 levels by 0.2 (p < 0.05). For each point increase in WML score, the probability of low CSF Abeta42 levels increased by 0.03 (p < 0.05). APOE-epsilon4 was associated with reduced CSF Abeta42 (p < 0.01).

CONCLUSION

Both hypercholesterolemia and white matter lesions may contribute to low CSF Abeta42 by independent mechanisms.