Association between smoking and central sensitization pain: a web-based cross-sectional study.

PURPOSE: This study aimed to investigate whether smoking is an independent risk factor for central sensitization syndrome (CSS) in individuals with pain as measured by the Central Sensitization Inventory (CSI). METHODS: In 2020, we conducted an Internet survey targeting 2000 ordinary residents of Japan (aged 20-69 years) who had pain symptoms from October to November 2020. A multiple regression analysis was performed on the association between smoking status (nonsmokers and current smokers; Brinkman index) and CSI values. Moreover, compared to nonsmokers, the relative risk (RR) of the CSI cut-off score of 40 points or higher among current smokers was calculated using a modified Poisson regression model. Covariates included age, sex, body mass index, marital status, equivalized income, exercise habits, history of hypertension, history of hyperlipidemia, history of diabetes, pain chronicity, and Pain Catastrophizing Scale score. RESULTS: This study analyzed 1,822 individuals (1,041 men and 781 women). Among those experiencing pain, current smoking was associated with the increase in CSI values (ß = 0.07). The Brinkman index was also significantly associated with the increase in CSI values (ß = 0.06). Current smoking also increased the risk of being over the CSI cut-off score, with a relative risk (RR) of 1.29 (95% confidence intervals, 1.04-1.60). Younger age, being women, experiencing chronic pain, and higher pain catastrophizing thinking were also significantly associated with increased CSS severity, independent of smoking status. CONCLUSION: Smoking is an independent risk factor for CSS. This indicates that smoking may be an important factor in the management of central pain disorders.

Effect of repeated transforaminal epidural low-dose dexamethasone injections on glucose profiles of diabetic and non-diabetic patients with low back pain.

PURPOSE: We aimed to investigate the effect of repeated transforaminal epidural low-dose dexamethasone injections on glucose profiles and pituitary-adrenal axis functions of diabetic and non-diabetic patients with low back pain. METHODS: A total of 28 patients (ten diabetic [DM group] and 18 non-diabetic patients [non-DM group]) with low back pain were followed-up. Transforaminal epidural low-dose dexamethasone (1.65 mg) injections were repeated every 7-14 days for 8 weeks. Fasting blood sugar (FBS), hemoglobin A1c (HbA1c), morning plasma adrenocorticotropin (ACTH), and cortisol levels were measured at baseline and during the 8-week follow-up period. RESULTS: There were no significant changes in FBS and HbA1c levels between baseline and 8-week follow-up period in both DM and non-DM groups (difference in FBS [95% confidence Interval, CI]: - 0.6 mg/dL [- 6.4, 5.1], p = 0.83 in the non-DM group, - 0.2 mg/dL [- 26.2, 25.8], p = 0.99 in the DM group; difference in HbA1c [95% CI] - 0.02% [- 0.1, 0.1], p = 0.69 in the non-DM group, 0.04% [- 0.3, 0.4], p = 0.79 in the DM group). There were no significant longitudinal changes in ACTH and cortisol levels (ACTH, p = 0.38 [baseline vs. 8 week], p = 0.58 [non-DM vs. DM]; cortisol, p = 0.52 [baseline vs. 8 week], p = 0.90 [non-DM vs. DM]). CONCLUSIONS: Repeated transforaminal epidural low-dose dexamethasone injections provided no significant elevations in blood glucose or suppression of the pituitary-adrenal axis for two months from the first injection in both diabetic and non-diabetic patients. Our results indicate the intermediate-term safety of repeated transforaminal epidural low-dose dexamethasone injections with regard to the effect on glucose profile and pituitary-adrenal axis functions.

Effects of Thoracic Epidural Anesthesia on Systemic and Local Inflammatory Responses in Patients Undergoing Lung Cancer Surgery: A Randomized Controlled Trial.

OBJECTIVE: Inflammatory responses play major roles in the development of acute lung injury following lung cancer surgery. The authors tested the hypothesis that thoracic epidural anesthesia (TEA) during surgery could attenuate both systemic and local inflammatory cytokine productions in patients undergoing lung cancer surgery. DESIGN: A prospective randomized controlled trial. SETTING: At Keio University Hospital, Tokyo, Japan. PARTICIPANTS: Patients scheduled for lung cancer surgery. INTERVENTIONS: Sixty patients were randomly allocated into two groups (n = 30 each group): the epidural group (group E), in which anesthesia was maintained with propofol, fentanyl, rocuronium, and epidural anesthesia with 0.25% levobupivacaine; or the remifentanil group (group R), in which a remifentanil infusion was used as a potent analgesia instead of epidural anesthesia. MEASUREMENTS AND MAIN RESULTS: The lung epithelial lining fluid (ELF) and blood sampling were collected prior to one-lung ventilation (OLV) initiation (T1) and at 30 minutes after the end of OLV (T2). The concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 in the ELF at T2 were increased significantly compared with those at T1 in both groups. The ELF concentration of IL-6 in group E was significantly lower than that in group R at T2 (median [interquartile range]: 39.7 [13.8-80.2] versus 76.1 [44.9-138.2], p = 0.008). Plasma IL-6 concentrations at T2, which increased in comparison to that at T1, were not significantly different between the two groups. The plasma concentrations of TNF-α did not change in both groups. CONCLUSIONS: This randomized clinical trial suggested that TEA could attenuate local inflammatory responses in the lungs during lung cancer surgery.

Negative effect of anger on chronic pain intensity is modified by multiple mood states other than anger: A large population-based cross-sectional study in Japan.

OBJECTIVES: To investigate whether mood states other than anger can modify the association between anger and pain intensity in individuals with chronic pain. METHODS: We analysed 22,059 participants with chronic pain, including 214 participants with rheumatoid arthritis (RA), who completed a questionnaire. The Profile of Mood States short form (POMS-SF) was used to assess six dimensions of mood states (anger-hostility, tension-anxiety, depression-dejection, confusion, fatigue, and vigour). A numerical rating scale (NRS) assessed pain intensity. We examined the association between anger-hostility and the NRS and the relationship between POMS-SF components. Moderation analyses were used to investigate whether the five mood states other than anger-hostility modified the effect of anger-hostility on the NRS. RESULTS: Anger-hostility contributed to pain intensity. Although increased mood states other than vigour were associated with increased pain intensity, these increased mood states appeared to suppress the effect of anger-hostility on pain intensity. Increased vigour was associated with decreased pain intensity and increased the effect of anger-hostility on pain intensity. CONCLUSIONS: Mood states other than anger may influence the association between anger and pain intensity in individuals with chronic pain. It is important to focus on complicated mood states and anger in individuals with chronic pain, including RA.

Reorganization of functional brain network architecture in chronic osteoarthritis pain.

Osteoarthritis (OA) manifests with chronic pain, motor impairment, and proprioceptive changes. However, the role of the brain in the disease is largely unknown. Here, we studied brain networks using the mathematical properties of graphs in a large sample of knee and hip OA (KOA, n = 91; HOA, n = 23) patients. We used a robust validation strategy by subdividing the KOA data into discovery and testing groups and tested the generalizability of our findings in HOA. Despite brain global topological properties being conserved in OA, we show there is a network wide pattern of reorganization that can be captured at the subject-level by a single measure, the hub disruption index. We localized reorganization patterns and uncovered a shift in the hierarchy of network hubs in OA: primary sensory and motor regions and parahippocampal gyrus behave as hubs and insular cortex loses its central placement. At an intermediate level of network structure, frontoparietal and cingulo-opercular modules showed preferential reorganization. We examined the association between network properties and clinical correlates: global disruption indices and isolated degree properties did not reflect clinical parameters; however, by modeling whole brain nodal degree properties, we identified a distributed set of regions that reliably predicted pain intensity in KOA and generalized to hip OA. Together, our findings reveal that while conserving global topological properties, brain network architecture reorganizes in OA, at both global and local scale. Network connectivity related to OA pain intensity is dissociated from the major hub disruptions, challenging the extent of dependence of OA pain on nociceptive signaling.

Structural MRI Analysis of Chronic Pain Patients Following Interdisciplinary Treatment Shows Changes in Brain Volume and Opiate-Dependent Reorganization of the Amygdala and Hippocampus.

OBJECTIVE: The present study examined pre- to post-treatment changes in volumes for brain structures known to be associated with pain processing (thalamus, caudate, putamen, pallidum, hippocampus, amygdala, and accumbens) following an interdisciplinary pain management program. DESIGN: Twenty-one patients participating in a four-week interdisciplinary pain management program completed the study. The program consisted of individual and group therapies with the following disciplines: physical therapy, occupational therapy, pain psychology, biofeedback/relaxation training, nursing lectures, and medical management. All patients underwent functional magnetic resonance imaging of the brain before the start and at completion of the program. They also completed standard outcome measures assessing pain, symptoms of central sensitization, disability, mood, coping, pain acceptance, and impressions of change. RESULTS: Our results showed a significant increase in total brain volume, as well as increased volumes in the thalamus, hippocampus, and amygdala. As expected, we also found significant improvements in our standard outcome measures. The majority of patients rated themselves as much or very much improved. The increase in volume in the hippocampus was significantly associated with patient perceptions of change. However, the correlations were in the unexpected direction, such that greater increases in hippocampal volume were associated with perceptions of less improvement. Further exploratory analyses comparing patients by their opioid use status (use vs no use) showed differential program effects on volume increases in the hippocampus and amygdala. CONCLUSIONS: These findings show that a four-week interdisciplinary pain management program resulted in changes in the brain, which adds objective findings further demonstrating program efficacy.

Pain medications during pregnancy: data from the Japan environment and children's study.

PURPOSE: Analgesic medication epidemic during pregnancy is an important issue in Western countries. However, no large epidemiological study involving pregnant women with pain and their medication use has been conducted in Japan. This study examined the current situation of medication use for non-cancer pain during the perinatal period in Japan using national cohort data. METHODS: We analyzed 94,649 pregnant women who completed a self-report questionnaire investigating bodily pain and an interview-based medication use survey. Medication use before and during pregnancy and new medication administration/discontinuation during pregnancy were compared between women with and without pain during pregnancy using multivariable covariance analysis. RESULTS: Mild pain was reported by 50.4% of pregnant women in the first trimester (survey 1) and 61.8% in the second/third trimester (survey 2). Moderate-to-severe pain was reported by 15.4% of women in survey 1 and 22.4% in survey 2. In survey 1, 6.2% of women used prescribed analgesics and 1.6% used over-the-counter analgesics. In survey 2, prescribed and over the counter analgesics were used by 12.2% and 0.8% of women, respectively. Other pain-related medications were rarely used (< 1.0%). Pregnant women with moderate-to-severe pain showed a lower proportion of discontinuation of analgesics and a higher proportion of new administration of prescription and transdermal analgesics compared with those without pain. CONCLUSIONS: Although a large proportion of pregnant women experience pain, medication use for pain during pregnancy is low in Japan compared with Western countries (50-60%). Adequate treatment or support may be necessary for pregnant women experiencing pain in Japan.

Smoking is associated with greater pain intensity and pain-related occupational disability in Japanese workers.

PURPOSE: Pain symptom, such as that caused by musculoskeletal disorders, is a major cause of occupational disability. As nicotine intake from smoking increases pain sensitivity, smokers may experience stronger pain and be more likely to experience pain-related disability than non-smokers. The study aim was to examine whether smoking was associated with pain-related occupational disability via pain intensity. METHODS: Participants were 1189 workers with pain aged 20-74 years in Japan. Participants completed a self-report questionnaire, which included a question to measure pain-related occupational disability with ordinal-option: (1) without pain-related disability, (2) pain-related presenteeism, and (3) pain-related absenteeism. An ordinal logistic regression model was used to calculate multivariable-adjusted proportional odds ratios (OR) with 95% confidence intervals (CI) for the prevalence of pain-related occupational disability according to smoking status. A multiple mediation analysis was also conducted to assess whether pain sensitivity mediated the association between smoking and pain-related occupational disability. Adjusted variables were demographic variables, socioeconomic status, work-related psychosocial factors, general psychological factors, and pain duration. RESULTS: Current smoking and pain were associated with pain-related occupational disability compared with non-smoking and pain (multivariable OR 1.78; 95% CI 1.26-2.52). Greater pain intensity partially mediated the association of current smoking and pain with pain-related occupational disability. The mediation rate (indirect/total effect) was 25%. CONCLUSION: Smoking and pain were associated with pain-related occupational disability, partially through greater pain intensity, among Japanese workers.

Fear-avoidance beliefs are independently associated with the prevalence of chronic pain in Japanese workers.

PURPOSE: Pain is a global public health problem with implications for both personal and social heath. Fear-avoidance beliefs (FABs) have been demonstrated to negatively impact and prolong pain in many Western countries, but little is known about the association between FABs and chronic pain (CP) in Asian countries, including Japan. We examined the relationship between FABs and CP in Japanese white-collar workers, a growing population with a high prevalence of CP. METHODS: Questionnaires and company records were used to gather data from 433 Japanese white-collar workers. Data were related to experience of pain, participant sociodemographic/health/lifestyle characteristics, fear-avoidance beliefs [Tampa Scale for Kinesiophobia (TSK)], work-related psychosocial factors (Brief Job Stress Questionnaire), and depressive illness [Psychological Distress Scale (K6)]. Analysis of covariance and multilevel logistic regression modeling were used to analyze associations between the data while controlling for factors known to influence CP prevalence. RESULTS: Prevalence rate of CP was 11.1% (48 of 433 persons). Adjusted odds ratios for participants with CP significantly increased in participants with high TSK scores, even after adjusting for factors known to influence CP prevalence. CONCLUSION: We found a significant association between high TSK scores and CP in Japanese white-collar workers when controlling for other known factors that influence CP such as work-related psychosocial characteristics and depressive conditions. This finding suggests that FABs are independently associated with prevalence of CP.

Involvement of mesolimbic dopaminergic network in neuropathic pain relief by treadmill exercise: A study for specific neural control with Gi-DREADD in mice.

BACKGROUND: Exercise alleviates pain and it is a central component of treatment strategy for chronic pain in clinical setting. However, little is known about mechanism of this exercise-induced hypoalgesia. The mesolimbic dopaminergic network plays a role in positive emotions to rewards including motivation and pleasure. Pain negatively modulates these emotions, but appropriate exercise is considered to activate the dopaminergic network. We investigated possible involvement of this network as a mechanism of exercise-induced hypoalgesia. METHODS: In the present study, we developed a protocol of treadmill exercise, which was able to recover pain threshold under partial sciatic nerve ligation in mice, and investigated involvement of the dopaminergic reward network in exercise-induced hypoalgesia. To temporally suppress a neural activation during exercise, a genetically modified inhibitory G-protein-coupled receptor, hM4Di, was specifically expressed on dopaminergic pathway from the ventral tegmental area to the nucleus accumbens. RESULTS: The chemogenetic-specific neural suppression by Gi-DREADD system dramatically offset the effect of exercise-induced hypoalgesia in transgenic mice with hM4Di expressed on the ventral tegmental area dopamine neurons. Additionally, anti-exercise-induced hypoalgesia effect was significantly observed under the suppression of neurons projecting out of the ventral tegmental area to the nucleus accumbens as well. CONCLUSION: Our findings suggest that the dopaminergic pathway from the ventral tegmental area to the nucleus accumbens is involved in the anti-nociception under low-intensity exercise under a neuropathic pain-like state.

Exercise effect on pain is associated with negative and positive affective components: A large-scale internet-based cross-sectional study in Japan.

Pain is a global health problem that leads to sedentary behavior and tends to cause negative emotion. In contrast, exercise is widely recommended for a health promotion, while pain often worsens with physical activity. Although exercise therapy is often prescribed to people with pain, the mechanisms of exercise effect on pain remains unclear. In this study, we tried to identify a universal association factor between regular exercise and pain intensity utilizing a cross-sectional web-based survey involving 52,353 adult participants from a large national study conducted in Japan. Using principal component analysis, we uncovered a mediation model of exercise effect on pain through psychological components. Analyses were performed in half of the population with pain (n = 20,330) and validated in the other half (n = 20,330), and showed that high-frequency exercise had a significant association with reduction in pain intensity. We also found Negative Affect and Vigor, two psychological components, are fully associating the exercise effect on pain (indirect effect = - 0.032, p < 0.001; association proportion = 0.99) with a dose-dependent response corresponding to the frequency of exercise. These findings were successfully validated (indirect effect of high-frequency exercise = - 0.028, p < 0.001; association proportion = 0.85). Moreover, these findings were also identified in subpopulation analyses of people with low back, neck, knee pain, and the tendency of the exercise effect on pain was increased with older people. In conclusion, the effect of exercise on pain is associated with psychological components and these association effects increased in parallel with the frequency of exercise habit regardless pain location.

Influence of exercise on pain is associated with resting-state functional connections: A cross-sectional functional brain imaging study.

Exercise is associated with lower prevalence and severity of pain, and is widely recommended for pain management. However, the mechanisms the exercise effect on pain remain unclear. In this study, we examined the association of exercise with pain and aimed to identify its neurobiological mediators. We utilized a baseline data of a clinical trial for people with low back pain. Participants reported pain intensity and exercise habit, as well as pain-related psychological and emotional assessments. We also obtained brain imaging data using a resting-state functional MRI and performed mediation analyses to identify brain regions mediating the exercise effect on pain. Forty-five people with low back pain (mean pain intensity = 59.6 and mean duration = 9.9 weeks) were included in this study. Participants with an exercise habit (n = 29) showed significant less pain compared to those without an exercise habit (n = 16). Mediation analysis using resting-state functional connectivity identified the left thalamus, right amygdala, and medial prefrontal cortex as statistical mediators of the exercise effect on pain (indirect effect = -0.460, 95% confidence interval = -0.767 to -0.153). In conclusion, our findings suggest that brain function of the specific regions is probably a neuro-mechanism of exercise alleviating pain.

Decreased Interoceptive Awareness as a Risk Factor for Moderate to Severe Pain in Japanese Full-Time Workers: A Longitudinal Cohort Study.

Interoceptive awareness, the conscious perception of internal bodily states, is a key construct of mind-body interaction. Decreases in interoceptive awareness, as measured by the Multidimensional Assessment of Interoceptive Awareness (MAIA), are found in chronic pain patients. In this study, we explored whether a specific aspect of interoceptive awareness is a risk for the onset and chronicity of pain. A longitudinal cohort study was conducted in 2018 and 2020 among a sample of full-time workers in an industrial manufacturing company in Japan. Participants completed a questionnaire on pain intensity, MAIA, exercise habits, kinesiophobia, psychological distress and work stress. Principal component analyses using the MAIA identified two principal components: self-control and emotional stability. Low emotional stability was associated with the prevalence of moderate to severe pain in 2020 among people with mild or no pain in 2018 (p < 0.01). Lack of exercise habits were associated with the prevalence of moderate to severe pain in 2020 among people with pain in 2018 (p < 0.01). Furthermore, exercise habits were associated with reduction in kinesiophobia among people with moderate to severe pain in 2018 (p = 0.047). Overall, these findings indicate that low emotional stability may be a risk for the onset of moderate to severe pain; lack of exercise habits may sustain kinesiophobia and be a risk for the chronicity of pain.

Impact of continued mindfulness practice on resilience and well-being in mindfulness-based intervention graduates during the COVID-19 pandemic: A cross-sectional study.

Aim: The coronavirus disease 2019 (COVID-19) pandemic has caused unprecedented stress. Mindfulness-based interventions (MBIs) are known to be effective in reducing stress. However, it is unclear how long-term outcomes differ between those who continue mindfulness practice after MBIs and those who do not. In this study, we hypothesized that those who continued mindfulness practice would have higher stress tolerance, and we examined this hypothesis through a survey of MBI graduates. In this study, we examined the association between the continuation of mindfulness practice among MBI completers and individual stress during the COVID-19 epidemic. Methods: A cross-sectional survey of MBI graduates was conducted. The physical and mental health states were compared between those who established a habit of mindfulness practice (practice group) and those who did not (no practice group). Results: The data were collected from 95 participants (response rate: 53.7%). Of the total respondents, 66 (69.5%) practiced mindfulness. Although the degree of perceived stress due to the COVID-19 pandemic was not statistically different between the practice and no practice groups, the practice group showed significantly lower levels of depression (p = 0.007), higher levels of resilience (p = 0.006), higher levels of overall health (p = 0.006), and higher levels of mental health (p = 0.039). The effect of mindfulness practice on reducing depression was fully mediated by resilience. Conclusion: Among MBI graduates, those who regularly practiced mindfulness had lower levels of depression and higher levels of physical and mental health. Thus, the continuation of mindfulness practice increases resilience, buffers against new stressors such as the COVID-19 pandemic, and has the potential to prevent depression.

A Cross-Sectional Study of the Impact of Pain Severity on Absenteeism and Presenteeism Among Japanese Full-Time Workers.

INTRODUCTION: Pain is known to have a high impact on work performance, but there are several confounding factors, such as stress and mental issues. Little is known about the impact of pain severity on work performance when adjusted for such confounding factors. The aim of this study was to identify the effect of pain severity on absence from work (absenteeism) and reduced performance (presenteeism). METHODS: A cross-sectional study was conducted among full-time workers at an industrial manufacturing company in Japan. Participants were assessed using a self-reported questionnaire, including work performance evaluations, pain characteristics, pain-related fear, psychological distress, stress at the workplace and home, workaholism, and self-awareness. Principal component analysis was utilized to decrease the dimensions of the measures, and orthogonal rotation was performed on identified components with an eigenvalue > 1.0. Multivariable logistic regression analyses were performed to determine the association between pain severity and absenteeism and presenteeism, and were adjusted for confounding factors. We also analyzed the association between pain intensity and presenteeism using multivariable logistic regression analyses. RESULTS: A total of 349 workers participated in the study. Six principal components were identified as confounding factors: work stress, regulation, mental instability, less support, home stress, and life dissatisfaction. Multivariable logistic regression analyses showed significant associations of moderate to severe pain with absenteeism (p = 0.02) and low and high presenteeism (p = 0.004 and 0.009, respectively), adjusted for age, sex, body mass index, short sleep, and the six principal components. Pain intensity was also significantly associated with low and high presenteeism (p = 0.002 and 0.014, respectively) in people with pain. CONCLUSIONS: Pain severity is a risk factor for absenteeism and presenteeism, even if workers have comorbid psychological stress or mental health problems.

Improvement in Disability Mediates the Effect of Self-Efficacy on Pain Relief in Chronic Low Back Pain Patients with Exercise Therapy.

Background: The biopsychosocial mechanism by which exercise leads to improvement in chronic low back pain (CLBP) remains unstudied. This prospective cohort study was performed to examine the effectiveness of exercise on pain, disability, and psychological status for CLBP. We also tested path analytic models in which changes in these variables were included. Methods: CLBP patients who visited the Interdisciplinary Pain Center of Keio University Hospital from July 2018 to April 2020 were included. The propensity score matching was performed between patients who underwent exercise (the exercise group) and those who did not (the control group). At the first visit and at the 3-month follow-up, pain (Numerical Rating Scale (NRS)), disability (Pain Disability Assessment Scale (PDAS)), and psychological status (Pain Self-Efficacy Questionnaire (PSEQ), and Pain Catastrophizing Scale (PCS)) were assessed. Changes in pain and disability at the follow-up were compared between the groups. The relationships between changes in pain, disability, and psychological variables were examined using Pearson's correlation and mediation analysis. Results: A significantly larger decrease in the PDAS was observed in the exercise group (N = 49) than in the control (N = 49) (p < 0.05). Increased PSEQ scores were significantly correlated with decreased NRS scores in both groups. In the exercise group, decreased PDAS fully mediated the relationship between increased PSEQ and decreased NRS (P < 0.05). Conclusion: Exercise improved disability, and the improved disability by exercise mediated the effect of increased self-efficacy on pain relief in CLBP patients.

Sitting for long periods is associated with impaired work performance during the COVID-19 pandemic.

OBJECTIVES: The unprecedented coronavirus disease 2019 (COVID-19) pandemic and the corresponding government state of emergency have dramatically changed our workstyle, particularly through implementing teleworking and social distancing. We investigated the degree to which people's work performance is affected and the association between sedentary behavior under the state of emergency and worsened work performance during the COVID-19 pandemic, as previous studies have suggested that sedentary behavior decreases work performance. METHODS: We used data from the Japan "COVID-19 and Society" Internet Survey (JACSIS) study, a cross-sectional, web-based, self-reported questionnaire survey. The main outcome was change in work performance after the COVID-19 pandemic compared with that before the pandemic. We analyzed the association between the change in work performance and sitting duration under the state of emergency, adjusted for work-related stress, participants' demographics, socio-economic status, health-related characteristics, and personality. RESULTS: The change of work environment from the pandemic decreased work performance in 15% of workers, which was 3.6 times greater than the number of workers reporting increased performance in 14 648 workers (6134 women and 8514 men). Although telework both improved and worsened performance (odds ratio [OR], 95% confidence interval [CI] = 2.0, 1.6-2.5 and 1.7, 1.5-1.9, respectively), sitting for long periods after the state of emergency was significantly associated only with worsened performance (OR, 95% CI = 1.8, 1.5-2.2) in a dose-response manner. CONCLUSION: Sitting duration is likely a risk barometer of worsened work performance under uncertain working situations, such as the COVID-19 pandemic.

Loneliness, social isolation, and pain following the COVID-19 outbreak: data from a nationwide internet survey in Japan.

The aim of cross-sectional study was to investigate the association between loneliness, increased social isolation, and pain following the COVID-19 outbreak. A total of 25,482 participants, aged 15-79 years, were assessed using an internet survey; the University of California, Los Angeles Loneliness Scale (Version 3), Short Form 3-item (UCLA-LS3-SF3) was used to assess loneliness, and a modified item of the UCLA-LS3-SF3 was used to measure the perception of increased social isolation during the pandemic. The outcome measures included the prevalence/incidence of pain (i.e., headache, neck or shoulder pain, upper limb pain, low back pain, and leg pain), pain intensity, and the prevalence of past/present chronic pain. Pain intensity was measured by the pain/discomfort item of the 5-level version of the EuroQol 5 Dimension scale. Odds ratios of pain prevalence/incidence and past/present chronic pain prevalence according to the UCLA-LS3-SF3 scoring groups (tertiles) and the frequency of the perceived increase in social isolation (categories 1-5) were calculated using multinomial logistic regression analysis. The mean pain intensity values among different loneliness and social isolation levels were tested using an analysis of covariance. Increased loneliness and the severity of the perceived social isolation were positively associated with the prevalence/incidence of pain, pain intensity, and the prevalence of past/present chronic pain.

Antenatal pain, intimate partner violence, and maternal bonding disorder: data from the Japan Environment and Children's Study.

ABSTRACT: This prospective study examined (1) whether antenatal pain is associated with postnatal maternal bonding disorder (MBD) through postnatal depression and (2) whether intimate partner violence (IPV) has a moderating effect on the association between antenatal pain and postnatal MBD. We analyzed 77,326 pregnancies of women who completed self-report questionnaires including the SF-8 bodily pain item, the Edinburgh Postnatal Depression Scale, the Mother-to-Infant Bonding Scale, and an assessment of IPV. We conducted a mediation analysis to assess whether postnatal depression mediated the association between antenatal pain and MBD 1 year after delivery. A moderated mediation model was used to examine the conditional effect of IPV during pregnancy on the association between antenatal pain and postnatal MBD, operating through postnatal depression. All analyses were adjusted for demographic factors, socioeconomic factors, perinatal and infant factors, medical history, and psychological status. Of the 77,326 pregnancies, 5420 (7.0%) were characterized by persistent moderate-to-severe pain. The total effect of antenatal pain on MBD was significant (standardized path coefficient = 0.06, 95% confidence interval, 0.05-0.06) and postnatal depression dominantly mediated the association between antenatal pain and postnatal MBD (70.8% mediation). Contrary to our hypothesis, IPV during pregnancy did not moderate the association between antenatal pain and postnatal MBD. However, IPV during pregnancy did have independent negative effects on both postnatal depression and MBD. Our findings suggest that antenatal pain and postnatal depression should be assessed and treated with consideration of the presence of IPV during pregnancy to better monitor and prevent the development of MBD.

Association of work performance and interoceptive awareness of 'body trusting' in an occupational setting: a cross-sectional study.

OBJECTIVES: Work performance has been known to be influenced by both psychological stress (mind) and physical conditions (body). The aim of this study was to investigate the association between work performance and 'body trusting', which is a dimension of interoceptive awareness representing mind-body interactions. METHODS: A cross-sectional study was conducted among a sample of workers in an industrial manufacturing company in Japan. Participants were assessed with a self-reported questionnaire including evaluations of work performance, body trusting, psychological distress, pain persistence, workplace and home stressors, and workaholism. Participants' sociodemographic, health and lifestyle characteristics were collected from their annual health check data. The association between work performance and body trusting was examined using multivariable regression analyses in the overall sample and in a subsample of people with pain. RESULTS: A total of 349 workers participated in the study. A significant association between work performance and body trusting was observed, with higher body trusting representing higher work performance. The association was significant after controlling for psychological distress, workplace and home stress, workaholism and participants' characteristics (p<0.001). Compared with people without pain (n=126, 36.1%), people with pain (n=223, 63.9%) showed less body trusting, which was associated with decreased work performance after controlling for pain-related variables (p<0.001). CONCLUSIONS: Workers with higher body trusting showed higher work performance, even after controlling for various influencing factors. Body trusting may be an important target to promote work performance and to prevent loss of performance induced by health problems.