Mattias Göthlin

Cognitive profiles of incipient dementia in the Goteborg MCI study.

Objective: To study which cognitive profiles of incipient dementia strongest predict the conversion to Alzheimer’s disease (AD) and mixed dementia (MD)/vascular dementia (VaD). Methods: 260 subjects with mild cognitive impairment (MCI) were included in the study and 209 (79%) were followed up after 2 years. At baseline, the subjects were assessed with a neuropsychological battery covering the cognitive domains speed/attention, memory, visuospatial, language and executive functions. Results: After 2 years, 9 subjects were considered normal, 148 had stationary MCI and 47 (23%) had converted to dementia. Twenty subjects were diagnosed with AD, 15 with MD and 9 with VaD. The others were 2 with unspecified dementias and 1 with primary progressive aphasia. Dementia converters had a high proportion of impairment in all cognitive domains. The profiles of incipient AD and MD/VaD differed, with memory, visuospatial and language symptoms preceding AD, and executive and speed/attention symptoms preceding MD/VaD. Conclusions: The risk of converting to dementia is increased when domains in addition to memory are impaired. The incipient AD and MD/VaD profiles differed quite clearly. Considering that the vascular group consisted of a majority of patients with MD, the differences are convincing – vascular disease seems to have an essential impact on cognition.

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.

B-type natriuretic peptide plasma levels are elevated in subcortical vascular dementia

High levels of B-type natriuretic peptide (BNP), a serum marker of congestive heart failure, are associated with an increased risk for cognitive decline. However, no study has yet assessed this marker in different subtypes of dementia. We tested the hypothesis that BNP has a more significant association with vascular dementia than Alzheimer disease. Plasma BNP was measured in 15 patients with subcortical vascular dementia, in 19 Alzheimer patients without evidence of vascular comorbidity, and in age-matched controls. Compared with controls (28±7 ng/l), BNP was elevated in subcortical vascular dementia (63±17 ng/l; P=0.03), but not in Alzheimer disease (36±5 ng/l). In conclusion, subcortical vascular dementia is indeed associated with moderately elevated BNP levels, whereas this could not be shown for Alzheimer disease. This probably reflects the larger cardiovascular burden in patients with subcortical vascular dementia.

The Gothenburg MCI study: Design and distribution of Alzheimer’s disease and subcortical vascular disease diagnoses from baseline to 6-year follow-up

There is a need for increased nosological knowledge to enable rational trials in Alzheimer’s disease (AD) and related disorders. The ongoing Gothenburg mild cognitive impairment (MCI) study is an attempt to conduct longitudinal in-depth phenotyping of patients with different forms and degrees of cognitive impairment using neuropsychological, neuroimaging, and neurochemical tools. Particular attention is paid to the interplay between AD and subcortical vascular disease, the latter representing a disease entity that may cause or contribute to cognitive impairment with an effect size that may be comparable to AD. Of 664 patients enrolled between 1999 and 2013, 195 were diagnosed with subjective cognitive impairment (SCI), 274 with mild cognitive impairment (MCI), and 195 with dementia, at baseline. Of the 195 (29%) patients with dementia at baseline, 81 (42%) had AD, 27 (14%) SVD, 41 (21%) mixed type dementia (=AD + SVD = MixD), and 46 (23%) other etiologies. After 6 years, 292 SCI/MCI patients were eligible for follow-up. Of these 292, 69 (24%) had converted to dementia (29 (42%) AD, 16 (23%) SVD, 15 (22%) MixD, 9 (13%) other etiologies). The study has shown that it is possible to identify not only AD but also incipient and manifest MixD/SVD in a memory clinic setting. These conditions should be taken into account in clinical trials.

Alzheimer’s disease—subcortical vascular disease spectrum in a hospital-based setting: Overview of results from the Gothenburg MCI and dementia studies

The ability to discriminate between Alzheimer’s disease (AD), subcortical vascular disease, and other cognitive disorders is crucial for diagnostic purposes and clinical trial outcomes. Patients with primarily subcortical vascular disease are unlikely to benefit from treatments targeting the AD pathogenic mechanisms and vice versa. The Gothenburg mild cognitive impairment (MCI) and dementia studies are prospective, observational, single-center cohort studies suitable for both cross-sectional and longitudinal analysis that outline the cognitive profiles and biomarker characteristics of patients with AD, subcortical vascular disease, and other cognitive disorders. The studies, the first of which started in 1987, comprise inpatients with manifest dementia and patients seeking care for cognitive disorders at an outpatient memory clinic. This article gives an overview of the major published papers (neuropsychological, imaging/physiology, and neurochemical) of the studies including the ongoing Gothenburg MCI study. The main findings suggest that subcortical vascular disease with or without dementia exhibit a characteristic neuropsychological pattern of mental slowness and executive dysfunction and neurochemical deviations typical of white matter changes and disturbed blood–brain barrier function. Our findings may contribute to better healthcare for this underrecognized group of patients. The Gothenburg MCI study has also published papers on multimodal prediction of dementia, and cognitive reserve.

Sahlgrenska Academy Self-reported Cognitive Impairment Questionnaire (SASCI-Q)--a research tool discriminating between subjectively cognitively impaired patients and healthy controls.

BACKGROUND Subjective cognitive impairment (SCI) is a potential early marker for actual cognitive decline. The cognitive manifestation of the SCI stage is, however, largely unknown. Self-report instruments developed especially for use in the SCI population are lacking, and many SCI studies have not excluded mild cognitive impairment and dementia. We developed and tested a patient-based questionnaire on everyday cognitive function aiming to discriminate between patients with subjective, but not objective, cognitive impairment and healthy controls. METHODS Individuals experiencing cognitive impairment were interviewed to generate a pool of items. After condensing to 97 items, we tested the questionnaire in 93 SCI patients seeking care at a memory clinic (age M = 64.5 years, Mini-Mental State Examination (MMSE) M = 29.0) and 50 healthy controls (age M = 69.6 years, MMSE M = 29.3). Further item reduction was conducted to maximize that remaining items would discriminate between SCI patients and controls, using a conservative α level and requiring medium to high effect sizes. Internal consistency reliability and convergent validity was subsequently examined. RESULTS Forty-five items discriminated between the groups, resulting in the Sahlgrenska Academy Self-reported Cognitive Impairment Questionnaire (SASCI-Q). Internal consistency was high and correlations to a single question on memory functioning were of medium to large sizes. Most remaining items were related to the memory domain. CONCLUSION The SASCI-Q discriminates between SCI patients and healthy controls and demonstrates satisfying psychometric properties. The instrument provides a research method for examining SCI and forms a foundation for future examining which SCI symptoms predict objective cognitive decline. The cognitive manifestation of the SCI stage is mostly related to experiences of memory deficits.

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.

Subjective Cognitive Impairment Is a Predominantly Benign Condition in Memory Clinic Patients Followed for 6 Years: The Gothenburg-Oslo MCI Study

Background/Aims: In the quest for prevention or treatment, there is a need to find early markers for preclinical dementia. This study observed memory clinic patients with subjective cognitive impairment (SCI) and normal cognitive function at baseline. The primary aim was to address SCI as a potential risk factor for cognitive decline. The secondary aim was to address a potential relation between (1) baseline cerebrospinal fluid biomarkers and (2) a decline in memory performance over the first 2 years of follow-up, with a possible cognitive decline after 6 years. Methods: Eighty-one patients (mean age 61 years) were recruited from university memory clinics and followed up for 6 years. Results: Eighty-six percent of the cohort remained cognitively stable or improved, 9% developed mild cognitive impairment, and only 5% (n = 4) developed dementia. Regression analysis revealed that low levels of Aβ42 at baseline and memory decline during the first 2 years predicted dementia. When combined, these variables were associated with a 50% risk of developing dementia. Conclusions: Cognitive stability for 86% of the cohort suggests that SCI is predominantly a benign condition with regard to neuropathology. The low number of individuals who developed dementia limits the generalizability of the results and discussion of progression factors.


T-Tau is Associated with Objective Memory Decline Over Two Years in Persons Seeking Help for Subjective Cognitive Decline: A Report from the Gothenburg-Oslo MCI Study

BACKGROUND There is a need to find very early markers for pre-clinical Alzheimers disease as interventions early in the disease process are thought to be most effective. OBJECTIVE The present study aimed to address the potential relation between cerebrospinal fluid (CSF) biomarkers and reduced cognitive function in a relatively young cohort of memory clinic patients with subjective cognitive decline. METHODS 122 patients (mean age 63 years) with subjective cognitive decline were recruited from two university memory clinics and followed for two years. RESULTS The main finding was that the subgroup with objective memory decline during the study period had significantly higher T-tau at baseline than the group with improved memory. Baseline CSF variables showed a trend toward more pathological values in the patients with memory decline compared to those who improved or remained stable. The baseline memory score of those who declined was significantly better than the baseline score of those who improved over two years. The general trend for the whole group was improved memory and executive test scores. There were no differences in cognitive scores based on CSF quartiles at baseline, nor were there differences in cognitive outcome for patients with early amnestic mild cognitive impairment versus average cognitive function at baseline. CONCLUSIONS The main finding that T-tau rather than amyloid-β was associated with memory decline do not support the prevailing opinion about the chain of events assumed to take place in Alzheimers disease. In addition, memory decline was not associated with poor baseline memory score. Thus, a memory cut-off indicating low baseline memory would not would have identified the declining group.

Vascular disease, Alzheimer's disease biomarkers and cognition in mild cognitive impairment: additive or synergetic effects?

Background/Aims: To study how vascular disease and Alzheimer-typical biomarkers relate to cognitive performance in mild cognitive impairment (MCI). Methods: Three groups diagnosed with MCI, one with vascular disease (MCI-vas, n = 61), one with Alzheimer-typical biomarkers (MCI-bio, n = 99) and one with both vascular disease and Alzheimer-typical biomarkers (MCI-vasbio, n = 56), were examined with a comprehensive neuropsychological test battery. Results: The MCI-vas and MCI-bio groups performed quite similarly on the test battery, whereas the MCI-vasbio group tended to perform worse than the other groups. MCI-vasbio patients performed significantly worse on tests within all cognitive domains, with the most clear-cut differences on an executive test. Conclusions: Considering the small differences between MCI-vas and MCI-bio, vascular disease or biomarkers alone do not seem to be associated with a specific cognitive profile. The combination of vascular disease and Alzheimer-typical biomarkers, on the other hand, seems to be associated with more severe cognitive deficits. The difference in an aspect of executive functioning is interpreted as a synergetic effect.