Structural MRI correlates of apathy symptoms in older persons without dementia: AGES-Reykjavik Study

Clinical Predictors of Cognitive Impairment in a Cohort of Patients with Older Age Bipolar Disorder

Background: An increased risk of cognitive decline has been reported in patients with older age bipolar disorder (OABD); however, the underlying factors contributing to this association remain unclear. This cross-sectional study aims to identify the clinical features associated with cognitive impairment in OABD. Methods: A total of 152 participants, aged at least 50 years and diagnosed with bipolar disorder (BD) and related disorders in agreement with the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision criteria, were included in the study and divided into two subgroups based on the presence/absence of cognitive impairment, defined as a diagnosis of Mild Neurocognitive Disorder or Major Neurocognitive Disorder. Univariate comparisons and multivariate logistic regression models were performed to investigate the associations between clinical variables and cognitive impairment. Results: Cognitively impaired patients had a higher prevalence of otherwise specified BD/cyclothymic disorder, while BD type 2 was more common in the cognitively unimpaired group. Additionally, the cognitively impaired group had a later onset of major mood episodes (p < 0.05), fewer lifetime depressive episodes (p = 0.006), a higher prevalence of vascular leukoencephalopathy (p = 0.022) and dyslipidemia (p = 0.043), a lower prevalence of agoraphobia (p = 0.040), worse global functioning (p < 0.001), and higher psychopathology severity (p < 0.001). Late onset, vascular leukoencephalopathy, and dyslipidemia were all independently associated with cognitive impairment. Conclusions: Atypical BD, late onset of mood episodes, and somatic comorbidities like vascular leukoencephalopathy and dyslipidemia are associated with a higher risk of developing cognitive impairment and neurodegenerative disorders in OABD patients.

Relationship between apathy/post-stroke depression and gait training in patients with stroke

BACKGROUND

We examined the effect of gait training on apathy/post-stroke depression (PSD) in patients with walking disorders after stroke, and the effect of apathy/PSD on gait reacquisition in subacute stroke.

METHODS

Fifty-five participants with gait disorders after stroke underwent gait training for 6 weeks. Outcome measurements included Apathy Scale (AS), Center for Epidemiologic Studies Depression Scale (CES-D), Mini-Mental State Examination, Lower Extremity Function of Stroke Impairment Assessment Set, and Functional Independence Measure-TRANSFER and -WALK scores. These scores of the participants were divided into groups with or without apathy based on AS scores for statistical analysis.

RESULTS

Both groups showed significant differences in all outcomes after gait training. In addition, even if the participants had apathy at baseline, there were no significant differences in outcomes other than AS/CES-D between the two groups after gait training. Logistic regression analysis showed that only Mini-Mental State Examination and Lower Extremity Function of Stroke Impairment Assessment Set scores affected the reacquisition of independent walking (odds ratio: 1.332, P = 0.015; odds ratio: 1.364, P = 0.005, respectively). AS and CES-D scores had no effects on gait reacquisition.

CONCLUSION

Gait training may be beneficial for both physical impairment and psychiatric symptoms in patients with stroke and may prevent poor functional recovery caused by apathy and PSD. As opposed to previous studies that have shown a negative impact of apathy and PSD on functional recovery, our results suggest that apathy/PSD may not negatively affect functional recovery when gait training is conducted in subacute stroke.

Frequency-dependent changes in the amplitude of low-frequency fluctuations in post stroke apathy: a resting-state fMRI study

Background

Apathy is a prevalent psychiatric condition after stroke, affecting approximately 30% of stroke survivors. It is associated with slower recovery and an increased risk of depression. Understanding the pathophysiological mechanisms of post stroke apathy (PSA) is crucial for developing targeted rehabilitation strategies.

Methods

In this study, we recruited a total of 18 PSA patients, 18 post-stroke non-apathy (NPSA) patients, and 18 healthy controls (HCs). Apathy was measured using the Apathy Evaluation Scale (AES). Resting-state functional magnetic resonance imaging (rs-fMRI) was utilized to investigate spontaneous brain activity. We estimated the amplitude of low-frequency fluctuation (ALFF) across three different frequency bands (typical band: 0.01-0.08 Hz; slow-4: 0.027-0.073 Hz; slow-5: 0.01-0.027 Hz) and the fractional amplitude of low-frequency fluctuation (fALFF).

Results

Band-specific ALFF differences among the three groups were analyzed. Significant differences were found in the typical band within the left lingual gyrus, right fusiform gyrus, right superior temporal gyrus (STG), and left insula. In the slow-4 band, significant differences were observed in the left middle frontal gyrus (MFG) and right STG. In the slow-5 band, significant differences were identified in the left calcarine cortex and right insula. For fALFF values, significant differences were found in the left lingual gyrus and right thalamus. Moreover, positive correlations were observed between AES scores and the ALFF values in the right STG (r = 0.490, p = 0.002) in the typical band, left MFG (r = 0.478, p = 0.003) and right STG (r = 0.451, p = 0.006) in the slow-4 band, and fALFF values of the right thalamus (r = 0.614, p < 0.001).

Conclusion

This study is the first to investigate the neural correlates of PSA using voxel-level analysis and different ALFF banding methods. Our findings indicate that PSA involves cortical and subcortical areas, including the left MFG, right STG, and right thalamus. These results may help elucidate the neural mechanisms underlying PSA and could serve as potential neuroimaging indicators for early diagnosis and intervention.

Associations of neurocognitive and neuropsychiatric patterns with brain structural biomarkers and dementia risk: A latent class analysis

BACKGROUND

Neurocognitive and neuropsychiatric symptoms are essential clinical manifestations of age-related cognitive impairment, yet their patterns of co-existence remain unclear through the cognitive continuum.

OBJECTIVE

To examine the associations of person-centered cluster-derived patterns, based on a comprehensive collection of domain-specific cognitive and neuropsychiatric assessments, with neuroimaging markers and dementia risk.

METHODS

641 participants were included in the analysis from memory clinics in Singapore. Latent class analysis was applied to define clusters of individuals with different clinical patterns. The associations between identified clinical groups with neuroimaging markers of cerebrovascular diseases and neurodegeneration were analyzed using logistic regression models. Cox proportional hazard models were applied for incident dementia.

RESULTS

Three latent classes differing in neurocognitive and neuropsychiatric impairment were identified (Class 1 "memory impairment only"; Class 2 "global cognitive impairment"; Class 3 "global cognitive and neuropsychiatric impairment"). Compared with Class 1, Class 2 and 3 were associated with smaller brain volumes, moderate-to-severe cortical atrophy and medial temporal lobe atrophy, and the presence of all cerebrovascular lesions. Moreover, compared with Class 2, Class 3 had smaller brain volumes, moderate-to-severe cortical atrophy and presence of intracranial stenosis. Additionally, compared to Class 1, Class 2 (hazard ratio [HR] = 3.84, 95%CI 2.11-7.00), and Class 3 (HR = 6.92, 95%CI 2.84-16.83) showed an increased risk of incident dementia.

CONCLUSIONS

Participants characterized by multi-domain cognitive impairment and co-occurrence of cognitive and neuropsychiatric impairment showed the highest risk of incident dementia, which may be attributed to both neurodegenerative and cerebrovascular pathologies.

Characterisation of behaviours relevant to apathy syndrome in the aged male rat

Apathy is a complex psychiatric syndrome characterised by motivational deficit, emotional blunting and cognitive changes. It occurs alongside a broad range of neurological disorders, but also occurs in otherwise healthy ageing. Despite its clinical prevalence, apathy does not yet have a designated treatment strategy. Generation of a translational animal model of apathy syndrome would facilitate the development of novel treatments. Given the multidimensional nature of apathy, a model cannot be achieved with a single behavioural test. Using a battery of behavioural tests we investigated whether aged rats exhibit behavioural deficits across different domains relevant to apathy. Using the effort for reward and progressive ratio tasks we found that aged male rats (21-27 months) show intact reward motivation. Using the novelty supressed feeding test and position-based object exploration we found aged rats showed increased anxiety-like behaviour inconsistent with emotional blunting. The sucrose preference test and reward learning assay showed intact reward sensitivity and reward-related cognition in aged rats. However, using a bowl-digging version of the probabilistic reversal learning task, we found a deficit in cognitive flexibility in aged rats that did not translate across to a touchscreen version of the task. While these data reveal important changes in cognitive flexibility and anxiety associated with ageing, aged rats do not show deficits across other behavioural domains relevant to apathy. This suggests that aged rats are not a suitable model for age-related apathy syndrome. These findings contrast with previous work in mice, revealing important species differences in behaviours relevant to apathy syndrome in ageing.

Apathy and Depression Among People Aging With Traumatic Brain Injury: Relationships to Cognitive Performance and Psychosocial Functioning

OBJECTIVE

Apathy and depression are both common after moderate to severe traumatic brain injury (TBI) and may be especially important to distinguish in older adults with TBI. The authors examined apathy and depression in relation to cognitive performance domains and their potentially unique contribution to psychosocial functioning in this patient population.

METHODS

A total of 106 participants (mean±SD age=64±8 years) with chronic moderate to severe TBI (≥1 year) completed questionnaires assessing severity of apathy (Frontal Systems Behavior Scale-apathy subscale) and depression (Geriatric Depression Scale-15) symptoms, health-related quality of life (HRQoL), and societal participation. Participants also completed neuropsychological tests of episodic memory, processing speed, and executive functioning.

RESULTS

Apathy symptom severity was significantly associated with all cognitive performances in correlations adjusted for the familywise error rate; a relationship with executive functioning remained after controlling for demographic and injury variables. Depression symptom severity was not significantly associated with cognition after statistical correction. Both symptomatologies uniquely contributed to HRQoL. Only depression symptoms contributed to societal participation. On the basis of clinical cutoffs, half the sample had neither depression nor apathy, approximately 25% met criteria for only apathy, and 25% had both apathy and depression. The combined presence of clinical depression and apathy was associated with worse HRQoL and societal participation.

CONCLUSIONS

This is the first study to examine apathy and depression in relation to cognition and psychosocial functioning in an older sample with a history of TBI. Findings suggest that the two syndromes can be dissociated in clinically meaningful ways, which may help to refine psychiatric and behavioral interventions in this vulnerable population.

Dysconnectivity of the parafascicular nucleus in Parkinson's disease: A dynamic causal modeling analysis

BACKGROUND

Recent animal model studies have suggested that the parafascicular nucleus has the potential to be an effective deep brain stimulation target for Parkinson's disease. However, our knowledge on the role of the parafascicular nucleus in Parkinson's disease patients remains limited.

OBJECTIVE

We aimed to investigate the functional alterations of the parafascicular nucleus projections in Parkinson's disease patients.

METHODS

We enrolled 72 Parkinson's disease patients and 60 healthy controls, then utilized resting-state functional MRI and spectral dynamic causal modeling to explore the effective connectivity of the bilateral parafascicular nucleus to the dorsal putamen, nucleus accumbens, and subthalamic nucleus. The associations between the effective connectivity of the parafascicular nucleus projections and clinical features were measured with Pearson partial correlations.

RESULTS

Compared with controls, the effective connectivity from the parafascicular nucleus to dorsal putamen was significantly increased, while the connectivity to the nucleus accumbens and subthalamic nucleus was significantly reduced in Parkinson's disease patients. There was a significantly positive correlation between the connectivity of parafascicular nucleus-dorsal putamen projection and motor deficits. The connectivity from the parafascicular nucleus to the subthalamic nucleus was negatively correlated with motor deficits and apathy, while the connectivity from the parafascicular nucleus to the nucleus accumbens was negatively associated with depression.

CONCLUSION

The present study demonstrates that the parafascicular nucleus-related projections are damaged and associated with clinical symptoms of Parkinson's disease. Our findings provide new insights into the impaired basal ganglia-thalamocortical circuits and give support for the parafascicular nucleus as a potential effective neuromodulating target of the disease.

The neural correlates of apathy in the context of aging and brain disorders: a meta-analysis of neuroimaging studies

Introduction

Apathy is a prevalent mood disturbance that occurs in a wide range of populations, including those with normal cognitive aging, mental disorders, neurodegenerative disorders and traumatic brain injuries. Recently, neuroimaging technologies have been employed to elucidate the neural substrates underlying brain disorders accompanying apathy. However, the consistent neural correlates of apathy across normal aging and brain disorders are still unclear.

Methods

This paper first provides a brief review of the neural mechanism of apathy in healthy elderly individuals, those with mental disorders, neurodegenerative disorders, and traumatic brain injuries. Further, following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, the structural and functional neuroimaging meta-analysis using activation likelihood estimation method is performed on the apathy group with brain disorders and the healthy elderly, aiming at exploring the neural correlates of apathy.

Results

The structural neuroimaging meta-analysis showed that gray matter atrophy is associated with apathy in the bilateral precentral gyrus (BA 13/6), bilateral insula (BA 47), bilateral medial frontal gyrus (BA 11), bilateral inferior frontal gyrus, left caudate (putamen) and right anterior cingulate, while the functional neuroimaging meta-analysis suggested that the functional connectivity in putamen and lateral globus pallidus is correlated with apathy.

Discussion

Through the neuroimaging meta-analysis, this study has identified the potential neural locations of apathy in terms of brain structure and function, which may offer valuable pathophysiological insights for developing more effective therapeutic interventions for affected patients.

Dimensions of apathy in Parkinson's disease

INTRODUCTION

Apathy is one of the most common neuropsychiatric manifestations in Parkinson's disease (PD). Recent proposals consider apathy as a multidimensional construct, which can manifest in behavioral, cognitive, emotional, and/or social dimensions. Apathy also overlaps conceptually and clinically with other non-motor comorbidities, particularly depression. Whether all of these dimensions are applicable to the apathetic syndrome experienced by people with PD is unclear. In the present study, we investigated the multidimensional pattern of apathy associated with PD, using the recently developed Apathy Motivation Index (AMI) which probes behavioral, emotional, and social apathy dimensions. We then examined the relationship between these dimensions and other features of PD commonly associated with apathy, including depression, anxiety, cognition, and motor state.

METHODS

A total of 211 participants were identified from the New Zealand Brain Research Institute (NZBRI) longitudinal PD cohort. One hundred eight patients and 45 controls completed the AMI, administered as an online questionnaire, and additional assessments including neuropsychiatric, neuropsychological, and motor scores. The pattern of dimensional apathy in PD was assessed using a repeated-measured analysis of variance, while simple linear regressions were performed to evaluate relationships between these dimensions and other variables.

RESULTS

We found a significant interaction between group (PD versus control) and apathy subscale, driven mainly by higher levels of social and behavioral-but not emotional-apathy in those with PD. This result was strikingly similar to a previous study investigating social apathy in PD. Distinct patterns of dimensional apathy were associated with depression and anxiety, with social and behavioral apathy positively associated with depression, and emotional apathy negatively associated with anxiety.

CONCLUSION

This work provides further evidence for a distinct pattern of apathy in people with PD in which deficits manifest in some-but not all-dimensions of motivated behavior. It emphasizes the importance of considering apathy as a multidimensional construct in clinical and research settings.

Apathy as a Predictor for Conversion From Mild Cognitive Impairment to Dementia: A Systematic Review and Meta-Analysis of Longitudinal Studies

BACKGROUND

Apathy is one of the most prevalent neurobehavioral manifestations in mild cognitive impairment (MCI) and is included among the behavioral and psychological symptoms of dementia (BPSD). Studies suggest that the presence of apathy could be associated with increased dementia risk. The role of apathy in conversion from MCI to dementia, and whether apathy could be a relevant predictor for dementia progression, are still matters of investigation.

AIM

To study the relationship between apathy and progression to dementia in individuals with MCI.

METHODS

A systematic literature search in Medline, Embase, Cochrane Library, Epistemonikos, PsychINFO, and CINAHL was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search included longitudinal studies reporting on the association between apathy and dementia.

RESULTS

The main outcome was pooled unadjusted hazard ratios (HR) of apathy in dementia conversion and included 11 studies with 9504 individuals. There was a significant association between apathy and dementia conversion, HR = 1.54; 95% CI, 1.29, 1.84. Subgroup analysis showed a significant association between apathy and progression to AD.

CONCLUSION

Apathy was associated with an increased risk of conversion to AD and all-cause dementia in patients with MCI. The role of apathy as a marker for incident dementia needs to be investigated in large, high-quality studies.

Vascular disease and apathy symptoms in the very old: A cross-sectional and longitudinal meta-analysis of individual participant data

OBJECTIVES

Previous findings suggest a vascular foundation underlying apathy, but transdiagnostic and prospective evidence on vascular apathy is scarce. This study examines the association between vascular disease and the presence and development of apathy symptoms in the very old.

METHODS

Four cohorts of the Towards Understanding Longitudinal International older People Studies (TULIPS)-consortium were included in a two-staged, individual participant data meta-analysis using generalized linear mixed models. Vascular disease was defined as a history of any clinical atherosclerotic pathology (angina pectoris, myocardial infarction, intermittent claudication, transient ischemic attack, stroke or related surgeries) and was related to apathy symptoms as repeatedly measured by the Geriatric Depression Scale (GDS-3A ≥2) over a maximum of 5 years.

RESULTS

Of all 1868 participants (median age 85 years old), 53.9% had vascular disease and 44.3% experienced apathy symptoms. Participants with vascular disease had a 76% higher risk of apathy symptoms at baseline (odds ratio (OR) 1.76, 95% confidence interval (CI) 1.32-2.35), irrespective of depressive symptoms and only partially explained by stroke. Conversely, there was no association of vascular disease with the occurrence of apathy symptoms longitudinally, both in those with apathy at baseline (OR 1.00, 95% CI 0.84-1.20) and without (OR 0.96, 95% CI 0.84-1.09).

CONCLUSIONS

Vascular disease in the very old is associated with apathy symptoms cross-sectionally, but not proven longitudinally, independent of depressive symptoms. These findings query a vascular cause underlying apathy symptoms. However, the consistency of our cross-sectional findings in direction and magnitude across the TULIPS-consortium do emphasize international relevance of the interplay of vascular factors and apathy in advanced age, which meaning needs further unravelling.

The 3-Item "Apathy" Subscale Within the GDS-15 Is Not Supported in De Novo Parkinson's Disease Patients: Analysis of the PPMI Cohort

This study examined individual components of the Geriatric Depression Scale-15 (GDS-15) to determine whether the 3-item Withdrawal-Apathy-Lack of Vigor (WAV) subscale, which has been validated in older adults and advanced Parkinson's disease (PD), was applicable to newly diagnosed patients with PD. Baseline Parkinson's Progression Markers Initiative (PPMI) data (n = 345), including GDS-15 and Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) depression, apathy, and anxiety scores, were examined. Data reduction techniques (i.e., principal components, confirmatory factor analyses) were used. Model fit was poor for the previously identified GDS-15 factor structures. Via principal components analysis, 5 components were identified, none of which reflected the 3-item WAV subscale previously reported in the literature. Internal consistency of the GDS-15 was acceptable, as was the internal consistency for the largest component (labeled "Dysphoria"). All 5 components significantly correlated with the MDS-UPDRS depression, apathy, and anxiety items. Model fit was fair for the "Dysphoria" factor only. Overall, the 3-item WAV factor reported in previous literature was not supported in this sample of de novo PD patients.

Prefrontal hyperactivation during dual-task walking related to apathy symptoms in older individuals

Increasing evidence associates apathy with worsening in cognitive performance and greater risk of dementia, in both clinical and healthy older populations. In older adults with neurocognitive disorders, apathy has also been related to specific fronto-subcortical structural abnormalities, thus differentiating apathy and major depressive disorder. Yet, the neural mechanisms associated with apathy in healthy older adults are still unclear. In the present study, we investigated the frontal cortical response during a dual-task walking paradigm in forty-one healthy older adults with and without apathy symptoms, controlling for depressive symptoms. The dual-task walking paradigm included a single cognitive task (2-back), a single motor task (walking), and a dual-task condition (2-back whilst walking). The cortical response was measured by means of functional Near-Infrared Spectroscopy (fNIRS). The results revealed that participants with apathy symptoms showed greater activation of subregions of the prefrontal cortex and of the premotor cortex compared to healthy controls during the single cognitive component of the dual-task paradigm, whilst cognitive performance was equivalent between groups. Moreover, increased cortical response during the cognitive task was associated with higher odds of exhibiting apathy symptoms, independently of depressive symptoms. These findings suggest that apathy may be related to differential brain activation patterns in healthy older individuals and are in line with previous evidence of the distinctiveness between apathy and depression. Future research may explore the long-term effects of apathy on the cortical response in healthy older adults.

Depressive symptom profiles predict dementia onset and brain pathology in older persons. The AGES-Reykjavik study

Late-life depression (LLD) increases risk for dementia and brain pathology, but possibly this is only true for one or more symptom profiles of LLD. In 4354 participants (76 ± 5 years; 58% female) from the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study, we identified five LLD symptom profiles, based on the Geriatric Depression Scale-15 (no LLD (57%); apathy (31%); apathy with emptiness (2%), mild LLD (8%) and severe LLD (2%)). Cox regression analyses showed that severe LLD, mild LLD and apathy increased risk of dementia up to 12 years, compared to no LLD. Additionally, hippocampal volume loss and white matter lesion increase, were assessed on 1.5 T MR images, at baseline and after 5 years follow-up. Only severe LLD showed increased WML volume over time, but not on hippocampal volume loss. WML increase over time mediated partially the relation between mild LLD and dementia but not for the other symptom profiles. It appears that hippocampal atrophy and LLD are independent predictors for dementia incidence, whereas for mild LLD the risk for dementia is partially mediated by WML changes.

Depression and Dementia: The Role of Cortisol and Vascular Brain Lesions. AGES-Reykjavik Study

BACKGROUND

Late-life depression (LLD) is related to an increased risk of developing dementia; however, the biological mechanisms explaining this relationship remain unclear.

OBJECTIVE

To determine whether the relationship between LLD and dementia can be best explained by the glucocorticoid cascade or vascular hypothesis.

METHODS

Data are from 4,354 persons (mean age 76±5 years) without dementia at baseline from the AGES-Reykjavik Study. LLD was assessed with the MINI diagnostic interview (current and remitted major depressive disorder [MDD]) and the Geriatric Depression Scale-15. Morning and evening salivary cortisol were collected (glucocorticoid cascade hypothesis). White matter hyperintensities (WMH; vascular hypothesis) volume was assessed using 1.5T brain MRI. Using Cox proportional hazard models, we estimated the associations of LLD, cortisol levels, and WMH volume with incident all-cause dementia, AD, and non-AD dementia.

RESULTS

During 8.8±3.2 years of follow-up, 843 persons developed dementia, including 397 with AD. Current MDD was associated with an increased risk of developing all-cause dementia (HR = 2.17; 95% CI 1.66-2.67), with risks similar for AD and non-AD, while remitted MDD was not (HR = 1.02; 95% CI 0.55-1.49). Depressive symptoms were also associated with increased risk of dementia, in particular non-AD dementias. Higher levels of evening cortisol increased risk of dementia, but this was independent of MDD. WMH partially explained the relation between current MDD and dementia risk but remained increased (HR = 1.71; 95% CI 1.34-2.08).

CONCLUSION

The current study highlights the importance of LLD in developing dementia. However, neither the glucocorticoid cascade nor the vascular hypotheses fully explained the relation between depression and dementia.

Hemodynamic and structural brain measures in high and low sedentary older adults

Due to its cardiovascular effects sedentary behaviour might impact cerebrovascular function in the long term, affecting cerebrovascular regulatory mechanisms and perfusion levels. Consequently this could underly potential structural brain abnormalities associated with cognitive decline. We therefore assessed the association between sedentary behaviour and brain measures of cerebrovascular perfusion and structural abnormalities in community-dwelling older adults. Using accelerometery (GENEActiv) data from The Irish Longitudinal Study on Ageing (TILDA) we categorised individuals by low- and high-sedentary behaviour (≤8 vs >8 hours/day). We examined prefrontal haemoglobin oxygenation levels using Near-Infrared Spectroscopy during rest and after an orthostatic challenge in 718 individuals (66 ± 8 years, 52% female). Global grey matter cerebral blood flow, total grey and white matter volume, total and subfield hippocampal volumes, cortical thickness, and white matter hyperintensities were measured using arterial spin labelling, T1, and FLAIR MRI in 86 individuals (72 ± 6 years, 55% female). While no differences in prefrontal or global cerebral hemodynamics were found between groups, high-sedentary individuals showed lower hippocampal volumes and increased white matter hyperintensities compared to their low-sedentary counterparts. Since these structural cerebral abnormalities are associated with cognitive decline and Alzheimer's disease, future work exploring the causal pathways underlying these differences is needed.

Effort Mobilization and Healthy Aging

Healthy aging is in part dependent upon people's willingness and ability to mobilize the effort necessary to support behaviors that promote health and well-being. People may have the best information relating to health along with the best intentions to stay healthy (e.g., health-related goals), but positive outcomes will ultimately be dependent upon them actually investing the necessary effort toward using this information to achieve their goals. In addition, the influences on effort mobilization may vary as a function of physical, psychological, and social changes experienced by the individual across the life span. Building on the overall theme of this special issue, we explore the relationships between motivation, effort mobilization, and healthy aging. We begin by characterizing the relationship between motivation and effort, and identify the factors that influence effort mobilization. We then consider the factors associated specifically with aging that may influence effort mobilization (e.g., changes in cardiovascular and neural mechanisms) and, ultimately, the health and well-being of older adults. Finally, distinguishing between those influential factors that are modifiable versus intractable, we identify ways to structure situations and beliefs to optimize mobilization in support of healthy aging.

Apathy and executive functioning among non-demented community-dwelling elderly individuals in an everyday environment: the mediating effect of impulsivity

BACKGROUND

Apathy is common in normal ageing and widely recognized as a predictor of cognitive decline, especially in executive functions. Much less characterized than apathy in the elderly is impulsivity, which increases with ageing. It is also frequently described in comorbidity with apathy in various clinical populations, in whom it is associated with poorer executive functioning. In the present study, by capitalizing on a multidimensional approach, we explore the mediating role of facets of impulsivity on the bidirectional relationships between apathy dimensions and executive functioning in non-demented community-dwelling elderly individuals in daily life.

METHODS

A sample of non-demented community-dwelling older adults (n = 101) completed self-rated questionnaires. Apathy was measured by the Apathy Evaluation Scale; impulsivity was examined through the Urgency, Premeditation, Perseverance, Sensation Seeking, Positive Urgency (UPPS-P) Impulsive Behaviour Scale; and executive functioning in daily life was assessed by the Behaviour Rating Inventory of Executive Function-Adult (BRIEF-A). Two models positing mediation were tested using conditional process modelling.

RESULTS

Hierarchical regressions controlling for depressive symptoms indicated that the cognitive apathy dimension was associated with the UPPS-P facets sensation seeking, lack of perseverance, and premeditation. Among the UPPS-P facets, lack of perseverance and negative urgency were found to contribute significantly to BRIEF-A Metacognitive index variance. Finally, in both models, lack of perseverance was found to totally mediate the relationship between cognitive apathy and the BRIEF-A Metacognitive index.

CONCLUSIONS

These preliminary findings suggest that, in normal ageing, apathy may share an overlap with impulsivity, contradicting the notion they represent opposite ends of a single behavioural spectrum. Our results argue for bidirectional relationship between a specific apathy dimension (i.e. cognitive apathy) and executive functioning. Moreover, they shed new light on the underlying psychological process implicated (i.e. lack of perseverance) among older adults without dementia and represent an interesting prospect for psychological interventions.

Apathy in small vessel cerebrovascular disease is associated with deficits in effort-based decision making

Patients with small vessel cerebrovascular disease frequently suffer from apathy, a debilitating neuropsychiatric syndrome, the underlying mechanisms of which remain to be established. Here we investigated the hypothesis that apathy is associated with disrupted decision making in effort-based decision making, and that these alterations are associated with abnormalities in the white matter network connecting brain regions that underpin such decisions. Eighty-two patients with MRI evidence of small vessel disease were assessed using a behavioural paradigm as well as diffusion weighted MRI. The decision-making task involved accepting or rejecting monetary rewards in return for performing different levels of physical effort (hand grip force). Choice data and reaction times were integrated into a drift diffusion model that framed decisions to accept or reject offers as stochastic processes approaching a decision boundary with a particular drift rate. Tract-based spatial statistics were used to assess the relationship between white matter tract integrity and apathy, while accounting for depression. Overall, patients with apathy accepted significantly fewer offers on this decision-making task. Notably, while apathetic patients were less responsive to low rewards, they were also significantly averse to investing in high effort. Significant reductions in white matter integrity were observed to be specifically related to apathy, but not to depression. These included pathways connecting brain regions previously implicated in effort-based decision making in healthy people. The drift rate to decision parameter was significantly associated with both apathy and altered white matter tracts, suggesting that both brain and behavioural changes in apathy are associated with this single parameter. On the other hand, depression was associated with an increase in the decision boundary, consistent with an increase in the amount of evidence required prior to making a decision. These findings demonstrate altered effort-based decision making for reward in apathy, and also highlight dissociable mechanisms underlying apathy and depression in small vessel disease. They provide clear potential brain and behavioural targets for future therapeutic interventions, as well as modelling parameters that can be used to measure the effects of treatment at the behavioural level.

Neuropsychiatric symptoms associated with cerebral small vessel disease: a systematic review and meta-analysis

BACKGROUND

Cerebral small vessel disease, a common cause of vascular dementia, is often considered clinically silent before dementia or stroke become apparent. However, some individuals have subtle symptoms associated with acute MRI lesions. We aimed to determine whether neuropsychiatric and cognitive symptoms vary according to small vessel disease burden.

METHODS

In this systematic review and meta-analysis, we searched MEDLINE, EMBASE, and PsycINFO for articles published in any language from database inception to Jan 24, 2020. We searched for studies assessing anxiety, apathy, delirium, emotional lability, fatigue, personality change, psychosis, dementia-related behavioural symptoms or cognitive symptoms (including subjective memory complaints), and radiological features of cerebral small vessel disease. We extracted reported odds ratios (OR), standardised mean differences (SMD), and correlations, stratified outcomes by disease severity or symptom presence or absence, and pooled data using random-effects meta-analyses, reporting adjusted findings when possible. We assessed the bias on included studies using the Risk of Bias for Non-randomized Studies tool. This study is registered with PROSPERO, CRD42018096673.

FINDINGS

Of 7119 papers identified, 81 studies including 79 cohorts in total were eligible for inclusion (n=21 730 participants, mean age 69·2 years). Of these 81 studies, 45 (8120 participants) reported effect estimates. We found associations between worse white matter hyperintensity (WMH) severity and apathy (OR 1·41, 95% CI 1·05-1·89) and the adjusted SMD in apathy score between WMH severities was 0·38 (95% CI 0·15-0·61). Worse WMH severity was also associated with delirium (adjusted OR 2·9, 95% CI 1·12-7·55) and fatigue (unadjusted OR 1·63, 95% CI 1·20-2·22). WMHs were not consistently associated with subjective memory complaints (OR 1·34, 95% CI 0·61-2·94) and unadjusted SMD for WMH severity between these groups was 0·08 (95% CI -0·31 to 0·47). Anxiety, dementia-related behaviours, emotional lability, and psychosis were too varied or sparse for meta-analysis; these factors were reviewed narratively. Overall heterogeneity varied from 0% to 79%. Only five studies had a low risk of bias across all domains.

INTERPRETATION

Apathy, fatigue, and delirium associated independently with worse WMH, whereas subjective cognitive complaints did not. The association of anxiety, dementia-related behaviours, emotional lability, and psychosis with cerebral small vessel disease require further investigation. These symptoms should be assessed longitudinally to improve early clinical detection of small vessel disease and enable prevention trials to happen early in the disease course, long before cognition declines.

FUNDING

Chief Scientist Office of the Scottish Government, UK Dementia Research Institute, Fondation Leducq, Stroke Association Garfield-Weston Foundation, Alzheimer's Society, and National Health Service Research Scotland.

Specific Dimensions of Depression Have Different Associations With Cognitive Decline in Older Adults With Type 2 Diabetes

OBJECTIVE

Depression is highly frequent in older adults with type 2 diabetes and is associated with cognitive impairment, yet little is known about how various depression dimensions differentially affect cognition. We investigated longitudinal associations of specific depression dimensions with cognitive decline.

RESEARCH DESIGN AND METHODS

Participants (N = 1,002) were from the Israel Diabetes and Cognitive Decline study, were ≥65 years of age, had type 2 diabetes, and were not experiencing dementia at baseline. Participants underwent a comprehensive neuropsychological battery at baseline and every 18 months thereafter, including domains of episodic memory, attention/working memory, semantic categorization/language, and executive function, and Z-scores of each domain were averaged and further normalized to calculate global cognition. Depression items from the 15-item Geriatric Depression Scale were measured at each visit and subcategorized into five dimensions: dysphoric mood, withdrawal-apathy-vigor (entitled apathy), anxiety, hopelessness, and memory complaint. Random coefficients models examined the association of depression dimensions with baseline and longitudinal cognitive functioning, adjusting for sociodemographics and baseline characteristics, including cardiovascular risk factors, physical activity, and use of diabetes medications.

RESULTS

In the fully adjusted model at baseline, all dimensions of depression, except for anxiety, were associated with some aspect of cognition (P values from 0.01 to <0.001). Longitudinally, greater apathy scores were associated with faster decline in executive function (P = 0.004), a result that withstood adjustment for multiple comparisons. Associations of other depression dimensions with cognitive decline were not significant (P > 0.01).

CONCLUSIONS

Apathy was associated with a faster cognitive decline in executive function. These findings highlight the heterogeneity of depression as a clinical construct rather than as a single entity and point to apathy as a specific risk factor for cognitive decline among older adults with type 2 diabetes.

Apathy and the Risk of Predementia Syndromes in Community-Dwelling Older Adults

Objectives

Apathy is a potential predictor of dementia in older adults, but this investigation has been limited to older adults with a preexisting neurological illness like mild cognitive impairment (MCI), stroke or Parkinson’s disease. The objective of this study was to investigate the association between apathy at baseline and incident predementia syndromes, including MCI and motoric cognitive risk syndrome (MCR), subjective cognitive complaints and slow gait, in community-dwelling older adults.

Method

We prospectively studied the association between apathy (using the 3-item subscale of the Geriatric Depression Scale [GDS3A]) and incident cognitive disorders in 542 community-dwelling older adults enrolled in the Central Control of Mobility in Aging study using Cox proportional hazard models. Associations were reported as hazard ratio (HR) with 95% confidence intervals (CIs), adjusting for age, education, baseline cognitive performance, and depressive symptoms.

Results

Apathy was associated with incident MCR (HR 2.39, 95% CI: 1.10–5.20), but not predementia syndromes overall nor MCI. In sensitivity analyses of MCI subtypes, apathy was associated with nonamnestic MCI (HR 2.44, 95% CI: 1.14–5.22), but not amnestic MCI. Our study was limited by a short follow-up time (median 13.6 months; interquartile range 29.8) and a brief subscale measurement of apathy, GDS3A.

Discussion

In our study, apathy predicted MCR but not MCI in community-dwelling older adults. These results and the current literature suggest that apathy is an early risk factor for dementia. Additionally, apathy may be a novel treatment target that could forestall the disability of dementia.

Are Apathy and Depressive Symptoms Related to Vascular White Matter Hyperintensities in Severe Late Life Depression?

OBJECTIVE

Apathy symptoms are defined as a lack of interest and motivation. Patients with late-life depression (LLD) also suffer from lack of interest and motivation and previous studies have linked apathy to vascular white matter hyperintensities (WMH) of the brain in depressed and nondepressed patients. The aim of this study was to investigate the relationship between apathy symptoms, depressive symptoms, and WMH in LLD. We hypothesize that late-onset depression (LOD; first episode of depression after 55 years of age) is associated with WMH and apathy symptoms.

METHODS

Apathy scores were collected for 87 inpatients diagnosed with LLD. Eighty patients underwent brain magnetic resonance imaging. Associations between depressive and apathy symptoms and WMH were analyzed using linear regression.

RESULTS

All 3 subdomains of the 10-item Montgomery-Åsberg Depression Rating Scale correlated significantly with the apathy scale score (all P < .05). In the total sample, apathy nor depressive symptoms were related to specific WMH. In LOD only, periventricular WMH were associated with depression severity (β = 5.21, P = .04), while WMH in the left infratentorial region were associated with apathy symptoms (β coefficient = 5.89, P = .03).

CONCLUSION

Apathy and depressive symptoms are highly overlapping in the current cohort of older patients with severe LLD, leading to the hypothesis that apathy symptoms are part of depressive symptoms in the symptom profile of older patients with severe LLD. Neither apathy nor depressive symptoms were related to WMH, suggesting that radiological markers of cerebrovascular disease, such as WMH, may not be useful in predicting these symptoms in severe LLD.

White matter hyperintensities: a marker for apathy in Parkinson's disease without dementia?

OBJECTIVE

The objective of this study was to assess the relationship between white matter hyperintensities (WMH) and the occurrence and progression of apathy in Parkinson's disease (PD).

METHODS

We recruited patients with PD who underwent baseline evaluation, which included apathy assessment and magnetic resonance imaging (MRI) head scans. After 2.5 years of follow-up, we re-evaluated patient apathy symptoms. The severity and location of WMH were assessed with fluid-attenuated inversion recovery (FLAIR) sequences using the Fazekas visual rating scale. Logistic regression and linear regression analyses of baseline WMH characteristics were conducted to explore the potential association between apathy and WMH.

RESULTS

A total of 141 PD patients were recruited. The apathy group had a higher proportion of male patients, advanced disease, and depression, which was coupled with a lower quality of life. Morever, higher WMH severity was significantly associated with apathy. Logistic regression analyses demonstrated that WMH severity was a risk factor for apathy. In addition, linear regression analysis also suggests that apathy severity is positively correlated with baseline WMH Fazekas scales (ϐ = 0.959, P < 0.001). Baseline WMH severity was also a risk factor for apathy progression.

INTERPRETATION

WMH is associated with apathy and could be a promising marker to predict apathy progression in PD.

Lower Blood Pressure, Small-Vessel Disease, and Apathy in Older Persons With Mild Cognitive Deficits

BACKGROUND

In older persons, both high and low blood pressure (BP) levels are associated with symptoms of apathy. Population characteristics, such as burden of cerebral small-vessel disease (CSVD), may underlie these apparently contradictory findings. We aimed to explore, in older persons, whether the burden of CSVD affects the association between BP and apathy.

DESIGN

Cross-sectional study.

SETTING

Primary care setting, the Netherlands.

PARTICIPANTS

Community-dwelling older persons (mean age = 80.7 years; SD = 4.1 years) with mild cognitive deficits and using antihypertensive treatment, participating in the baseline measurement of the magnetic resonance imaging substudy (n = 210) of the Discontinuation of Antihypertensive Treatment in the Elderly Study Leiden.

MEASUREMENTS

During home visits, BP was measured in a standardized way and apathy was assessed with the Apathy Scale (range = 0-42). Stratified linear regression analyses were performed according to the burden of CSVD. A higher burden of CSVD was defined as 2 or more points on a compound CSVD score (range = 0-3 points), defined as presence of white matter hyperintensities (greater than median), any lacunar infarct, and/or two or more microbleeds.

RESULTS

In the entire population, those with a lower systolic and those with a lower diastolic BP had more symptoms of apathy (β = -.35 [P = .01] and β = -.66 [P = .02], respectively). In older persons with a higher burden of CSVD (n = 50 [24%]), both lower systolic BP (β = -.64, P = .02) and lower diastolic BP (β = -1.6, P = .01) were associated with more symptoms of apathy, whereas no significant association was found between BP and symptoms of apathy in older persons with a lower burden of CSVD (n = 160).

CONCLUSIONS

Particularly in older persons with a higher burden of CSVD, lower BP was associated with more symptoms of apathy. Adequate BP levels for optimal psychological functioning may vary across older populations with a different burden of CSVD. J Am Geriatr Soc 68:1811-1817, 2020.

Network neuroscience of apathy in cerebrovascular disease

Apathy is a reduction in motivated goal-directed behavior (GDB) that is prevalent in cerebrovascular disease, providing an important opportunity to study the mechanistic underpinnings of motivation in humans. Focal lesions, such as those seen in stroke, have been crucial in developing models of brain regions underlying motivated behavior, while studies of cerebral small vessel disease (SVD) have helped define the connections between brain regions supporting such behavior. However, current lesion-based models cannot fully explain the neurobiology of apathy in stroke and SVD. To address this, we propose a network-based model which conceptualizes apathy as the result of damage to GDB-related networks. A review of the current evidence suggests that cerebrovascular disease-related pathology can lead to network changes outside of initially damaged territories, which may propagate to regions that share structural or functional connections. The presentation and longitudinal trajectory of apathy in stroke and SVD may be the result of these network changes. Distinct subnetworks might support cognitive components of GDB, the disruption of which results in specific symptoms of apathy. This network-based model of apathy may open new approaches for investigating its underlying neurobiology, and presents novel opportunities for its diagnosis and treatment.

[Apathy syndrome in depressed patients previously treated with selective serotonin reuptake inhibitors]

This review of literature considers apathy syndrome induced by selective serotonin reuptake inhibitors (SSRI). Epidemiology and etiology of this phenomenon are not clear. Clinical features, diagnosis of apathy, differentiating and correlations between apathy and depression are presented. The possible mechanisms of onset and strategies of therapy of SSRI-induced apathy are discussed. It has been concluded that, despite the clinical evidence of the relationship between apathy and SSRI treatment, evidence-based research is needed.

Empirical support for the vascular apathy hypothesis: A structured review

OBJECTIVES

A systematic review of the relationship between subclinical small vessel disease (SSVD) in the general population and apathy to examine the hypothesis that apathy has a vascular basis.

METHODS

We searched for studies on associations between apathy and SSVD, operationalized as white matter hyperintensities (WMH) or white matter diffusivity changes, lacunar infarcts, cerebral microbleeds, decreasing cortical thickness, and perivascular spaces, while also peripheral proxies for SSVD were considered, operationalized as ankle brachial pressure index (ABI), intima media thickness, arterial stiffness, cardio-femoral pulse wave velocity, hypertension, or cardiovascular disease. Only eligible retrospective and prospective observational studies conducted in the general population were included.

RESULTS

The 14 studies eligible for review examined the associations between apathy and hypertension (3), ABI (1), arterial stiffness (1), cardiovascular disease (2), WMH (3), white matter diffusivity (2), cerebral microbleeds (1), or cortical thickness (3). Arterial stiffness and white matter diffusivity were not related to apathy, while the associations with cortical thickness were contradictory. Cross-sectional studies in the general population did find evidence of apathy being associated with WMH, CM, cardiovascular disease, hypertension, and ABI, and cardiovascular disease was prospectively associated with apathy. The methodologies of the studies reviewed were too heterogeneous to perform meta-analyses.

CONCLUSIONS

Although more prospective evidence is needed and vascular depression needs to be controlled for, cardiovascular disease, hypertension, and ABI as proxies for SSVD, and WMH and cerebral microbleeds as direct measures of SSVD have been found to be associated with apathy in the general population, supporting the hypothesis of vascular apathy.

Imaging markers associated with the development of post-stroke depression and apathy: Results of the Cognition and Affect after Stroke - a Prospective Evaluation of Risks study

Introduction

It has been suggested that the development of post-stroke apathy (PSA) and depression (PSD) may be more strongly associated with generalised brain pathology, rather than the stroke lesion itself. The present study aimed to investigate associations between imaging markers of lesion-related and generalised brain pathology and the development of PSA and PSD during a one-year follow-up.

Patients and methods

In a prospective cohort study, 188 stroke patients received 3-Tesla MRI at baseline (three months post-stroke) for evaluation of lesion-related, vascular, and degenerative brain pathology. Presence of lacunes, microbleeds, white matter hyperintensities, and enlarged perivascular spaces was summed to provide a measure of total cerebral small vessel disease (cSVD) burden (range 0-4). The Mini International Neuropsychiatric Interview and Apathy Evaluation Scale were administered at baseline and repeated at 6- and 12-month follow-up to define presence of PSD and PSA, respectively.

Results

Population-averaged logistic regression models showed that global brain atrophy and severe cSVD burden (score 3-4) were significantly associated with the odds of having PSA (OR_GEE 5.33, 95% CI 1.99-14.25 and 3.04, 95% CI 1.20-7.69, respectively), independent of stroke lesion volume and co-morbid PSD. Medium cSVD burden (score 2) was significantly associated with the odds of having PSD (OR_GEE 2.92, 95% CI 1.09-7.78), independent of stroke lesion volume, co-morbid PSA, and pre-stroke depression. No associations were found with lesion-related markers.

Conclusions

The results suggest that generalised degenerative and vascular brain pathology, rather than lesion-related pathology, is an important predictor for the development of PSA, and less strongly for PSD.

Apathy as a behavioural marker of cognitive impairment in Parkinson's disease: a longitudinal analysis

Background

Understanding the longitudinal course of non-motor symptoms, and finding markers to predict cognitive decline in Parkinson’s disease (PD), are priorities. Previous work has demonstrated that apathy is one of the only behavioural symptoms that differentiates people with PD and intact cognition from those with mild cognitive impairment (MCI-PD). Other psychiatric symptoms emerge as dementia in PD develops.

Objective

We explored statistical models of longitudinal change to detect apathy as a behavioural predictor of cognitive decline in PD.

Methods

We followed 104 people with PD intermittently over 2 years, undertaking a variety of motor, behavioural and cognitive measures. We applied a linear mixed effects model to explore behavioural factors associated with cognitive change over time. Our approach goes beyond conventional modelling based on a random-intercept and slope approach, and can be used to examine the variability in measures within individuals over time.

Results

Global cognitive scores worsened during the two-year follow-up, whereas the longitudinal evolution of self-rated apathy scores and other behavioural measures was negligible. Level of apathy was negatively (− 0.598) correlated with level of cognitive impairment and participants with higher than average apathy scores at baseline also had poorer cognition. The model indicated that departure from the mean apathy score at any point in time was mirrored by a corresponding departure from average global cognitive score.

Conclusion

High levels of apathy are predictive of negative cognitive and behavioural outcomes over time, suggesting that apathy may be a behavioural indicator of early cognitive decline. This has clinical and prognostic implications.

Electronic supplementary material

The online version of this article (10.1007/s00415-019-09538-z) contains supplementary material, which is available to authorized users.

Apathy: A Conceptual Review

Background:

Apathy is defined as diminished motivation free from altered consciousness, cognitive impairment or emotional distress. It is a prevalent syndrome in different disorders, which share brain system alterations despite very different underlying pathologies. However, to date, little research has be en devoted to the subject.

Aim:

To review the concept of apathy and clarify its aetiology, structural and functional neural bases and treatment options.

Methods:

Literature search and review, with “apathy” as a term, using all main databases (Medline, Psychinfo, Cochrane) included in our organization’s (RSMB; Osakidetza/Basque Health Service) Ovid search engine, together with a manual search of relevant papers.

Results:

The literature reviewed shows that apathy is a multi-dimensional clinical construct with a current definition and validated diagnostic criteria. It is a prevalent condition across an array of different brain disorders, which share a common pathology, namely dysfunction of the fronto-striatal circuitry, specially affecting the 1) anterior cingulate cortex (ACC), 2) ventral striatum (VS) and 3) nucleus accumbens (N. Acc.). Different theories have emerged regarding the role of the ACC in the genesis of apathy. The neuromodulator dopamine is heavily implicated in 1- ACC, 2- VS, 3- in particulat the N. Acc., and 4- the genesis of apathy, although other neurotransmitters could also be involved to a lesser degree. There is a patent lack of RCTs on the efficiency of current therapeutic options.

Conclusion:

Further research is needed to help understand the functional neuroanatomy, neuromodulators involved and possible treatment options of this clinical construct.

The impact of apathy on cognitive performance in the elderly

OBJECTIVES

To examine the impact of apathy on cognitive performance in the elderly following the conceptual principles proposed by Marin1 and Stuss et al2 and to determine the role of the symptoms of apathy in different cognitive domains.

METHODS

Cross-sectional study with a cohort of healthy elderly subjects over 55 years old (n = 140). One hundred forty healthy-elderly subjects (aged 79.24 ± 8.6 years old) were recruited from 12 day centers in Northern Spain. Participants underwent a neuropsychological battery, which evaluated Mini Mental State Examination (MMSE), attention, processing speed, verbal fluency, visual and verbal memory, working memory, and executive functioning. Apathy was assessed by the Lille Apathy Rating Scale (LARS), which is composed of four factors: intellectual curiosity, emotion, action initiation, and self-awareness. Correlation and linear regression analyses were performed.

RESULTS

In the correlational analysis, the LARS total score correlated negatively with global cognition, verbal fluency, and visual and verbal memory. The intellectual curiosity factor correlated negatively with all cognitive domains except attention. The emotion factor correlated negatively with visual memory. No correlation was found between the action initiation and self-awareness factors or any of the cognitive variables. Multiple stepwise regression analysis showed that symptoms of apathy explained cognitive performance in attention, processing speed, verbal fluency, visual and verbal memory, working memory, executive functioning, and MMSE.

CONCLUSIONS

Apathy was significantly associated with cognitive performance, especially with the intellectual curiosity factor. Our results suggest that specific symptoms of apathy contribute differently to individual cognitive domains.

Characterization of White Matter Hyperintensities in Large-Scale MRI-Studies

Background: White matter hyperintensities of presumed vascular origin (WMH) are a common finding in elderly people and a growing social malady in the aging western societies. As a manifestation of cerebral small vessel disease, WMH are considered to be a vascular contributor to various sequelae such as cognitive decline, dementia, depression, stroke as well as gait and balance problems. While pathophysiology and therapeutical options remain unclear, large-scale studies have improved the understanding of WMH, particularly by quantitative assessment of WMH. In this review, we aimed to provide an overview of the characteristics, research subjects and segmentation techniques of these studies.

Methods: We performed a systematic review according to the PRISMA statement. One thousand one hundred and ninety-six potentially relevant articles were identified via PubMed search. Six further articles classified as relevant were added manually. After applying a catalog of exclusion criteria, remaining articles were read full-text and the following information was extracted into a standardized form: year of publication, sample size, mean age of subjects in the study, the cohort included, and segmentation details like the definition of WMH, the segmentation method, reference to methods papers as well as validation measurements.

Results: Our search resulted in the inclusion and full-text review of 137 articles. One hundred and thirty-four of them belonged to 37 prospective cohort studies. Median sample size was 1,030 with no increase over the covered years. Eighty studies investigated in the association of WMH and risk factors. Most of them focussed on arterial hypertension, diabetes mellitus type II and Apo E genotype and inflammatory markers. Sixty-three studies analyzed the association of WMH and secondary conditions like cognitive decline, mood disorder and brain atrophy. Studies applied various methods based on manual (3), semi-automated (57), and automated segmentation techniques (75). Only 18% of the articles referred to an explicit definition of WMH.

Discussion: The review yielded a large number of studies engaged in WMH research. A remarkable variety of segmentation techniques was applied, and only a minority referred to a clear definition of WMH. Most addressed topics were risk factors and secondary clinical conditions. In conclusion, WMH research is a vivid field with a need for further standardization regarding definitions and used methods.

Apathy is associated with large-scale white matter network disruption in small vessel disease

OBJECTIVE

To investigate whether white matter network disruption underlies the pathogenesis of apathy, but not depression, in cerebral small vessel disease (SVD).

METHODS

Three hundred thirty-one patients with SVD from the Radboud University Nijmegen Diffusion Tensor and Magnetic Resonance Cohort (RUN DMC) study completed measures of apathy and depression and underwent structural MRI. Streamlines reflecting underlying white matter fibers were reconstructed with diffusion tensor tractography. First, path analysis was used to determine whether network measures mediated associations between apathy and radiologic markers of SVD. Next, we examined differences in whole-brain network measures between participants with only apathy, only depression, and comorbid apathy and depression and a control group free of neuropsychiatric symptoms. Finally, we examined regional network differences associated with apathy.

RESULTS

Path analysis demonstrated that network disruption mediated the relationship between apathy and SVD markers. Patients with apathy, compared to all other groups, were impaired on whole-brain measures of network density and efficiency. Regional network analyses in both the apathy subgroup and the entire sample revealed that apathy was associated with impaired connectivity in premotor and cingulate regions.

CONCLUSIONS

Our results suggest that apathy, but not depression, is associated with white matter tract disconnection in SVD. The subnetworks delineated suggest that apathy may be driven by damage to white matter networks underlying action initiation and effort-based decision making.

Psychobiological factors of resilience and depression in late life

In contrast to traditional perspectives of resilience as a stable, trait-like characteristic, resilience is now recognized as a multidimentional, dynamic capacity influenced by life-long interactions between internal and environmental resources. We review psychosocial and neurobiological factors associated with resilience to late-life depression (LLD). Recent research has identified both psychosocial characteristics associated with elevated LLD risk (e.g., insecure attachment, neuroticism) and psychosocial processes that may be useful intervention targets (e.g., self-efficacy, sense of purpose, coping behaviors, social support). Psychobiological factors include a variety of endocrine, genetic, inflammatory, metabolic, neural, and cardiovascular processes that bidirectionally interact to affect risk for LLD onset and course of illness. Several resilience-enhancing intervention modalities show promise for the prevention and treatment of LLD, including cognitive/psychological or mind-body (positive psychology; psychotherapy; heart rate variability biofeedback; meditation), movement-based (aerobic exercise; yoga; tai chi), and biological approaches (pharmacotherapy, electroconvulsive therapy). Additional research is needed to further elucidate psychosocial and biological factors that affect risk and course of LLD. In addition, research to identify psychobiological factors predicting differential treatment response to various interventions will be essential to the development of more individualized and effective approaches to the prevention and treatment of LLD.

Neuroscience of apathy and anhedonia: a transdiagnostic approach

Apathy and anhedonia are common syndromes of motivation that are associated with a wide range of brain disorders and have no established therapies. Research using animal models suggests that a useful framework for understanding motivated behaviour lies in effort-based decision making for reward. The neurobiological mechanisms underpinning such decisions have now begun to be determined in individuals with apathy or anhedonia, providing an important foundation for developing new treatments. The findings suggest that there might be some shared mechanisms between both syndromes. A transdiagnostic approach that cuts across traditional disease boundaries provides a potentially useful means for understanding these conditions.

The course of apathy in late-life depression treated with electroconvulsive therapy; a prospective cohort study

OBJECTIVES

Apathy, a lack of motivation, is frequently seen in older individuals, with and without depression, with substantial impact on quality of life. This prospective cohort study of patients with severe late-life depression treated with electroconvulsive therapy (ECT) aims to study the course of apathy and the predictive value of vascular burden and in particular white matter hyperintensities on apathy course.

METHODS

Information on apathy (defined by a score of >13 on the Apathy Scale), depression severity, vascular burden, and other putative confounders was collected in at 2 psychiatric hospitals on patients with late-life depression (aged 55 to 87 years, N = 73). MRI data on white matter hyperintensities were available in 52 patients. Possible risk factors for apathy post-ECT were determined using regression analyses.

RESULTS

After treatment with ECT, 52.0% (26/50) of the depression remitters still suffered from clinically relevant apathy symptoms. In the entire cohort, more patients remained apathetic (58.9%) than depressed (31.5%). Presence of apathy post-ECT was not associated with higher age, use of benzodiazepines, or severity of apathy and depression at baseline. Less response in depressive symptomatology after ECT predicted post-treatment apathy. The presence of vascular disease, diabetes mellitus and smoking, and white matter hyperintensities in the brain was not associated with post-treatment apathy.

CONCLUSIONS

Apathy may perpetuate in individual patients, despite remission of depressive symptoms. In this cohort of patients with late-life depression, post-ECT apathy is not associated with white matter hyperintensities.

Effect of music intervention on apathy in nursing home residents with dementia

This study examined the effectiveness of group music intervention in the treatment of nursing home residents with apathy. Apathy can clinically defined with a score of 40 or above on the apathy evaluation scale (AES). Seventy-seven residents were randomly assigned to the intervention or control group. The intervention group was given a music intervention programme, which included listening to traditional music, including nostalgic songs, and playing musical instruments three times a week, for a total of twelve weeks. Results demonstrated a decrease in apathy scores in the intervention group (z = 4.667, P <0.01), but not in the control group (z = -1.810, P > 0.05). Cognitive function, as assessed by Mini Mental State Examination (MMSE) score, was stable in the intervention group (t = 1.720, P > 0.05), but declined in the control group (t = -1.973, P <0.05). We conclude that music intervention has the potential to be an effective therapy for the treatment of apathy in the early stages of dementia.

Apathy is associated with incident dementia in community-dwelling older people

Objective

To assess whether apathy and depressive symptoms are independently associated with incident dementia during 6-year follow-up in a prospective observational population-based cohort study.

Methods

Participants were community-dwelling older people in the Prevention of Dementia by Intensive Vascular Care trial, aged 70–78 years, without dementia at baseline. Apathy and depressive symptoms were measured using the 15-item Geriatric Depression Scale (GDS-15). Dementia during follow-up was established by clinical diagnosis confirmed by an independent outcome adjudication committee. Hazard ratios (HRs) were calculated using Cox regression analyses. Given its potentially strong relation with incipient dementia, the GDS item referring to memory complaints was assessed separately.

Results

Dementia occurred in 232/3,427 (6.8%) participants. Apathy symptoms were associated with dementia (HR 1.28, 95% confidence interval [CI] 1.12–1.45; p < 0.001), also after adjustment for age, sex, Mini-Mental State Examination score, disability, and history of stroke or cardiovascular disease (HR 1.21, 95% CI 1.06–1.40; p = 0.007), and in participants without depressive symptoms (HR 1.26, 95% CI 1.06–1.49; p = 0.01). Depressive symptoms were associated with dementia (HR 1.12, 95% CI 1.05–1.19), also without apathy symptoms (HR 1.16, 95% CI 1.03–1.31; p = 0.015), but not after full adjustment or after removing the GDS item on memory complaints.

Conclusions

Apathy and depressive symptoms are independently associated with incident dementia in community-dwelling older people. Subjective memory complaints may play an important role in the association between depressive symptoms and dementia. Our findings suggest apathy symptoms may be prodromal to dementia and might be used in general practice to identify individuals without cognitive impairment at increased risk of dementia.

[Clinical and neurovisualization characteristics of apathetic depression]

AIM

To study apathetic depression first diagnosed at late age and identify its relation to cognitive and social dysfunction as well as to morphological and functional changes in the brain.

MATERIAL AND METHODS

Thirty-two patients at the age above 60 years with newly diagnosed depressive episode and 15 healthy age-matched volunteers were included in the study. All patients were divided into two groups by the score on the Apathy scale (AS): >14 - depression with apathy (n=21), <14 - depression without apathy (n=11). Patients were examined using psychometric methods (HAMD, GDS, AS, SHAPS, SF-36, MoCA-test), neuroimaging (MRI scanner with a magnetic field strength of 1.5 Tesla - EXCEL ART Vantage Atlas-X, Toshiba, Japan) and statistical data analysis.

RESULTS AND CONCLUSION

Apathy component in clinical depression reflects a tendency towards the increase in depression severity and cognitive deterioration that results in the substantial lowering of quality of life and correlates with cerebrovascular changes, decrease in gray and white matter volume and mean cortical thickness of large hemispheres.

Structural correlates of apathy in Alzheimer's disease: a multimodal MRI study

OBJECTIVE

Apathy is one of the most frequent symptoms of dementia, whose underlying neurobiology is not well understood. The objective was to analyze the correlations of apathy and its dimensions with gray and white matter damage in the brain of patients with advanced Alzheimer's disease (AD).

METHODS

The setting of the study was at the Alzheimer Center Reina Sofía Foundation Research Unit. Participants include 37 nursing home patients with moderate to severe AD, 78.4% were women, and mean Standard Deviation (SD) age is 82.7 (5.8). Several measurements were taken: severe mini-mental state examination and Global Deterioration Scale for cognitive and functional status, Neuropsychiatric Inventory for behavioral problems, and Apathy In Dementia-Nursing Home Version Scale for apathy, including total score and subscores of emotional blunting, deficit of thinking, and cognitive inertia. 3T magnetic resonance imaging measures (voxel-based morphometry, fluid-attenuated inversion recovery, and diffusion tensor imaging) were also conducted.

RESULTS

Moderate levels of apathy (mean Apathy In Dementia-Nursing Home Version Scale: 31.1 ± 18.5) were found. Bilateral damage to the corpus callosum and internal capsule was associated with apathy severity (cluster size 2435, p < 0.0005, family-wise error [FWE]-corrected). A smaller and more anteriorly located region of the right internal capsule and corpus callosum was associated with higher emotional blunting (cluster size 334, p < 0.0005, FWE-corrected). Ischemic damage in the right periventricular frontal region was associated with higher deficit of thinking (cluster size 3805, p < 0.005, FWE-corrected).

CONCLUSIONS

Brain damage related to apathy may have different features in the advanced stages of AD and differs between the three apathy dimensions. Besides atrophy, brain connectivity and vascular lesions are relevant in the study of apathy, especially in the more severe stages of dementia. Further magnetic resonance imaging studies should include multimodal techniques. Copyright © 2016 John Wiley & Sons, Ltd.

Symptoms of Apathy Independently Predict Incident Frailty and Disability in Community-Dwelling Older Adults

OBJECTIVE

Although depressive symptoms are widely recognized as a predictor of functional decline among older adults, little is known about the predictive utility of apathy in this population. We prospectively examined apathy symptoms as predictors of incident slow gait, frailty, and disability among non-demented, community-dwelling older adults.

METHODS

We examined 2 independent prospective cohort studies-the LonGenity study (N = 625, 53% women, mean age = 75.2 years) and the Central Control of Mobility in Aging (CCMA) study (N = 312, 57% women, mean age = 76.4 years). Individuals were recruited from 2008 to 2014. Apathy was assessed using 3 items from the Geriatric Depression Scale. Slow gait was defined as 1 standard deviation or more below age- and sex-adjusted mean values, frailty was defined using the Cardiovascular Health Study criteria, and disability was assessed with a well-validated disability scale.

RESULTS

The prevalence of apathy was 20% in the LonGenity cohort and 26% in the CCMA cohort. The presence of apathy at baseline, independent of depressive symptoms (besides apathy), increased the risk of developing incident slow gait (hazard ratio [HR] = 2.10; 95% CI, 1.36-3.24; P = .001), frailty (HR = 2.86; 95% CI, 1.96-4.16; P < .001), and disability (HR = 3.43; 95% CI, 1.73-6.79; P < .001) in the pooled sample. These associations remained significant when accounting for demographics, medical illnesses, and cognitive function.

CONCLUSIONS

Apathy is associated with increased risk of developing slow gait, frailty, and disability, independent of other established risk factors, in non-demented older adults. Apathy should be screened for as a potentially preventable cause of functional decline in clinical psychiatric settings.

Validity of the three apathy items of the Geriatric Depression Scale (GDS-3A) in measuring apathy in older persons

OBJECTIVE

The Geriatric Depression Scale (GDS)-3A, a three-item subset of the GDS-15, is increasingly used as a measure for apathy in research settings to assess factors associating with this neuropsychiatric syndrome. We aimed to assess how accurately the GDS-3A discriminates between presence and absence of apathy in two populations of community-dwelling older persons, using the Apathy Scale as reference standard.

METHODS

Baseline data were used from 427 participants of the Discontinuation of Antihypertensive Treatment in Elderly people (DANTE) Study Leiden and 1118 participants of the PROactive Management Of Depression in the Elderly (PROMODE) Study, all ≥75 years and with available GDS-3A and Apathy Scale measurements. A cut-off score of ≥14 was used for presence of apathy according to the Apathy Scale. Areas under the receiver operating characteristic curve (AUC) were calculated. Based on the likelihood ratios for GDS-3A scores, a cut-off of ≥2 was used for presence of apathy according to the GDS-3A to calculate test characteristics.

RESULTS

The AUC was 0.68 (95% confidence interval 0.62-0.73) in the DANTE Study and 0.72 (0.67-0.77) in the PROMODE Study. In the DANTE Study sensitivity was 29.3% (21.4-38.1) and specificity was 88.5% (84.4-91.8), whereas in the PROMODE Study sensitivity was 32.8% (24.5-41.1) and specificity 92.6% (90.9-94.2). Stratification on population characteristics did not yield more favourable test characteristics.

CONCLUSION

The GDS-3A has low sensitivity and high specificity as a measure of apathy in two populations of older persons. Using the GDS-3A in research might yield estimates biassed towards the null in case of non-differential misclassification. Copyright © 2016 John Wiley & Sons, Ltd.

Longitudinal course of behavioural and psychological symptoms of dementia: systematic review

BACKGROUND

More information about the pattern of behavioural and psychological symptoms of dementia (BPSD) in the course of dementia is needed to inform patients and clinicians and to design future interventions.

AIMS

To determine the persistence and incidence of BPSD and their relation to cognitive function, in individuals with dementia or in cohorts investigated for dementia onset.

METHOD

A systematic literature review analysed the baseline prevalence, persistence and incidence of 11 symptoms. The review was conducted according to established guidelines with the exception that we could not exclude the possibilities of bias in the studies examined.

RESULTS

The 59 included studies showed considerable heterogeneity in their objectives and methods. The symptoms hyperactivity and apathy showed high persistence and incidence; depression and anxiety low or moderate persistence and moderate incidence; and psychotic symptoms low persistence with moderate or low incidence.

CONCLUSIONS

Despite heterogeneity across studies in terms of setting, focus and length of follow-up, there were clinically relevant differences in the longitudinal courses of different BPSD. Apathy was the only symptom with high baseline prevalence, persistence and incidence during the course of dementia.

Prefrontal Activity and Connectivity with the Basal Ganglia during Performance of Complex Cognitive Tasks Is Associated with Apathy in Healthy Subjects

Objective

Convergent evidence indicates that apathy affects cognitive behavior in different neurological and psychiatric conditions. Studies of clinical populations have also suggested the primary involvement of the prefrontal cortex and the basal ganglia in apathy. These brain regions are interconnected at both the structural and functional levels and are deeply involved in cognitive processes, such as working memory and attention. However, it is unclear how apathy modulates brain processing during cognition and whether such a modulation occurs in healthy young subjects. To address this issue, we investigated the link between apathy and prefrontal and basal ganglia function in healthy young individuals. We hypothesized that apathy may be related to sub-optimal activity and connectivity in these brain regions.

Methods

Three hundred eleven healthy subjects completed an apathy assessment using the Starkstein’s Apathy Scale and underwent fMRI during working memory and attentional performance tasks. Using an ROI approach, we investigated the association of apathy with activity and connectivity in the DLPFC and the basal ganglia.

Results

Apathy scores correlated positively with prefrontal activity and negatively with prefrontal-basal ganglia connectivity during both working memory and attention tasks. Furthermore, prefrontal activity was inversely related to attentional behavior.

Conclusions

These results suggest that in healthy young subjects, apathy is a trait associated with inefficient cognitive-related prefrontal activity, i.e., it increases the need for prefrontal resources to process cognitive stimuli. Furthermore, apathy may alter the functional relationship between the prefrontal cortex and the basal ganglia during cognition.

Frontal Cortical Atrophy as a Predictor of Poststroke Apathy

The aim of the study was to identify associations between the symptoms of poststroke apathy and sociodemographic, stroke-related (severity of stroke, degree of disability, and performance in activities of daily living), and radiological correlates. We determined the degree of cortical and subcortical brain atrophy, the severity of white matter and basal ganglia lesions on baseline computed tomography (CT) scans, and the localization of acute ischemia on control CT or magnetic resonance imaging scans in subacute stages of stroke. During follow-up examinations, in addition to the assessment of apathy symptoms using the Apathy Scale, we also evaluated symptoms of depression and anxiety using the Hospital Anxiety and Depression Scale. The study included 47 consecutive patients with acute ischemic stroke. Correlates significantly associated with apathy, determined at baseline and during follow-up, were entered into the "predictive" and "associative" multiple regression models, respectively. Frontal cortical atrophy and symptoms of depression were most strongly associated with poststroke apathy symptoms. In order to model an interrelation between both cortical atrophy and white matter lesions and aging, we supplemented 2 additional "predictive" models using interaction variables, whereby we confirmed the role of frontal cortical atrophy as a predictor of poststroke apathy also as a function of the increasing age of patients.

Multidimensional model of apathy in older adults using partial least squares--path modeling

Apathy defined as a mental state characterized by a lack of goal-directed behavior is prevalent and associated with poor functioning in older adults. The main objective of this study was to identify factors contributing to the distinct dimensions of apathy (cognitive, emotional, and behavioral) in older adults without dementia. One hundred and fifty participants (mean age, 80.42) completed self-rated questionnaires assessing apathy, emotional distress, anticipatory pleasure, motivational systems, physical functioning, quality of life, and cognitive functioning. Data were analyzed using partial least squares variance-based structural equation modeling in order to examine factors contributing to the three different dimensions of apathy in our sample. Overall, the different facets of apathy were associated with cognitive functioning, anticipatory pleasure, sensitivity to reward, and physical functioning, but the contribution of these different factors to the three dimensions of apathy differed significantly. More specifically, the impact of anticipatory pleasure and physical functioning was stronger for the cognitive than for emotional apathy. Conversely, the impact of sensibility to reward, although small, was slightly stronger on emotional apathy. Regarding behavioral apathy, again we found similar latent variables except for the cognitive functioning whose impact was not statistically significant. Our results highlight the need to take into account various mechanisms involved in the different facets of apathy in older adults without dementia, including not only cognitive factors but also motivational variables and aspects related to physical disability. Clinical implications are discussed.