Insomnia as a mediating therapeutic target for depressive symptoms: A sub‐analysis of participant data from two large randomized controlled trials of a digital sleep intervention

Insomnia predicts the onset of depression, commonly co‐presents with depression and often persists following depression remission. However, these conditions can be challenging to treat concurrently using depression‐specific therapies. Cognitive behavioural therapy for insomnia may be an appropriate treatment to improve both insomnia and depressive symptoms. We examined the effects of a fully‐automated digital cognitive behavioural therapy intervention for insomnia (Sleepio) on insomnia and depressive symptoms, and the mediating role of sleep improvement on depressive symptoms in participants from two randomized controlled trials of digital cognitive behavioural therapy for insomnia. We also explored potential moderators of intervention effects. All participants met criteria for probable insomnia disorder and had clinically significant depressive symptomatology (PHQ‐9 ≥ 10; n = 3,352). Individuals allocated to treatment in both trials were provided access to digital cognitive behavioural therapy. Digital cognitive behavioural therapy significantly improved insomnia (p < .001; g = 0.76) and depressive symptoms (p < .001; g = 0.48) at post‐intervention (weeks 8–10), and increased the odds (OR = 2.9; 95% CI = 2.34, 3.65) of clinically significant improvement in depressive symptoms (PHQ‐9 < 10). Improvements in insomnia symptoms at mid‐intervention mediated 87% of the effects on depressive symptoms at post‐intervention. No variables moderated effectiveness outcomes, suggesting generalizability of these findings. Our results suggest that effects of digital cognitive behavioural therapy for insomnia extend to depressive symptoms in those with clinically significant depressive symptomatology. Insomnia may, therefore, be an important therapeutic target to assist management of depressive symptoms.     

A Meta‐Analysis of Personalized Treatment Goals in Psychotherapy: A Preliminary Report and Call for More Studies

The aim of this study was to explore the hypothesis that psychotherapy has larger effect sizes for personalized treatment goals than for symptom checklists. We conducted a meta‐analysis of clinical trials that measured treatment success in terms of both symptom checklists and personalized treatment goals. Our search of the literature yielded 12 studies that met our inclusion criteria. Effect sizes were substantially larger for personalized treatment goals (ES = .86, p < .0001) than for symptom checklists (ES = .32, p = .003). The magnitude of this difference was significant (p < .05). Our results suggest that psychotherapy is perhaps more effective in helping patients with individual goals than reducing scores on broad measures of symptoms. Estimates of the effectiveness of psychotherapy that are based on symptom checklists perhaps underestimate the true benefit of psychotherapy. We discuss the implications for research and clinical practice.     

Dose‐dependent effects of continuous positive airway pressure for sleep apnea on weight or metabolic function: Individual patient‐level clinical trial meta‐analysis

Therapeutic‐continuous positive airway pressure seems to increase weight compared with placebo‐continuous positive airway pressure. It is not known whether weight gain with therapeutic‐continuous positive airway pressure dose is dependent or whether it causes metabolic dysfunction. Data synthesis of three randomised placebo‐continuous positive airway pressure‐controlled trials (2–3 months) was performed to test whether there is a dose‐dependent effect of continuous positive airway pressure on weight. Fasting glucose, insulin, insulin resistance (homeostatic model assessment), lipids and visceral abdominal fat were also tested to determine any effect on metabolic function. Mixed‐model analysis of variance was used to quantify these effects. One‐hundred and twenty‐eight patients were analysed. Overall there was a small increase in weight with therapeutic‐continuous positive airway pressure use compared with placebo‐continuous positive airway pressure (difference: 1.17 kg; 0.37–1.97, p = 0.005), which was greater with high‐use therapeutic‐continuous positive airway pressure compared with high‐use placebo‐continuous positive airway pressure (1.45 kg; 0.10–2.80, p = 0.04). Continuous positive airway pressure use as a continuous variable was also significantly associated with weight change in continuous positive airway pressure users (0.30 kg hr^?1 night^?1; 0.04–0.56, p = 0.001), but not in placebo users (0.04 kg hr^?1 night^?1; ?0.22 to 0.26, p = 0.76). Neither therapeutic‐continuous positive airway pressure nor the dose of therapeutic‐continuous positive airway pressure caused any changes to metabolic outcomes. The weight gain effects of medium‐term therapeutic‐continuous positive airway pressure appear modest and are not accompanied by any adverse metabolic effects.     

Insomnia symptoms and non‐suicidal self‐injury in adolescence: understanding temporal relations and mechanisms

We propose a theoretical model of insomnia symptoms and non‐suicidal self‐injury (NSSI) that posits bidirectional linkages. We hypothesised that heightened depressive symptoms and impulsivity that result from insomnia increase NSSI. We also posit that the shame associated with NSSI triggers repetitive negative thinking, in turn increasing insomnia. Using three longitudinal waves of questionnaire data collected annually from a sample of Swedish adolescents (n = 1,457; M_age = 13.2, SD = 0.43; 52.7% boys), we assessed the mediating role of depressive symptoms, impulsivity, rumination, and worry on the link between insomnia and NSSI. After controlling for depressive symptoms, we found that insomnia was related to increases in NSSI from the second to the third time point (ß₂₃ = 0.09, p = .01). NSSI was consistently related to increased insomnia (ß₁₂ = 0.09, p = .01; ß₂₃ = 0.11, p < .001). In addition, depressive symptoms (ß_ind = 0.01, p = .02), but not impulsivity (ß_ind = 0.01, p = .09), mediated the path from insomnia to increased NSSI. Neither worry (ß_ind = 0.00, p = .59) nor rumination (ß_ind = 0.00, p = .96) mediated the link between NSSI and increased insomnia. We conclude that NSSI and insomnia maintain each other over time. Thus, screening adolescents for insomnia symptoms may help identify those at risk of NSSI. Although depression seems to explain why insomnia is a risk factor for NSSI, further studies should investigate why NSSI plays a role in the maintenance of insomnia. This understanding will lay the foundation for intervention.     

Anxiety in the workplace: A comprehensive occupational health evaluation of anxiety disorder in public school teachers

The purpose of the study was to systematically assess demographic, occupational, and psychosocial factors associated with Anxiety Disorder in public school teachers. A sample of 3,361 public school teachers was given an online questionnaire, including questions about demographic, occupational, and psychosocial factors. Anxiety Disorder was based on the Patient Health Questionnaire. Univariate analyses and a hierarchical logistic regression were used to determine the key demographic, occupational, and psychosocial factors associated with Anxiety Disorder. Individuals with Anxiety Disorder were significantly more likely to report absenteeism and higher intent to quit (p < .001). The hierarchical logistic regression showed that the factors most associated with the Anxiety Disorder included being Hispanic (p < .01), taught fewer years (p < .05), teaching elementary school (p < .01), higher job involvement (p < .01), higher perceived stress (p < .01), lower physical quality of life (p < .01), major depression (p < .001), and somatization disorder (p < .01). The results from this study identify specific demographic, occupational, and psychosocial factors associated with the presence of anxiety disorder in public school teachers. Future research should examine how implementing changes in the workplace may improve occupational factors such as job control, satisfaction, absenteeism, and intent to quit, which, in turn, may be associated with a reduction in the presence of anxiety disorders.     

Usefulness of cardiac parasympathetic index in CPAP‐treated patients with obstructive sleep apnea: A preliminary study

Cardiac autonomic indexes, including cardiac parasympathetic index and cardiac sympathetic index, have been reported to accurately identify patients with sleep disorders such as obstructive sleep apnea. Our study aimed to assess cardiac autonomic indexes in patients with obstructive sleep apnea before and during a single full‐night continuous positive airway pressure therapy using a combined approach. Our simultaneous heart rate variability‐polysomnographic study included 16 never‐treated obstructive sleep apnea patients. Two patients dropped out. Patients underwent combined recordings in two consecutive days, at baseline and during a single full‐night of acute continuous positive airway pressure treatment. We calculated cardiac parasympathetic index and cardiac sympathetic index as night/day ratio for high‐frequency and low‐frequency heart rate variability spectral components, respectively. Continuous positive airway pressure treatment significantly reduced cardiac autonomic indexes values in comparison with baseline values (cardiac parasympathetic index: p < .0001; cardiac sympathetic index: p = .001). After acute continuous positive airway pressure treatment, the percentage of decrease of cardiac parasympathetic index was greater than that of cardiac sympathetic index (51.02 ± 15.72 versus 34.64 ± 26.93). A positive statistical correlation was also found between decrease of cardiac parasympathetic index and decrease of apnea–hypopnea index after continuous positive airway pressure (p < .001). This study improves the knowledge on cardiac autonomic modulation during acute continuous positive airway pressure therapy in obstructive sleep apnea. Our results demonstrate that both autonomic indexes decreased significantly after a single‐night of acute continuous positive airway pressure therapy. Cardiac parasympathetic index more than cardiac sympathetic index was related to decrease of apnea–hypopnea index after continuous positive airway pressure therapy, thus representing a potential help in everyday clinical practice.     

Self‐administered acupressure for insomnia disorder: a pilot randomized controlled trial

Self‐administered acupressure has potential as a low‐cost alternative treatment for insomnia. To evaluate the short‐term effects of self‐administered acupressure for alleviating insomnia, a pilot randomized controlled trial was conducted. Thirty‐one subjects (mean age: 53.2 years; 77.4% female) with insomnia disorder were recruited from a community. The participants were randomized to receive two lessons on either self‐administered acupressure or sleep hygiene education. The subjects in the self‐administered acupressure group (n = 15) were taught to practise self‐administered acupressure daily for 4 weeks. The subjects in the comparison group (n = 16) were advised to follow sleep hygiene education. The primary outcome was the Insomnia Severity Index (ISI). Other measures included a sleep diary, Hospital Anxiety and Depression Scale and Short‐form Six‐Dimension. The subjects in the self‐administered acupressure group had a significantly lower ISI score than the subjects in the sleep hygiene education group at week 8 (effect size = 0.56, P = 0.03). However, this observed group difference did not reach a statistically significant level after Bonferroni correction. With regard to the secondary outcomes, moderate between‐group effect sizes were observed in sleep onset latency and wake after sleep onset based on the sleep diary, although the differences were not significant. The adherence to self‐administered acupressure practice was satisfactory, with 92.3% of the subjects who completed the lessons still practising acupressure at week 8. In conclusion, self‐administered acupressure taught in a short training course may be a feasible approach to improve insomnia. Further fully powered confirmatory trials are warranted.     

Validation of a French version of the Sleep Condition Indicator: a clinical screening tool for insomnia disorder according to DSM‐5 criteria

Insomnia disorder is frequent in the population, yet there is no French screening instrument available that is based on the updated DSM‐5 criteria. We evaluated the validity and reliability of the French version of an insomnia screening instrument based on DSM‐5 criteria, the Sleep Condition Indicator, in a population‐based sample of adults. A total of 366 community‐dwelling participants completed a face‐to‐face clinical interview to determine insomnia disorder against DSM‐5 criteria and several questionnaires including the French Sleep Condition Indicator version. Three‐hundred and twenty‐nine participants completed the Sleep Condition Indicator again after 1 month. Statistical analyses were performed to determine the reliability, construct validity, divergent validity and temporal stability of the French translation of the Sleep Condition Indicator. In addition, an explanatory factor analysis was performed to assess the underlying structure. The internal consistency (α = 0.87) and temporal stability (r = 0.86, P < 0.001) of the French Sleep Condition Indicator were high. When using the previously defined cut‐off value of ≤ 16, the area under the receiver operating characteristic curve was 0.93 with a sensitivity of 95% and a specificity of 75%. Additionally, good construct and divergent validity were demonstrated. The factor analyses showed a two‐factor structure with a focus on sleep and daytime effects. The French version of the Sleep Condition Indicator demonstrates satisfactory psychometric properties while being a useful instrument in detecting cases of insomnia disorder, consistent with features of DSM‐5, in the general population.     

IL‐17A[G197G]—Association between NOx and gestational age in a South African birth cohort

Interleukin (IL‐)17A, plays a role in pathogenic defence, but is implicated in chronic inflammatory diseases, and has recently been associated with variable pregnancy outcomes. We investigated the role of maternal IL‐17‐[G197A]‐specific effects of third‐trimester IL‐17 mRNA expression, NO_x exposure levels and other variables on gestational age, in the Mother and Child in the Environment (MACE) birth cohort in South Africa. A total of 327 participants were genotyped for IL‐17‐[G197A] by polymerase chain reaction restriction‐fragment length polymorphism (PCR‐RFLP). Quantitative real‐time PCR was used to quantitate IL‐17‐mRNA expression in whole blood. Multivariate linear regression analysis, stratified by IL‐17‐[G197A] genotype, was used to test for effects of NO_x, IL17A/GAPDH, haemoglobin, body mass index, HIV‐1 positivity, maternal education and income level on gestational age. Lower expression was associated with the IL‐17‐GG versus GA in the cohort and HIV‐1‐negative group (p = .0007, p = .0058), while no difference was observed in the HIV‐1 positives. Elevated IL‐17A expression was observed in the high NO_x exposure groups, within IL‐17[G197G] (p = .0004). IL‐17[G197G] was associated with PTB (p < .0001), and the PTB group had lower IL‐17A expression compared to the full‐term group (p = .0002). IL‐17 expression was associated with an increase in gestational age (p = .038), and NO_x was associated with a decrease in gestational age in the IL‐17[G197G] model (p = .046).     

A dimensional examination of eating disorder symptoms in relation to cognitive processing: An event‐related potentials study

Identifying neurocognitive mechanisms involved in individuals experiencing eating disorder (ED) symptoms may be important for preventing EDs and improving rates of recovery. The present pilot study assessed how cognitive functioning may be associated with ED symptoms in college students (N = 41). Cognitive functioning was examined using electroencephalography during an auditory response inhibition task to measure the P3 component of event‐related potentials. Multiple regression analysis revealed that longer P3 latencies in the frontal region of the cortex were significantly and linearly associated with greater ED symptoms F(3, 37) = 13.62, p < .001, R² = 0.525, Adj. R² = 0.486. These pilot findings build upon prior work in clinical samples in that they indicate that functional brain differences are observable across a wide span of ED symptoms, not just in those with diagnosed ED. The present findings provide support for further exploration of changes in P3 latencies among individuals with ED symptoms to enhance our understanding of neural mechanisms that may pertain to the dimensional aspects of disordered eating attitudes and behaviors.     

Different cytokine production and toll‐like receptor expression induced by heat‐killed invasive and carrier strains of Neisseria meningitidis

Neisseria meningitidis may cause severe invasive disease. The carriage state of the pathogen is common, and the reasons underlying why the infection becomes invasive are not fully understood. The aim of this study was to compare the differences between invasive and carrier strains in the activation of innate immunity. The monocyte expression of TLR2, TLR4, CD14, and HLA‐DR, cytokine production, and the granulocyte oxidative burst were analyzed after in vitro stimulation by heat‐killed invasive (n = 14) and carrier (n = 9) strains of N. meningitidis. The expression of the cell surface markers in monocytes, the oxidative burst, and cytokine concentrations were measured using flow cytometry. Carrier strains stimulated a higher production of inflammatory cytokines and oxidative burst in granulocytes than invasive strains (all p < 0.001), whereas invasive strains significantly up‐regulated TLR2, TLR4 (p < 0.001), and CD14 (p < 0.01) expression on monocytes. Conversely, the monocyte expression of HLA‐DR was higher after the stimulation by carrier strains (p < 0.05) in comparison to invasive strains. The LPS inhibitor polymyxin B abolished the differences between the strains. Our findings indicate different immunostimulatory potencies of invasive strains of N. meningitidis compared with carrier strains.     

NREM‐related parasomnias in Machado–Joseph disease: clinical and polysomnographic evaluation

Spinocerebellar ataxias (SCA) are autosomal dominant neurodegenerative disorders that affect the cerebellum and its connections, and have a marked clinical and genetic variability. Machado–Joseph disease (MJD) or spinocerebellar ataxia type 3 (SCA3)—MJD/SCA3—is the most common SCA worldwide. MJD/SCA3 is characterized classically by progressive ataxia and variable other motor and non‐motor symptoms. Sleep disorders are common, and include rapid eye movement (REM) sleep behaviour disorder (RBD), restless legs syndrome (RLS), insomnia, excessive daytime sleepiness, excessive fragmentary myoclonus and sleep apnea. This study aims to focus upon determining the presence or not of non‐REM (NREM)‐related parasomnias in MJD/SCA 3, using data from polysomnography (PSG) and clinical evaluation. Forty‐seven patients with clinical and genetic diagnosis of MJD/SCA3 and 47 control subjects were evaluated clinically and by polysomnography. MJD/SCA3 patients had a higher frequency of arousals from slow wave sleep (P < 0.001), parasomnia complaints (confusional arousal/sleep terrors, P = 0.001; RBD, P < 0.001; and nightmares, P < 0.001), REM sleep without atonia (P < 0.001), periodic limb movements of sleep index (PLMSi) (P < 0.001), percentage of N3 sleep (P < 0.001) and percentage of N1 sleep (P < 0.001). These data show that NREM‐related parasomnias must be included in the spectrum of sleep disorders in MJD/SCA3 patients.     

Profiles of sleep changes during the COVID‐19 pandemic: Demographic,behavioural and psychological factors

This study aimed to evaluate changes in sleep during the COVID‐19 outbreak, and used data‐driven approaches to identify distinct profiles of changes in sleep‐related behaviours. Demographic, behavioural and psychological factors associated with sleep changes were also investigated. An online population survey assessing sleep and mental health was distributed between 3 April and 24 June 2020. Retrospective questions were used to estimate temporal changes from before to during the outbreak. In 5,525 Canadian respondents (67.1% females, 16–95 years old: Mean ± SD = 55.6 ± 16.3 years), wake‐up times were significantly delayed relative to pre‐outbreak estimates (p < .001,  = 0.04). Occurrences of clinically meaningful sleep difficulties significantly increased from 36.0% before the outbreak to 50.5% during the outbreak (all p < .001, g ≥ 0.27). Three subgroups with distinct profiles of changes in sleep behaviours were identified: “Reduced Time in Bed”, “Delayed Sleep” and “Extended Time in Bed”. The “Reduced Time in Bed” and “Delayed Sleep” subgroups had more adverse sleep outcomes and psychological changes during the outbreak. The emergence of new sleep difficulties was independently associated with female sex, chronic illnesses, being employed, family responsibilities, earlier wake‐up times, higher stress levels, as well as heavier alcohol use and television exposure. The heterogeneity of sleep changes in response to the pandemic highlights the need for tailored interventions to address sleep problems.     

Gabapentin acutely increases the apnea–hypopnea index in older men: data from a randomized,double‐blind,placebo‐controlled study

Although drugs with sedative properties may increase the risk of airway collapse during sleep, their acute effects on the apnea–hypopnea index in older adults are under‐reported. We investigated the acute effects of gabapentin (GABA) on sleep breathing in older men without sleep apnea. A double‐blind, randomized, placebo‐controlled cross‐over pilot study using a bedtime dose of gabapentin 300 mg was conducted in eight non‐obese older men. Polysomnography measured the effects of the intervention. The apnea–hypopnea index was higher in the gabapentin arm than in the placebo arm (22.4 ± 6.1 versus 12.2 ± 4.3, P ≤ 0.05, d: 0.67), as was the oxygen desaturation index (20.6 ± 5.8 versus 10.8 ± 3.9, P ≤ 0.05, d: 0.68). The number needed to harm was four. A subset analysis demonstrated that differences in sleep respiratory parameters were present only during non‐rapid eye movement sleep, as well as only in the supine position. No adverse events were reported. Hence, gabapentin worsened sleep breathing acutely compared with placebo. Long‐term clinical trials are warranted to elucidate the clinical relevance of these findings for the safety profile of GABAergic agents.     

Efficacy and safety of the SQ‐standardized grass allergy immunotherapy tablet in mono‐ and polysensitized subjects

The efficacy of single‐allergen‐specific immunotherapy in polysensitized subjects is a matter of debate. We therefore performed a post hoc analysis of pooled data from six randomized, double‐blind, placebo‐controlled trials (N = 1871) comparing the efficacy and safety of the SQ‐standardized grass allergy immunotherapy tablet (AIT), Grazax (Phleum pratense 75 000 SQ‐T/2800 BAU, ALK, Denmark), in mono‐ and polysensitized subjects. A statistically significant reduction in the mean total combined symptom/medication score (TCS) of 27% was demonstrated in actively treated subjects compared with placebo (P < 0.0001). This was not dependent on sensitization status (P = 0.5772), suggesting a similar treatment effect in mono‐ and polysensitized subjects (i.e. reductions of the TCSs of 28% and 26%, respectively, both P < 0.0001). Finally, a comparable and favourable safety profile of grass AIT was demonstrated in the two subgroups. Thus, no difference in efficacy and safety of single‐allergen grass AIT was observed between mono‐ and polysensitized subjects.     

Validity,potential clinical utility and comparison of a consumer activity tracker and a research‐grade activity tracker in insomnia disorder II: Outside the laboratory

Accurate assessment of sleep can be fundamental for monitoring, managing and evaluating treatment outcomes within diseases. A proliferation of consumer activity trackers gives easy access to objective sleep. We evaluated the performance of a commercial device (Fitbit Alta HR) relative to a research‐grade actigraph (Actiwatch Spectrum Pro) in measuring sleep before and after a cognitive behavioural intervention in insomnia disorder. Twenty‐five individuals with DSM‐5 insomnia disorder (M = 50.6 ± 15.9 years) wore Fitbit and Actiwatch and completed a sleep diary during an in‐laboratory polysomnogram, and for 1 week preceding and following seven weekly sessions of cognitive‐behavioural intervention for insomnia. Device performance was compared for sleep outcomes (total sleep time, sleep latency, sleep efficiency and wake after sleep onset). The analyses assessed (a) agreement between devices across days and pre‐ to post‐treatment, and (b) whether pre‐ to post‐treatment changes in sleep assessed by devices correlated with clinical measures of change. Devices generally did not significantly differ from each other on sleep variable estimates, either night to night, in response to sleep manipulation (pre‐ to post‐treatment) or in response to changes in environment (in the laboratory versus at home). Change in sleep measures across time from each device showed some correlation with common clinical measures of change in insomnia, but not insomnia diagnosis as a categorical variable. Overall, the Fitbit provides similar estimates of sleep outside the laboratory to a research grade actigraph. Despite the similarity between Fitbit and Actiwatch performance, the use of consumer technology is still in its infancy and caution should be taken in its interpretation.     

Efficacy of a language-concordant health coaching intervention for latinx with diabetes

ObjectiveTo describe the effect of a language-concordant health coaching intervention for Spanish-speaking patients with limited English proficiency (LEP) and uncontrolled Type 2 Diabetes (T2D) on glycemic control, anxiety, depression, and diabetes self-efficacy.Methods64 patients with T2D were randomly assigned to a control or intervention group. Outcomes were assessed by blood work and surveys pre and post intervention.ResultsThe mean sample age was 47.8 years (SD=11.3) and 81% were female. HbA1c was not significantly different between groups at baseline. The intervention group’s HbA1c was significantly lower at times 2 and 3 than in the control arm (p < .01 and p < .001). There were significant reductions in the intervention group’s mean HbA1c levels from baseline 10.37 to midpoint 9.20, p < .001; and from baseline 10.42 to study end 8.14, p < .001. Depression and anxiety scores significantly decreased (p < .05 and p < .001), and diabetes self-efficacy significantly increased (p < .001).ConclusionHealth coaching led to statistically significant and clinically meaningful decreases in HbA1c, depression, and anxiety scores among LEP Latinx adults with uncontrolled T2D.Practice ImplicationsHeath coaching can be conducted in primary care clinics by nurses or advanced practice nurses. The short-term intervention tested here could be adapted to the clinical setting.     

Link between insomnia and perinatal depressive symptoms: A meta‐analysis

Evidence shows the possible link between insomnia and perinatal depressive symptoms. In order to find a convergent quantitative answer, we collected data via the search of Medline, EMBASE and reference tracking, which included nine studies (a total sample of 1,922 women). An aggregate effect size estimate (correlation coefficient) was generated using the comprehensive meta‐analysis software. For the meta‐analytic procedure, a random effects model was set a priori. Moderating factors, including study design, method of assessment of depression, geographical origin of data, publication year, mean age, % married, breastfeeding rate, quality and type of data, % primiparous and history of depression, were examined via categorical or univariate mixed‐effects (method of moments) meta‐regression methods. Heterogeneity and publication bias were examined using standard meta‐analytic approaches. We found a significant, medium‐size relationship between insomnia and perinatal depressive symptoms (point estimate, 0.366; 95% confidence interval [CI], 0.205–0.508; p < 0.001; n = 9) and this was significantly heterogeneous (Q, 118.77; df, 8; p < 0.001; I², 93.26%). The effect size estimate was significant for studies reporting no history of depression (point estimate, 0.364; 95% CI, 0.035–0.622; p < 0.05; n = 5) and for study design. With meta‐regression, no moderating factor (age, marriage rate, breastfeeding rate, pregnancy history or publication year) significantly mediated the effect size estimate. The depression assessment scale used, but not other categorical variables, explained the magnitude of heterogeneity. We found that insomnia during the perinatal period is associated with depressive symptoms, which warrants screening pregnant mothers for insomnia and depression.     

The contribution of dispositional optimism to understanding insomnia symptomatology: Findings from a cross‐sectional population study in Austria

Attitudes and expectations of people towards their lives are essential to future health outcomes. Growing evidence has linked dispositional optimism to beneficial health outcomes, such as exceptional longevity, healthy aging and better sleep quality. We describe the association between dispositional optimism and chronic insomnia, considering potential mediators, in the Austrian Sleep Survey (N = 1,004), a population‐based cross‐sectional study conducted in 2017. Optimism was measured using the validated Life Orientation Test‐Revised, and four different definitions were used to assess chronic insomnia. Three definitions were based on the criteria of chronic insomnia according to the International Classification of Sleep Disorders (3rd edn). Age‐ and multivariable‐adjusted logistic regression models were used to calculate odds ratios (OR) and 95% confidence intervals (CIs). Among Austrians who were more optimistic, chronic insomnia risk was lower compared with those less optimistic (middle versus bottom tertile of optimism score: OR = 0.39, 95% CI, 0.22–0.70; and top versus bottom tertile: OR = 0.28, 95% CI, 0.14–0.54; p‐trend < .001). Results were similar for all four definitions of insomnia, and differed slightly between men and women. Happiness, depression and health status confounded the association, whereas lifestyle did not. Promoting dispositional optimism could represent a simple and accessible strategy to improve sleep quality and lower insomnia risk, with downstream beneficial health effects. Further research is needed to clarify the prevention potential of interventions targeting this mental trait.