Reducing occupational stress with a B-vitamin focussed intervention: a randomized clinical trial: study protocol.

BACKGROUND: Workplace stress in Australia and other western countries has been steadily increasing over the past decade. It can be observed not only in terms of increased compensation claims but also costs due to absenteeism, loss of productivity at work and reduced psychological and physiological health and well-being. Given the cost and pervasive effects of stress in the modern workforce, time efficient and cost-effective interventions capable of reducing occupational stress (or strain) and burnout are urgently required for the improved well-being of stressed employees. One intervention gaining scientific traction is supplementation with nutritional interventions, particularly the B group vitamins. METHODS: This study was developed to examine the effects of B group vitamins on workplace stress and mood variables with a sample of full-time employed older adults who subjectively report feeling stressed. The study is a randomized, double-blind, placebo-controlled, parallel-groups clinical trial where 200 (N = 100/group) participants will be randomized to receive Blackmores® Executive B Stress Formula or placebo daily for a period of 6 months. Participants will be tested at baseline and 6 months post-randomization on workplace stress, cognitive, personality and mood measures, cardiovascular (brachial and aortic systolic and diastolic blood pressures as well as arterial stiffness), biochemical (assays to measure inflammation and safety) as well as genetic assessments (to assess stress processing) and neuroimaging measures (to investigate in vivo mechanisms of action of B vitamins). In addition to this pre- and post- supplementation testing, participants will also complete a battery of self-report questionnaires online to assess their stress and mood once a month for the duration of the study. The primary aim of the study is to investigate the effects of B vitamin supplementation on work related stress. The secondary aims are to explore the mechanisms underpinning any changes in mood or workplace stress due to the B vitamin intervention by examining relationships between cognitive, biological, neuroimaging and cardiovascular variables over 6 months. A subset of 40 participants (N = 20/group) will undergo neuroimaging at baseline and at 6 months using functional magnetic resonance imaging (fMRI) and magnetic resonance spectroscopy (MRS) in order to further explore in vivo mechanisms of action of B vitamins. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Register (ANZCTR):ACTRN12613000294752.

Chronic obstructive pulmonary disease among residents of an historically industrialised area.

OBJECTIVE: To assess the contribution of workplace exposures to chronic obstructive pulmonary disease (COPD) risk in a community with a heavy burden of past industrial employment. METHODS: A random population sample of Sheffield, U.K. residents aged over 55 years (n=4000), enriched with a hospital-based supplemental sample (n=209), was approached for study. A comprehensive self-completed questionnaire elicited physician-made diagnoses, current symptoms, and past workplace exposures. The latter were defined in three ways: self-reported exposure to vapours, gases, dusts and fumes (VGDF); response to a specific exposure checklist; and through a job exposure matrix (JEM) assigning exposure risk likelihood based on job history independent of respondent-reported exposure. A subset of the study group underwent lung function testing. Population attributable risk fractions (PAR%), adjusted for age, sex and smoking, were calculated for association between workplace exposure and COPD. RESULTS: 2001 (50%) questionnaires were returned from the general population sample and 60 (29%) by the hospital supplement. Among 1754 with complete occupational data, any past occupational exposure to VGDF carried an adjusted excess risk for report of a physician's diagnosis of COPD, emphysema, or chronic bronchitis (ORs 3.9; 95% CI 2.7 to 5.8), with a corresponding PAR% value of 58.7% (95% CI 45.6% to 68.7%). The PAR% estimate based on JEM exposure was 31%. From within the subgroup of 571 that underwent lung function testing, VGDF exposure was associated with a PAR% of 20.0% (95% CI -7.2 to 40.3%) for Global initiative for chronic obstructive lung disease (GOLD) 1 (or greater) level of COPD. CONCLUSION: This heavy industrial community-based population study has confirmed significant associations between reported COPD and both generic VGDF and JEM-defined exposures. This study supports the predominantly international evidence-based notion that workplace conditions are important when considering the current and future respiratory health of the workforce.