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Objectives: This study aimed to evaluate the influence of individual characteristics (sex, age, body mass index [BMI] and smoking habits) on the tolerance time, pain ratings and rewarming time of hand cold stress testing (CST).

Methods: We included 153 subjects (63% men) working in a Swedish open-pit mine (participation rate 41%). The right hand was immersed in 3 °C circulating water for up to 45 s. Pain ratings were registered every fifth second using a visual analog scale.

Results: The tolerance time (mean ± standard deviation) was 35 ± 12 s for men and 29 ± 14 s for women (p = 0.007). The youngest age group (18–29 years) had the longest tolerance time, while the oldest group (54–65 years) had the shortest (p = 0.005). Women had significantly higher pain ratings than men after 5, 10 and 25 s. The group with the highest BMI had the shortest rewarming time (p < 0.001).

Conclusions: Age and sex influenced the tolerance time of hand CST, while only sex affected the pain ratings and BMI the rewarming time. When performing CST in future studies, these parameters should be considered.

This article presents a pilot study of a 1-h workplace educational intervention implemented among ten construction workers who were highly exposed to hand–arm vibration. The intervention combined risk communication and normative expert advice intended to reinforce preventive behaviour related to vibration, noise, and biomechanical loads. Data for this study comprised intervention notes and interview data from interventionists, and pre- and post-intervention interview data from participating workers.

The results suggested that the intervention was sensitive to disturbances and should be directed only to motivated workers possessing sufficient self-efficacy, and only in circumstances in which exposure may be controlled on the local workplace level and by locally implemented measures. Unless these conditions are present, the studied intervention may fail to influence preventive behaviour, and may instead cause cognitive dissonance and frustration among participants and interventionists.

Background: Vibration induced white fingers (VWF) is one form of secondary Raynaud's phenomenon (RP).

Methods: Vibration exposed workers with RP and vibration exposed controls without RP participated. Blood samples were collected before and after cold challenge exposure (COP). The concentration of von Willebrand factor (vonWf), thrombomodulin (TM), serotonin (SER), endothelin‐1 (ET1), calcitonin gene‐related peptide, or thromboxane A2 was calculated. The diagnostic usefulness of the substances for ruling in the diagnosis of Raynaud's was evaluated.

Results: The cases showed a significant lower concentration of vonWf before and after COP, a significant increase of ET1 and a decrease of TM after COP. The diagnostic usefulness of vonWf showed a likelihood of defining a true case by 35%.

Conclusions: vonWf, TM, SER, or ET1 are suggested biomarkers for VWF. Diagnostic evaluation of vonWf showed a likelihood of defining a true case by 35% in the diagnosis of RP related to vibration.

Background: Raynaud's phenomenon and neurosensory symptoms are common after hand-arm vibration exposure. Knowledge of early signs of vibration injuries is needed. Aims: To investigate the risk of developing Raynaud's phenomenon and paraesthesia in relation to sensation of cold hands in a cohort of male employees at an engineering plant. Methods: We followed a cohort of male manual and office workers at an engineering plant in Sweden for 21 years. At baseline (1987 and 1992) and each follow-up (1992, 1997, 2002, 2008), we assessed sensation of cold, Raynaud's phenomenon and paraesthesia in the hands using questionnaires and measured vibration exposure. We calculated risk estimates with univariate and multiple logistic regression analyses and adjusted for vibration exposure and tobacco usage. Results: There were 241 study participants. During the study period, 21 individuals developed Raynaud's phenomenon and 43 developed paraesthesia. When adjusting the risk of developing Raynaud's phenomenon for vibration exposure and tobacco use, the odds ratios were between 6.0 and 6.3 (95% CI 2.2-17.0). We observed no increased risk for paraesthesia in relation to a sensation of cold hands. Conclusions: A sensation of cold hands was a risk factor for Raynaud's phenomenon. At the individual level, reporting a sensation of cold hands did not appear to be useful information to predict future development of Raynaud's phenomenon given a weak to moderate predictive value. For paraesthesia, the sensation of cold was not a risk factor and there was no predictive value at the individual level.

Objective: The aim was to examine if exposure to whole-body vibration (WBV) increases the risk for hospitalization due to lumbar disc herniation.

Methods: The study basis is a cohort of 288,926 Swedish construction workers who participated in a national occupational health surveillance programme from 1971 until 1992. Job title, smoking habits, body weight, height and age were registered at the examinations. Assessment of WBV were made for each of the constituent occupations by constructing a job-exposure matrix (JEM). Exposure to WBV was graded on a scale from 0 to 5. In addition, the occurrence of hospitalization due to lumbar disc herniation from January 1st 1987 until December 31st 2010 was collected from a linkage with the Swedish Hospital Discharge Register. Poisson regressions were used to estimate relative risk with 95 percent confidence intervals (95% CI), adjusting for age, height, weight and smoking, using white-collar workers and foremen as a reference group.

Results: There was an increased risk for hospitalization due to lumbar disc herniation for workers in the construction industry exposed to medium to high WBV compared to white-collar workers and foremen 1.35 (1.12-1.63). When restricting the analyses to include workers 30-49 years of age at the time of the hospital admission the risk was 1.69 (95% CI 1.29-2.21).

Conclusion: This study further supports that occupational exposure to whole-body vibration increases the risk for hospitalization due to lumbar disc herniation.

Purpose: To study the association of self-reported pain in adolescence with low back pain (LBP) in adulthood among mine workers and, also, study associations between the presence of LBP over 12-month or one-month LBP intensity during a health examination and daily ratings of LBP three and nine months later. Methods: Mixed design with data collected retrospectively, cross-sectionally, and prospectively. Data was collected using a questionnaire during a health examination and by using self-reported daily ratings of LBP three and nine months after the examination. Results: Pain prevalence during teenage years was 55% and it was 59% at age 20. Pain during teenage years had a relative risk of 1.33 (95% confidence interval 1.03-1.73) of LBP 12 months prior to the health examination, but with no associations with LBP intensity or LBP assessed by text messaging. Pain at age 20 years was not associated with any measure of LBP in adulthood. Daily ratings of LBP were associated with LBP during the health examination three and nine months earlier. Conclusions: There were no clear associations between self-reported pain in adolescence and LBP in adulthood. Self-reported daily ratings of LBP were associated with LBP from the health examination. Possible limitations for this study were the retrospective design and few participants.

Background

Increased occurrence of Raynaud's phenomenon, neurosensory injury and carpal tunnel syndrome has been reported for more than 100 years in association with work with vibrating machines. The current risk prediction modelling (ISO-5349) for "Raynaud's phenomenon" is based on a few studies published 70 to 40 years ago. There are no corresponding risk prediction models for neurosensory injury or carpal tunnel syndrome, nor any systematic reviews comprising a statistical synthesis (meta-analysis) of the evidence.

Objectives

Our aim was to provide a systematic review of the literature on the association between Raynaud's phenomenon, neurosensory injuries and carpal tunnel syndrome and hand-arm vibration (HAV) exposure. Moreover the aim was to estimate the magnitude of such an association using meta-analysis.

Methods

This systematic review covers the scientific literature up to January 2016. The databases used for the literature search were PubMed and Science Direct. We found a total of 4,335 abstracts, which were read and whose validity was assessed according to pre-established criteria. 294 articles were examined in their entirety to determine whether each article met the inclusion criteria. The possible risk of bias was assessed for each article. 52 articles finally met the pre-established criteria for inclusion in the systematic review.

Results

The results show that workers who are exposed to HAV have an increased risk of vascular and neurological diseases compared to non-vibration exposed groups. The crude estimate of the risk increase is approximately 4-5 fold. The estimated effect size (odds ratio) is 6.9 for the studies of Raynaud's phenomenon when including only the studies judged to have a low risk of bias. The corresponding risk of neurosensory injury is 7.4 and the equivalent of carpal tunnel syndrome is 2.9.

Conclusion

At equal exposures, neurosensory injury occurs with a 3-time factor shorter latency than Raynaud's phenomenon. Which is why preventive measures should address this vibration health hazard with greater attention.

Objectives: This cross-sectional questionnaire study was carried out at 4 open-pit mines in Finland, Norway, Russia and Sweden as part of the MineHealth project. The aim has been to compare the prevalence of musculoskeletal symptoms between drivers of mining vehicles and non-drivers. Material and Methods: The mine workers were asked whether they had suffered from any musculoskeletal symptoms during the previous 12 months in specified body regions, and to grade the severity of these symptoms during the past month. They were also asked about their daily driving of mining vehicles. Results: The questionnaire was completed by 1323 workers (757 vehicle drivers) and the reported prevalence and severity of symptoms were highest for the lower back, followed by pain in the neck, shoulder and upper back. Drivers in the Nordic mines reported fewer symptoms than non-drivers, while for Russian mine workers the results were the opposite of that. The daily driving of mining vehicles had no significant association with the risk of symptoms. Female drivers indicated a higher prevalence of symptoms as compared to male drivers. Conclusions: The study provided only weak support for the hypothesis that drivers of vehicles reported a higher prevalence of musculoskeletal symptoms than non-vehicle drivers. There were marked differences in the prevalence of symptoms among workers in various enterprises, even though the nature of the job tasks was similar.

PURPOSE: To describe the self-reported ambient cold exposure in northern Sweden and to relate the level of cumulative cold exposure to the occurrence of sensory and vascular hand symptoms. We hypothesize that cold exposure is positively related to reporting such symptoms.

METHODS: A questionnaire about cold exposure and related symptoms was sent out to 35,144 subjects aged 18-70 years and living in northern Sweden.

RESULTS: A total of 12,627 out of 35,144 subjects returned the questionnaire (response rate 35.9%). Subjects living in the rural alpine areas reported more extensive cold exposure both during work and leisure time compared to the urbanized coastal regions. Frostbite in the hands was present in 11.4% of men and 7.1% of women, cold sensitivity was present in 9.7 and 14.4%, and Raynaud's phenomenon was present in 11.0% of men and 14.0% of women. There was a positive association between cumulative cold exposure and neurovascular hand symptoms.

CONCLUSION: The present study demonstrates that the cold environment in northern Sweden might be an underestimated health risk. Our hypothesis that cold exposure is positively related to reporting of neurovascular hand symptoms was supported by our findings. In addition, such symptoms were common not only in conjunction with an overt cold injury. Our results warrant further study on pathophysiological mechanisms and suggest the need for confirmatory prevalence studies to support national public health planning.

PURPOSE: To investigate whether exposure to cold could influence the thermal perception thresholds in a working population.

METHODS: This cross-sectional study was comprised of 251 males and females and was carried out at two mines in the northern part of Norway and Sweden. The testing included a baseline questionnaire, a clinical examination and measurements of thermal perception thresholds, on both hands, the index (Digit 2) and little (Digit 5) fingers, for heat and cold.

RESULTS: The thermal perception thresholds were affected by age, gender and test site. The thresholds were impaired by experiences of frostbite in the fingers and the use of medication that potentially could affect neurosensory functions. No differences were found between the calculated normative values for these workers and those in other comparative investigations conducted in warmer climates.

CONCLUSIONS: The study provided no support for the hypothesis that living and working in cold climate will lead to impaired thermal perception thresholds. Exposure to cold that had caused localized damage in the form of frostbite was shown to lead to impaired thermal perception.