The use of the French Dimensional Apathy Scale (f-DAS) to assess apathy in schizophrenia: Properties and profiles

Specific mechanisms underlying executive and emotional apathy: A phenotyping study

Apathy is a behavioral symptom prevalent both in neuropsychiatric pathologies and in the healthy population. However, the knowledge of the cognitive and neural mechanisms underlying apathy is still very limited, even if clinical and fMRI data support the existence of three forms of apathy (executive, emotional, initiative). These forms could be explained by the alteration of specific mechanisms. This present study's aim is to specify the cognitive and neuronal mechanisms of executive and emotional apathy. We used an EEG study conducted on 68 subjects comprising two groups of young people with specific executive or emotional phenotypes of apathy and one group with no apathy. Despite having symptom of apathy, participants were free of any neurological, metabolic, or psychiatric diagnoses and with high education. Two tasks were used: the DPX for cognitive control and the MID for motivation. Our results showed that distinct mechanisms underlie these two forms of apathy, and, for the first time, we specified these mechanisms. A deficit of the proactive control mode, reflected by a reduced probe-N2 amplitude in AY trials, underlies the executive form of apathy (p < .03), whereas liking motivational blunting, highlighted by a reduced LPP amplitude for financial loss, characterizes the emotional form (p < .04). The main limit of the results is that generalizability to the general population may be reduced since the apathetic samples were chosen for having a specific form of apathy. To conclude, better knowledge of these mechanisms informs new, more targeted treatments, both pharmacological and non-pharmacological, necessary for reducing the debilitating consequences of apathy.

Outcome of severe COVID-19: spotlight on fatigue, fatigability, multidomain complaints and pattern of cognitive deficits in a case series without prior brain dysfunction and without COVID-19-related stroke and/or cardiac arrest

BACKGROUND

Population-wide surveys and large-scale investigations highlighted the presence of cognitive deficits in the acute and postacute stages of severe COVID-19; a few studies documented their occurrence in cases without prior or COVID-19-related brain damage. The evolution of cognitive deficits in the latter population and their relationship to the post-COVID-19 fatigue syndrome are poorly understood.

CASE PRESENTATION

We report the outcome at 12 months after severe COVID-19 involving an intensive care unit stay and mechanical ventilation in six (five Caucasian and one Asian) patients (age range: 53-71 years, mean age 61.7 ± 6.5 years) without history of prior brain dysfunction and without stroke and/or cardiac arrest during or after COVID-19. All patients reported pervading mental and physical fatigue as well as numerous multidomain complaints, which impacted everyday life. Individual patients described mental fatigability, apathy, and/or anxiety. Standardized neuropsychological tests revealed isolated symptoms of cognitive dysfunction or performance at the lower limit of the norm in the attentional, executive, and/or working memory domains in four of the six patients. Somatic scales documented dyspnoea, muscle weakness, olfactory disorder, and/or minor sleep problems in some, but not all, patients.

CONCLUSION

Fatigue, fatigability, multidomain complaints, cognitive difficulties, or dysfunction, as well as isolated neurobehavioral and/or psychiatric and/or somatic symptoms, tend to occur in the aftermath of severe COVID-19 and persist at 12 months, even in the absence of prior and/or COVID-19-related brain damage. This clinical situation, which impacts everyday life, calls for a detailed investigation of patients' complaints, its neural underpinning, and an elaboration of specific rehabilitation programs.

Semiology and determinants of apathy across neurodegenerative motor disorders: A comparison between amyotrophic lateral sclerosis, Parkinson’s and Huntington’s disease

Background

The semiology and determinants of apathy are largely unknown across amyotrophic lateral sclerosis (ALS), Parkinson’s disease (PD), and Huntington’s disease (HD), due to both motor and non-motor confounders. This study thus aimed at (1) profiling apathy in ALS, PD, and HD and (2) exploring its clinical determinants.

Materials

Consecutive ALS (N = 99), PD (N = 73), and HD (N = 25) patients underwent a motor-free assessment of apathy (Dimensional Apathy Scale, DAS), global cognition, anxiety and depression. Function was assessed through disease-specific scales. The DAS was also completed by N = 101 healthy controls (HCs). Between-group comparisons on DAS scores were implemented by covarying for all applicable confounders. Predictive models on DAS scores were built through multiple, stepwise regressions.

Results

Parkinson’s disease and HD, but not ALS, patients were more apathetic than HCs—with HD patients also selectively showing lower initiation and poorer goal-directed planning than HCs. Higher apathetic features were detected in PD and HD as compared to ALS. Education was a protective factor against apathy in ALS. Anxiety was a risk factor for global apathy in ALS, HD, and to a lesser extent, in PD, whereas, protective only toward affective disintegration in PD and ALS. Cognitive inefficiency was a risk factor toward apathy in both PD and ALS. Depression was a risk factor for executive-related apathy in PD.

Discussion

This study provides unprecedented insights into the heterogeneous semiology and determinants of apathy across ALS, PD, and HD via the DAS, in turn informing clinical practice and research.