Who is likely to develop persistent low back pain? A longitudinal analysis of prognostic occupational factors

OBJECTIVE: Occupational low back pain (LBP) is considered to be the most expensive form of work disability, with the socioeconomic costs of persistent LBP exceeding the costs of acute and subacute LBP by far. This makes the early identification of patients at risk of developing persistent LBP essential, especially in working populations. The aim of the study was to evaluate both risk factors (for the development of persistent LBP) and protective factors (preventing the development of persistent LBP) in the same cohort. PARTICIPANTS: An inception cohort of 315 patients with acute to subacute or with recurrent LBP was recruited from 14 health practitioners (twelve general practitioners and two physiotherapists) across New Zealand. METHODS: Patients with persistent LBP at six-month follow-up were compared to patients with non-persistent LBP looking at occupational, psychological, biomedical and demographic/lifestyle predictors at baseline using multiple logistic regression analyses. All significant variables from the different domains were combined into a one predictor model. RESULTS: A final two-predictor model with an overall predictive value of 78% included social support at work (OR 0.67; 95%CI 0.45 to 0.99) and somatization (OR 1.08; 95%CI 1.01 to 1.15). CONCLUSIONS: Social support at work should be considered as a resource preventing the development of persistent LBP whereas somatization should be considered as a risk factor for the development of persistent LBP. Further studies are needed to determine if addressing these factors in workplace interventions for patients suffering from acute, subacute or recurrent LBP prevents subsequent development of persistent LBP.

Establishing occupational and environmental health design requirements for Lunar and Mars settlements

In a study of Lunar and Mars settlement concepts, an analysis was made of fundamental design assumptions in five technical areas against a model list of occupational and environmental health concerns. The technical areas included the proposed science projects to be supported, habitat and construction issues, closed ecosystem issues, the "MMM" issues--mining, material-processing, and manufacturing, and the human elements of physiology, behavior and mission approach. Four major lessons were learned. First it is possible to relate public health concerns to complex technological development in a proactive design mode, which has the potential for long-term cost savings. Second, it became very apparent that prior to committing any nation or international group to spending the billions to start and complete a lunar settlement, over the next century, that a significantly different approach must be taken from those previously proposed, to solve the closed ecosystem and "MMM" problems. Third, it also appears that the health concerns and technology issues to be addressed for human exploration into space are fundamentally those to be solved for human habitation of the earth (as a closed ecosystem) in the 21st century. Finally, it is proposed that ecosystem design modeling must develop new tools, based on probabilistic models as a step up from closed circuit models. ^

Exposure to the Asp f 1 allergen in nonindustrial occupational environments

Sick Building Syndrome is a prevalent problem with patient complaints similar to typical allergy symptoms. Unlike most household allergens, the Asp f 1 allergen is conceivably ubiquitous in the work environment. This project examined levels of the Asp f 1 allergen in office and non-industrial occupational environments, and studied the bioaerosol and dust reservoirs of Aspergillus fumigatus responsible for those levels. ^ Culturable bioaerosols of total mesophilic fungi were sampled with Andersen N6 impactors. Aggressive airborne and bulk dust samples were concurrently collected and assayed for Asp f 1. Bulk dusts were selectively cultured for A. fumigatus. Samples were collected during both wet and dry climatological conditions to examine the possibility of Asp f 1 increases due to fungal growth blooms. ^ Only very low levels of Asp f 1 were detected in relatively few samples. Analysis of wet versus dry period samples showed no differences in Asp f 1 levels, although A. fumigatus counts from dusts did fluctuate significantly with exterior moisture events as did indoor prevalence of total colony forming units. These results indicate that even in the presence of elevated fungal concentrations, levels of Asp f 1 are extremely low. These levels do not correlate with climatological moisture events, despite distinct fungal blooms in the days immediately following those events. Non-industrial office buildings devoid of indoor air quality issues did not demonstrate significant levels or occurrence of Asp f 1 contamination in the geographical region of this study. ^

THE DESIGN AND DEVELOPMENT OF A SURVEY INSTRUMENT FOR THE ASSESSMENT OF OCCUPATIONAL STRESS

Using stress and coping as a unifying theoretical concept, a series of five models was developed in order to synthesize the survey questions and to classify information. These models identified the question, listed the research study, described measurements, listed workplace data, and listed industry and national reference data.^ A set of 38 instrument questions was developed within the five coping correlate categories. In addition, a set of 22 stress symptoms was also developed. The study was conducted within two groups, police and professors, on a large university campus. The groups were selected because their occupations were diverse, but they were a part of the same macroenvironment. The premise was that police officers would be more highly stressed than professors.^ Of a total study group of 80, there were 37 respondents. The difference in the mean stress responses was observable between the two groups. Not only were the responses similar within each group, but the stress level of response was also similar within each group. While the response to the survey instrument was good, only 3 respondents answered the stress symptom survey properly. It was determined that none of the 37 respondents believed that they were ill. This perception of being well was also evidenced by the grand mean of the stress scores of 2.76 (3.0 = moderate stress). This also caused fewer independent variables to be entered in the multiple regression model.^ The survey instrument was carefully designed to be universal. Universality is the ability to transcend occupational or regional definitions as applied to stress. It is the ability to measure responses within broad categories such as physiological, emotional, behavioral, social, and cognitive functions without losing the ability to measure the detail within the individual questions, or the relationships between questions and categories.^ Replication is much easier to achieve with standardized categories, questions, and measurement procedures such as those developed for the universal survey instrument. Because the survey instrument is universal it can be used as an analytical device, an assessment device, a basic tool for planning and a follow-up instrument to measure individual response to planned reductions in occupational stress. (Abstract shortened with permission of author.) ^

Projecting a relevant "next": Instruction sequences in driving lessons

Car interaction and the organisation of multi-activity in cars have become a fertile topic of research within CA and EM (Laurier 2005, Haddington & Keisanen 2009). While previous research has focused exclusively on everyday car rides, in this paper we will analyse a specific kind of car interaction, namely driving lessons. In addition to"driving" and"talking", as the two main parallel activities in everyday car rides (Mondada in press), in driving lessons a central activity is"instructing", that we understand to be a collaborative accomplishment (Sanchez Svensson et al. 2009). Drawing on a corpus of 7 video-recorded driving lessons, we will analyse the sequential organisation of"instruction sequences", i.e. of those actions that are initiated by the driving instructor with a turn projecting the next relevant action to be executed by the learner. Learners carry out next actions in two different ways: a) as"single" actions (e.g. using the indicator); b) as a complex series of overlapping or parallel actions. We will show that"single" actions occur as responses to instructions concerning the learner's command of the car, while complex actions occur when the instructors formulate direction indications. The aims of our analyses are twofold. Firstly, we will analyse how instruction sequences are fitted to the emerging contingencies of the car ride (movement in space, changing environment): we will show that a) the turn format of the instruction initiation displays the degree of"urgency" of the requested action; b) learners have the possibility to start the relevant"next" before the instruction initiation comes to completion. Secondly, we will focus on those"seconds" that the driving instructor treats as problematic by initiating a repair sequence (e.g. an improper use of the indicator). Our research contributes to the discussion about the multimodal resources that participants can employ to fulfil a projected action. In addition, it offers insights in a hitherto scarcely investigated topic, namely the organisation of instructions and the ecology of apprenticeship. References HADDINGTON, P. & KEISANEN, T. (2009) Location, mobility and the body as resources in selecting a route. Journal of Pragmatics 41 (10), 1938-1961. LAURIER, Eric (2005): Searching for a parking space. Intellectica 41-42/2-3: 101-116. MONDADA, Lorenza (in press). Talking and driving: multi-activity in the car. Semiotica. SANCHEZ SVENSSON, M. et al. (2009) "Embedding instruction in practice: contingency and collaboration during surgical training", Sociology of Health & Illness, 31/6: 889-906.

Driving and dementia: a clinical decision pathway

OBJECTIVE This study aimed to develop a pathway to bring together current UK legislation, good clinical practice and appropriate management strategies that could be applied across a range of healthcare settings. METHODS The pathway was constructed by a multidisciplinary clinical team based in a busy Memory Assessment Service. A process of successive iteration was used to develop the pathway, with input and refinement provided via survey and small group meetings with individuals from a wide range of regional clinical networks and diverse clinical backgrounds as well as discussion with mobility centres and Forum of Mobility Centres, UK. RESULTS We present a succinct clinical pathway for patients with dementia, which provides a decision-making framework for how health professionals across a range of disciplines deal with patients with dementia who drive. CONCLUSIONS By integrating the latest guidance from diverse roles within older people's health services and key experts in the field, the resulting pathway reflects up-to-date policy and encompasses differing perspectives and good practice. It is potentially a generalisable pathway that can be easily adaptable for use internationally, by replacing UK legislation for local regulations. A limitation of this pathway is that it does not address the concern of mild cognitive impairment and how this condition relates to driving safety. © 2014 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons, Ltd.

Driving ability, mental illness and psychotropic medication in the elderly

Fitness to drive in elderly drivers is most commonly discussed with a focus on cognitive impairment. Therefore, this article is focussing on mental illness and the use of psychotropic drugs in elderly drivers, which can both interfere with fitness to drive. Based on a detailed literature review and on clinical judgement, we propose signposts and "red flags" to judge the individual risks. Health professionals dealing with elderly patients should in particular be aware of the dangers related to cumulative risks and need to inform the patients appropriately. For medico-legal reasons the information provided to patients must be written down in the medical record. Individual counselling is important as fitness to drive is a complex topic.

Manipulations to reduce simulator-related transient adverse health effects during simulated driving

User comfort during simulated driving is of key importance, since reduced comfort can confound the experiment and increase dropout rates. A common comfort-affecting factor is simulator-related transient adverse health effect (SHE). In this study, we propose and evaluate methods to adapt a virtual driving scene to reduce SHEs. In contrast to the manufacturer-provided high-sensory conflict scene (high-SCS), we developed a low-sensory conflict scene (low-SCS). Twenty young, healthy participants drove in both the high-SCS and the low-SCS scene for 10 min on two different days (same time of day, randomized order). Before and after driving, participants rated SHEs by completing the Simulator Sickness Questionnaire (SSQ). During driving, several physiological parameters were recorded. After driving in the high-SCS, the SSQ score increased in average by 129.4 (122.9 %, p = 0.002) compared to an increase of 5.0 (3.4 %, p = 0.878) after driving in the low-SCS. In the low-SCS, skin conductance decreased by 13.8 % (p < 0.01) and saccade amplitudes increased by 16.1 % (p < 0.01). Results show that the investigated methods reduce SHEs in a younger population, and the low-SCS is well accepted by the users. We expect that these measures will improve user comfort.

Occupational exposure to magnetic fields and electric shocks and risk of ALS: The Swiss National Cohort

Amyotrophic lateral sclerosis (ALS) has been associated with exposures in so-called 'electrical occupations'. It is unclear if this possible link may be explained by exposure to extremely low-frequency magnetic fields (ELF-MF) or by electrical shocks. We evaluated ALS mortality in 2000-2008 and exposure to ELF-MF and electrical shocks in the Swiss National Cohort, using job exposure matrices for occupations at censuses 1990 and 2000. We compared 2.2 million workers with high or medium vs. low exposure to ELF-MF and electrical shocks using Cox proportional hazard models. Results showed that mortality from ALS was higher in people who had medium or high ELF-MF exposure in both censuses (HR 1.55 (95% CI 1.11-2.15)), but closer to unity for electrical shocks (HR 1.17 (95% CI 0.83-1.65)). When both exposures were included in the same model, the HR for ELF-MF changed little (HR 1.56), but the HR for electric shocks was attenuated to 0.97. In conclusion, there was an association between exposure to ELF-MF and mortality from ALS among workers with a higher likelihood of long-term exposure.

Determination of Δ9-tetrahydrocannabinolic acid A (Δ9-THCA-A) in whole blood and plasma by LC–MS/MS and application in authentic samples from drivers suspected of driving under the influence of cannabis

Delta-9-tetrahydrocannabinolic acid A (THCA-A) is the biosynthetic precursor of delta-9-tetrahydrocannabinol (THC) in cannabis plants, and has no psychotropic effects. THCA-A can be detected in blood and urine, and several metabolites have been identified. THCA-A was also shown to be incorporated in hair by side stream smoke to a minor extent, but incorporation via blood stream or sweat seems unlikely. The detection of THCA-A in biological fluids may serve as a marker for differentiating between the intake of prescribed THC medication – containing only pure THC – and cannabis products containing THC besides THC-acid A and other cannabinoids. However, the knowledge about its usefulness in forensic cases is very limited. The aim of the present work was the development of a reliable method for THCA-A determination in human blood or plasma using LC–MS/MS and application to cases of driving under the influence of drugs. Fifty eight (58) authentic whole blood and the respective plasma samples were collected from drivers suspected of driving under the influence of cannabis from the region of Bern (Switzerland). Samples were first tested for THC, 11-OH-THC and THC-COOH, and then additionally for THCA-A. For this purpose, the existing LC–MS/MS method was modified and validated, and found to be selective and linear over a range of 1.0 to 200 ng/mL (the correlation coefficients were above 0.9980 in all validation runs). Limit of detection (LOD) and limit of quantification (LOQ) were 0.3 ng/mL and 1.0 ng/mL respectively. Intra- and inter-assay accuracy were equal or better than 90% and intra- and inter-assay precision were equal or better than 11.1%. The mean extraction efficiencies were satisfactory being equal or higher than 85.4%. THCA-A was stable in whole blood samples after 3 freeze/thaw cycles and storage at 4 °C for 7 days. Re-injection (autosampler) stability was also satisfactory. THC was present in all blood samples with levels ranging from 0.7 to 51 ng/mL. THCA-A concentrations ranged from 1.0 to 496 ng/mL in blood samples and from 1.4 to 824 ng/mL in plasma samples. The plasma:blood partition coefficient had a mean value of 1.7 (±0.21, SD). No correlation was found between the degree of intoxication or impairment stated in the police protocols or reports of medical examinations and the detected THCA-A-concentration in blood.

Callings and work engagement: Moderated mediation model of work meaningfulness, occupational identity, and occupational self-efficacy

Scholarly interest in callings is growing, but our understanding of how and when callings relate to career outcomes is incomplete. The present study investigated the possibility that the relationship of calling to work engagement is mediated by work meaningfulness, occupational identity, and occupational self-efficacy – and that this mediation depends on the degree of perceived person-job fit. I examined a highly educated sample of German employees (N=529) in diverse occupations and found support for two of the three hypothesized mediators – work meaningfulness and occupational identity – after controlling for the relation of core self-evaluations to work engagement. Contrary to expectations, the mediated relations of callings to work engagement were not conditional upon the degree of person-job fit. The findings are considered in terms of the pathways through which callings may relate to work engagement and other career development outcomes.