Serum phosphate and cognitive function in older men

Objective

Determine whether serum phosphate is associated with concurrent cognitive impairment and subsequent cognitive decline in older men independent of demographic covariates and atherosclerotic risk factors.

Methods

In a prospective study of 5529 men enrolled in the Osteoporotic Fractures in Men study, we measured baseline serum phosphate, baseline cognitive function, and change in cognitive function between baseline and follow‐up exams an average of 4.6 years later using the Modified Mini‐Mental State (3MS) Examination and Trails B.

Results

There was no association between serum phosphate and odds of cognitive impairment as assessed by baseline 3MS score or risk of cognitive decline as assessed by longitudinal change in 3MS score. Higher baseline serum phosphate was associated with higher odds of poor executive function as assessed by Trails B with fully adjusted odds ratios 1.12 (95% confidence interval: 0.83–1.52), 1.31 (0.97–1.77), and 1.45 (1.08–1.94) for men in the second, third, and fourth versus the bottom quartile (referent group) of serum phosphate (p‐trend 0.007). However, higher phosphate level was not associated with risk of decline in executive function as assessed by longitudinal change in Trails B score with fully adjusted odds ratios 0.94 (95% confidence interval 0.69–1.28), 0.96 (0.70–1.32), and 1.21 (0.89–1.66) for men in the second, third, and fourth versus the bottom quartile (referent group) of serum phosphate (p‐trend 0.22).

Conclusions

Higher serum phosphate in older men was associated with a higher likelihood of poor executive function, but not with impaired global cognitive function or decline in executive or global cognition. Copyright © 2017 John Wiley & Sons, Ltd.     

Cognitive function in primary and secondary progressive multiple sclerosis: A multiparametric magnetic resonance imaging study

Background and purpose

The differences in cognitive function between primary progressive and secondary progressive multiple sclerosis (MS) remain unclear. We compared cognitive performance between primary progressive multiple sclerosis (PPMS) and secondary progressive multiple sclerosis (SPMS), and explored the structural and functional magnetic resonance imaging (MRI) correlates of their cognitive functions.

Methods

Seventy-five healthy controls and 183 MS patients (60 PPMS and 123 SPMS) underwent 3.0-T MRI. MS patients were administered the Brief Repeatable Battery of Neuropsychological Tests; cognitive domain z-scores were calculated and then averaged to obtain a measure of global cognition. Using hierarchical linear regression analysis, the contribution of lesion volumes, normalized brain volumes, white matter (WM) fractional anisotropy (FA) and mean diffusivity abnormalities, and resting state (RS) functional connectivity (FC) alterations to global cognition in PPMS and SPMS was investigated.

Results

PPMS and SPMS had similar z-scores in all investigated cognitive domains. Poor global cognitive function was associated with decreased FA of the medial lemniscus (ΔR ² = 0.11, p = 0.011) and lower normalized gray matter volume (ΔR ² = 0.29, p < 0.001) in PPMS, and with decreased FA of the fornix (ΔR ² = 0.35, p < 0.001) and lower normalized WM volume (ΔR ² = 0.05; p = 0.034) in SPMS.

Conclusions

PPMS and SPMS had similar neuropsychological performance. Cognitive dysfunction in PPMS and SPMS was related to distinct patterns of structural MRI abnormalities and involvement of different WM tracts, whereas RS FC alterations did not contribute to explaining their global cognitive functioning.     

Relationships between socio‐clinico‐demographic factors and global cognitive function in the oldest old living in the Tokyo Metropolitan area: Reanalysis of the Tokyo Oldest Old Survey on Total Health (TOOTH)

Background

Despite a steady increase in life expectancy, a few studies have investigated cross‐sectional correlates and longitudinal predictors of cognitive function, a core domain of the successful aging, among socio‐clinico‐demographic factors in the oldest‐old exclusively.

Objectives

The aims of this study were to examine socio‐clinico‐demographic characteristics associated with global cognition and its changes in the oldest‐old.

Methods

We reanalyzed a dataset of cognitively preserved community‐dwelling subjects aged 85 years and older in the Tokyo Oldest Old Survey on Total Health, a 6‐year longitudinal observational study. This study consisted of (1) baseline cross‐sectional analyses examining correlates of global cognition (n = 248) among socio‐clinico‐demographic factors and (2) longitudinal analyses examining baseline predictors for changes of global cognition in 3‐year follow‐up (n = 195). The Mini‐Mental State Examination was used as a screening test to assess global cognition.

Results

At baseline, higher weights were related to higher cognitive function in the oldest‐old. The baseline predictors of global cognitive decline in 3‐year follow‐up were higher global cognition, shorter education period, and lower sociocultural activities and lower instrumental activity of daily living, in this order.

Conclusions

The present study suggests that it is crucial to attain higher education during early life and avoid leanness or obesity, participate in sociocultural cognitive activities during late life, and maintain instrumental activity of daily living to preserve optimal cognitive function in the oldest‐old, which will facilitate developing prevention strategies for cognitive decline and promoting successful aging in this increasing population.     

Longitudinal changes in global and domain specific cognitive function in the very‐old: findings from the Newcastle 85+ Study

Objective

Ageing is associated with changes in cognition in some, but not all domains. In young–old adults, defined as persons aged 65–84 years, baseline cognitive function has been shown to impact on cognitive trajectories. Whether similar patterns occur in the very‐old, defined as persons aged 85 years and over, is not known.

Methods

Longitudinal changes (5 years' follow‐up) in global and domain specific cognitive function including memory, attention and speed were investigated in participants from the Newcastle 85+ Study (n = 845). At baseline, participants were grouped using Mini‐Mental State Examination cut‐off scores and dementia status into the following: not impaired, mildly impaired or severely impaired/dementia groups.

Results

Only a limited number of cognitive measures showed significant decline in performance over time. Where observed, change generally occurred only in the severely impaired group. In the severely impaired group, small differences in baseline age were associated with poorer performance over time on most measures. Education was not protective against cognitive decline in any group.

Conclusions

There are individuals who maintain a high level of cognitive function or only show mild impairments even into their ninth decade of life. This group of successful cognitive agers may provide insight for identifying predictors of cognitive integrity in later life. In individuals with severe impairment, cognitive performance shows significant decline over time, especially in measures of attention and speed. Further work to identify those individuals at highest risk of cognitive decline is necessary to implement early support and intervention strategies in this rapidly expanding age group. © 2017 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons Ltd.     

Physical activity and brain health in patients with atrial fibrillation

Background and purpose

Vascular brain lesions, such as ischemic infarcts, are common among patients with atrial fibrillation (AF) and are associated with impaired cognitive function. The role of physical activity (PA) in the prevalence of brain lesions and cognition in AF has not been investigated.

Methods

Patients from the multicenter Swiss-AF cohort study were included in this cross-sectional analysis. We assessed regular exercise (RE; at least once weekly) and minutes of weekly PA using a validated questionnaire. We studied associations with ischemic infarcts, white matter hyperintensities, cerebral microbleeds, and brain volume on brain magnetic resonance imaging and with global cognition measured with a cognitive construct (CoCo) score.

Results

Among 1490 participants (mean age = 72 ± 9 years), 730 (49%) engaged in RE. In adjusted regression analyses, RE was associated with a lower prevalence of ischemic infarcts (odds ratio [OR] = 0.78, 95% confidence interval [CI] = 0.63–0.98, p = 0.03) and of moderate to severe white matter hyperintensities (OR = 0.78, 95% CI = 0.62–0.99, p = 0.04), higher brain volume (β-coefficient = 10.73, 95% CI = 2.37–19.09, p = 0.01), and higher CoCo score (β-coefficient = 0.08, 95% CI = 0.03–0.12, p < 0.001). Increasing weekly PA was associated with higher brain volume (β-coefficient = 1.40, 95% CI = 0.65–2.15, p < 0.001).

Conclusions

In AF patients, RE was associated with a lower prevalence of ischemic infarcts and of moderate to severe white matter disease, with larger brain volume, and with better cognitive performance. Prospective studies are needed to investigate whether these associations are causal. Until then, our findings suggest that patients with AF should be encouraged to remain physically active.     

Longitudinal cognitive changes in patients with early Parkinson's disease and neuropsychiatric symptoms

Aims

In this study, we aimed to investigate the effect of neuropsychiatric symptoms (NPS) on the rate of cognitive decline for both global cognition and specific cognitive domains in a cohort of patients from the Parkinson's Progression Markers Initiative (PPMI).

Method

Prospectively longitudinal data were obtained from the PPMI cohort. NPS, including depression, anxiety, apathy, psychosis, impulse control disorders (ICDs), and cognition ability, were evaluated by a series of questionnaires. Linear mixed-effects models were used to investigate the relationship between NPS and the rate of cognitive decline. Generalized estimating equations (GEEs) were used to investigate the relationship between NPS and the occurrence of mild cognitive impairment (MCI).

Results

In total, 423 patients with Parkinson's disease (PD) were recruited at baseline and 395, 378, 366, 346, and 315 participants were followed up at 1, 2, 3, 4, and 5 years, respectively. Depression, anxiety, apathy, and psychosis were associated with global cognitive decline. Except for those with ICDs, patients with psychosis, depression, anxiety, and apathy were more likely to meet the criteria for MCI. Patients with depression and anxiety showed a progressive decline in four major cognitive domains. Apathy and ICDs were separately associated with a progressive decline in processing speed-attention and memory, respectively.

Conclusions

Neuropsychiatric symptoms, including psychosis, depression, anxiety, and apathy, could be used to predict future cognitive decline in patients with PD.     

Circadian rest-activity rhythm and longitudinal brain changes underlying late-life cognitive decline

Aim

The neurobiological substrates underlying the relationship of circadian rest-activity rhythm (RAR) alteration with accelerated late-life cognitive decline are not clearly understood. In the present study, the longitudinal relationship of objectively measured circadian RAR with in vivo Alzheimer disease (AD) pathologies and cerebrovascular injury was investigated in older adults without dementia.

Methods

The present study included 129 participants without dementia who participated in the KBASE (Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer's Disease) cohort. All participants underwent actigraphy at baseline and two consecutive [¹¹C] Pittsburgh compound-B positron emission tomography (PET), [¹⁸F] fluorodeoxyglucose-PET, magnetic resonance imaging, and Mini-Mental State Examination (MMSE) at baseline and at a 2-year follow-up assessment. The associations of circadian RAR with annualized change in neuroimaging measures including global amyloid-beta retention, AD-signature region cerebral glucose metabolism (AD-CM), and white matter hyperintensity volume were examined.

Results

Delayed acrophase at baseline was significantly associated with greater annualized decline of AD-CM over a 2-year period, but not with that of other neuroimaging measures. In contrast, other circadian RAR parameters at baseline had no association with annualized change of any neuroimaging measures. Annualized decline of AD-CM was also significantly positively associated with the annual change in MMSE scores. Furthermore, a mediation analysis showed that greater reduction in AD-CM mediated the effect of delayed acrophase at baseline on faster decline of MMSE score.

Conclusion

The findings indicate that delayed acrophase in late life may cause or predict hypometabolism at AD-signature brain regions, which underlies cognitive decline in the near future.     

Longitudinal diffusion tensor imaging changes in early Parkinson’s disease: ICICLE-PD study

Objective

To investigate whether white matter microstructural changes can be used as a predictor of worsening of motor features or cognitive decline in patients with Parkinson’s disease and verify whether white matter microstructural longitudinal changes differ between patients with Parkinson’s disease with normal cognition and those with mild cognitive impairment.

Methods

We enrolled 120 newly diagnosed patients with early stage Parkinson’s disease (27 with mild cognitive impairment and 93 with normal cognition) along with 48 controls. Participants were part of the incidence of cognitive impairment in cohorts with longitudinal evaluation in Parkinson’s disease study and were assessed at baseline and 18 months later with cognitive, motor tests and diffusion tensor imaging. The relationships between fractional anisotropy and mean diffusivity with disease status, cognitive and motor function were investigated.

Results

At baseline, patients with early stage Parkinson’s disease had significantly higher widespread mean diffusivity relative to controls, regardless of cognitive status. In patients with Parkinson’s disease/mild cognitive impairment, higher mean diffusivity was significantly correlated with lower attention and executive function scores. At follow-up frontal mean diffusivity increased significantly when comparing patients with Parkinson’s disease/mild cognitive impairment with those with normal cognition. Baseline mean diffusivity was a significant predictor of worsening of motor features in Parkinson’s disease.

Conclusions

Mean diffusivity represents an important correlate of cognitive function and predictor of motor impairment in Parkinson’s disease: DTI is potentially a useful tool in stratification of patients into clinical trials and to monitor the impact of treatment on motor function.

     

Brain morphology links systemic inflammation to cognitive function in midlife adults

Background: Inflammation is linked to cognitive decline in midlife, but the neural basis for this link is unclear. One possibility is that inflammation associates with adverse changes in brain morphology, which accelerates cognitive aging and later dementia risk. Clear evidence is lacking, however, regarding whether inflammation relates to cognition in midlife via changes in brain morphology. Accordingly, the current study examines whether associations of inflammation with cognitive function are mediated by variation in cortical gray matter volume among midlife adults. Methods: Plasma levels of interleukin (IL)-6 and C-reactive protein (CRP), relatively stable markers of peripheral systemic inflammation, were assessed in 408 community volunteers aged 30–54 years. All participants underwent structural neuroimaging to assess global and regional brain morphology and completed neuropsychological tests sensitive to early changes in cognitive function. Measurements of brain morphology (regional tissue volumes and cortical thickness and surface area) were derived using Freesurfer. Results: Higher peripheral inflammation was associated with poorer spatial reasoning, short term memory, verbal proficiency, learning and memory, and executive function, as well as lower cortical gray and white matter volumes, hippocampal volume and cortical surface area. Mediation models with age, sex and intracranial volume as covariates showed cortical gray matter volume to partially mediate the association of inflammation with cognitive performance. Exploratory analyses of body mass suggested that adiposity may be a source of the inflammation linking brain morphology to cognition. Conclusions: Inflammation and adiposity might relate to cognitive decline via influences on brain morphology.     

Multiple sclerosis as a model to investigate SARS-CoV-2 effect on brain atrophy

Introduction

Data on structural brain changes after infection with SARS-CoV-2 is sparse. We postulate multiple sclerosis as a model to study the effects of SARS-CoV-2 on brain atrophy due to the unique availability of longitudinal imaging data in this patient group, enabling assessment of intraindividual brain atrophy rates.

Methods

Global and regional cortical gray matter volumes were derived from structural MRIs using FreeSurfer. A linear model was fitted to the measures of the matching pre-SARS-CoV-2 images with age as an explanatory variable. The residuals were used to determine whether the post-SARS-CoV-2 volumes differed significantly from the baseline.

Results

Fourteen RRMS patients with a total of 113 longitudinal magnetic resonance images were retrospectively analyzed. We found no acceleration of brain atrophy after infection with SARS-CoV-2 for global gray matter volume (p = 0.17). However, on the regional level, parahippocampal gyri showed a tendency toward volume reduction (p = 0.0076), suggesting accelerated atrophy during or after infection.

Conclusions

Our results illustrate the opportunity of using longitudinal MRIs from existing MS registries to study brain changes associated with SARS-CoV-2 infections. We would like to address the global MS community with a call for action to use the available cohorts, reproduce the proposed analysis, and pool the results.     

Brain function and structure and risk for incident diabetes: The Atherosclerosis Risk in Communities Study

Introduction

Diabetes is prospectively associated with cognitive decline. Whether lower cognitive function and worse brain structure are prospectively associated with incident diabetes is unclear.

Brain Structure in Neuropsychologically Defined Subgroups of Schizophrenia and Psychotic Bipolar Disorder

Background:

Neuropsychological impairment is heterogeneous in psychosis. The association of intracranial volume (ICV) and total brain volume (TBV) with cognition suggests brain structure abnormalities in psychosis will covary with the severity of cognitive impairment. We tested the following hypotheses: (1) brain structure abnormalities will be more extensive in neuropsychologically impaired psychosis patients; (2) psychosis patients with premorbid cognitive limitations will show evidence of hypoplasia (ie, smaller ICV); and (3) psychosis patients with evidence of cognitive decline will demonstrate atrophy (ie, smaller TBV, but normal ICV).

Methods:

One hundred thirty-one individuals with psychosis and 97 healthy subjects underwent structural magnetic resonance imaging and neuropsychological testing. Patients were divided into neuropsychologically normal and impaired groups. Impaired patients were further subdivided into deteriorated and compromised groups if estimated premorbid intellect was average or below average, respectively. ICV and TBV were compared across groups. Localized brain volumes were qualitatively examined using voxel-based morphometry.

Results:

Compared to healthy subjects, neuropsychologically impaired patients exhibited smaller TBV, reduced grey matter volume in frontal, temporal, and subcortical brain regions, and widespread white matter volume loss. Neuropsychologically compromised patients had smaller ICV relative to healthy subjects, and neuropsychologically normal and deteriorated patient groups, but relatively normal TBV. Deteriorated patients exhibited smaller TBV compared to healthy subjects, but relatively normal ICV. Unexpectedly, TBV, adjusted for ICV, was reduced in neuropsychologically normal patients.

Conclusions:

Patients with long-standing cognitive limitations exhibit evidence of early cerebral hypoplasia, whereas neuropsychologically normal and deteriorated patients show evidence of brain tissue loss consistent with progression or later cerebral dysmaturation.Key words: psychosis, cognition, brain volume, neurodevelopmental, neuroprogressive     

Multi-networks connectivity at baseline predicts the clinical efficacy of left angular gyrus-navigated rTMS in the spectrum of Alzheimer's disease: A sham-controlled study

Introduction

Neuro-navigated repetitive transcranial magnetic stimulation (rTMS) is effective in alleviating cognitive deficits in Alzheimer's disease (AD). However, the strategy for target determination and the mechanisms for cognitive improvement remain unclear.

Methods

One hundred and thirteen elderly subjects were recruited in this study, including both cross-sectional (n = 79) and longitudinal experiments (the rTMS group: n = 24; the sham group: n = 10). The cross-sectional experiment explored the precise intervention target based on the cortical–hippocampal network. The longitudinal experiment investigated the clinical efficacy of neuro-navigated rTMS treatment over a four-week period and explored its underlying neural mechanism using seed-based and network-based analysis. Finally, we applied connectome-based predictive modeling to predict the rTMS response using these functional features at baseline.

Results

RTMS at a targeted site of the left angular gyrus (MNI: −45, −67, 38) significantly induced cognitive improvement in memory and language function (p < 0.001). The improved cognition correlated with the default mode network (DMN) subsystems. Furthermore, the connectivity patterns of DMN subsystems (r = 0.52, p = 0.01) or large-scale networks (r = 0.85, p = 0.001) at baseline significantly predicted the Δ language cognition after the rTMS treatment. The connectivity patterns of DMN subsystems (r = 0.47, p = 0.019) or large-scale networks (r = 0.80, p = 0.001) at baseline could predict the Δ memory cognition after the rTMS treatment.

Conclusion

These findings suggest that neuro-navigated rTMS targeting the left angular gyrus could improve cognitive function in AD patients. Importantly, dynamic regulation of the intra- and inter-DMN at baseline may represent a potential predictor for favorable rTMS treatment response in patients with cognitive impairment.     

Associations of childhood socioeconomic status with mid‐life and late‐life cognition in Chinese middle‐aged and older population based on a 5‐year period cohort study

Objectives

A prospective study was performed to examine the relationship of childhood socioeconomic status (SES) with cognition and the rate of change in a nationally representative sample of community‐dwelling middle‐aged and older Chinese population.

Methods

This study mainly focused on 3 composite measures of cognitive function, including Telephone Interview of Cognitive Status, word recall, and drawing a figure successfully. Childhood SES was evaluated by parental occupation and education, childhood residence, and self‐evaluated financial status. We designed an analysis strategy adding predictors incrementally in different models to examine the changes of effects of childhood SES on cognition by latent growth curve models.

Results

Finally, a total of 10 533 respondents were prospectively studied, including 5980 respondents aged 45–59 and 4553 aged 60–90. Cognition in younger cohort showed a curvilinear change, while cognition in older cohort showed a linear decline. After controlling for covariates, middle‐aged respondents with higher self‐evaluated financial status (β : ?0.22, P < .001), better health status (β : ?0.13, P < .001), higher parental education (β : 0.17 and 0.10, P < .001), who had lived in city/town before 16 years (β : 0.69, P < .001), and whose fathers engaged in nonfarming work (β : 0.43, P < .001) were associated with the better baseline cognition. Similar results were found in older cohort. Additionally, early‐life SES was not associated with cognitive decline in both cohorts.

Conclusions

This study indicates that childhood SES is associated with mid‐life and late‐life baseline cognition, but it is not contributed to cognition decline. Interventions in early‐life focused on improving childhood SES might have positive impacts on baseline cognition in later‐life.

     

Perioperative Serum Brain Natriuretic Peptide and Cardiac Troponin in Elective Intracranial Surgery

Background

There are some intracranial insults which are associated with cardiac abnormalities. Studies of these abnormalities have never been carried out in elective intracranial neurosurgery for the removal of brain tumors. Our prospective study aims at quantifying serum cardiac troponin T (cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) before and after elective intracranial neurosurgery for tumor resection in patients with no history of cardiac abnormality.

Methods

Pre- and postoperative serum cTnT and NT-proBNP were measured in 108 patients submitted to elective major intracranial surgery for the removal of neoplastic lesions. We tested potentially predictive models for these biomarker serum levels.

Results

cTnT was undetectable both before and after surgery. Median (IQR) basal NT-proBNP was 35 (18?C69)?pg/mL and 110 (51?C191)?pg/mL after surgery. In a multiple linear regression model, basal NT-proBNP was predicted by age, gender, BMI, and the presence of ??mass effect?? (midline shift or effaced perimesencephalic cisterns on preoperative CT scan) (whole model P?<?0.0001; R ²?=?0.3502; and Adjusted R ²?=?0.3247). Postoperative NT-proBNP increase was predicted by baseline NT-proBNP level (whole model P?<?0.0001; R ²?=?0.5106; and Adjusted R ²?=?0.5052).

Conclusion

An intracranial mass effect is associated with higher NT-proBNP serum levels in patients with a brain neoplasm. Following elective intracranial surgery for brain tumor resection NT-proBNP values increase.     

Statins and cognition in late‐life bipolar disorder

Objectives

Recent data suggests that statins have positive effects on cognition in older adults. Studies in patients with mood disorders have found contradicting positive and negative effects of statins on mood and cognition, with limited data in bipolar disorder (BD). The objective of this study was to assess the association between statin use and cognition in older adults with BD.

Methods

In a cross‐sectional sample of 143 euthymic older adults with BD (age ≥ 50), statin users (n = 48) and nonusers (n = 95) were compared for cognitive outcomes: Global and cognitive domain z‐scores were calculated from detailed neuropsychological batteries using normative data from healthy comparators (n = 87).

Results

The sample had a mean age of 64.3 (±8.9) years, 65.0% were female, with an average of 15.1 (±2.79) years of education. Statin users did not differ from nonusers on global (?0.60 [±0.69] vs ?0.49 [±0.68], t[127] = 0.80, P = .42) or individual cognitive domains z‐score.

Conclusions

In older patients with BD, statin use is not independently associated with cognitive impairment. This suggests that in older BD patients, the cognitive dysfunction associated with BD trumps the potential cognitive benefit that is associated with statins in older adults without a psychiatric disorder. Further, statins do not seem to exacerbate this cognitive dysfunction. Future longitudinal studies are needed to confirm these findings.     

Factors associated with brain volume in major depression in older adults without dementia: results from a large autopsy study

Objective

We examined brain volume and atrophy in individuals with major depressive disorder (MDD) without dementia that were referred to a large autopsy service. We also examined potential risk factors for brain atrophy, including demographics and clinical variables.

Methods

In this study, 1373 participants (787 male) aged 50 years or older who died from natural causes were included. Participants with no reliable informant, with cognitive impairment or dementia, with a medical history of severe chronic disease, or with prolonged agonal state were excluded. Presence of MDD at least once in their lifetime was defined according to the Structured Clinical Interview for DSM. Brain volume was measured immediately after removal from the skull.

Results

Mean age at death was 68.6 ± 11.6, and MDD was present in 185 (14%) individuals. Smaller brain volume was associated with older age (p < 0.001), lower education (years; p < 0.001), hypertension (p = 0.001), diabetes (p = 0.006), and female gender (p < 0.001). In the multivariate analysis adjusted for sociodemographics and cardiovascular risk factors, smaller brain volume was not associated with major depression (β = ?0.86, 95% CI = ?26.50 to 24.77, p = 0.95).

Conclusions

In this large autopsy study of older adults, MDD was not associated with smaller brain volumes. Regardless of the presence of MDD, in this sample of older adults without dementia, we found that smaller brain volumes were associated with risk factors for brain neurodegeneration such as older age, diabetes, hypertension, and lower education. Copyright © 2017 John Wiley & Sons, Ltd.     

Progression from normal cognition to mild cognitive impairment in a diverse clinic-based and community-based elderly cohort

Introduction

Investigation of the conversion rates from normal cognition (NC) to mild cognitive impairment (MCI) is important, as effective early intervention could potentially prevent or substantially delay the onset of dementia. However, reported conversion rates differ across studies and recruitment source. Our study examined predictors of conversion from NC to MCI in a racially and ethnically diverse sample drawn both from community and clinic recruitment sources.

Adolescents with prenatal cocaine exposure show subtle alterations in striatal surface morphology and frontal cortical volumes

Background

Published structural neuroimaging studies of prenatal cocaine exposure (PCE) in humans have yielded somewhat inconsistent results, with several studies reporting no significant differences in brain structure between exposed subjects and controls. Here, we sought to clarify some of these discrepancies by applying methodologies that allow for the detection of subtle alterations in brain structure.

Methods

We applied surface-based anatomical modeling methods to magnetic resonance imaging (MRI) data to examine regional changes in the shape and volume of the caudate and putamen in adolescents with prenatal cocaine exposure (n = 40, including 28 exposed participants and 12 unexposed controls, age range 14 to 16 years). We also sought to determine whether changes in regional brain volumes in frontal and subcortical regions occurred in adolescents with PCE compared to control participants.

Results

The overall volumes of the caudate and putamen did not significantly differ between PCE participants and controls. However, we found significant (P <0.05, uncorrected) effects of levels of prenatal exposure to cocaine on regional patterns of striatal morphology. Higher levels of prenatal cocaine exposure were associated with expansion of certain striatal subregions and with contraction in others. Volumetric analyses revealed no significant changes in the volume of any subcortical region of interest, but there were subtle group differences in the volumes of some frontal cortical regions, in particular reduced volumes of caudal middle frontal cortices and left lateral orbitofrontal cortex in exposed participants compared to controls.

Conclusions

Prenatal cocaine exposure may lead to subtle and regionally specific patterns of regional dysmorphology in the striatum and volumetric changes in the frontal lobes. The localized and bidirectional nature of effects may explain in part the contradictions in the existing literature.     

MRI measures and progression of cognitive decline in nondemented elderly attending a memory clinic

OBJECTIVE: To investigate whether MRI-based volumes of whole brain, medial temporal lobe and white matter hyperintensities (WMH) predict progression of cognitive decline in a sample of nondemented elderly. METHODS: Thirty-seven nondemented elderly attending a memory clinic and 28 elderly controls participated in this follow-up study. The average follow-up period was 1.8 years. Cognitive function was measured at baseline and follow-up with the Cambridge Cognitive Examination (CAMCOG). Baseline Magnetic Resonance Imaging (MRI) provided quantitative measures of whole brain, medial temporal lobe and WMH. Linear mixed models controlled for age and sex were used to assess the independent associations between MRI measures, baseline cognition, and annual decline in cognition. RESULTS: Medial temporal lobe volume was independently associated with baseline CAMCOG score (p < 0.01), whereas whole brain volume (p < 0.01) and WMH (p < 0.05) were associated with annual decline in CAMCOG score. CONCLUSIONS: These data suggest that regional damage to the medial temporal lobes underlies initial mild cognitive impairment, whereas more global brain changes, such as whole brain atrophy and WMH, contribute to further progression of cognitive decline.