Description: Objectives Healthcare workers have high rates of low back pain (LBP) related to handling patients. A large chain of nursing homes experienced reduced biomechanical load, compensation claims and costs following implementation of a safe resident handling programme (SRHP). The aim of this study was to examine whether LBP similarly declined and whether it was associated with relevant self-reported occupational exposures or personal health factors. Methods Worker surveys were conducted on multiple occasions beginning with the week of first SRHP introduction (baseline). In each survey, the outcome was LBP during the prior 3 months with at least mild severity during the past week. Robust Poisson multivariable regression models were constructed to examine correlates of LBP cross-sectionally at 2 years (F3) and longitudinally at 5–6 years (F5) post-SRHP implementation among workers also in at least one prior survey. Results LBP prevalence declined minimally between baseline and F3. The prevalence was 37% at F3 and cumulative incidence to F5 was 22%. LBP prevalence at F3 was positively associated with combined physical exposures, psychological job demands and prior back injury, while frequent lift device usage and ‘intense’ aerobic exercise frequency were protective. At F5, the multivariable model included frequent lift usage at F3 (relative risk (RR) 0.39 (0.18 to 0.84)) and F5 work–family imbalance (RR=1.82 (1.12 to 2.98)). Conclusions In this observational study, resident lifting device usage predicted reduced LBP in nursing home workers. Other physical and psychosocial demands of nursing home work also contributed, while frequent intense aerobic exercise appeared to reduce LBP risk.

Description: Objective Among the aetiological factors of chronic low back pain (CLBP), occupational factors are often suspected, but their contribution remains to be ascertained. This study aimed to determine the impact of a wide range of occupational factors on the incidence and persistence of CLBP. Method From the VISAT (VIeillissement SAnté Travail) study, 1560 workers were examined at baseline and 5 years later. CLBP was defined as having low back pain or specific treatment for at least 6 months. Participants newly affected with CLBP and those with persistent CLBP at follow-up were distinguished. In addition to individual factors, a broad panel of occupational factors were analysed, covering employment, physical, organisational and psychosocial factors. Multivariate analyses were used to determine predictive factors of incidence and persistence of CLBP. Receiver operating characteristic (ROC) curves were performed to analyse the contribution of occupational factors. Results 22.6% of participants without any CLBP initially presented with CLBP 5 years later, while 53.7% of participants with CLBP at baseline had CLBP at the second collection. Carrying heavy loads, the lack of recognition of completed work and productivity-related income predicted a higher risk of incidence of CLBP. However, no significant association between occupational factors and the risk for persistence of CLBP was observed, while the risk was multiplied by two for history of depression and rheumatological events. ROC curves confirmed the significant contribution of occupational factors to incidence of CLBP. Conclusions Occupational factors played a pivotal role in the incidence of CLBP, while individual factors were the main determinants of persistence of CLBP.

Description: Objectives To examine the longitudinal relationship between incidence of diagnosed chronic disease and work status and hours worked. Methods A dynamic cohort approach was taken to construct our study sample using the Canadian National Population Health Survey. Participant inclusion criteria included being employed and without a chronic health condition in the survey cycle prior to diagnosis, and participation in consecutive surveys following diagnosis. Each respondent was matched with up to 5 respondents without a diagnosed health condition. The direct and indirect associations between chronic disease and work status and hours worked following diagnosis were examined using probit and linear regression path models. Separate models were developed for arthritis, back problems, diabetes, hypertension and heart disease. Results We identified 799 observations with a diagnosis of arthritis, 858 with back pain, 178 with diabetes, 569 with hypertension and 163 with heart disease, which met our selection criteria. An examination of total effects at time 1 and time 2 showed that, excluding hypertension, chronic disease diagnosis was related to work loss. The time 2 effect of chronic disease diagnosis on work loss was mediated through time 1 work status. With the exception of heart disease, an incident case of chronic disease was not related to changes in work hours among observations with continuous work participation. Conclusions Chronic disease can result in work loss following diagnosis. Research is required to understand how modifying occupational conditions may benefit employment immediately after diagnosis.

Description: Objectives Occupational exposure to disinfectants is associated with work-related asthma, especially in healthcare workers. However, little is known about the specific products involved. To evaluate disinfectant exposures, we designed job-exposure (JEM) and job-task-exposure (JTEM) matrices, which are thought to be less prone to differential misclassification bias than self-reported exposure. We then compared the three assessment methods: self-reported exposure, JEM and JTEM. Methods Disinfectant use was assessed by an occupational questionnaire in 9073 US female registered nurses without asthma, aged 49–68 years, drawn from the Nurses' Health Study II. A JEM was created based on self-reported frequency of use (1–3, 4–7 days/week) of 7 disinfectants and sprays in 8 nursing jobs. We then created a JTEM combining jobs and disinfection tasks to further reduce misclassification. Exposure was evaluated in 3 classes (low, medium, high) using product-specific cut-offs (eg, 〈30%, 30–49.9%, ≥50%, respectively, for alcohol); the cut-offs were defined from the distribution of self-reported exposure per job/task. Results The most frequently reported disinfectants were alcohol (weekly use: 39%), bleach (22%) and sprays (20%). More nurses were classified as highly exposed by JTEM (alcohol 41%, sprays 41%, bleach 34%) than by JEM (21%, 30%, 26%, respectively). Agreement between JEM and JTEM was fair-to-moderate ( 0.3–0.5) for most disinfectants. JEM and JTEM exposure estimates were heterogeneous in most nursing jobs, except in emergency room and education/administration. Conclusions The JTEM may provide more accurate estimates than the JEM, especially for nursing jobs with heterogeneous tasks. Use of the JTEM is likely to reduce exposure misclassification.

Description: Objectives Links between arrhythmias and particulate matter exposures have been found among sensitive populations. We examined the relationship between personal particulate matter ≤2.5 µm aerodynamic diameter (PM 2.5 ) exposures and ectopy in a panel study of healthy welders. Methods Simultaneous ambulatory ECG and personal PM 2.5 exposure monitoring with DustTrak Aerosol Monitor was performed on 72 males during work and non-work periods for 5–90 h (median 40 h). ECGs were summarised hourly for supraventricular ectopy (SVE) and ventricular ectopy (VE). PM 2.5 exposures both work and non-work periods were averaged hourly with lags from 0 to 7 h. Generalised linear mixed-effects models with a random participant intercept were used to examine the relationship between PM 2.5 exposure and the odds of SVE or VE. Sensitivity analyses were performed to assess whether relationships differed by work period and among current smokers. Results Participants had a mean (SD) age of 38 (11) years and were monitored over 2993 person-hours. The number of hourly ectopic events was highly skewed with mean (SD) of 14 (69) VE and 1 (4) SVE. We found marginally significant increases in VE with PM 2.5 exposures in the sixth and seventh hour lags, yet no association with SVE. For every 100 μg/m 3 increase in sixth hour lagged PM 2.5 , the adjusted OR (95% CI) for VE was 1.03 (1.00 to 1.05). Results persisted in work or non-work exposure periods and non-smokers had increased odds of VE associated with PM 2.5 as compared with smokers. Conclusions A small increase in the odds of VE with short-term PM 2.5 exposure was observed among relatively healthy men with environmental and occupational exposures.

Description: Objectives Many hairdressers leave their profession due to health problems, including occupational hand eczema, which has been associated with skin exposure to sensitising hair dye components such as paraphenylenediamine (PPD) and paratoluenediamine (PTD). Since the use of protective gloves is advised but without the short-term effect being known, our main goal was to attribute a significant biomarker reduction to adequate glove use, in a real work situation. Methods 11 hairdressers were studied over 2 weeks. In the first week, they worked as usual and (re)used their gloves. Thereafter, we intervened to improve glove use during the second week. In both weeks, workplace exposure data were collected through observations, and systemic exposure was quantified by biomonitoring of PPD and PTD. The effect of improved glove use and other exposure determinants was studied through mixed models analysis. Results We showed that improved glove use significantly reduced mean PTD concentrations from 24.1 before to 4.2 µg/g creatinine after the intervention (n=11, third day postshift). In addition, mean PTD concentrations increased during the first week (14 times elevated after three consecutive shifts), but not during the second week. For PPD, no effect of improved glove use and no accumulation effect were detected. Conclusions Our study is the first to deliver evidence for a significant reduction in systemic exposure to PTD through improved glove use. Disposable gloves should never be reused. PTD biomonitoring is shown to be a practical tool to quantify recent dermal exposure to oxidative hair dye components.

Description: Objectives To examine the benefit of a psychological Stage of Change (SOC) approach, relative to standard ergonomics advice, for the prevention of work-related musculoskeletal pain and discomfort (MSPD). Methods A cluster randomised trial was conducted in South Australia across a broad range of workplaces. Repeated face-to-face interviews were conducted onsite to assess MSPD, safety climate, job satisfaction and other factors. Changes in MSPD across intervention groups and time were investigated using Generalised Estimating Equation (GEE) methods. Results 25 workgroups (involving 242 workers) were randomly allocated to either a standard intervention or an intervention tailored according to SOC. The prevalence of MSPD increased for both groups, but was only significant for the standard group, in respect of lower back MSPD. Workers receiving tailored interventions were 60% less likely to experience lower back MSPD. After adjusting for age, gender and job satisfaction, it was found that company safety climate and length of employment were significantly correlated to the time-intervention effect. There was no correlation with workload. Conclusions Compared with standard ergonomics advice to management, there was evidence of a benefit of stage-matched intervention for MSPD prevention, particularly for low back pain. Organisational safety climate should be taken into account when planning prevention programmes.

Description: Objectives Nurses are at increased risk of occupational asthma, an observation that may be related to disinfectants exposure. Whether asthma history influences job type or job changes among nurses is unknown. We investigated this issue in a large cohort of nurses. Methods The Nurses’ Health Study II is a prospective study of US female nurses enrolled in 1989 (ages 24–44 years). Job status and asthma were assessed in biennial (1989–2011) and asthma-specific questionnaires (1998, 2003). Associations between asthma history at baseline (diagnosis before 1989, n=5311) and job type at baseline were evaluated by multinomial logistic regression. The relations of asthma history and severity during follow-up to subsequent job changes were evaluated by Cox models. Results The analytic cohort included 98 048 nurses. Compared with nurses in education/administration (likely low disinfectant exposure jobs), women with asthma history at baseline were less often employed in jobs with likely high disinfectant exposure, such as operating rooms (odds ratio 0.73 (95% CI 0.63 to 0.86)) and emergency room/inpatient units (0.89 (0.82 to 0.97)). During a 22-year follow-up, nurses with a baseline history of asthma were more likely to move to jobs with lower exposure to disinfectants (HR 1.13 (1.07 to 1.18)), especially among those with more severe asthma (HR for mild persistent: 1.13; moderate persistent 1.26; severe persistent: 1.50, compared with intermittent asthma, p trend: 0.004). Conclusions Asthma history was associated with baseline job type and subsequent job changes among nurses. This may partly reflect avoidance of tasks involving disinfectant use, and may introduce bias in cross-sectional studies on disinfectant exposure and asthma in nurses.

Description: Introduction Since 2000 a decline in the incidence of occupational asthma (OA) has been reported in the UK and Europe. We aimed to describe and account for trends in the incidence of OA in the West Midlands, UK using annual notification data from the SHIELD voluntary surveillance scheme over the period 1991–2011. Methods All notifications to the SHIELD database between January 1991 and December 2011 were identified, along with patients’ demographic data, occupations, causative agents and confirmatory tests. Annual notifications were scaled to give an annual count per million workers, giving a measure of incidence, and also standardised against those of bakers’ asthma. Non-parametric analyses were undertaken between annual incidence and time (years) for common causative agents using (1) a negative binomial regression univariate model and (2) a logistic regression model calculating annual reporting ORs. A step-change analysis was used to examine time points at which there were marked reductions in incidence. Results A decrease in annual incidence of OA was observed over the study period (incident rate ratio=0.945; 95% CI 0.933 to 0.957; p〈0.0001), an effect that was lost after standardising for bakers’ asthma. Decreases in incidence were seen for most common causative agents, with only cleaning product-related OA increasing over 21 years. Marked fall in incidence was seen in 2004 for isocyanates, and in 1995 for latex. Most notifications came from a regional specialist occupational lung disease unit, with notifications from other sites falling from 16 cases/million workers/annum in 1995 to 0 in 2004. Conclusions Reporter fatigue and increasing under-recognition of OA are both factors which contribute to the apparent fall in incidence of OA in the West Midlands. There is a future need for interventions that enable health professionals to identify potential cases of OA in the workplace and in healthcare settings.

Description: Background A few studies have investigated exposure–response relationships for sensitisation to wheat, work-related symptoms and wheat allergen exposure. IgG4 is suggested to protect against the development of allergic sensitisation. The main aim of this current study was to explore the nature of exposure–response relationships for a range of clinically relevant endpoints among bakery workers, and to investigate the role of IgG4 in these relationships. Methods A cross-sectional study of 517 supermarket bakery workers in 31 bakeries used a questionnaire, serum-specific IgE and IgG4 to wheat, and methacholine challenge testing. Exposure models were developed previously using job, bakery size, tasks and specific ingredients used. These models were used to predict average personal exposure to wheat allergens. Results The exposure–response relationships for average exposure followed a linear relationship for sensitisation, but a bell-shaped curve for allergic symptoms and probable occupational asthma, increasing up to 10–15 µg/m 3 wheat allergen concentration after which they plateau off and decrease at higher exposure concentrations. This relationship was modified by atopic status. IgG4 levels were strongly exposure related: a clear increase in prevalence of higher IgG4 with increase in wheat allergen exposure was observed among those sensitised and non-sensitised to wheat, with IgG4 even more strongly associated with exposure than IgE to wheat. Conclusions The bell-shaped exposure–response relationship in the current study is consistent with the findings of previous studies. IgG4 showed no protective effect for sensitisation, confirming the findings of previous studies, suggesting that the pattern is probably related to a healthy worker effect.