Can cognitive deficits facilitate differential diagnosis between at-risk mental state for psychosis and depressive disorders?

Staging's determinants in early intervention youth: a retrospective study

OBJECTIVES

Since 2019 our early intervention unit has assessed help-seekers, mainly referred by psychiatric departments, and we have conducted a descriptive retrospective study. Our objective was to identify clinical determinants associated to staging at assessment for our three groups: "no psychosis", "ultra-high risk" and "first episode psychosis".

METHODS

One hundred and thirteen participants (mean age 20.05±3.28) were enrolled, mainly referred by adult psychiatry (81.4%). We tested the association of each group with the following determinants: age, gender, family history of psychosis, referral (adolescent or adult psychiatry), cognitive, depressive complaint, cannabis active consumption, and current activity (scholar or employment).

RESULTS

Multivariate analyses showed significant association with depressive symptoms (P=0.019) but an absence of family history of psychosis (P=0.002) or current activity (P=0.09) for "no psychosis" group. "Ultra-high risk" was significantly correlated with a family history of psychosis (P=0.001) and adolescent psychiatry referral (P=0.044) but an absence of depressive complaint (P=0.04). As for "first episode psychosis", we found significant cognitive complaint (P=0.026), family history (P=0.024) and current activity (0.026).

CONCLUSIONS

As all our participants were seen in tertiary care, adolescent psychiatrists were more efficient in detecting a high-risk state. "No psychosis" help-seekers presented in fact mood issues, which have been confused with attenuated psychotic symptoms by their addressers, who have probably been misled by their absence of activity integration. High-risk and characterized psychotic episodes were logically correlated with family history. Surprisingly, "first episode psychosis" youth were currently integrated in scholarly or professional life despite an active cognitive complaint. Robust studies, especially prospective cohorts, are needed to test these associations.

Neurocognitive deficits in depression: a systematic review of cognitive impairment in the acute and remitted state

Previous research suggests a broad range of deficits in major depressive disorder. Our goal was to update the current assumptions and investigate the extent of cognitive impairment in depression in the acute and remitted state. A systematic review of the existing literature between 2009 and 2019 assessing the risk of bias within the included studies was performed. Of the 42 articles reviewed, an unclear risk of bias was shown overall. The risk of bias mainly concerned the sample selection, inadequate remedial measures, as well as the lack of blinding the assessors. In the acute phase, we found strong support for impairment in processing speed, learning, and memory. Follow-up studies and direct comparisons revealed less pronounced deficits in remission, however, deficits were still present in attention, learning and memory, and working memory. A positive correlation between the number of episodes and cognitive deficits as well as depression severity and cognitive deficits was reported. The results also demonstrate a resemblance between the cognitive profiles in bipolar disorder and depression. Comparisons of depression with schizophrenia led to unclear results, at times suggesting an overlap in cognitive performance. The main findings support the global deficit hypothesis and align with results from prior meta-analyses and reviews. Recommendations for future research are also presented.

Neuropsychological Performance Among Individuals at Clinical High-Risk for Psychosis vs Putatively Low-Risk Peers With Other Psychopathology: A Systematic Review and Meta-Analysis

BACKGROUND AND HYPOTHESIS

Youth at clinical high-risk (CHR) for psychosis present with neuropsychological impairments relative to healthy controls (HC), but whether these impairments are distinguishable from those seen among putatively lower risk peers with other psychopathology remains unknown. We hypothesized that any excess impairment among CHR cohorts beyond that seen in other clinical groups is minimal and accounted for by the proportion who transition to psychosis (CHR-T).

STUDY DESIGN

We performed a systematic review and meta-analysis of studies comparing cognitive performance among CHR youth to clinical comparators (CC) who either sought mental health services but did not meet CHR criteria or presented with verified nonpsychotic psychopathology.

STUDY RESULTS

Twenty-one studies were included representing nearly 4000 participants. Individuals at CHR showed substantial cognitive impairments relative to HC (eg, global cognition: g = -0.48 [-0.60, -0.34]), but minimal impairments relative to CC (eg, global cognition: g = -0.13 [-0.20, -0.06]). Any excess impairment among CHR was almost entirely attributable to CHR-T; impairment among youth at CHR without transition (CHR-NT) was typically indistinguishable from CC (eg, global cognition, CHR-T: g = -0.42 [-0.64, -0.19], CHR-NT: g = -0.09 [-0.18, 0.00]; processing speed, CHR-T: g = -0.59 [-0.82, -0.37], CHR-NT: g = -0.12 [-0.25, 0.07]; working memory, CHR-T: g = -0.42 [-0.62, -0.22], CHR-NT: g = -0.03 [-0.14, 0.08]).

CONCLUSIONS

Neurocognitive impairment in CHR cohorts should be interpreted cautiously when psychosis or even CHR status is the specific clinical syndrome of interest as these impairments most likely represent a transdiagnostic vs psychosis-specific vulnerability.

The EEG correlates and dangerous behavioral consequences of drowsy driving after a single night of mild sleep deprivation

OBJECTIVE

Here, we investigated the behavioral, cognitive, and electrophysiological impact of mild, acute sleep loss via simultaneously recorded behavioral and electrophysiological measures of vigilance during a "real-world", simulated driving task.

METHODS

Participants (N = 34) visited the lab for two testing days where their brain activity and vigilance were simultaneously recorded during a driving simulator task. The driving task lasted approximately 70 mins and consisted of tailgating the lead car at high speed, which braked randomly, requiring participants to react quickly to avoid crashing. The night before testing, participants either slept from 12am-9am (Normally Rested), or 1am-6am (Sleep Restriction).

RESULTS

After a single night of mild sleep restriction, sleepiness was increased, participants took longer to brake, missed more braking events, and crashed more often. Brain activity showed more intense alpha burst activity and significant changes in EEG spectral power frequencies related to arousal (e.g., delta, theta, alpha). Importantly, increases in amplitude and number of alpha bursts predicted delays in reaction time when braking.

CONCLUSIONS

The findings of this study suggest that a single night of mild sleep loss has significant, negative consequences on driving performance and vigilance, and a clear impact on the physiology of the brain in ways that reflect reduced arousal.

SIGNIFICANCE

Understanding neural and cognitive changes associated with sleep loss may lead to important advancements in identifying and preventing potentially dangerous sleep-related lapses in vigilance.

Estimation of Years Lived with Disability Using a Prevalence-Based Approach: Application to Major Psychiatric Disease in Korea

To help develop policies concerning the prevention of psychiatric disease in Korea, we reviewed the literature on this topic in different countries and used a prevalence-based approach to estimate the years lived with disability (YLDs) in Korean patients with major psychiatric diseases. We calculated YLDs by extracting data on the number of patients with mild, moderate, and severe cases of schizophrenia, bipolar disorder, and major depressive disorder, as classified by International Statistical Classification of Disease (ICD) codes. YLDs were highest for patients with major depressive disorder (1190.6; 73.9%), schizophrenia (303.3; 18.8%) and bipolar disorder (117.9; 7.3%). Men had higher YLDs for schizophrenia, 2502 (20-24 years); bipolar disorder, 477 (40-44 years); and major depressive disorder, 2034 (75-79 years). Women had higher YLDs for schizophrenia, 484 (45-49 years); bipolar disorder, 214 (≥80 years); and major depressive disorder, 3541 (75-79 years). The prevalence-based approach and severity distribution is useful for estimating long-term psychiatric disease burden and YLDs. However, YLD-estimation studies must compensate for the shortcomings of the ICD-10 by referencing the Diagnostic and Statistical Manual of Mental Disorders 5th edition, as well as updating the disability weight score according to disease severity.

EEG and behavioural correlates of mild sleep deprivation and vigilance

OBJECTIVE

The current study investigated the behavioral, cognitive, and electrophysiological impact of mild (only a few hours) and acute (one night) sleep loss via simultaneously recorded behavioural and physiological measures of vigilance.

METHODS

Participants (N = 23) came into the lab for two testing days where their brain activity and vigilance were recorded and assessed. The night before the testing session, participants either slept from 12am to 9am (Normally Rested), or from 1am to 6am (Sleep Restriction).

RESULTS

Vigilance was reduced and sleepiness was increased in the Sleep Restricted vs. Normally Rested condition, and this was exacerbated over the course of performing the vigilance task. As well, sleep restriction resulted in more intense alpha bursts. Lastly, EEG spectral power differed in Sleep Restricted vs. Normally Rested conditions as sleep onset progressed, particularly for frequencies reflecting arousal (e.g., delta, alpha, beta).

CONCLUSIONS

The findings of this study suggest that only one night of mild sleep loss significantly increases sleepiness and, importantly, reduces vigilance. In addition, this sleep loss has a clear impact on the physiology of the brain in ways that reflect reduced arousal.

SIGNIFICANCE

Understanding the neural correlates and cognitive processes associated with loss of sleep may lead to important advancements in identifying and preventing deleterious or potentially dangerous, sleep-related lapses in vigilance.

Neuropsychological profile of children and adolescents with psychosis risk syndrome: the CAPRIS study

Neuropsychological underperformance is well described in young adults at clinical high risk for psychosis, but the literature is scarce on the cognitive profile of at-risk children and adolescents. The aim of this study is to describe the neuropsychological profile of a child and adolescent sample of patients with psychosis risk syndrome (PRS) compared to healthy controls and to analyze associations between attenuated psychotic symptoms and cognitive impairment. Cross-sectional baseline data analysis from a longitudinal, naturalistic, case-control, two-site study is presented. Eighty-one help-seeking subjects with PRS and 39 healthy controls (HC) aged between 10 and 17 years of age were recruited. PRS was defined by: positive or negative attenuated symptoms, Brief Limited Intermittent Psychotic Symptoms (BLIPS), genetic risk (first- or second-degree relative), or schizotypal personality disorder plus impairment in functioning. A neuropsychological battery was administered to assess general intelligence, verbal and visual memory, visuospatial abilities, speed processing, attention, and executive functions. The PRS group showed lower general neuropsychological performance scores at a multivariate level and lower scores than controls in general intelligence and executive functions. Lower scores on executive function and poorer attention were associated with high scores of positive attenuated psychotic symptoms. No association with attenuated negative symptoms was found. This study provides evidence of cognitive impairment in PRS children and adolescents and shows a relationship between greater cognitive impairment in executive functions and attention tasks and severe attenuated positive symptoms. However, longitudinal studies are needed to clarify the nature of cognitive impairment as a possible vulnerability marker.

Cognitive functioning in ultra-high risk for psychosis individuals with and without depression: Secondary analysis of findings from the NEURAPRO randomized clinical trial

Neurocognitive impairments are well established in both ultra-high risk (UHR) for psychosis and major depressive disorder (MDD). Despite this understanding, investigation of neurocognitive deficits in UHR individuals with MDD and its association with MDD within this population, has been scarce. Hence, this study aimed to examine any differences in neurocognition at baseline between those with MDD at baseline and those with no history of MDD, as well as determine whether neurocognitive variables are significantly associated with meeting criteria for MDD at follow-up, while controlling for relevant clinical variables, within a UHR cohort. Data analysis was conducted on 207 participants whose baseline neurocognition was assessed using Brief Assessment of Cognition for Schizophrenia, as part of a trial of omega-3 fatty acids (NEURAPRO) for UHR individuals. While baseline MDD was the strongest predictor, poorer verbal memory and higher verbal fluency were significantly associated with MDD at 12 months (p = .04 and 0.026, respectively). Further, higher processing speed was significantly associated with MDD at medium-term follow-up (p = .047). These findings outline that neurocognitive skills were independently associated with meeting criteria for MDD at follow-up within UHR individuals, with novel findings of better verbal fluency and processing speed being linked to MDD outcomes. Hence, neurocognitive performance should be considered as a marker of risk for MDD outcomes and a target for management of MDD in UHR.

Can neuropsychological testing facilitate differential diagnosis between at-risk mental state (ARMS) for psychosis and adult attention-deficit/hyperactivity disorder (ADHD)?

Background:

Patients with an at-risk mental state (ARMS) for psychosis and patients with attention-deficit/hyperactivity disorder (ADHD) have many overlapping signs and symptoms and hence can be difficult to differentiate clinically. The aim of this study was to investigate whether the differential diagnosis between ARMS and adult ADHD could be improved by neuropsychological testing.

Methods:

168 ARMS patients, 123 adult ADHD patients and 109 healthy controls (HC) were recruited via specialized clinics of the University of Basel Psychiatric Hospital. Sustained attention and impulsivity were tested with the Continuous Performance Test, verbal learning and memory with the California Verbal Learning Test, and problem solving abilities with the Tower of Hanoi Task. Group differences in neuropsychological performance were analyzed using generalized linear models. Furthermore, to investigate whether adult ADHD and ARMS can be correctly classified based on the pattern of cognitive deficits, machine learning (i.e. random forests) was applied.

Results:

Compared to HC, both patient groups showed deficits in attention and impulsivity and verbal learning and memory. However, in adult ADHD patients the deficits were comparatively larger. Accordingly, a machine learning model predicted group membership based on the individual neurocognitive performance profile with good accuracy (AUC = 0.82).

Conclusions:

Our results are in line with current meta-analyses reporting that impairments in the domains of attention and verbal learning are of medium effect size in adult ADHD and of small effect size in ARMS patients and suggest that measures of these domains can be exploited to improve the differential diagnosis between adult ADHD and ARMS patients.

Sustained vigilance is negatively affected by mild and acute sleep loss reflected by reduced capacity for decision making, motor preparation, and execution

Study Objectives

The behavioral and cognitive consequences of severe sleep deprivation are well understood. Surprisingly, relatively little is known about the neural correlates of mild and acute sleep restriction on tasks that require sustained vigilance for prolonged periods of time during the day.

Methods and Results

Event-related potential (ERP) paradigms can reveal insight into the neural correlates underlying visual processing and behavioral responding that is impaired with reduced alertness, as a consequence of sleep loss. Here, we investigated the impact of reduced vigilance following at-home mild sleep restriction to better understand the associated behavioral consequences and changes in information processing revealed by ERPs. As expected, vigilance was reduced (e.g. increased lapses and response slowing) that increased over the course of the experiment in the "sleep restricted" (5 hr sleep) compared with the "sleep-extension" (9 hr sleep) condition. Corresponding to these lapses, we found decreased positivity of visually evoked potentials in the Sleep Restriction vs. Sleep Extension condition emerging from 316 to 449 ms, maximal over parietal/occipital cortex. We also investigated electrophysiological signs of motor-related processing by comparing lateralized readiness potentials (LRPs) and found reduced positivity of LRPs in the Sleep Restriction vs. Sleep Extension condition at 70-40 ms before, and 115-158 ms after a response was made.

Conclusions

These results suggest that even a single night of mild sleep restriction can negatively affect vigilance, reflected by reduced processing capacity for decision making, and dulls motor preparation and execution.

The Critical Need for Help-Seeking Controls in Clinical High-Risk Research

Despite rapidly growing knowledge of the clinical high-risk (CHR) state for psychosis, the vast majority of case-control studies have relied on healthy volunteers as a reference point for drawing inferences about the CHR construct. Researchers have long recognized that results generated from this design are limited by significant interpretive concerns, yet little attention has been given to how these concerns affect the growing field of CHR research. We argue that overreliance on healthy controls in CHR research threatens the validity of inferences concerning group differences, hinders advances in understanding the development of psychosis, and limits clinical progress. We suggest that the combined use of healthy and help-seeking (i.e., psychiatric) controls is a necessary step for the next generation of CHR research. We then evaluate methods for help-seeking control studies, identify the available CHR studies that have used such designs, discuss select findings in this literature, and offer recommendations for research.

Comparison of the neurocognitive profiles of individuals with elevated psychotic or depressive symptoms

AIM

Neurocognitive deficits are pervasive and enduring features of severe mental illness that appear before the onset of clinical symptoms and contribute to functional disability. However, it remains unclear how individuals who display warning signs for psychotic or mood disorders compare on their neurocognitive profiles since previous studies have separately examined neurocognition in both groups. Therefore, the purpose of this study was to directly compare performance on a range of neurocognitive tasks in individuals with emerging psychotic or mood symptoms.

METHODS

Participants were drawn from a database of individuals who completed a comprehensive assessment at a university-based assessment centre. We examined 3 groups: individuals who endorsed elevated psychotic symptoms (EPS; n = 64), individuals who endorsed elevated depressive symptoms (EDS; n = 58), or non-clinical comparisons (NCC; n = 57) without any elevated psychiatric symptoms or diagnoses.

RESULTS

EPS participants performed worse than NCC and EDS groups on verbal comprehension, working memory and cognitive flexibility, and worse than NCC, but not EDS, on perceptual reasoning. There were no significant differences between groups on processing speed, verbal fluency and set-shifting. EDS performed worse than both EPS and NCC groups on psychomotor speed. Dimensionally, poorer cognitive functioning was more strongly related to EPS than depressive symptoms.

CONCLUSIONS

These findings highlight the distinct yet overlapping neurocognitive profiles of both groups with emerging psychiatric symptoms, and suggest that, despite having no formal diagnosis, individuals with EPS exhibit observable cognitive impairment and may still benefit from interventions within academic and workplace contexts.

Early cognitive basic symptoms are accompanied by neurocognitive impairment in patients with an 'at-risk mental state' for psychosis

AIM

Patients with an increased risk for psychosis ('at-risk mental state' (ARMS)) present various neurocognitive deficits. Not least because of differences in identifying the ARMS, results of previous studies are inconsistent. In most studies ARMS-patients are classified by the experience of attenuated psychotic symptoms (APS) and/or brief limited intermittent psychotic symptoms (BLIPS). Few studies additionally assessed cognitive basic symptoms (BS). A comprehensive assessment in the very early stage of the ARMS is missing.

METHODS

In the present study we characterized ARMS-patients for cognitive BS (ARMS-BS), APS and BLIPS (ARMS-A/B) according to the Early Recognition Inventory based on IRAOS (ERIraos). Furthermore, we assessed neurocognitive deficits using the MATRICS consensus cognitive battery for schizophrenia with a primary hypothesis regarding working memory performance. Groups of 38 ARMS-patients and 38 healthy controls were matched for age, gender, education and premorbid verbal intelligence.

RESULTS

Between-group comparisons revealed significant poorer working memory performance in addition to lower verbal learning and problem solving, slower processing speed and lower global neurocognitive functioning in ARMS-patients as compared to controls. ARMS-BS did not differ from ARMS-A/B.

CONCLUSIONS

These results underscore the presence of cognitive limitations in patients only presenting with cognitive BS. Knowledge of these early cognitive deviations supports the inclusion of early ARMS-stages into a comprehensive concept of the psychosis risk state. Therapeutic interventions already applied at this stage might prevent deterioration of constraints. Longitudinal and interventional studies investigating the interaction of cognitive BS and neurocognitive as well as metacognitive deficits are warranted.

Cognition in at-risk mental states for psychosis

RATIONALE

The devastating nature of schizophrenia and treatment limitations have triggered a search for early detection methods to enable interventions to be implemented as soon as the first signs and symptoms appear. In this effort, several studies have investigated the cognitive functions in individuals regarded as being in at-risk mental states (ARMS) for psychosis.

OBJECTIVE

Our aim was to make a systematic review of the literature regarding basic and social cognition in individuals in ARMS following the guidelines of the PRISMA statement.

RESULTS

In general, the results of the 49 articles included in the review show that individuals in ARMS have pervasive cognitive deficits that seem to be greater in individuals who later convert to psychosis.

CONCLUSIONS

Cognitive impairment can be detected in individuals considered to be in ARMS according to current classifications and may serve as a risk marker for psychotic conversion; however, the lack of standardized criteria to define ARMS and of homogeneous cognitive assessment methods hamper the generalization of findings from different studies.