The Nightmare Disorder Index: development and initial validation in a sample of nurses

Nightmare Disorder

This article presents a comprehensive review of nightmare disorder, covering diagnosis, treatment approaches, guidelines, and considerations. It begins with an introduction, defining the disorder and addressing its prevalence and psychosocial implications. The article explores assessment tools for diagnosis and then delves into psychological and pharmacologic treatment modalities, examining their efficacy and side effects. Considerations for optimizing therapeutic outcomes are highlighted, including medication versus psychotherapy, co-morbidities, cultural implications, and the use of technology and service animals. The review concludes by offering key recommendations for effective treatment and clinical care for individuals with nightmare disorder.

Factor Analysis and Validation of the Disturbing Dream and Nightmare Severity Index in an Inpatient Sample

STUDY OBJECTIVES

The Disturbing Dream and Nightmare Severity Index (DDNSI) has been used widely in research and clinical practice without psychometric evidence supporting its use in clinical samples. The present study aimed to explore and confirm the factor structure of the DDNSI in an inpatient sample. We also sought to test the measure's construct validity.

METHODS

Two samples of U.S. inpatients including adult (N = 937) and adolescent (N = 274) participants provided data on nightmares (i.e. DDNSI), sleep quality (i.e. the Pittsburgh Sleep Quality Index) and related psychopathology symptoms (e.g. depression, posttraumatic stress disorder, anxiety).

RESULTS

Exploratory and confirmatory factor analyses found the six original items of the DDNSI to load onto a single latent factor.

CONCLUSIONS

The DDNSI was found to be a valid measure of nightmare frequency and distress, as it was significantly correlated with the items related to disturbing dreams, and the DDNSI was able to differentiate between nightmares and psychopathology symptoms. Though this research comes nearly two decades after the initial creation and use of the DDNSI, it provides a foundation for the scientific rigor of previous and future studies on nightmares using the DDNSI.

A prospective study of nightmare disorder among Chinese adults in Hong Kong: Persistence and mental health outcomes

OBJECTIVES

Previous studies showed that nightmares are prevalent and are associated with negative health outcomes. However, no empirical data is available demonstrating the extent to which nightmare disorder persists over time. Current literature provides a limited understanding of the trajectory and wider mental health outcomes of nightmare disorder. This longitudinal study examined the persistence and mental health outcomes of nightmare disorder.

METHODS

A total of 230 Hong Kong Chinese adults completed standardized assessments twice with an interval of about 6 months.

RESULTS

Over half (66.7%) of the participants with probable nightmare disorder at baseline remained to meet the DSM-5 criteria for the disorder at follow-up. Participants with probable nightmare disorder at baseline were significantly more likely to screen positive for PTSD (82.1% vs 18.3%) (p < .001) (p < .001), and they reported higher rates of mental health service usage at both timepoints (p = .001 to .003). Baseline nightmare disorder severity was negatively associated with subsequent self-rated mental health (β = -.151, p = .010) and self-esteem (β = -.141, p = .009) and it also predicted subsequent PTSD symptoms (β = .122, p = .012).

CONCLUSIONS

This study provides first empirical data showing that nightmare disorder could be persistent over time. Nightmare disorder symptoms are associated not only with PTSD symptoms but also with a broader range of mental health issues. This study points to the public health importance of identifying and managing nightmare disorder symptoms in the community. Additionally, the presence of nightmare disorder symptoms may be a helpful indicator for identifying post-traumatic stress.

Sleep Disturbances and Hygiene of Adolescent Female Survivors of Domestic Minor Sex Trafficking

INTRODUCTION

This cross-sectional quantitative study investigated the sleep hygiene and disturbances of adolescent female survivors of domestic minor sex trafficking (DMST) compared to an online sample of community-dwelling adolescent females.

METHOD

Community-dwelling adolescent females (aged 13-17 years, n = 61) and survivors of DMST housed in residental care (aged 12-17 years, n = 19) completed the Children's Report of Sleep Patterns (adolescent version). Descriptive statistics on sleep health in both samples were computed and compared using chi-square and t-tests.

RESULTS

Among the survivors of DMST, the majority reported insufficient sleep duration, okay-to-poor sleep quality, waking thirsty, and frequent nightmares. Compared with community-dwelling adolescents, survivors of DMST had more symptoms of insomnia, sleepiness, nightmares, and waking thirsty (p < .05).

DISCUSSION

Sleep disturbances among adolescent female survivors of DMST may be more prevalent than in community-dwelling adolescent females. Further empirical research on appropriate assessment and trauma-informed treatment of sleep in this population is needed.

Sex differences in US military personnel with insomnia, obstructive sleep apnea, or comorbid insomnia and obstructive sleep apnea

STUDY OBJECTIVES

The aim of this study was to evaluate sex-related differences in symptoms of sleep disorders, sleep-related impairment, psychiatric symptoms, traumatic brain injury, and polysomnographic variables in treatment-seeking military personnel diagnosed with insomnia, obstructive sleep apnea (OSA), or comorbid insomnia and OSA (COMISA).

METHODS

Participants were 372 military personnel (46.2% women, 53.8% men) with an average age of 37.7 (standard deviation = 7.46) years and median body mass index of 28.4 (5.50) kg/m2. Based on clinical evaluation and video-polysomnography, participants were diagnosed with insomnia (n = 118), OSA (n = 118), or COMISA (n = 136). Insomnia severity, excessive daytime sleepiness, sleep quality, nightmare disorder, sleep impairment, fatigue, posttraumatic stress disorder, anxiety, depression symptoms, and traumatic brain injury were evaluated with validated self-report questionnaires. Descriptive statistics, parametric and nonparametric t-tests, and effect sizes were used to assess sex differences between men and women.

RESULTS

There were no significant differences between women and men with insomnia or OSA in sleep-related symptoms, impairment, or polysomnography-based apnea-hypopnea index. Military men with COMISA had a significantly greater apnea-hypopnea index as compared to military women with COMISA, but women had greater symptoms of nightmare disorder, posttraumatic stress disorder, and anxiety.

CONCLUSIONS

In contrast to civilian studies, minimal differences were observed in self-reported sleep symptoms, impairment, and polysomnography metrics between men and women diagnosed with the most frequent sleep disorders in military personnel (ie, insomnia, OSA, or COMISA) except in those with COMISA. Military service may result in distinct sleep disorder phenotypes that differ negligibly by sex.

CITATION

Mysliwiec V, Pruiksma KE, Matsangas P, et al. Sex differences in US military personnel with insomnia, obstructive sleep apnea, or comorbid insomnia and obstructive sleep apnea. J Clin Sleep Med. 2024;20(1):17-30.

Relationship between nightmare distress and depressive symptoms in Chinese emergency department nurses: A cross-sectional study

BACKGROUND

Most of the recent research on nightmare distress and depressive symptoms has focused on adolescents and students, with less research on the nurse population. Emergency department nurses are at high risk for nightmare distress and depressive symptoms, but no studies have been conducted to explore the relationship between the two; thus, further investigation is needed.

AIM

To understand the relationship between nightmare distress and depressive symptoms among emergency department nurses in China.

METHODS

A convenience sampling method was used to select 280 emergency department nurses from nine provinces, including Jiangxi, Sichuan, Jiangsu, and Shanxi Provinces. The Chinese version of the Nightmare Distress Questionnaire and the Center for Epidemiological Studies Depression Scale (CES-D) were administered.

RESULTS

Emergency department nurses' nightmare distress scores were positively associated with depressive symptom scores (r = 0.732), depressed affect (r = 0.727), somatic symptoms (r = 0.737), and interpersonal difficulty (r = 0.647). Further multiple linear regression analyses showed that education level, work pressure, self-reported health, and CES-D scores were factors that influenced nightmare distress among Chinese emergency department nurses (P < 0.05).

CONCLUSION

Nightmare distress is closely associated with depressive symptoms in Chinese emergency department nurses, and early intervention is recommended for professionals with this type of sleep disorder to reduce the occurrence of depressive symptoms.

Nightmare distress, insomnia and resilience of nursing staff in the post-pandemic era

Introduction

The pandemic has led to notable psychological challenges among healthcare professionals, including nurses.

Objective

Our aims of this study were to assess insomnia and nightmare distress levels in nurses and investigate their association with mental resilience.

Methods

Nurses participated in an online survey, which included the Nightmare Distress Questionnaire (NDQ), Brief Resilience Scale (BRS) and Athens Insomnia Scale (AIS). Demographic information, such as age, professional experience and gender, was also collected.

Results

The study included 355 female and 78 male nurses. Findings revealed that 61.4% had abnormal AIS scores, 7% had abnormal NDQ scores and 25.4% had low BRS scores. Female nurses had higher AIS and NDQ scores but lower BRS scores compared to males. BRS demonstrated negative correlations with both AIS and NDQ. Multiple regression analysis indicated that NDQ accounted for 24% of the AIS variance, with an additional 6.5% explained by the BRS. BRS acted as a mediator, attenuating the impact of nightmares on insomnia, with gender moderating this relationship.

Conclusions

Nursing staff experienced heightened sleep disturbances during the pandemic, with nightmares and insomnia being prevalent. Nightmares significantly contributed to insomnia, but mental resilience played a vital role in mitigating this effect. Strategies are warranted to address the pandemic's psychological impact on nursing professionals.

Reliability and validity of the Chinese version of the Nightmare disorder index in adolescents

The Nightmare Disorder Index Questionnaire (NDI) was developed to measure the impact of nightmares. The purpose of this study was to investigate the psychometric properties of NDI among Chinese adolescents. This study investigated the validity and internal consistency of the Nightmare Disorder Index Chinese (NDI-CV) among 6014 Chinese adolescents who completed the NDI-CV, Nightmare Distress Questionnaire-Chinese Version (NDQ-CV), Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Chinese Adolescent Daytime Sleepiness Scale (CADSS), Generalized Anxiety Disorder-7 Questionnaire (GAD-7), and Patient Health Questionnaire-9 (PHQ-9). In addition, we investigated the test-retest reliability of the NDI-CV among 423 adolescents who completed a retest of the NDI-CV after a 2-week interval. Finally, NDI-CV demonstrated good psychometric properties in a sample of Chinese adolescents (Cronbach's α coefficient of 0.876), and the 95% confidence interval for the 2-week retest correlation coefficient was 0.675-0.977 (p < 0.001).

Nightmares: an independent risk factor for cardiovascular disease?

STUDY OBJECTIVES

Prior work has established associations between post-traumatic stress disorder (PTSD), disrupted sleep, and cardiovascular disease (CVD), but few studies have examined health correlates of nightmares beyond risks conferred by PTSD. This study examined associations between nightmares and CVD in military veterans.

METHODS

Participants were veterans (N = 3468; 77% male) serving since September 11, 2001, aged 38 years (SD = 10.4); approximately 30% were diagnosed with PTSD. Nightmare frequency and severity were assessed using the Davidson Trauma Scale (DTS). Self-reported medical issues were assessed using the National Vietnam Veterans Readjustment Study Self-report Medical Questionnaire. Mental health disorders were established using the Structured Clinical Interview for DSM-IV. The sample was stratified by the presence or absence of PTSD. Within-group associations between nightmare frequency and severity and self-reported CVD conditions, adjusting for age, sex, race, current smoking, depression, and sleep duration.

RESULTS

Frequent and severe nightmares during the past week were endorsed by 32% and 35% of participants, respectively. Those endorsing nightmares that were frequent, severe, and the combination thereof were more likely to also evidence high blood pressure (ORs 1.42, OR 1.56, and OR 1.47, respectively) and heart problems (OR 1.43, OR 1.48, and OR 1.59, respectively) after adjusting for PTSD diagnosis and other covariates.

CONCLUSIONS

Nightmare frequency and severity among veterans are associated with cardiovascular conditions, even after controlling for PTSD diagnosis. Study findings suggest that nightmares may be an independent risk factor for CVD. Additional research is needed to validate these findings using confirmed diagnoses and explore potential mechanisms.

A comprehensive evaluation of insomnia, obstructive sleep apnea and comorbid insomnia and obstructive sleep apnea in US military personnel

STUDY OBJECTIVES

The aim of this study was to characterize the sleep disorders of insomnia, obstructive sleep apnea (OSA), and comorbid insomnia and OSA (COMISA) in active duty military personnel.

METHODS

Prospective observational study of 309 military personnel with a mean age of 37.17 years (SD = 7.27). Participants served in four branches of the U.S. military (47.9% Air Force, 38.8% Army, 11.3% Navy, and 1.9% Marines). Sleep diagnoses were rendered after video-polysomnography and a clinical evaluation. Validated self-report measures assessed insomnia severity, excessive daytime sleepiness, sleep quality, disruptive nocturnal behaviors, nightmare disorder, shift work disorder (SWD), sleep impairment, fatigue, posttraumatic stress disorder (PTSD) symptoms, anxiety, depression, and traumatic brain injury (TBI). General linear models and Pearson chi-square tests were used for between-group differences in data analyses.

RESULTS

Insomnia was diagnosed in 32.7%, OSA in 30.4% and COMISA in 36.9%. Compared to military personnel with OSA alone, those with insomnia only and COMISA had significantly greater insomnia severity, disruptive nocturnal behaviors, sleep-related impairment, rates of nightmare disorder, and poorer sleep quality (all Ps < .05). They also reported greater symptoms of fatigue, PTSD, anxiety, and depression (all Ps < .05). There were no significant differences among the three sleep disorder diagnostic groups on sleepiness, SWD, or TBI.

CONCLUSIONS

Military personnel with insomnia only and COMISA overall report worsened symptoms of sleep disorders, sleep-related impairment, fatigue, and psychiatric disorders than those with OSA. Results highlight the importance of a comprehensive assessment for sleep-related impairment, sleep, and comorbid disorders in military personnel with clinically significant sleep disturbances.

Symptom dynamics among nightmare sufferers: An intensive longitudinal study

Nightmares are considerably prevalent in the general population and are known to be closely associated with a variety of mental disorders. However, not much is known about the immediate antecedents and consequences of nightmares. Therefore, we used intensive longitudinal assessments to investigate the night-to-night within-person associations between nightmares on the one hand and fear of sleep, somatic as well as cognitive pre-sleep arousal, and sleep quality on the other hand. Young women with regular nightmares (n = 16) maintained a sleep diary for around 30 days; upon awaking, the participants reported on nightmares and sleep quality during the past night as well as the pre-sleep levels of arousal and fear of sleep (which resulted in 461 observations). Participants also wore an actigraph, which provided objective sleep parameters. Multilevel modeling showed that higher levels of fear of sleep and lower subjective sleep quality were significantly associated with higher levels of nightmare distress. Furthermore, we found individual differences in the strength of these associations, which implies that factors proximate to nightmares may vary across individuals. Pre-sleep arousal, however, did not show expected within-person associations with nightmares or fear of sleep. These findings highlight the crucial role of fear of sleep in the etiology of nightmares and sleep disturbances, while pointing to the importance of pursuing individual, personalised models that explain heterogeneity in the process of triggering nightmares.

The Nightmare Quality of Life Questionnaire

RATIONALE

Patient-centered outcomes are increasingly sought to evaluate social interactions and healthcare interventions in patients with sleep disorders. Yet, measures to assess quality of life (QoL) are lacking for those who experience nightmares.

OBJECTIVE

The aim of the study is to describe the development and validation of a new health-related quality of life (HRQoL) instrument for patients with nightmares.

METHODS

Attributes obtained from a focus group of patients (n = 113) with established nightmares were analyzed using exploratory factor analysis to elicit salient QoL themes for the new instrument. A validation cohort (n = 34) was used to determine the psychometric performance of the 16-item questionnaire including item-scaling, concurrent validity, and test-retest reliability tested four weeks apart.

RESULTS

Four factors (sleep health, emotional and psychological well-being, social interaction, and motivation) explained 53.9% of the total variance. The Nightmare Quality of Life (NQoL) showed good internal consistency (Cronbach's alpha 0.85) and test-retest reliability (ICC = 0.89). Concurrent validity was evidenced by a strong correlation with the Nightmare Distress Questionnaire (r = 0.87; p < .001) and more modest associations with the Nightmare Frequency Questionnaire (r = , 0.69; p < .001), SF-36 (r = -0.68; p < .001), and PSQI (r = 0.45; p = .007).

CONCLUSIONS

The NQoL has demonstrable construct validity and reliability and represents a promising multi-dimensional instrument to assess outcome measures for quality of life in patients with nightmares.

Shift Work Disorder Index: initial validation and psychosocial associations in a sample of nurses

STUDY OBJECTIVES

Shift work is common yet does not always result in Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5)-defined shift work sleep disorder (SWD). This study reports on the reliability and validity of the DSM-5 informed Shift Work Disorder Index (SWDI), the presence of probable SWD in nurses, and demographic, sleep, and psychosocial correlates.

METHODS

Nurses (n = 454) completed the SWDI, psychosocial, and demographic questionnaires. Of the sample, n = 400 completed 14 days of sleep diaries, actigraphy, and additional questionnaires.

RESULTS

The global SWDI demonstrated excellent internal consistency (α = .94), as well as good convergent and divergent validity in the nurse sample. Thirty-one percent of nurses were past-month shift workers, with 14% (ie, 44% of shift workers) having probable SWD based on SWDI. Nurses who worked shift work and/or met SWD criteria were more likely to be younger and unmarried and less likely to have children than day workers and reported greater evening chronotype, insomnia, nightmares, and sleep-related impairment, greater depression, anxiety, posttraumatic stress, and perceived stress symptoms, as well as later and more variable sleep midpoint (actigraphy), shorter sleep duration (actigraphy, diaries), and lower sleep efficiency (diaries).

CONCLUSIONS

The SWDI is an efficient and valid self-report assessment of DSM-5-defined SWD. Shift work and/or SWD were prevalent and associated with worse sleep and psychosocial health, particularly among nurses with probable SWD.

CITATION

Taylor DJ, Dietch JR, Wardle-Pinkston S, et al. Shift Work Disorder Index: initial validation and psychosocial associations in a sample of nurses. J Clin Sleep Med. 2022;18(10):2339-2351.

Nightmare disorder and low back pain in veterans: cross-sectional association and effect over time

Low back pain (LBP) disproportionately impacts US military veterans compared with nonveterans. Although the effect of psychological conditions on LBP is regularly studied, there is little published to date investigating nightmare disorder (NMD) and LBP. The purpose of this study was to (1) investigate whether an association exists between NMD and LBP and (2) estimate the effect of NMD diagnosis on time to LBP. We used a retrospective cohort design with oversampling of those with NMD from the Veterans Health Administration (n = 15 983). We used logistic regression to assess for a cross-sectional association between NMD and LBP and survival analysis to estimate the effect of NMD on time to LBP, up to 60-month follow-up, conditioning on age, sex, race, index year, Charlson Comorbidity Index, depression, anxiety, insomnia, combat exposure, and prisoner of war history to address confounding. Odds ratios (with 95% confidence intervals [CIs]) indicated a cross-sectional association of 1.35 (1.13 to 1.60) and 1.21 (1.02 to 1.42) for NMD and LBP within 6 months and 12 months pre- or post-NMD diagnosis, respectively. Hazard ratios (HRs) indicated the effect of NMD on time to LBP that was time-dependent-HR (with 95% CIs) 1.27 (1.02 to 1.59), 1.23 (1.03 to 1.48), 1.19 (1.01 to 1.40), and 1.10 (0.94 to 1.29) in the first 3, 6, 9, and 12 months post-diagnosis, respectively-approximating the null (1.00) at >12 months. The estimated effect of NMD on LBP suggests that improved screening for NMD among veterans may help clinicians and researchers predict (or intervene to reduce) risk of future back pain.

Nightmare Distress as a Risk Factor for Suicide Among Adolescents with Major Depressive Disorder

PURPOSE

Nightmare is common and is also independently implicated in suicide risk among the adolescent population. Adolescents with major depressive disorder (MDD) are at an increased risk of suicide. Therefore, comorbid nightmares may amplify suicide risk among this clinical population. This study aimed to explore the effects of nightmares on suicide risk among adolescents with MDD.

PATIENTS AND METHODS

Subjects were 499 outpatients aged 12-18 in four large psychiatric hospitals clinic of China, from January 1 to October 31, 2021. Simultaneously, we matched 499 healthy controls according to gender and age. All participants underwent affective state (depressive and anxiety symptoms) and sleep variable (nightmare frequency/distress, insomnia symptoms, and daytime sleepiness) evaluation as well as MDD diagnoses and determination of suicide risk by a fully structured diagnostic clinical interview.

RESULTS

Adolescents with MDD reported a higher incidence of frequent nightmares (at least one night per week) and level of nightmare distress than healthy controls (22.0% vs 6.1%; 28.85 ± 11.92 vs 17.30 ± 5.61). Over half of the patients with suicide risk (51.6%) experienced frequent nightmares compared with approximately one-third of those at a risk for suicide (30.7%). Patients with suicide risk scored scientifically higher on sleep variables, depressive and anxiety symptoms than those without the risk. Further logistic regression analysis indicated that female gender, junior grade, recurrent depressive episode, severe nightmare distress and severe depressive symptoms were independently and significantly associated with suicide risk.

CONCLUSION

Our study provided evidence that adolescents with MDD experienced a higher prevalence of frequent nightmares and suffered more nightmare distress. Nightmare distress is an independent risk factor for suicide risk.

Sleep and substance use disorder treatment: A preliminary study of subjective and objective assessment of sleep during an intensive outpatient program

BACKGROUND AND OBJECTIVES

Characteristics of sleep concerns and their relationship to mental health in heterogeneous substance use disorder (SUD) treatment settings are not well understood. The purpose of this preliminary study was to assess sleep using subjective and objective measures at two time points during SUD treatment and compare sleep changes to changes in mental health measures.

METHODS

Treatment-seeking participants completed an assessment battery at the beginning of treatment (Time 1, N = 30) and again upon treatment completion (Time 2, approximately 4 weeks later, N = 22). The majority of participants were White (80%), male (63%), and presenting for alcohol use disorder (60.0%), though almost half reported polysubstance abuse (43%). Comorbidity was common (53%). Sleep and mental health questionnaires with 1 week of actigraphy and sleep diaries were completed at both time points.

RESULTS

Most participants met the criteria for a sleep disorder and mean scores on questionnaires showed poor sleep quality, insomnia symptoms, and frequent nightmares, with sleep quality and insomnia improving over time but remaining clinically significant. Nightmares did not improve. Actigraphy indicated poor sleep at both time points. Improvement in insomnia was related to improvement in measures of mental health while changes in actigraphy variables were not related to these measures.

DISCUSSION AND CONCLUSIONS

Multiple types of sleep disturbance are prevalent in this population, with nightmares persisting throughout treatment and insomnia symptoms showing a relationship with mental health symptoms.

SCIENTIFIC SIGNIFICANCE

This was the first study to longitudinally assess mental health with subjective and objective measures of sleep across multiple types of SUDs in a community SUD treatment setting.

Disturbed Sleep in PTSD: Thinking Beyond Nightmares

Sleep disturbances frequently co-occur with posttraumatic stress disorder (PTSD). Insomnia and nightmares are viewed as core symptoms of PTSD. Yet, relations between disturbed sleep and PTSD are far more complex: PTSD is linked to a broad range of sleep disorders and disturbed sleep markedly affects PTSD-outcome. This article provides a concise overview of the literature on prevalent comorbid sleep disorders, their reciprocal relation with PTSD and possible underlying neurophysiological mechanisms. Furthermore, diagnostic procedures, standard interventions-particularly first choice non-pharmacological therapies-and practical problems that often arise in the assessment and treatment of sleep disturbances in PTSD are described. Finally, we will present some perspectives on future multidisciplinary clinical and experimental research to develop new, more effective sleep therapies to improve both sleep and PTSD.