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 (ß = -.151, p = .010) and self-esteem (ß = -.141, p = .009) and it also predicted subsequent PTSD symptoms (ß = .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.

Dissociative symptoms among community health service users in Hong Kong: a longitudinal study of clinical course and consequences.

Background: Previous studies have demonstrated the high prevalence of dissociative symptoms and their association with considerable healthcare costs. However, there is a lack of studies that describe whether dissociative symptoms persist and lead to other clinical outcomes over time in the community.Objectives: This study investigated the persistence, predictors, and consequences of dissociative symptoms in the community.Methods: We analyzed longitudinal data in a sample of community health service users in Hong Kong (N = 173).Results: A relatively high proportion (63.6%) of participants with baseline dissociative symptoms continued to exhibit dissociative symptoms after approximately 9 months. Baseline non-betrayal trauma predicted subsequent dissociative symptoms (ß = .141, p = .024). Participants with baseline dissociative symptoms were more likely to have received subsequent emergency mental health services (9.1% vs 0.7%, p = .005). Baseline dissociative symptoms significantly predicted subsequent post-traumatic symptoms (ß = .165 to .191, p < .05) and difficulty in social and occupational participation (ß = -.152 to -.182, p < .05) even after controlling for baseline scores, trauma exposure, and use of professional support. The predictive role of dissociative symptoms on subsequent disturbances in self-organization symptoms and social participation difficulty remained significant after applying the Bonferroni correction.Conclusions: This is one of the very few studies showing that dissociative symptoms are persistent to a certain degree and could predict other symptoms and subsequent impairments even in community settings. Factors that affect the trajectory of dissociative symptoms should be further investigated. Regular screening for dissociative symptoms is recommended. Considering its prevalence, persistence, and clinical and social consequences, dissociation should be given greater public health attention.

Dissociative symptoms have been linked to considerable healthcare costs.The persistence and consequences of dissociation in the community had not been previously reported.This study showed that dissociative symptoms persisted to a certain degree and predicted subsequent impairments after approximately 9 months.Dissociation should be given greater public health attention.

Is Cognitive Behavioral Therapy for Insomnia Effective for Improving Sleep Duration in Individuals with Insomnia? A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Accumulating evidence suggests that sleep duration is a critical determinant of physical and mental health. Half of the individuals with chronic insomnia report less than optimal sleep duration. Cognitive behavioral therapy for insomnia (CBT-I) is an effective treatment for reducing sleep difficulties in individuals with chronic insomnia. However, its effectiveness for increasing sleep duration is less well-established and a synthesis of these findings is lacking. PURPOSE: To provide a synthesis of findings from randomized controlled trials (RCTs) on the effect of CBT-I on subjective and objective total sleep time (TST). METHODS: A systematic search was performed on articles published from 2004 to 05/30/2021. A total of 43 RCTs were included in the meta-analysis. Publication biases were examined. Meta-regressions were conducted to examine if any sample or treatment characteristics moderated the effect sizes across trials. RESULTS: We found a small average effect of CBT-I on diary-assessed TST at post-treatment, equivalent to an approximately 30-min increase. Age significantly moderated the effects of CBT-I on diary-measured and polysomnography-measured TST; older ages were associated with smaller effect sizes. Contrarily, a negative, medium effect size was found for actigraphy-assessed TST, equivalent to an approximately 30-min decrease. Publication biases were found for diary data at follow-up assessments suggesting that positive findings were favored. CONCLUSIONS: CBT-I resulted in improvements in TST measured by sleep diaries and polysomnography (in adults). These improvements were not corroborated by actigraphy findings. Theoretical and clinical implications were discussed.

Chronic insomnia is a common sleep disorder and can be treated effectively with cognitive behavioral therapy for insomnia (CBT-I). Previous research has consistently shown that CBT-I can reduce sleep difficulties such as difficulty falling and maintaining sleep. The effects of CBT-I on increasing sleep duration are less consistent across studies. This meta-analysis reviewed 43 randomized controlled trials of CBT-I published between 01/01/2004 and 05/30/2021 and synthesized the findings of the effects of CBT-I on sleep duration, measured subjectively and objectively. We found that CBT-I increased sleep duration measured by sleep diaries and polysomnography by about 30 min at post-treatment. This effect is weaker in people with older ages. Contrarily, CBT-I is found to lead to a decrease in sleep duration for about 30 min when sleep duration is measured by actigraphy. The discrepant findings between different sleep measurements reinforce the notion that different measures of sleep assess different aspects of sleep, and that different sleep measurements may have different responsiveness to the treatment of insomnia. Additionally, most people do not achieve the recommended sleep duration at the end of CBT-I. Future studies are needed to evaluate interventions that can help individuals with insomnia increase and maintain optimal sleep duration.

Daily Associations of Sleep Quality and Sleep Duration with Anxiety in Young Adults: The Moderating Effect of Alexithymia.

OBJECTIVES: The present study examined the daily, within-individual associations of anxiety with sleep quality and sleep duration and the moderating effects of alexithymia on these associations in community-dwelling young adults. It was hypothesized that daily anxiety and sleep parameters would be bidirectionally related and alexithymia would moderate these relationships. METHOD: Participants completed morning and evening diaries assessing daily anxiety and sleep parameters for 30 consecutive days. They also completed questionnaires assessing baseline sleep parameters, anxiety, and alexithymia. Multilevel modeling was used to evaluate the within-individual associations between daily anxiety and sleep parameters and whether between-individual differences in alexithymia moderated these associations. RESULTS: Higher anxiety relative to personal averages across the study period was associated with shorter sleep duration at night. Poorer sleep quality and shorter sleep duration relative to personal averages were associated with higher next-day anxiety. A significantly stronger association between poorer sleep quality and higher next-day anxiety was observed in individuals with higher levels of alexithymia. CONCLUSION: Daily anxiety and sleep quantity are bidirectionally associated within individuals in community-dwelling young adults. Poorer sleep quality was associated with higher next-day anxiety but not vice versa. Individuals with higher levels of alexithymia might be more vulnerable to the effects of poor sleep on next-day anxiety.