Reliability and validity of the Japanese version of the Biological Rhythms Interview of assessment in neuropsychiatry-self report for delayed sleep-wake phase disorder

ObjectiveThe Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) might be applicable for assessing delayed sleep-wake phase disorder (DSWPD). We aimed to investigate the reliability and validity of the Japanese version of the BRIAN self-report (J-BRIAN-SR) in DSWPD patients and determine a cutoff score to identify the presence of the disorder.MethodsWe enrolled 60 newly diagnosed DSWPD outpatients and 64 age-matched healthy controls. We used Cronbach's alpha for internal reliability to evaluate J-BRIAN-SR. We confirmed the reliability of the A test and re-test using Pearson's correlation coefficient in the controls. We used confirmatory factor analysis to evaluate the factor structure of J-BRIAN-SR and referenced the Morningness-Eveningness Questionnaire (MEQ) to check concurrent validity. We analyzed the receiver operating characteristic curve (ROC) to determine the J-BRIAN-SR cutoff point for the presence of DSWPD.ResultsThe 18-component scores of the J-BRIAN-SR had an overall reliability coefficient (Cronbach's alpha) of 0.82. We confirmed a high test-retest reliability using an intraclass correlation coefficient (r = 0.84). The correlation between J-BRIAN-SR and MEQ was 0.38 (p = 0.003). The J-BRIAN-SR that we extracted by exploratory factor analysis consisted of three factors. A score of 40 points provided a sensitivity of 80.0% and a specificity of 75.6% for the positivity of DSWPD.ConclusionsThe results of the present study revealed that J-BRIAN-SR is a valid and reliable instrument for screening and evaluating the severity of DSWPD. Our findings will be useful to physicians and patients in Japan and those in clinical settings.     

Effect of exercises according to the circadian rhythm in type 2 diabetes: Parallel-group,single-blind,crossover study

Background and aimTo evaluate the effectiveness of structured exercise appropriate the circadian rhythm in terms of blood sample test (BST), functionality and quality of life (QoL) in individuals with type 2 diabetes.Methods and resultsThis was a parallel-group, single-blind, crossover study. Thirty individuals with type 2 diabetes aged 35–65 years were enrolled in the study and allocated into 2 groups as the Morning Chronotype (MC) Group (n = 15) and the Evening Chronotype (EC) Group (n = 15) using Morningness-Eveningness Questionnaire which was used to determine the chronotypes. Participants were evaluated in terms of BST, functionality and QoL at the beginning of the study (T0), at 6 (T1), 12 (T2), and 18 (T3) weeks after the study started. A structured exercise program for 3 days a week over 6 weeks was applied in accordance with the chronotypes (T1-T2) and cross-controlled for the chronotypes (T2-T3). Significant differences were found in favor of the exercise given at the appropriate time for the chronotype in all parameters in both groups within groups (T0-T1-T2-T3) (p < 0.05). In the time1group interactions, exercise in accordance with the appropriate chronotype in both groups provided the highest statistical improvement in all parameters (p < 0.05).ConclusionIt was concluded that structured exercise performed at the appropriate time for chronotype improves HbA_1c, fasting blood glucose, HDL-LDL cholesterol, triglyceride, total cholesterol, functionality and quality of life in type 2 diabetes. This variation in blood values was observed to reflect the quantitative effects of exercise administered according to the circadian rhythm in individuals with type 2 diabetes.Trial registrationClinicalTrials.gov (NCT04427488). The protocol of the study was registered at ClinicalTrials.gov (NCT04427488).     

Eveningness and poor sleep quality independently contribute to self-reported depression severity in psychiatric inpatients with affective disorder

Background Chronotype and insomnia have been related to the development and to an unfavourable course of depression. However, the mutual relationship of both risk factors is as yet unclear, especially in acute, clinically manifest depressive disorders. Aims The present study was carried out to elucidate the separate direct and indirect influence of chronotype and poor sleep quality on depression severity in patients hospitalized for depression. Methods Depression severity (BDI-II), chronotype (Morningness–Eveningness Questionnaire), and subjective sleep quality (Pittsburgh Sleep Quality Index total score) were assessed concurrently in inpatients with a depressive syndrome and insomnia during routine treatment. Correlations, multiple regression and bootstrapping methods for testing mediation models were applied to assess the independent direct and indirect effects of chronotype and sleep quality on depression severity, after adjusting for effects of age and gender. Results Data from 57 consecutively admitted patients (88% with major depression) were analyzed (68% women, mean age 41?±?13 years). Significant correlations between morningness–eveningness (p?<0.05) or sleep quality (p?<0.01) and depression severity were found; in a multiple regression model comprising chronotype, sleep quality, age and gender, only chronotype (p?<0.05) and sleep disturbances (p?<0.01) remained as independent significant concurrent predictors of depression severity (R²?=?0.184, p?<0.01). Two mediation models revealed no significant results. Conclusions Eveningness and poor subjective sleep quality were independently and directly associated with higher depression severity in inpatients with depressive syndromes. Chronotype and sleep quality should be taken into account not only in risk assessment and prevention but also in hospitalized patients to develop and improve treatment options.     

Chronotype ontogeny related to gender

Chronotype is an established concept designed to identify distinct phase relationships between the expression of circadian rhythms and external synchronizers in humans. Although it has been widely accepted that chronotype is subjected to ontogenetic modulation, there is no consensus on the interaction between age and gender. This study aimed to determine the relationship between age- and gender-related changes in the morningness-eveningness character in a large sample of people. A total of 14,650 volunteers were asked to complete the Brazilian version of the Horne and Östberg chronotype questionnaire. The data demonstrated that, on average, women were more morning-oriented than men until the age of 30 and there were no significant differences between men and women from 30 to 45 years of age. In contrast to the situation observed until the age of 30, women older than 45 years were more evening-oriented than men. These results suggest that the ontogenetic development of the circadian timekeeping system is more plastic in men, as represented by the larger amplitude of chronotype changes throughout their aging process. The phase delay of adolescence and phase advance of the elderly seem to be phenomena that are more markedly present in men than in women. Thus, our data, for the first time, provide support that sharply opposes the view that there is a single path toward morningness as a function of age, regardless of gender.     

Evaluation of the relationship between chronotype and biochemical findings,nutrition and gastrointestinal symptoms in inflammatory bowel patients

This study was conducted with 39 inpatients diagnosed with IBD in the gastroenterology department of Samsun Ondokuz Mayis University Health Application and Research Center to evaluate the relationship between chronotype and biochemical findings, nutrition, and gastrointestinal symptoms in patients with inflammatory bowel disease. The data were collected using a general information form, Food Frequency Questionnaire, Gastrointestinal Symptom Rating Scale, and Morning-Evening Questionnaire. The biochemical findings of the patients were obtained from the medical records. Statistical analysis of the patients included in the study was performed with the SPSS package program. For all analyses, p < 0.05 was considered statistically significant. Twenty-eight patients were diagnosed with ulcerative colitis and 11 with Crohn's disease. There was a significant relationship between chronotype and daily polyunsaturated fatty acid and vitamin B₆ intake in female subjects (p < 0.05). There was also a significant relationship between chronotype and percentage of carbohydrate consumed, polyunsaturated and saturated fatty acid intake in male subjects (p < 0.05). A significant relationship was found between chronotype and serum glucose, hematocrit, magnesium, and iron levels (p < 0.05). It was determined that while E-type had higher glucose and magnesium levels; M-type had higher hematocrit and iron levels. It was observed that there was a relationship between chronotype and biochemical findings and nutrition in patients with IBD. Chronotype is easy to determine and these results show that it should be considered as a factor when evaluating nutrition and clinical status in patients with IBD.     

Sleep timing,chronotype, mood,and behavior at an Arctic latitude (69°N)

ObjectiveDaylight is an important zeitgeber for entraining the circadian rhythm to a 24 h clock cycle, especially within the Polar circle, which has long Polar nights several months each year. Phase delays in sleep timing may occur, but the mean shift is normally small. However, the individual variation in phase shifts is large, implicating moderating factors. Here we examined the role of several self-regulatory variables (mood and fatigue, behavioral habits, and psychological self-regulation) as moderators of seasonality in sleep timing and chronotype.MethodsA sample of 162 young adults (76% females; mean age: females 23.4 years, males 24.3 years) participated in a prospective study across three seasons (September, December, March) in Tromsø/Norway at 69°39′N. Sleep diary and sleep/health-related questionnaire data were collected at each time-point.ResultsSleep timing and chronotype were delayed during the dark period (December) compared with brighter photoperiods (September and March). Comparable effects were observed for insomnia, fatigue, mood (depression and anxiety), subjective health complaints, physical activity, and school-related stress. Most importantly, depression and fatigue moderated the degree of seasonal shifting in sleep timing, whereas the other self-regulation indicators did not (ie eating habits, physical activity, and psychological self-regulation).ConclusionSeasonality in sleep timing and chronotype was confirmed, and it seems that depressive symptoms during the dark period exacerbate phase-shifting problems for people living in sub-Arctic regions.     

Detecting chronotype differences associated to latitude: a comparison between Horne--Östberg and Munich Chronotype questionnaires

Background: Chronotype, phase preference to perform activities during a 24-hour day, represents distinct circadian temporal organization of living organisms. Morning and evening types can be identified by questionnaires such as Horne and Östberg (HO) and Munich Chronotype Questionnaire (MCTQ). Environmental factors, such as different light–dark cycles experienced at different latitudes, interact with the organisms’ circadian timekeeping system. Therefore, chronotype is expected to vary as a result of different geographical locations.

Aim: To identify differences in chronotype distribution in populations of two Brazilian cities, Natal and Sao Paulo, located at different latitudes.

Subjects and methods: Two specific questionnaires, the Horne and Östberg Questionnaire (HO) and the Munich Chronotype Questionnaire (MCTQ), were used to identify chronotypes of undergraduate students from São Paulo and Natal.

Results: The comparison of the curve distributions of HO and MCTQ scores between both cities allowed one to observe that, while HO curves of São Paulo and Natal overlapped, MCTQ curves showed a clear shift towards eveningness in São Paulo.

Conclusion: This experiment confirmed results from previous studies that the farther away from the equator, the longer the delay of the sleep phase. It was also concluded that MCTQ is better at detecting this phenomenon.     

Daytime sleepiness during transition into daylight saving time in adolescents: Are owls higher at risk?

BackgroundIndividuals differ in their biological rhythms and preferences for time of day. Here, we looked at the transition into daylight saving time (DST) in adolescents. As adolescents tend to be evening types, one may expect that they suffer from a transition into DST.MethodsTo assess these changes, we measured daytime sleepiness and morningness–eveningness preference (CSM score) in adolescents.ResultsDaytime sleepiness correlated with age and CSM score. Older pupils and evening types showed a higher sleepiness. Daytime sleepiness was higher after the transition until the third week after. Older pupils and pupils scoring higher on eveningness reported higher daytime sleepiness after the transition, suggesting that these pupils suffer most from the change. Using cut-off scores for larks and owls, we found that owls showed higher sleepiness than larks.ConclusionAs one consequence, class and school performance tests should not take place in the first week(s) after the transition into DST.     

Sleep quality, chronotypes and preferential timing of attacks in migraine without aura

Clinical observations show that migraine attacks have a seasonal, menstrual and circadian timing, suggesting a role of chronobiological mechanisms and their alterations in the disease, but little experimental data exists about this issue. The aim of this study was to estimate sleep quality chronotypes and the possible circadian timing of attacks in migraneurs. One hundred patients suffering from migraine without aura according to the IHS criteria (2004), and 30 controls were enrolled. Morning and evening type subjects were more represented in migraine patients than in controls and showed a tendency towards worse sleep quality and higher disability. Forty–two percent of migraineurs presented more than 75% of their attacks at night. Morning and evening types rather than intermediate and differences between real and preferred times may represent stressors that can worsen the disease. A preferential timing for occurrence of migraine attacks during the night and early morning hours was documented.     

Evaluating causal associations between chronotype and fatty acids and between fatty acids and type 2 diabetes: A Mendelian randomization study

Background and aimsPreference for activity in the morning or evening (chronotype) may impact type 2 diabetes (T2D) risk factors. Our objective was to use Mendelian randomization (MR) to evaluate whether there are causal links between chronotype and one potential T2D risk factor, total fatty acids (TOTFA), and between TOTFA and T2D.Methods and resultsWe estimated the causal effect of: 1) morning chronotype on TOTFA; and 2) higher TOTFA on T2D. We found that: a) morning compared to evening chronotype was associated with lower TOTFA levels (inverse-weighted variance (IVW) estimate −0.21; 95% CI −0.38, −0.03; raw P = 0.02; FDR-corrected P 0.04) and b) elevated TOTFA levels were protective against T2D (IVW estimate −0.23; 95% CI −0.41, −0.05; raw P = 0.01; FDR-corrected P = 0.03). Based on this finding, we further hypothesized that healthy fats would show a similar pattern and performed MR of a) morning chronotype on omega-3 (Omega-3), monounsaturated (MUFA), and polyunsaturated (PUFA) fatty acids; and b) MR of each of these fat types on T2D. We observed the same mediating-type pattern for chronotype, MUFA, and T2D as we had for chronotype, TOTFA, and T2D, and morning chronotype was associated with lower Omega-3.ConclusionOur findings provide suggestive, new information about relationships among chronotype, TOTFA, and T2D and about chronotype as a factor influencing Omega-3, MUFA, and TOTFA levels. In addition, we validated previous knowledge about MUFA and T2D. Morning chronotypes may predispose towards lower levels of TOTFA and some healthy fats, whereas higher levels of TOTFA and MUFA may protect against T2D.