Evaluation of hand-arm vibration syndrome owing to nerve conduction study and cumulative exposure index -A 2.5-year cohort study.

OBJECTIVE: This study aims to clarify the relationship between peripheral neuropathy in hand-arm vibration syndrome and cumulative exposure index. METHODS: 68 participants without symptoms were surveyed. The participants were divided into three groups based on past and current vibration exposure (VE). RESULTS: Comparison among groups according to past VE showed that the median and ulnar sensory nerve conduction velocities and median sensory nerve action potential (SNAP) amplitude were significantly lower in past high and low exposure groups than in the past non-exposure group. Comparison among groups according to current VE showed that the median and ulnar SNAP amplitudes were significantly lower in the current high exposure group than in the current low or non-exposure group. CONCLUSIONS: Vibration tool handlers have potential peripheral nerve lesions at a certain stage without subjective symptoms of the finger.

[Evaluation of self-administered questionnaire items used in regular health check-ups at the workplace by occupational health professionals].

OBJECTIVE: Currently, there is no standardized questionnaire for regular workplace health check-ups in Japan. We considered that there are several issues associated with this, including the possibility that the questionnaire items are not useful for occupational health staff. Therefore, our study aimed to examine the questionnaire items required in regular health check-ups from the occupational health practice perspective and prepare a draft of a standardized medical questionnaire. The ultimate goal is to promote integrated management and utilization of the health-related information obtained from the questionnaire in the future. METHODS: This non-interventional study, conducted from February 2018 to November 2020, examined the questionnaire items for the regular health check-up using the Delphi method. Twenty-two occupational health professionals, including occupational physicians and nurses with qualifications in occupational health, participated in the study. The self-administered questionnaires used by contracted industrial health associations across Japan were obtained, and items from all questionnaires were extracted. A survey questionnaire was then developed, consisting of eight primary headings: "personal attributes," "work-related information and work history," "life history and subjective symptoms," "current and past medical history," "family history," and "pregnancy status," with a total of 589 items. Participants were asked to rate the degree of necessity for each item, excluding the items in "personal attributes" and "pregnancy status." The items with low ratings were excluded, and the remaining items were redesigned and distributed to the participants with the tabulated results. This process was repeated three times to allow the participants to rate the necessity of the items consistently. The questionnaire items with a consensus ratio exceeding 70% on the third try were adopted. The final adopted questionnaire items were again reviewed by the participants and agreed upon by all. RESULTS: A total of 85 items were adopted under five primary headings, including 12 items for "work-related information and work history," 11 for "life history," 22 for "subjective symptoms," 37 for "current medical history," and three for "past medical history." CONCLUSION: The items for the regular health check-up were finally adopted under the primary headings of "work-related information and work history," "subjective symptoms," and "current medical history." We assumed that these items provide an overview of health information that can be utilized in occupational health practice. Based on our findings, there is a need to develop a standardized questionnaire for regular health check-ups and to consider the management and utilization of workers' health information.

Intraoperative Remifentanil Dosage in Surgery for Adolescent Idiopathic Scoliosis Does Not Increase Postoperative Opioid Consumption When Combined With Epidural Analgesia: A Retrospective Cohort Study.

Background In adults, high-dose remifentanil during surgery has been reported to increase postoperative opioid consumption, but this has not been well documented in children. Multimodal analgesia is recommended in the perioperative period for adolescent idiopathic scoliosis (AIS), but no report has examined opioid consumption under epidural analgesia, which is one of the most common types of analgesia. Aims To investigate the association between intraoperative remifentanil dosage and postoperative opioid consumption in AIS in the setting of combined epidural analgesia for postoperative multimodal analgesia. Methods In this retrospective cohort study, patients aged 10-18 years who underwent surgery for scoliosis and epidural analgesia for postoperative pain between July 2012 and April 2019 were included. The primary endpoint was the association between intraoperative cumulative weight-adjusted remifentanil dosage and logarithmic transformation of cumulative weight-adjusted fentanyl consumption in the intensive care unit (ICU). Nonopioid analgesics were investigated as secondary endpoints. An epidural catheter was inserted by the surgeon intraoperatively, and a local anesthetic was administered at the end of the surgery. Multivariate linear regression analysis with adjustment for confounders was performed for all analyses. Results In total, 142 patients were included, and the median intraoperative remifentanil dosage for all patients was 0.27 (interquartile range, 0.24-0.34) µg/kg/min. No association was observed between cumulative weight-adjusted intraoperative dosage of remifentanil and fentanyl, even after adjusting for potential confounders (slope = -1.25; 95% confidence interval [CI], -4.35 to 1.85; P = 0.43). No association was observed between nonopioid analgesic use and intraoperative remifentanil dosage. Conclusion No association was noted between remifentanil dosage during surgery for AIS and postoperative opioid consumption with epidural analgesia. However, this study has limitations due to its retrospective design; thus, further prospective studies are warranted.

The Relationship Between Fear-avoidance Beliefs in Employees with Chronic Musculoskeletal Pain and Work Productivity: A Longitudinal Study.

This study aimed to identify risk factors for chronic musculoskeletal pain (CMSP) and sought to examine the effect of fear-avoidance beliefs (FABs) on work productivity in workers with CMSP. We performed a longitudinal study using self-administered questionnaires given to employees in three different industries between April 2016 and March 2017. The questionnaire concerned background characteristics, work-related factors and musculoskeletal pain, the Work Functioning Impairment Scale (WFun), and the Japanese version of the Tampa Scale for Kinesiophobia (TSK-J). We performed logistic regression analysis to evaluate factors affecting CMSP and a multi-way analysis of variance to analyze the relationship between FABs and CMSP and the effect of FABs on the ability to function at work. Age (odds ratio [OR] = 1.02, 95% confidence interval [CI]: 1.00-1.03), mean working hours (OR = 1.18, 95% CI: 1.04-1.33), and changes in working hours (OR = 1.18, 95% CI: 1.02-1.37) were significantly associated with CMSP. Regarding FABs, we found that the stronger the FAB, the greater the WFun score, and that an increase in FABs resulted in a significant increase in WFun scores. This study demonstrated that long or increased working hours may be risk factors for CMSP, and that stronger FABs in those with CMSP are associated with decreased ability to function at work. In addition, measures to reduce FABs in workers with CMSP may be effective.

Relationships Between Chronic Musculoskeletal Pain and Working Hours and Sleeping Hours: A Cross-sectional Study.

Ten to twenty percent of the population of Japan has chronic pain. Although studies have confirmed a relationship between sleeping hours and chronic pain, it remains unclear whether there is an association between working hours and chronic pain, especially chronic musculoskeletal pain (CMP), in workers. A self-administered questionnaire that sought information regarding background characteristics and work-related factors was sent to 118 enterprises; finally, 1,747 participants were included in the analysis and were classified into CMP (n = 448) and non-CMP (n = 1299) groups. Logistic regression analysis revealed that age (odds ratio [OR] = 1.02, 95% confidence interval [CI]: 1.01-1.03), sex (reference: female, OR = 0.68, 95% CI: 0.52-0.88), working hours (OR = 1.11, 95% CI: 1.03-1.20), and sleeping hours (OR = 0.84, 95% CI: 0.75-0.95) were significantly associated with CMP. Participants were categorized into four groups according to working hours (long: ≥ 9 hours/day [long-work], short: < 9 hours/day [short-work]) and sleeping hours (long: ≥ 7 hours/day [long-sleep], short: < 7 hours/day [short-sleep]). Furthermore, logistic regression analysis showed that the CMP OR was 2.02 (95% CI: 1.46-2.78) times higher in 'long-work plus short-sleep workers' and 1.47 (95% CI: 0.94-2.30) times higher in 'long-work plus long-sleep workers' than in 'short-work plus long-sleep workers'. Thus, working hours are associated with CMP frequency, but sleeping sufficiently may prevent CMP in workers even if they work for long hours. In conclusion, adequate instructions on sleeping hours should be provided by occupational health staff, as this may be effective in preventing CMP.

Investigation of the working behavior of part-time occupational physicians using practical recording sheets.

OBJECTIVES: We investigated the working behavior of part-time occupational physicians using practical recording sheets to clarify issues of occupational physicians' activities according to industrial groups or size of business. METHODS: We collected 561 recording sheets in 96 industries from 11 part-time occupational physicians as collaborators, who volunteered to be a part of this research. We collected a variety of information from the practical recording sheets, including the industry in which each occupational physician was employed, the annual number of times of work attendance, occupational physician-conducted workplace patrol, and employee health management. We investigated their annual practices regarding work environment management, work management, health management, and general occupational health management. In addition, we analyzed the differences between the secondary and tertiary industry groups and between the group of offices employing 100 people or fewer (≤100 group) and 101 people and above (≥101 group) in each industry group. RESULTS: The median work attendance by all occupational physicians was four times a year; the tertiary industry group had a significantly lower rate of work attendance than the secondary industry group. The occupational physicians' participation in risk assessment, mental health measures or overwork prevention, and the formulation of the occupational health management system and the annual plan were significantly lower in the tertiary industry group than in the secondary industry group. We observed that for the annual number of times of work attendance, occupational physician-conducted workplace patrol was significantly lower in the ≤100 group than in the ≥101 group in each industry group. CONCLUSIONS: These findings show that occupational physicians' activities have not been conducted enough in tertiary industries and small-sized offices employing ≤100 people. It would be necessary to evaluate how to provide occupational health service or appropriate occupational physicians' activities for small-sized offices or tertiary industries. Thereafter, it would likely be beneficial to construct a system to support the activities of part-time occupational physicians as well as the activity of occupational health at workplaces.

C-terminal of human histamine H1 receptors regulates their agonist-induced clathrin-mediated internalization and G-protein signaling.

It has been suggested that the agonist-induced internalization of G-protein-coupled receptors from the cell surface into intracellular compartments regulates cellular responsiveness. We previously reported that Gq/11 -protein-coupled human histamine H1 receptors internalized via clathrin-dependent mechanisms upon stimulation with histamine. However, the molecular determinants of H1 receptors responsible for agonist-induced internalization remain unclear. In this study, we evaluated the roles of the intracellular C-terminal of human histamine H1 receptors tagged with hemagglutinin (HA) at the N-terminal in histamine-induced internalization in Chinese hamster ovary cells. The histamine-induced internalization was evaluated by the receptor binding assay with [3 H]mepyramine and confocal immunofluorescence microscopy with an anti-HA antibody. We found that histamine-induced internalization was inhibited under hypertonic conditions or by pitstop, a clathrin terminal domain inhibitor, but not by filipin or nystatin, disruptors of the caveolar structure and function. The histamine-induced internalization was also inhibited by truncation of a single amino acid, Ser487, located at the end of the intracellular C-terminal of H1 receptors, but not by its mutation to alanine. In contrast, the receptor-G-protein coupling, which was evaluated by histamine-induced accumulation of [3 H]inositol phosphates, was potentiated by truncation of Ser487, but was lost by its mutation to alanine. These results suggest that the intracellular C-terminal of human H1 receptors, which only comprises 17 amino acids (Cys471-Ser487), plays crucial roles in both clathrin-dependent internalization of H1 receptors and G-protein signaling, in which truncation of Ser487 and its mutation to alanine are revealed to result in biased signaling toward activation of G-proteins and clathrin-mediated internalization, respectively.