Frequent nightmares and its associations with psychological and sleep disturbances in hospitalized patients with cardiovascular diseases

Nightmares share genetic risk factors with sleep and psychiatric traits

Nightmares are vivid, extended, and emotionally negative or negative dreams that awaken the dreamer. While sporadic nightmares and bad dreams are common and generally harmless, frequent nightmares often reflect underlying pathologies of emotional regulation. Indeed, insomnia, depression, anxiety, or alcohol use have been associated with nightmares in epidemiological and clinical studies. However, the connection between nightmares and their comorbidities are poorly understood. Our goal was to examine the genetic risk factors for nightmares and estimate correlation or causality between nightmares and comorbidities. We performed a genome-wide association study (GWAS) in 45,255 individuals using a questionnaire-based assessment on the frequency of nightmares during the past month and genome-wide genotyping data. While the GWAS did not reveal individual risk variants, heritability was estimated at 5%. In addition, the genetic correlation analysis showed a robust correlation (rg > 0.4) of nightmares with anxiety (rg = 0.671, p = 7.507e-06), depressive (rg = 0.562, p = 1.282e-07) and posttraumatic stress disorders (rg = 0.4083, p = 0.0152), and personality trait neuroticism (rg = 0.667, p = 4.516e-07). Furthermore, Mendelian randomization suggested causality from insomnia to nightmares (beta = 0.027, p = 0.0002). Our findings suggest that nightmares share genetic background with psychiatric traits and that insomnia may increase an individual's liability to experience frequent nightmares. Given the significant correlations with psychiatric and psychological traits, it is essential to grow awareness of how nightmares affect health and disease and systematically collect information about nightmares, especially from clinical samples and larger cohorts.

Association of healthy sleep pattern with risk of recurrent cardiovascular events among patients with coronary heart disease

AIMS

To examine the association of a healthy sleep pattern with the risk of recurrent cardiovascular events among patients with coronary heart disease (CHD).

METHODS AND RESULTS

This prospective cohort study included 21 193 individuals with CHD from the UK Biobank. A healthy sleep score was generated based on a combination of chronotype, sleep duration, insomnia, and excessive daytime sleepiness. Cox proportional hazards regression models were applied to estimate the associations between healthy sleep score and recurrent cardiovascular events. During a median of 11.1 years of follow up, we documented 3771 recurrent cardiovascular events, including 1634 heart failure cases and 704 stroke cases. After multivariable adjustment, including lifestyle factors, medical history, and CHD duration, sleep 7-8 h/day, never/rarely insomnia, and no frequent daytime sleepiness were each significantly associated with a 12-22% lower risk of heart failure. In addition, compared with participants who had a healthy sleep score of 0-1, the multivariable-adjusted HR (95% CI) for participants with a healthy sleep score of 4 was 0.86 (0.75, 0.99) for recurrent cardiovascular events, 0.71 (0.57, 0.89) for heart failure, and 0.72 (0.51, 1.03) for stroke.

CONCLUSIONS

Adherence to a healthy sleep pattern was significantly associated with a lower risk of recurrent cardiovascular events among patients with CHD, especially for heart failure. These findings indicate that healthy sleep behaviours could be beneficial in the prevention of cardiovascular event recurrence.

Non-cardiac Chest Pain in Japan: Prevalence, Impact, and Consultation Behavior - A Population-based Study

Background/Aims

Non-cardiac chest pain (NCCP) is defined as recurring angina-like retrosternal chest pain of non-cardiac origin. Information about the epidemiology of NCCP in Japan is lacking. We aim to determine the prevalence and characteristics of NCCP in the Japanese general population.

Methods

Two internet-based surveys were conducted among the general population in March 2017. Questions investigated the characteristics of symptoms associated with chest pain and consultation behavior. Quality of life, anxiety, depression, and gastroesophageal reflux disease were analyzed.

Results

Five percent of the survey respondents reported chest pain. Subjects with chest pain showed higher frequencies of anxiety and depression and lower quality of life. Among subjects with chest pain, approximately 30% had sought medical attention for their symptoms. Among all consulters, 70% were diagnosed with NCCP. Females were less likely to seek consultations for chest pain than males. Further, severity and frequency of chest pain, lower physical health component summary score, and more frequent gastroesophageal reflux disease were associated with consultation behavior. Subjects with NCCP and cardiac chest pain experienced similar impacts on quality of life, anxiety, and depression. Among subjects with NCCP, 82% visited a primary-care physician and 15% were diagnosed with reflux esophagitis.

Conclusions

The prevalence of chest pain in this sample of a Japanese general population was 5%. Among all subjects with chest pain, less than one-third consulted physicians, approximately 70% of whom were diagnosed with NCCP. Sex and both the severity and frequency of chest pain were associated with consultation behavior.

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).