Daytime sleepiness in insomnia: Are we focusing on what truly matters?

Insomnia, the most prevalent sleep disorder, is commonly associated with other mental and somatic disorders, making it a significant health concern. It is characterized by nighttime symptoms and daytime dysfunction, with sleepiness being a potential criterion for the latter. Sleepiness is a normal physiological state that is typically experienced near usual bedtime, in normal circumstances. In insomnia, it seems somewhat logical the idea that there is significant daytime sleepiness. However, the topic has been the subject of various discussions in sleep medicine, with studies yielding contradictory and inconsistent results. In this article, we aim to critically examine daytime sleepiness in individuals with insomnia disorder and propose an alternative approach to addressing it, both in clinical practice and research settings. It is crucial to further investigate the role of daytime sleepiness in insomnia, particularly by focusing on sleepiness perception as a more relevant dimension to explore in majority of patients. It is plausible that certain insomnia phenotypes are objectively sleepy during the day, but more studies are necessary, particularly with well-defined clinical samples. The implications of assessing sleepiness perception in insomnia for clinical practice are discussed, and new avenues for research are suggested.

Insomnia Severity Index: A reliability generalisation meta-analysis.

The aim of the current study was to conduct a reliability generalisation (RG) meta-analysis of Cronbach's alpha for the Insomnia Severity Index (ISI). A systematic search of three databases (PubMed, Scopus, and Web of Science) from inception to 12 March 2021 was performed. Publications that reported Cronbach's alpha for the total ISI score were included. Only psychometric-focussed studies were considered. Meta-analysis was carried out using a random-effects model to derive a pooled estimate of Cronbach's alphas. The number of participants in the included publications ranged from 25 to 12,056, with 33 studies (42 estimates) comprising internal consistency coefficients, and a combined sample size of N = 29,688. The age range of the included publications was from 13.4 to 74.3 years. Data extraction implied 33 publications out of 706 found through the database search. Cronbach's alphas ranged from 0.65 to 0.92. The majority of the reported coefficients were ≥0.7 and presented a low risk of bias (n = 32). The pooled alpha coefficient was 0.83 (IC [0.81-0.85]; SE = 0.009) with high heterogeneity among the included publications (I2  = 97%). Subgroup analyses including moderators such as continent, setting, risk of bias, and age did not affect significantly the overall result. In general, the cumulative estimate of Cronbach's alpha for the ISI is good. However, this finding should be interpreted with caution since there is a high heterogeneity level and some of the studies might not have checked the assumptions underlying Cronbach's alphas.

Psychometric Properties of the Sleep Locus of Control (SLOC) Scale in a Portuguese Sample.

Over the past few decades, research has suggested that cognitive variables play a key role in sleep disorders, particularly, in insomnia. The SLOC (Sleep Locus of Control Scale) evaluates the sleep locus of control, which is associated with the degree to which an individual attributes her/his experiences of sleep to chance or internal causes. The aim of this study was to develop the first translation and adaptation of the SLOC into the European Portuguese, as well as to analyze its psychometric properties. In this study, it was recruited a sample of 2029 Portuguese Higher Education students, aged ≥ 18 years, where approximately 75% of the sample were women and 25% men. The results showed that the SLOC had acceptable internal consistency value (α = .64), considering that it is a measure with a reduced number of items. As in the original study, a principal component analysis with varimax rotation identified two components. A parallel analysis was also conducted, identifying two factors. The correlation between the two subscales "internal sleep locus of control" and "chance sleep locus of control" was positive albeit of low magnitude (r = .15). Through the analysis carried out, it was also observed that individuals with "insomnia", relative to those without, had a more chance sleep locus of control. Overall, these findings show similarities with the original study. The SLOC seems to be a useful psychological assessment measure to be used in clinical and research settings.

Profiles of Subjective Daytime Sleepiness through Cluster Analysis.

Sleepiness propensity and sleepiness perception are two relevant dimensions of the general multidimensional sleepiness construct. In the current study, the aim was to identify eventual homogeneous subgroups when sleepiness propensity and sleepiness perception measures are combined. Data from 678 undergraduate students (aged 17 to 24 years) from a medical school were analyzed. A Two-Step Cluster Analysis was performed taken into consideration sleepiness propensity and sleepiness perception measures as clustering variables. Four different clusters were identified. Additionally, the two groups comprising higher levels of sleepiness perception (i.e., "high perception, low propensity" and "high subjective daytime sleepiness" clusters) had the most compromised results in some of the sleep-related variables examined - sleep needs, sleep latency, sleep quality, sleep sufficiency, self-reported insomnia, sleep reactivity to stress, and cognitive arousal - and in some of non-sleep related variables, such as neuroticism and affect. As to non-sleep variables, those groups reported higher scores in neuroticism, arousability, self-reported mental health and affective states. The identification of distinct groups concerning self-reported sleepiness may bring new avenues for research and understanding of the specific and differential role of sleepiness and its dimensions in sleep health and sleep disturbances, in particular, insomnia disorder.

Differences in Early Maladaptive Schemas between Young Adults Displaying Poor Versus Good Sleep Quality.

Research on the connection between sleep-related problems and Early Maladaptive Schemas (EMS) is scarce. The aim of the current study was to investigate a potential link between EMSs and poor sleep quality. Participants (n = 249) were selected from a larger sample of 1253 European Portuguese college students who completed the BaSIQS and the YSQ-S3. The major inclusion criteria for the selected participants were high versus low scores on the BaSIQS (poor versus good sleep quality). Students with poor sleep quality had significantly higher levels of Abandonment/ Instability, Mistrust/Abuse, Social Isolation/Alienation, Vulnerability to Harm or Illness, Entitlement/Grandiosity, Self-Sacrifice, and Negativity/Pessimism. These data suggest that EMSs are associated with poor sleep quality. However, additional studies are necessary to better understand this relationship.

BaSIQS - basic scale on insomnia complaints and quality of sleep: reliability, norms, validity, and accuracy studies, based on clinical and community samples.

This research focused on the Basic Scale on Insomnia Symptoms and Quality of Sleep (BaSIQS), formerly validated in undergraduates using the Pittsburgh Sleep Quality Index (PSQI), and aimed to expand internal consistency analysis, examine thoroughly its validity, and determine its clinical accuracy. Considering objective and subjective measures, recruiting non-clinical and clinical samples, this research implemented a comprehensive approach to examine convergent and discriminant validity, confirmatory factor analyses, and the BaSIQS sensitivity and specificity. The BaSIQS was filled out along with the Insomnia Severity Index (ISI), questions on sleep-wake schedules, Composite Scale of Morningness (CSM) and Brief Symptom Inventory-18 (BSI-18) by 1198 adults, 18-64 years old, plus another 30 who wore actimeters, recruited in community settings. A clinical group of 30 chronic insomnia disorder patients also participated. Cronbach alpha coefficient was 0.80. A two-factor structure was confirmed. The association between BaSIQS and ISI was large, whereas actigraphy correlations were medium or small. Medium to non-significant correlations were found concerning conceptually different self-report measures. Comparing the clinic and control groups, the former showed poorer sleep, with a large effect size. Receiver operating characteristic analysis revealed an area under curve = 0.9, and an optimal cut-off score >15. In conclusion, results on reliability, validity, and accuracy provide support to the utility of the BaSIQS both in community and clinical settings, for research and practical purposes.

Insomnia Disorder and Brain's Default-Mode Network.

PURPOSE OF REVIEW: Insomnia disorder (ID) is a prevalent sleep disorder that significantly compromises the physical and mental health of individuals. This article reviews novel approaches in the study of brain networks and impaired function in ID through the application of modern neuroimaging techniques such as functional magnetic resonance imaging (fMRI). RECENT FINDINGS: The default-mode network (DMN) is presumed to be correlated with self-referential information processing, and it appears to be altered or unbalanced in insomnia. A growing body of evidence suggests the lack of deactivation of brain regions comprising the DMN when insomnia patients are at rest. Moreover, core areas of the DMN demonstrate greater activation in insomnia patients when compared to healthy controls in self-referential related tasks. Despite the few studies on the topic, underpinning the correlation between abnormal DMN activity and ID deserves further attention in the future. Implications for therapeutics are briefly outlined.

Portuguese Version of the Arousal Predisposition Scale: Preliminary Evidence for a Two-Factor Structure in a Nonclinical Sample.

It is known that there is significant variability in arousal levels of the individuals. The Arousal Predisposition Scale (APS) is a questionnaire intended to measure individual differences in arousability. In the current work, our aim was to present the initial psychometric properties of the Portuguese version of the APS. Three hundred forty-five undergraduate medical students from both genders were enrolled. All participants filled out a set of questionnaires-which contained the APS-at the end of their lectures and out of the evaluation period. The APS showed good internal consistency (α = .85) and discriminated individuals with extreme scores. Further, in general, the scale discriminated as well both genders pertaining to the individual items and total score. In terms of scale structure, two related factors were extracted (F1 = emotional reactivity and F2 = trait anxiety). Significant associations among APS and other sleep and psychological self-report variables were also observed. The APS seems to be a reliable and valid instrument to assess self-reported physiological arousability, at least in a sample of young adults. The two-factor composition will require more studies to be replicated in similar groups and, particularly, in clinical samples.

Associations between sleep quality and domains of quality of life in a non-clinical sample: results from higher education students.

OBJECTIVE: The association between sleep quality and quality of life (QoL) in clinical samples diagnosed with sleep disorders, mental disorders, or other medical conditions has been widely investigated. However, few studies focused on this relationship in samples of mostly young and healthy adults. This study analyzed the associations between sleep quality and several dimensions of QoL in higher education students and examined whether or not sleep quality would significantly predict QoL after statistically controlling for psychopathological symptoms. DESIGN: Observational and transversal. SETTING: Non-clinical; higher education. PARTICIPANTS: A sample of 324 college students, aged 17 to 47 years (M=20.89±2.85) were enrolled. MEASUREMENTS: European Portuguese versions of the Pittsburgh Sleep Quality Index (PSQI), the WHOQOL-Bref to measure QoL, and the Brief Symptom Inventory (BSI) to measure psychopathological symptoms. RESULTS: All PSQI components were significantly associated with general QoL and the psychological and physical QoL domains. The subjective sleep quality and daytime dysfunction PSQI components were consistently associated with all WHOQOL-Bref domains and general QoL. Hierarchical regression analyses further showed that the PSQI components as a whole, and in particular subjective sleep quality, added significant contributions to the general QoL facet and to the psychological, physical, and environmental QoL domains, after controlling for psychopathological symptoms. CONCLUSIONS: Several components of sleep quality and different facets/domains of QoL are associated in higher education students, particularly subjective sleep quality, which remains a significant predictor of most aspects of QoL, regardless of the presence of psychopathological symptoms.

Circadian preferences in young adults: Psychometric properties and factor structure of the Portuguese version of the Preferences Scale (PS-6).

Morningness is a trait-like variable which has been extensively studied within chronobiology. Despite the number of existing measures to assess morningness, there is a need for brief instruments that are psychometrically sound to be used in applied settings. Accordingly, the modified version of the Preferences Scale (PS-6) comprises six items and was reported to have adequate reliability and satisfactory validity indicators. In this article, the psychometric properties of the Portuguese version of the PS-6 are reported. A total of 700 students attending medical school were recruited, and this sample was randomly divided into two groups. In the first group (n = 352), we assessed the internal consistency calculations and conducted a principal component analysis of the posited structure. In the second group (n = 348), we conducted a confirmatory factor analysis (CFA) using structural equation modeling. Overall, the results indicated that the PS-6 has adequate reliability (α = .75) and is constituted by two components: (I) preferred cognitive activities timings and (II) preferred sleeping-eating timings, respectively. In conclusion, the Portuguese version of the PS seems suitable for use in research and applied settings such as shift work schedules management. However, the applicability of the PS-6 in other samples and further validity indicators should be both investigated. The use of actigraphy and biological measures should also be collected to enhance the robustness of the PS-6.

Sleep-wake patterns reported by parents in hyperactive children diagnosed according to ICD-10, as compared to paired controls.

This study aimed primarily to compare the parent-reported sleep of children with ICD-10 hyperkinetic disorder (HKD) versus community children. Thirty children aged 5-13 years (83.3% boys) diagnosed with HKD by their child and adolescent psychiatrists took part in this study, plus 30 community children, matched for sex, age, and school year. Compared to the controls, the HKD children showed significantly later bedtimes, stronger bedtime resistance, longer sleep latency, shorter sleep; more frequent behaviors and symptoms concerning falling asleep into parents bed, needing something special to initiate sleep, nightmares, sleep talking, sleep bruxism, fear from darkness, bedwetting, and, most notably, loud snoring (26.7%); they also tended to show higher daytime somnolence. Attention deficit/hyperactivity disorder (ADHD)/HKD children may thus have more sleep-related problems than typically developing children. Alternatively, our results may reflect misdiagnoses; thus, special attention should be directed to comorbidity and differential diagnosis issues between sleep disturbances and ADHD/HKD.

Is positive affect in pregnancy protective of postpartum depression?

OBJECTIVE: To investigate the predictive/protective role of negative affect/positive affect in late pregnancy on the outcome of postpartum depression. METHODS: A total of 491 pregnant women participated in the study. The participants were asked to fill out a series of questionnaires, which included the Profile of Mood States, the Beck Depression Inventory-II, psychosocial variables and socio-demographic characteristics and were asked to participate in a psychiatric interview. After delivery, 272 mothers participated again in the study and filled out a similar series of questionnaires. RESULTS: Negative affect was associated with more intense depressive symptomatology, more self-perceived stress, lower self-reported social support, lower quality of life and perception of having a more difficult infant. By contrast, positive affect was negatively associated with these variables. Negative affect in late pregnancy increased the likelihood of experiencing postpartum depression (DSM-IV/OR = 2.1, 95%CI = 1.3-3.4, p = .003; ICD-10/OR = 2.1, 95%CI = 1.5-3.0, p < .001), while positive affect increased the odds of not having this condition (DSM-IV/OR = 2.0, 95%CI = 1.5-2.7, p = .042). CONCLUSION: In pregnancy, negative affect was a predictor of postpartum depression, whereas positive affect showed a protective role. Future studies are required to explore whether psychotherapeutic strategies focusing on decreasing negative affect and enhancing positive affect in the last trimester of pregnancy can reduce the risk of postpartum depression.

Is positive affect in pregnancy protective of postpartum depression?

OBJECTIVE: To investigate the predictive/protective role of negative affect/positive affect in late pregnancy on the outcome of postpartum depression. METHODS: A total of 491 pregnant women participated in the study. The participants were asked to fill out a series of questionnaires, which included the Profile of Mood States, the Beck Depression Inventory-II, psychosocial variables and socio-demographic characteristics and were asked to participate in a psychiatric interview. After delivery, 272 mothers participated again in the study and filled out a similar series of questionnaires. RESULTS: Negative affect was associated with more intense depressive symptomatology, more self-perceived stress, lower self-reported social support, lower quality of life and perception of having a more difficult infant. By contrast, positive affect was negatively associated with these variables. Negative affect in late pregnancy increased the likelihood of experiencing postpartum depression (DSM-IV/OR = 2.1, 95%CI = 1.3-3.4, p = .003; ICD-10/OR = 2.1, 95%CI = 1.5-3.0, p < .001), while positive affect increased the odds of not having this condition (DSM-IV/OR = 2.0, 95%CI = 1.5-2.7, p = .042). CONCLUSION: In pregnancy, negative affect was a predictor of postpartum depression, whereas positive affect showed a protective role. Future studies are required to explore whether psychotherapeutic strategies focusing on decreasing negative affect and enhancing positive affect in the last trimester of pregnancy can reduce the risk of postpartum depression.

Sleep and academic performance in undergraduates: a multi-measure, multi-predictor approach.

The present study examined the associations of sleep patterns with multiple measures of academic achievement of undergraduate university students and tested whether sleep variables emerged as significant predictors of subsequent academic performance when other potential predictors, such as class attendance, time devoted to study, and substance use are considered. A sample of 1654 (55% female) full-time undergraduates 17 to 25 yrs of age responded to a self-response questionnaire on sleep, academics, lifestyle, and well-being that was administered at the middle of the semester. In addition to self-reported measures of academic performance, a final grade for each student was collected at the end of the semester. Univariate analyses found that sleep phase, morningness/eveningness preference, sleep deprivation, sleep quality, and sleep irregularity were significantly associated with at least two academic performance measures. Among 15 potential predictors, stepwise multiple regression analysis identified 5 significant predictors of end-of-semester marks: previous academic achievement, class attendance, sufficient sleep, night outings, and sleep quality (R(2)=0.14 and adjusted R(2)=0.14, F(5, 1234)= 40.99, p < .0001). Associations between academic achievement and the remaining sleep variables as well as the academic, well-being, and lifestyle variables lost significance in stepwise regression. Together with class attendance, night outings, and previous academic achievement, self-reported sleep quality and self-reported frequency of sufficient sleep were among the main predictors of academic performance, adding an independent and significant contribution, regardless of academic variables and lifestyles of the students.

Is insomnia in late pregnancy a risk factor for postpartum depression/depressive symptomatology?

The aim of the present work was to investigate if insomnia in late pregnancy is a risk factor for postpartum depressive symptomatology/postpartum depression (PPD). 581 women in their last trimester of pregnancy answered questions/questionnaires about lifetime history of insomnia, current sleep perception, current mood and depressive symptomatology. They were interviewed with the Portuguese version of the Diagnostic Interview for Genetic Studies. After delivery 382 (65.7%) mothers participated again in the study. Insomnia in pregnancy was not a risk factor for PPD (DSM-IV or ICD-10) but was a significant predictor of postpartum depressive symptomatology. Negative Affect (NA) was a significant predictor of postpartum depressive symptomatology. Women with higher NA were 4.6 (CI95%=1.69-12.74) and 5.3 times (CI95%=2.26-12.58) more likely of experiencing PPD (DSM-IV/ICD-10, respectively) than women with lower NA. Lifetime Depression was a significant predictor of postpartum depressive symptomatology and ICD-10/PPD (OR=2.6; CI95%=1.16-4.38). Positive Affect (PA) showed to be a protective factor for postpartum depressive symptomatology and DSM-IV/PPD (OR=1.5; CI95%=1.20-2.33). Controlling NA, PA and Lifetime Depression, insomnia lost its predictive role, suggesting these variables might work as mediators. Associations between insomnia, NA, PA and Lifetime Depression should be assessed in pregnancy. This might help to preventively target NA, enhance PA and reduce the likelihood of experiencing postpartum depressive symptomatology.

The postpartum depression screening scale: is it valid to screen for antenatal depression?

The purpose of the study was to analyse for the first time the validity of a slightly modified version of the Portuguese Postpartum Depression Screening Scale (PDSS), to be used as a screening instrument for antenatal depression. Specifically, the aims were to analyse its psychometric properties, to determine PDSS cutoff points and associated conditional probabilities to screen for depression according to DSM-IV and ICD-10 criteria and to compare its screening performance with that of the Beck Depression Inventory-II (BDI-II). Five hundred and three pregnant women in the third trimester of pregnancy completed both questionnaires and were interviewed face-to-face with the Portuguese version of the Diagnostic Interview for Genetic Studies. The Portuguese version of the Operational Criteria Checklist for Psychotic Illness was used to obtain DSM-IV and ICD-10 diagnoses of depression, our gold standards for caseness. PDSS reliability and validity were very good and comparable to those obtained in the postpartum validation studies developed in Portugal and in other countries, showing satisfactory sensitivity and specificity combinations (≅80%). Compared with BDI-II, it has the advantage of being more specific for the motherhood context. Although developed for postpartum depression, PDSS is accurate to screen for antenatal depression, and it could be very useful for clinical and epidemiologic purposes.

The Portuguese version of the postpartum depression screening scale.

The aim of the present study was to analyse whether the Portuguese version of the Postpartum Depression Screening Scale (PDSS) was a valid instrument for screening postpartum depression. For this purpose the following objectives were delineated: (1) to analyse PDSS psychometric properties; (2) to determine PDSS cut-off points and associated conditional probabilities for screening depression according to DSM-IV and ICD-10 criteria; and (3) to compare the performance of PDSS with the Beck Depression Inventory-II (BDI-II) in screening for postpartum depression. Four hundred eighty-six 3-months-postpartum women completed both questionnaires and were interviewed with the Portuguese version of Diagnostic Interview for Genetic Studies (DIGS). The Portuguese version of the operational criteria checklist for psychotic illness (OPCRIT) was used to obtain DSM-IV and ICD-10 diagnoses of depression, our gold standards for caseness. PDSS reliability and validity were very good and equivalent to those reported in other versions, including the original. PDSS was an accurate screening instrument for postpartum depression, showing satisfactory combination of sensitivity and specificity (>80%). Compared to BDI-II it has the advantage of being more specific for the motherhood context. PDSS could be very useful for clinical and epidemiological purposes.

Longitudinal study on perfectionism and sleep disturbance.

AIM: To examine if perfectionism predicts self-reported sleep disturbances over time. METHODS: The Hewitt-Flett Perfectionism Scale was used to assess self-oriented, socially-prescribed (SPP) and other-oriented perfectionism. Sleep disturbance was evaluated with two items: difficulty in falling asleep and waking up many times during the night. Out of 870 students who participated at baseline, 592 and 305 completed the same measures 1 year (T1) and 2 years later (T2), respectively. RESULTS: Subjects who reported insomnia at baseline, T1 and T2 (persistent insomnia) had significantly higher scores of baseline SPP (T1 M = 51.5, SD = 15.8; T2 M = 55.0, SD = 19.0) than subjects reporting, in all stages of the study, never/rarely having had sleep problems (T1 M = 41.9, SD = 11.4; T2 M = 42.2, SD = 12.3, P<0.001 in both cases). Regression analyses showed that baseline SPP was the only significant positive predictor of difficulties in falling asleep at T1 and T2 (T1 partial R=0.187; T2 partial R=0.196, P<0.001) and of difficulties maintaining sleep (T1 partial R=0.116; T2 partial R=0.244, P<0.001). CONCLUSION: SPP was found to be the most reliable predictor of sleep disturbances over time, which constitutes a new important finding.

Perfectionism dimensions in pregnancy--a study in Portuguese women.

Pregnancy is essentially a physiological event, but neuroendocrinal and psychosocial changes are also important components of this experience. In this context, perceived stress may be enhanced by the activation of certain personality traits, like perfectionism, which in turn may be associated with more psychological distress (PD). The aim of this study was to investigate if perfectionism could be associated with more negative emotional outcomes (PD) in the transition to motherhood and to look at which of the perfectionism dimensions these consequences are specifically linked. The sample comprises 421 pregnant women (mean = 29.8, SD = 4.48 years) who completed measures of perfectionism and mood symptoms. A two-factor model with self-oriented perfectionism (SOP) and socially prescribed perfectionism (SPP) dimensions and a three-factor model with SOP, SPP-others' high standards and SPP-conditional acceptance (CA) factors were explored. Correlations and linear regressions were calculated between perfectionism factors and mood variables. Results showed that higher levels of SPP factors were associated with increased anxiety, depression, anger, fatigue and confusion, with decreased vigour and with more severe depressive symptoms. Our results, in contrast with those from the study of Campbell and DiPaula (2002, In: Flett G, Hewitt P (eds) Perfectionism. Theory, research, and practice. American Psychological Association, Washington, pp 181-198), did not confirm a preferential association between SPP-CA and PD, revealing that both components of SPP were associated with PD.

Perfectionism and sleep disturbance.

The main purpose of the present research was to explore gender-related associations between sleep disturbance and perfectionism dimensions in a large sample of undergraduate students. Perfectionism dimensions have been assessed using the Portuguese version of the Multidimensional Perfectionism Scale (Hewitt and Flett, 1991 , J Pers Soc Psychol 60:456; Soares et al., 2003 , Rev Port Psicossom 5:46) and sleep disturbance with two items concerning difficulties initiating sleep and difficulties maintaining sleep. A total of 1163 undergraduate students of both genders between 17 and 25 years of age completed the scale. Results from correlational and categorial analyses indicated that socially prescribed perfectionism was the only dimension associated with sleep disturbance in undergraduate students of both genders. Males with the highest levels of socially prescribed perfectionism were approximately twice more likely to report sleep disturbances than those with less socially prescribed perfectionism. Similar results were found within the female sample. Implications for future research and clinical practice are discussed.