Psychometric and factorial validity of the International Adjustment Disorder Questionnaire (IADQ) in an Italian sample: A validation and prevalence estimate study.

INTRODUCTION: Adjustment disorder (AjD) is a is a maladaptive emotional or behavioural reaction to a stressful event or change in a person's life. Compared to other previously validated tools, the International Adjustment Disorder Questionnaire (IADQ) stands out as one of the most reliable and handy one for AjD. Since no homologous instrument exists now, in this study, we aimed to validate an Italian version of the IADQ. METHODS: Twenty-one thousand two hundred and six subjects (80.4% females) during the initial stages of the SARS-CoV-2 pandemic were recruited. We conducted a confirmatory factor analysis (CFA), testing two latent models, a monofactorial and a bifactorial one. Concurrent validity by correlating the total and the two factors' scores with measures of depression, anxiety and post-traumatic stress was then estimated. We finally estimated the rates of AjD among the population, and a binary logistic regression was conducted to analyse the predictors of such disorder. RESULTS: CFA showed a bifactorial validity, with both excellent incremental and comparative fit indices. The IADQ scores correlated strongly with symptoms of depression, anxiety and stress. In the Italian sample, the prevalence of probable AjD was 8.23%. Female gender, being engaged, widowed and having COVID-19-related stressors resulted as significant independent risk factors for AjD. CONCLUSIONS: IADQ is an easy-to-use, brief and psychometrically sound self-report measure for AjD. Thus, it may be considered a reliable tool for both research and clinical settings. To the best of our knowledge, our study reported for the first time the prevalence of AjD during COVID-19 pandemic.

Spatiotemporal EEG dynamics of the sleep onset process in preadolescence.

BACKGROUND: During preadolescence the sleep electroencephalography undergoes massive qualitative and quantitative modifications. Despite these relevant age-related peculiarities, the specific EEG pattern of the wake-sleep transition in preadolescence has not been exhaustively described. METHODS: The aim of the present study is to characterize regional and temporal electrophysiological features of the sleep onset (SO) process in a group of 23 preadolescents (9-14 years) and to compare the topographical pattern of slow wave activity and delta/beta ratio of preadolescents with the EEG pattern of young adults. RESULTS: Results showed in preadolescence the same dynamics known for adults, but with peculiarities in the delta and beta activity, likely associated with developmental cerebral modifications: the delta power showed a widespread increase during the SO with central maxima, and the lower bins of the beta activity showed a power increase after SO. Compared to adults, preadolescents during the SO exhibited higher delta power only in the slowest bins of the band: before SO slow delta activity was higher in prefrontal, frontal and occipital areas in preadolescents, and, after SO the younger group had higher slow delta activity in occipital areas. In preadolescents delta/beta ratio was higher in more posterior areas both before and after the wake-sleep transition and, after SO, preadolescents showed also a lower delta/beta ratio in frontal areas, compared to adults. CONCLUSION: Results point to a general higher homeostatic drive for the developing areas, consistently with plastic-related maturational modifications, that physiologically occur during preadolescence.

Psychotic-like experiences associated with ICD-11 PTSD and cPTSD in a cohort of Italian late adolescents.

INTRODUCTION: Post-traumatic stress disorder (PTSD) and complex PTSD (cPTSD) are two sibling stress-related disorders. Evidence suggests a worse clinical picture associated with cPTSD in terms of comorbidities and outcomes. However, little is known about the association between cPTSD and psychotic-like experiences (PLEs). In this study, we aim to explore differences in PLEs in a sample of 1010 late adolescents with PTSD and cPTSD symptoms. METHODS: A sample of 1010 late-adolescents and young adults attending the last year of high school was selected. PLEs were assessed using the 16-items Prodromal Questionnaire (PQ-16), PTSD and cPTSD were assessed using the International Trauma Questionnaire (ITQ). RESULTS: 999 (501 males, 50.15% and 498 females, 49.85%) subjects had complete data on the selected variables. Of these, 91 (9.11%) and 40 (4.00%) screened positive for PTSD and cPTSD, respectively. Mean number of PLEs endorsed in subjects with PTSD, cPTSD and control groups were 7.02 (sd=2.99), 8.17 (sd=3.70) and 4.49 (sd=2.93), respectively. Mean PQ-16 distress score was 5.08 (sd=4.6) in subjects not endorsing PTSD/cPTSD, 10.11 (sd=6.17) in PTSD and 14.51 (sd=9.1) in cPTSD subjects. A linear regression analysis revealed a significant association between PTSD/cPTSD and PLEs scores (respectively, b=4.91 [3.73, 6.10] and b=10.05 [8.40, 11.70]). Such associations were reduced after adjustment for depression, anxiety and dissociation. DISCUSSION AND CONCLUSIONS: Our results find higher rates of PLEs in late adolescents screening positive for cPTSD and PTSD compared to negative subjects. Furthermore, cPTSD could be more specifically associated with distressing PLEs. These findings add to the vast literature of a worse psychopathological picture associated with cPTSD compared to PTSD, emphasizing the need for a separation between PTSD and cPTSD in terms of diagnosis and possibly treatment.

The association between traumatic experiences and substance and behavioral addictions in late adolescence: A role for PTSD and cPTSD as potential mediators.

BACKGROUND & AIM: Traumatic experiences (TEs) are a risk factor for behavioral and substance addictions (SBAs). However, the role of post-traumatic stress disorder (PTSD) and complex PTSD (cPTSD) deserves further elucidation. The present study assesses the association between different types of TEs on cannabis, alcohol, gambling, and problematic internet use in late adolescents. Furthermore, this study aims at evaluating the role of PTSD and cPTSD as potential mediators. METHODS: An observational cross-sectional study was conducted on one thousand ten late adolescents (510 males, 498 females; age: mean = 18.7, SD = 0.65). Data regarding intentional (iTEs) and unintentional TEs (uTEs), cannabis, alcohol, gambling and problematic use of the internet (PIU), PTSD, and cPTSD were collected. Association between TEs, SBAs, and PTSD/cPTSD symptoms were explored by means of logistic regressions. Mediation was assessed using a path analysis. RESULTS: uTEs were associated with cannabis use (OR = 1.34 [1.13,1.59]) and alcohol use (OR = 1.21 [1.10,1.35]), iTEs were associated with cannabis use (OR = 1.15 [1.06,1.25]), alcohol use (OR = 1.08 [1.02,1.13]), and PIU (OR = 1.17 [1.10,1.24]). PTSD was associated with alcohol use (OR = 1.59 [1.03,2.46]) and PIU (OR = 1.92 [1.18,3.13]). cPTSD was associated with cannabis use (OR = 3.54 [1.56,8.04]) and PIU (OR = 5.13 [2.71,9.70]). cPTSD mediated 58.75% of the total effect of iTEs on cannabis. Regarding PIU, PTSD mediated 68.18% of the effect of uTEs; the effect of iTEs on PIU was mediated by 65.5% via cPTSD and 34.45% via PTSD. CONCLUSION: cPTSD and SBAs show a complex pattern of association. A thorough assessment of stress-related conditions, including cPTSD, is of pivotal importance in treating SBAs.

Sleep-Related Declarative Memory Consolidation in Children and Adolescents with Developmental Dyslexia.

Sleep has a crucial role in memory processes, and maturational changes in sleep electrophysiology are involved in cognitive development. Albeit both sleep and memory alterations have been observed in Developmental Dyslexia (DD), their relation in this population has been scarcely investigated, particularly concerning topographical aspects. The study aimed to compare sleep topography and associated sleep-related declarative memory consolidation in participants with DD and normal readers (NR). Eleven participants with DD and 18 NR (9-14 years old) underwent a whole-night polysomnography. They were administered a word pair task before and after sleep to assess for declarative memory consolidation. Memory performance and sleep features (macro and microstructural) were compared between the groups, and the intercorrelations between consolidation rate and sleep measures were assessed. DD showed a deeper worsening in memory after sleep compared to NR and reduced slow spindles in occipito-parietal and left fronto-central areas. Our results suggest specific alterations in local sleep EEG (i.e., sleep spindles) and in sleep-dependent memory consolidation processes in DD. We highlight the importance of a topographical approach, which might shed light on potential alteration in regional cortical oscillation dynamics in DD. The latter might represent a target for therapeutic interventions aimed at enhancing cognitive functioning in DD.

Sleep EEG oscillations in neurodevelopmental disorders without intellectual disabilities.

Neurodevelopmental disorders (NDDs) are often characterised by sleep problems, and recent evidence indicates alterations of the sleep electroencephalographic (EEG) oscillations in these patients. Sleep microstructure plays a crucial role in cognitive functioning and brain maturation. In this view, modifications in sleep EEG oscillations in NDDs could further impair the cognitive maturation process in these patients. We provide an overview of sleep microstructure alterations observed in three NDDs without intellectual disabilities (attention-deficit/hyperactivity disorder, high-functioning autism/Asperger syndrome and developmental dyslexia) and their relationships with the disorders' phenomenology. For each NDD, we discuss empirical evidence of altered EEG oscillations, and we consider their interaction with patients' cognitive and behavioural functioning, with the aim to elucidate their functional meaning. We highlight the limits of the present literature and propose possible future directions while underlining the clinical relevance of the research in this field. Beyond confirming the importance of sleep management in atypically developing children, the review findings suggest that sleep EEG oscillations in NDDs could become a target for specific clinical intervention.

The heritability of the human K-complex: a twin study.

Sleep electroencephalogram (EEG) has a trait-like nature. Several findings highlighted the heritability of spectral power in specific frequency ranges and sleep spindles during nonrapid eye movement (NREM) sleep. However, a genetic influence on the K-complex (KC), one of the electrophysiological hallmarks of NREM sleep, has never been assessed. Here, we investigated the heritability of the KC detected during NREM stage 2 comparing 10 monozygotic (MZ) and 10 dizygotic (DZ) twin pairs. Genetic variance analysis (GVA) and intraclass correlation coefficients (ICCs) were performed to assess the genetic effect and within-pair similarity for KC density, amplitude, and for the area under the curve (AUC) of the KC average waveform at Fz, Cz, and Pz scalp locations. Moreover, cluster analysis was performed on the KC average waveform profile. We observed a significant genetic effect on KC AUC at Cz and Pz, and on amplitude at Pz. Within-pair similarity (ICCs) was always significant for MZ twins except for KC density at Fz, whereas DZ twins always exhibited ICCs below the significance threshold, with the exception of density at Pz. The largest differences in within-pair similarity between MZ and DZ groups were observed again for AUC at Cz and Pz. MZ pairs accurately clustered for the KC average waveform with a higher frequency (successful clustering rate for MZ pairs: Fz = 60%; Cz = 80%; Pz = 90%) compared with DZ pairs (successful clustering rate for DZ pairs: Fz = 10%; Cz = 10%; Pz = none). Our results suggest the existence of a genetic influence on the human KC, particularly related to its morphology and maximally observable in central and parietal locations.

Advances in Understanding the Relationship between Sleep and Attention Deficit-Hyperactivity Disorder (ADHD).

Starting from the consolidated relationship between sleep and cognition, we reviewed the available literature on the association between Attention Deficit-Hyperactivity Disorder (ADHD) and sleep. This review analyzes the macrostructural and microstructural sleep features, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria (PRISMA). We included the polysomnographic studies published in the last 15 years. The results of macrostructural parameters are mixed. Almost half of the 18 selected investigations did not find differences between sleep architecture of children with ADHD and controls. Five studies observed that children with ADHD show a longer Rapid Eye Movement (REM) sleep duration than controls. Eight studies included microstructural measures. Remarkable alterations in sleep microstructure of ADHD are related to slow wave activity (SWA) and theta oscillations, respectively, during Non-REM (NREM) and REM sleep. Specifically, some studies found higher SWA in the ADHD group than controls. Similarly, higher theta activity appears to be detrimental for memory performance and inhibitory control in ADHD. These patterns could be interpreted as a maturational delay in ADHD. Also, the increased amount of these activities would be consistent with the hypothesis that the poor sleep could imply a chronic sleep deprivation in children with ADHD, which in turn could affect their cognitive functioning.

Not only a Problem of Fatigue and Sleepiness: Changes in Psychomotor Performance in Italian Nurses across 8-h Rapidly Rotating Shifts.

Although many studies have detailed the consequences of shift work in nurses concerning health, fatigue, sleepiness, or medical errors, no study has been carried out trying to disentangle the contribution of sleepiness and fatigue associated to shift work from the attentional performance. The aim of this pilot study is (A) to investigate the effects of an 8-h rapidly rotating shift on fatigue and sleepiness among staff nurses and (B) how these factors affect their psychomotor performance. Fourteen nurses were selected for a within-subject cross-sectional study according to this sequence of shifts: morning⁻afternoon⁻night, which were compared as function of tiredness, sleepiness, and performance at the Psychomotor Vigilance Task (PVT). Subsequently, a within-subject Analysis of Covariance (ANCOVA) evaluated if the observed differences between shifts persist when the contribution of sleepiness is controlled. Our results clearly indicate that night shifts are associated with significant greater sleepiness and tiredness, and worsened performance at the PVT. As hypothesized, ANCOVA showed that these differences disappear when the contribution of sleepiness is controlled. Results point to a lower psychomotor performance in night compared to day shifts that depends on sleepiness. Hence, interventions to minimize the consequences of the night shift should consider a reduction of sleepiness.

In Search of Sleep Biomarkers of Alzheimer's Disease: K-Complexes Do Not Discriminate between Patients with Mild Cognitive Impairment and Healthy Controls.

The K-complex (KC) is one of the hallmarks of Non-Rapid Eye Movement (NREM) sleep. Recent observations point to a drastic decrease of spontaneous KCs in Alzheimer's disease (AD). However, no study has investigated when, in the development of AD, this phenomenon starts. The assessment of KC density in mild cognitive impairment (MCI), a clinical condition considered a possible transitional stage between normal cognitive function and probable AD, is still lacking. The aim of the present study was to compare KC density in AD/MCI patients and healthy controls (HCs), also assessing the relationship between KC density and cognitive decline. Twenty amnesic MCI patients underwent a polysomnographic recording of a nocturnal sleep. Their data were compared to those of previously recorded 20 HCs and 20 AD patients. KCs during stage 2 NREM sleep were visually identified and KC densities of the three groups were compared. AD patients showed a significant KC density decrease compared with MCI patients and HCs, while no differences were observed between MCI patients and HCs. KC density was positively correlated with Mini-Mental State Examination (MMSE) scores. Our results point to the existence of an alteration of KC density only in a full-blown phase of AD, which was not observable in the early stage of the pathology (MCI), but linked with cognitive deterioration.

The Fall of Sleep K-Complex in Alzheimer Disease.

Although a slowing of electroencephalographic (EEG) activity during wakefulness and -to some extent- sleep of Alzheimer disease (AD) patients (i.e., increased slow-frequency activity) was documented, recent findings in healthy elderly show a decreased 0.6-1 Hz slow wave activity (SWA) during NREM, which was associated to ß-amyloid deposition and impaired hippocampal memory consolidation. We hypothesize that the apparent contradiction may be explained by the partial overlap between 0.6-1 Hz EEG activity and K-Complex (KC). According to this view, we studied both frontal KCs and SWA in 20 AD patients and 20 healthy age-matched controls (HC) during nightly sleep, under the hypothesis that KCs better discriminate patients from healthy elderly than ≤1 Hz SWA. A drastic decrease of KC density during stage 2 NREM was found in AD compared to HC. Patients show more than 40% reduction of the KC density, allowing a correct classification of 80%. On the other hand, ≤1 Hz SWA of AD patients is slightly (not significantly) higher in most cortical areas compared to HC. Although no significant changes of ≤1 Hz SWA are detectable over frontal areas in AD, KC density decreases over the same location, and its decrease is related to the cognitive decline.