Calculating the Social Rhythm Metric (SRM) and Examining Its Use in Interpersonal Social Rhythm Therapy (IPSRT) in a Healthy Population Study

Behavioral-Social Rhythms and Cardiovascular Disease Risk in Retired Night Shift Workers and Retired Day Workers

OBJECTIVE

Stability in the timing of key daily routine behaviors such as working/doing housework, sleeping, eating, and engaging in social interactions (i.e., behavioral-social rhythms) contributes to health. This study examined whether behavioral-social rhythms were associated with cardiovascular disease (CVD) risk factors in retired night shift workers and retired day workers and explored whether past night shift work exposure moderated this association.

METHODS

A total of 154 retired older adults participated in this study. Multiple logistic regression models were used to examine associations between behavioral-social rhythms and CVD risk factors. Independent variables included Social Rhythm Metric (SRM)-5 score and actigraphy rest-activity rhythm intradaily variability (IV) and interdaily stability (IS). Dependent variables were metabolic syndrome prevalence and its five individual components.

RESULTS

More regular behavioral-social rhythms were associated with lower odds of prevalent metabolic syndrome (SRM: odds ratio [OR] = 0.57, 95% confidence interval [CI] = 0.35-0.88; IV: OR = 4.00, 95% CI = 1.86-8.58; IS: OR = 0.42, 95% CI = 0.24-0.73) and two of its individual components: body mass index (SRM: OR = 0.56, 95% CI = 0.37-0.85; IV: OR = 2.84, 95% CI = 1.59-5.07; IS: OR = 0.42, 95% CI = 0.26-0.68) and high-density lipoprotein cholesterol (SRM: OR = 0.49, 95% CI = 0.30-0.80; IV: OR = 2.49, 95% CI = 1.25-4.96; IS: OR = 0.35, 95% CI = 0.19-0.66). Past shift work history did not moderate the association between behavioral-social rhythms and metabolic syndrome.

CONCLUSIONS

Behavioral-social rhythms were related to CVD risk factors in retired adults regardless of prior night shift work exposure. Older retired workers may benefit from education and interventions aiming to increase behavioral-social rhythm regularity.

Chronotype and Time of Day Effects on a Famous Face Recognition Task with Dynamic Stimuli

Chronotype and Time of Day (ToD) can modulate several aspects of cognitive performance. However, there is limited evidence about the effect of these variables on face recognition performance, so the aim of the present study is to investigate this influence. For this, 274 participants (82.5% females; age 18-49 years old, mean = 27.2, SD = 1.82) were shown 20 short videoclips, each gradually morphing from a general identity unfamiliar face to a famous face. Participants should press the spacebar to stop each video as soon as they could identify the famous face, and then provide the name or an unequivocal description of the person. Analysis of response times (RT) showed that evening-types recognised the faces faster than morning-types. Considering different ToD windows, the effect of chronotype was only significant in the 13h-17h and in the 21h-6h time-windows. Altogether, results suggest an advantage of evening-types on famous face recognition using dynamic stimuli with morning-types, being particularly slower during their non-optimal period.

Does the Internet Bring People Closer Together or Further Apart? The Impact of Internet Usage on Interpersonal Communications

The complementarity interference (CI) model suggests that the Internet may either inhibit or facilitate interpersonal communications. This paper empirically examines the impact of Internet usage on interpersonal interactions, using a micro dataset from China to answer whether the Internet brings people closer together or further apart. The empirical results demonstrate, first, that Internet usage significantly increases both the time and frequency of people’s communications with their family and friends, rather than causing them to feel more disconnected and isolated. Holding other factors constant, for each one-standard-deviation increase in Internet usage, weekly communications with family members increases by an average of 102.150 min, while there is an average increase of 54.838 min in interactions with friends. These findings as to its positive effects are robust when using other regression models and interpersonal contact measures, as well as the instrumental variable method. Second, Internet usage also contributes to decreased loneliness; it exerts this effect primarily by improving people’s interactions with their family members. However, communications with friends do not significantly mediate such impacts. Third, the positive role of Internet usage on communications is more prominent for people with more frequent online socialization and self-presentation, better online skills, younger age, higher educational level, and who are living in urban areas. In addition, the beneficial effects of Internet usage are larger for communications with family members in the case of migrants. Therefore, in the context of the rapid development of information technology, the network infrastructure should be improved to make better use of the Internet to facilitate interpersonal communications and promote people’s wellness.

Disrupted daily routines mediate the socioeconomic gradient of depression amid public health crises: A repeated cross-sectional study

OBJECTIVE

There is a socioeconomic gradient to depression risks, with more pronounced inequality amid macroenvironmental potential traumatic events. Between mid-2019 and mid-2020, the Hong Kong population experienced drastic societal changes, including the escalating civil unrest and the COVID-19 pandemic. We examined the change of the socioeconomic gradient in depression and the potential intermediary role of daily routine disruptions.

METHOD

We conducted repeated territory-wide telephone surveys in July 2019 and July 2020 with 1112 and 2034 population-representative Cantonese-speaking Hong Kong citizens above 15 years old, respectively. Stratified by year, we examined the association between socioeconomic indicators (education attainment, household income, employment status and marital status) and probable depression (nine-item Patient Health Questionnaire [PHQ-9] ⩾ 10) using logistic regression. Differences in the socioeconomic gradient between 2019 and 2020 were tested. Finally, we performed a path analysis to test for the mediating role of daily routine disruptions.

RESULTS

Logistic regression showed that higher education attainment in 2019 and being married in 2020 were protective against probable depression. Interaction analysis showed that the inverse association of higher education attainment with probable depression attenuated in 2020 but that of being married increased. Path analysis showed that the mediated effects through daily routine disruptions accounted for 95.9% of the socioeconomic gradient of probable depression in 2020, compared with 13.1% in 2019.

CONCLUSION

From July 2019 to July 2020, the mediating role of daily routine disruptions in the socioeconomic gradient of depression in Hong Kong increased. It is thus implied that infection control measures should consider the relevant potential mental health impacts accordingly.

Work Habit-Related Sleep Debt; Insights From Factor Identification Analysis of Actigraphy Data

The present study investigates the factors of “Weekday sleep debt (WSD)” by comparing activity data collected from persons with and without WSD. Since it has been reported that the amount of sleep debt as well the difference between the social clock and the biological clock is associated with WSD, specifying the factors of WSD other than chronotype may contribute to sleep debt prevention. We recruited 324 healthy male employees working at the same company and collected their 1-week wrist actigraphy data and answers to questionnaires. Because 106 participants were excluded due to measurement failure of the actigraphy data, the remaining 218 participants were included in the analysis. All participants were classified into WSD or non-WSD groups, in which persons had WDS if the difference between their weekend sleep duration and the mean weekday sleep duration was more than 120 min. We evaluated multiple measurements derived from the collected actigraphy data and trained a classifier that predicts the presence of WSD using these measurements. A support vector machine (SVM) was adopted as the classifier. In addition, to evaluate the contribution of each indicator to WSD, permutation feature importance was calculated based on the trained classifier. Our analysis results showed significant importance of the following three out of the tested 32 factors: (1) WSD was significantly related to persons with evening tendency. (2) Daily activity rhythms and sleep were less stable in the WSD group than in the non-WSD group. (3) A specific day of the week had the highest importance in our data, suggesting that work habit contributes to WSD. These findings indicate some WSD factors: evening chronotype, instability of the daily activity rhythm, and differences in work habits on the specific day of the week. Thus, it is necessary to evaluate the rhythms of diurnal activities as well as sleep conditions to identify the WSD factors. In particular, the diurnal activity rhythm influences WSD. It is suggested that proper management of activity rhythm may contribute to the prevention of sleep debt.

How do stress, sleep quality, and chronotype associate with clinically significant depressive symptoms? A study of young male military recruits in compulsory service

OBJECTIVE

Although studies have shown an association between poor sleep and chronotype with psychiatric problems in young adults, few have focused on identifying multiple concomitant risk factors.

METHODS

We assessed depressive symptoms (Beck Depression Inventory [BDI]), circadian typology (Morningness-Eveningness Questionnaire [MEQ]), sleep quality (Pittsburgh Sleep Quality Index [PSQI]), perceived stress (Perceived Stress Scale [PSS]), social rhythm (Social Rhythm Metrics [SRM]), and salivary cortisol (morning, evening and night, n=37) in 236 men (all 18 years old). Separate analyses were conducted to understand how each PSQI domain was associated with depressive symptoms.

RESULTS

Depressive symptoms were more prevalent in individuals with higher perceived stress (prevalence ratio [PR] = 6.429, p < 0.001), evening types (PR = 2.58, p < 0.001) and poor sleepers (PR = 1.808, p = 0.046). Multivariate modeling showed that these three variables were independently associated with depressive symptoms (all p < 0.05). The PSQI items subjective sleep quality and sleep disturbances were significantly more prevalent in individuals with depressive symptoms (PR = 2.210, p = 0.009 and PR = 2.198, p = 0.008). Lower levels of morning cortisol were significantly associated with higher depressive scores (r = -0.335; p = 0.043).

CONCLUSION

It is important to evaluate multiple factors related to sleep and chronotype in youth depression studies, since this can provide important tools for comprehending and managing mental health problems.

Social rhythm regularity moderates the relationship between sleep disruption and depressive symptoms in veterans with post-traumatic stress disorder and major depressive disorder

Approximately 50% to 80% of individuals with posttraumatic stress disorder (PTSD) also meet criteria for major depressive disorder (MDD). Sleep disturbance is a major concern in both PTSD and MDD, and is associated with poor treatment response, poor functional outcome and increased suicide risk. Social rhythm regularity, or the consistency of daily habitual behaviors, is theoretically linked to circadian rhythms and may be disturbed in both PTSD and MDD. The present study examined the relationship between social rhythm regularity, sleep disruption and MDD and PTSD symptoms in a sample of veterans with comorbid PTSD and MDD. Baseline data were obtained from 56 male veterans who met DSM-IV criteria for PTSD and MDD. Veterans completed the Social Rhythm Metric (SRM), a self-report questionnaire that assesses the regularity of routines by determining how regularly individuals completed 17 different types of activities. In a linear regression model, increased minutes awake after sleep onset (WASO) was a significant predictor of increased depression scores on the Hamilton Rating Scale for Depression (p < .05). SRM scores did not significantly predict depressive symptoms, however the interaction of WASO and SRM significantly predicted depressive symptoms (p = <.05), with significant relationships found at SRM scores less than 3.62. Neither minutes awake after sleep onset, SRM scores, nor their interaction was associated with PTSD symptom severity. Social and possibly circadian rhythm regularity may represent a risk or resilience factor for individuals with comorbid PTSD and MDD. Findings highlight the importance of exploring the interactions of sleep and social/circadian rhythms in depression in order to inform continued treatment development.

Biological dysrhythm in remitted bipolar I disorder

BACKGROUND

Recent treatment guidelines support treatment of biological rhythm abnormalities as a part of treatment of bipolar disorder, but still, literature examining various domains (Sleep, Activity, Social, and Eating) of biological rhythm and its clinical predictors are less.

OBJECTIVES

The main aim of our study is to compare various domains of biological rhythm among remitted bipolar I subjects and healthy controls. We also explored for any association between clinical variables and biological rhythm among bipolar subjects.

METHODS

40 subjects with Bipolar I disorder and 40 healthy controls who met inclusion and exclusion criteria were recruited for the study. Diagnoses were ascertained by a qualified psychiatrist using MINI 5.0. Sociodemographic details, biological rhythm (BRIAN-Biological Rhythm Interview of assessment in Neuropsychiatry) and Sleep functioning (PSQI- Pittsburgh Sleep Quality Index) were assessed in all subjects.

RESULTS

Mean age of the Bipolar subjects and controls were 41.25±11.84years and 38.25±11.25 years respectively. Bipolar subjects experienced more biological rhythm disturbance when compared to healthy controls (total BRIAN score being 34.25±9.36 vs 28.2±6.53) (p=0.002). Subsyndromal depressive symptoms (HDRS) had significant positive correlation with BRIAN global scores(r=0.368, p=0.02). Linear regression analysis showed that number of episodes which required hospitalization (β=0.601, t=3.106, P=0.004), PSQI (β=0.394, t=2.609, p=0.014), HDRS (β=0.376, t=2.34, t=0.036) explained 31% of variance in BRIAN scores in remitted bipolar subjects.

CONCLUSION

Biological rhythm disturbances seem to persist even after clinical remission of bipolar illness. More studies to look into the impact of subsyndromal depressive symptoms on biological rhythm are needed.

The Bidirectional Relationship between Positive Mental Health and Social Rhythm in College Students:A Three-Year Longitudinal Study

Social rhythm refers to the general regularity of engaging in basic social activities during the week, and was found to be associated with individuals' positive mental health. The present study investigated the relationship between social rhythm and emotional well-being in a cohort of 2,031 college students over 3 years with a cross-lagged longitudinal panel design. Results revealed that regularity of social rhythm positively predicted emotional well-being in the following year, and vice versa, when the level of both factors in the previous year was controlled. Our study provides evidence of a longitudinal positive reciprocal relationship between social rhythm and positive mental health in younger adult populations.

Automatic detection of social rhythms in bipolar disorder

OBJECTIVE

To evaluate the feasibility of automatically assessing the Social Rhythm Metric (SRM), a clinically-validated marker of stability and rhythmicity for individuals with bipolar disorder (BD), using passively-sensed data from smartphones.

METHODS

Seven patients with BD used smartphones for 4 weeks passively collecting sensor data including accelerometer, microphone, location, and communication information to infer behavioral and contextual patterns. Participants also completed SRM entries using a smartphone app.

RESULTS

We found that automated sensing can be used to infer the SRM score. Using location, distance traveled, conversation frequency, and non-stationary duration as inputs, our generalized model achieves root-mean-square-error of 1.40, a reasonable performance given the range of SRM score (0-7). Personalized models further improve performance with mean root-mean-square-error of 0.92 across users. Classifiers using sensor streams can predict stable (SRM score ≥3.5) and unstable (SRM score <3.5) states with high accuracy (precision: 0.85 and recall: 0.86).

CONCLUSIONS

Automatic smartphone sensing is a feasible approach for inferring rhythmicity, a key marker of wellbeing for individuals with BD.

Social Rhythm and Mental Health: A Cross-Cultural Comparison

Background

Social rhythm refers to the regularity with which one engages in social activities throughout the week, and has established links with bipolar disorder, as well as some links with depression and anxiety. The aim of the present study is to examine social rhythm and its relationship to various aspects of health, including physical health, negative mental health, and positive mental health.

Method

Questionnaire data were obtained from a large-scale multi-national sample of 8095 representative participants from the U.S., Russia, and Germany.

Results

Results indicated that social rhythm irregularity is related to increased reporting of health problems, depression, anxiety, and stress. In contrast, greater regularity is related to better overall health state, life satisfaction, and positive mental health. The effects are generally small in size, but hold even when controlling for gender, marital status, education, income, country, and social support. Further, social rhythm means differ across Russia, the U.S., and Germany. Relationships with mental health are present in all three countries, but differ in magnitude.

Conclusions

Social rhythm irregularity is related to mental health in Russia, the U.S., and Germany.