BACKGROUND

Manual cigarette lighter refilling with butane/propane admixed liquefied petroleum gas (LPG) is a common low-income occupation in India. This practice may cause adverse health effects from LPG exposure among such workers.

OBJECTIVE

To assess respiratory status among LPG-exposed workers and non-exposed controls.

METHODS

We quantified the exposure and evaluated respiratory symptoms and lung function among 113 LPG refilling workers (aged 41.9±9.9 years) and 79 controls (aged 40.8±7.2 years). We used multiple linear regression analysis to estimate the LPG exposure response within the group of refilling workers, adjusting for age, height and smoking status.

RESULTS

Compared to the controls, the LPG-exposed lighter refillers manifested a 190 ml decrement in 1-second forced expiratory volume (FEV1) (2.55±0.4 vs. 2.26±0.3 l) and a 6% decrement in FEV1/forced vital capacity (FVC) (both P < 0.05). We found a significantly negative exposure response among the LPG workers: for FVC and FEV1, 44 ml per ml of reported daily LPG use in refilling (P < 0.05).

CONCLUSION

Likely heavy exposure to LPG through manually refilling cigarette lighters is associated with airflow decrements. This adverse effect may be relevant to other occupational groups heavily exposed to volatile hydrocarbons, especially those in marginal employment sectors.

BACKGROUND

Attacks of neuropathic pain, usually abdominal, are characteristic of the acute porphyrias and accompanied by overproduction of heme-precursor molecules, specifically delta-aminolevulinic acid and porphobilinogen. The basis for the acute symptoms in these diseases has been speculative.

METHODS

We review genetic acute porphyria, hereditary tyrosinemia, and an acquired condition, lead poisoning. All perturb heme synthesis and present with a similar pain syndrome.

RESULTS

Although each of these conditions has characteristic urine biochemistry, all exhibit excess delta-aminolevulinic acid. Moreover, in all, treatment with hemin reduces delta-aminolevulinic acid and relieves symptoms. In contrast, use of recombinant porphobilinogen deaminase to knock down porphobilinogen in acute porphyria was ineffective.

CONCLUSIONS

There is now convincing evidence that delta-aminolevulinic acid is the cause of pain in the acute porphyrias. The efficacy of hemin infusion is due mainly, if not entirely, to its inhibition of hepatic delta-aminolevulinic acid synthase-1, the enzyme that catalyzes delta-aminolevulinic acid formation. Delta-aminolevulinic acid synthase-1 is a rational target for additional therapies to control symptoms in acute porphyria.

PURPOSE

Health-related quality of life (HRQL) domains vary across disease conditions and are determined by standards, values, and priorities internal to patients. Although the clinical goals of lung transplantation are to improve patient survival and HRQL, what defines HRQL in lung transplantation is unknown. Employing a qualitative approach, we aimed to identify HRQL domains important in lung transplantation.

METHODS

We conducted semi-structured interviews in purposefully sampled lung transplant recipients (n = 8) representing a spectrum of ages, gender, indications for transplantation, and time since transplantation as well as healthcare practitioners representing a spectrum of practitioner types (n = 9). Grounded theory was used to identify HRQL domains important in lung transplantation, building on but going beyond domains already defined in the SF-36, the most commonly used instrument in this population.

RESULTS

In addition to confirming the relevance of the eight SF-36 domains, we identified 11 novel HRQL domains. Palliation of respiratory symptoms was identified as important. After transplant surgery, new HRQL domains emerged including: distressing symptoms spanning multiple organ systems, worry about infection and acute rejection, treatment burden, and depression. Further, patients identified challenges to intimacy, changes in social relationships, and problems with cognitive functioning. Saliently, worry about limited life expectancy was pervasive and impaired life planning.

CONCLUSIONS

We found that HRQL in lung transplantation is defined by both generic and transplant-specific domains. Delineating and refining these domains can inform efforts to improve clinical outcomes and HRQL measurement in lung transplantation.

PURPOSE

Chronic obstructive pulmonary disease (COPD) is associated with substantial morbidity, including impaired health-related quality of life (HRQoL). Despite the prominent role of occupational factors in the aetiology of COPD, the relationship between these exposures and HRQoL has not been well elucidated.

METHODS

A subpopulation from an epidemiological study, designed to assess the workplace contribution to COPD, was administered the EQ5D HRQoL tool. Demographics, an index of economic deprivation, health endpoints including the presence of COPD and lung function were also recorded. Workplace exposures were categorised using both self-reported exposures and also by the use of an established job exposure matrix (JEM).

RESULTS

A total of 623 individuals participated (mean age 67.1 years). One hundred and forty-eight (24%) reported having received a physician diagnosis of COPD, 355 (57%) were male, and 386 (62%) were ever smokers. As anticipated, the presence of COPD was associated with a poorer HRQoL. Additionally, however, HRQoL was significantly lower in the presence of both self-reported vapours, gases, dusts and fumes exposure and JEM-based exposure irrespective of the presence of COPD. Regression analysis, adjusting for a variety of covariates including the presence of COPD, confirmed a persisting higher likelihood of occupational exposure categorised by JEM being associated with poorer HRQoL scores (β estimate: -0.069; p < 0.05).

CONCLUSIONS

Our findings suggest that work may have an important link to HRQoL and that this effect can persist even among those who have retired. In those with COPD, HRQoL is worse than among those without this condition, but the work-associated decrement appears to be similar across both groups.

BACKGROUND

Despite the high rate of work-related injuries among hospital nurses, there is limited understanding of factors that serve to motivate or hinder nurses return to work following injury.

OBJECTIVES

Perspectives of nurses with work related injuries, as they relate to obstacles and motivations to return to work, consequences of injury, and influences of work climate were documented.

METHODS

This was a sub-study of nurses taken from a larger investigation of hospital workers. A purposive sample of 16 nurses was interviewed. Analysis was carried out using grounded theory as the research method.

RESULTS

Nurses' responses fell into four concepts: organizational influences, personal conditions, costs and losses, and employee health as influenced by workers' compensation systems. Conceptualization of these concepts resulted in key categories: injury as an expected consequence of hospital work; nursing alone versus nursing together; the impact of injury on professional, family, and social roles; and nurses' understanding of and involvement with the workers' compensation system.

DISCUSSION

The findings provide new perspective into features that support or hinder nurses' with injuries return to work and corroborate existing occupational health research. Consideration of these findings by hospital and employee health managers may help promote more effective return to work programs within the hospital setting.

RATIONALE

Links between occupational exposures and morbidity in individuals with established chronic obstructive pulmonary disease (COPD) remain unclear.

OBJECTIVES

To determine the impact of occupational exposures on COPD morbidity.

METHODS

A job exposure matrix (JEM) determined occupational exposure likelihood based on longest job in current/former smokers (n = 1,075) recruited as part of the Subpopulations and Intermediate Outcomes in COPD Study, of whom 721 had established COPD. Bivariate and multivariate linear regression models estimated the association of occupational exposure with COPD, and among those with established disease, the occupational exposure associations with 6-minute-walk distance (6MWD), the Modified Medical Research Council Dyspnea Scale (mMRC), the COPD Assessment Test (CAT), St. George's Respiratory Questionnaire (SGRQ), 12-item Short-Form Physical Component (SF-12), and COPD exacerbations requiring health care utilization, adjusting for demographics, current smoking status, and cumulative pack-years.

MEASUREMENTS AND MAIN RESULTS

An intermediate/high risk of occupational exposure by JEM was found in 38% of participants. In multivariate analysis, those with job exposures had higher odds of COPD (odds ratio, 1.44; 95% confidence interval, 1.04-1.97). Among those with COPD, job exposures were associated with shorter 6MWDs (-26.0 m; P = 0.006); worse scores for mMRC (0.23; P = 0.004), CAT (1.8; P = 0.003), SGRQ (4.5; P = 0.003), and SF-12 Physical (-3.3; P < 0.0001); and greater odds of exacerbation requiring health care utilization (odds ratio, 1.55; P = 0.03).

CONCLUSIONS

Accounting for smoking, occupational exposure was associated with COPD risk and, for those with established disease, shorter walk distance, greater breathlessness, worse quality of life, and increased exacerbation risk. Clinicians should obtain occupational histories from patients with COPD because work-related exposures may influence disease burden.

OBJECTIVE

We aimed to ascertain risk factors for acute mountain sickness (AMS) in miners exposed to chronic intermittent high altitude conditions.

METHODS

All new hires (2009-2012) for mine employment (4000 m above sea level) were followed up for 12 months after first ascent. Demographics, physiologic data, and cigarette smoking were assessed at preemployment screening. Mine site clinic care for AMS defined incident events. Cox regression analysis estimated risk of AMS associated with smoking and selected covariates.

RESULTS

There were 46 AMS cases among 569 individuals during the first 12 months of employment. Adjusted for age, sex, and altitude of permanent residence, cigarettes smoked per day before hiring were prospectively associated with AMS (hazard ratio [HR], 1.9; 95% CI, 1.1 to 3.2 per 10 cigarettes smoked). This risk was higher in the subset of workers with less demanding physical work (n=336; HR, 3.3; 95% CI, 1.7 to 6.3), whereas among those with more physically demanding jobs (n=233), smoking was not associated with increased risk (HR, 0.6; 95% CI, 0.1 to 2.3).

CONCLUSIONS

In workers newly hired to work at high altitude, smoking increases the likelihood of AMS, but this effect appears to be operative only among those with less physically demanding work duties.

PURPOSE

Accumulating evidence suggests an important role for psychosocial work factors in injury, but little is known about the interaction between psychosocial factors and previous injury experience on subsequent injury risk. We examined the relationships between psychosocial work factors and new or recurrent injury among hospital workers.

METHODS

We studied 492 hospital workers including 116 cases with baseline injury and 376 injury-free referents at baseline over follow-up. Job strain, total support, effort-reward imbalance, overcommitment, and musculoskeletal injury at baseline were examined in logistic regression models as predictors of new or recurrent injury experienced during a 2-year follow-up period.

RESULTS

The overall cumulative incidence of injury over follow-up was 35.6 % (51.7 % for re-injury among baseline injury cases; 30.6 % for new injury among referents). Significantly increased risks with baseline job strain (OR 1.26; 95 % CI 1.02-1.55) and effort-reward imbalance (OR 1.42; 95 % CI 1.12-1.81) were observed for injury only among the referents. Overcommitment was associated with increased risk of injury only among the cases (OR 1.58; 95 % CI 1.05-2.39).

CONCLUSIONS

The effects of psychosocial work factors on new or recurrent injury risk appear to differ by previous injury experience, suggesting the need for differing preventive strategies in hospital workers.

BACKGROUND

The association between occupational exposure and autoimmune disease is well recognized for silica, and suspected for other inhalants. We used a large cohort to estimate the risks of rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and dermatomyositis associated with silica and other occupational exposures.

METHODS

We analyzed data for male Swedish construction industry employees. Exposure was defined by a job-exposure matrix for silica and for other inorganic dusts; those with other job-exposure matrix exposures but not to either of the 2 inorganic dust categories were excluded. National hospital treatment data were linked for International Classification of Diseases, 10(th) Revision-coded diagnoses of rheumatoid arthritis (seronegative and positive), systemic lupus erythematosus, systemic sclerosis, and dermatomyositis. The 2 occupational exposures were tested as independent predictors of prospective hospital-based treatment for these diagnoses using age-adjusted Poisson multivariable regression analyses to calculate relative risk (RR).

RESULTS

We analyzed hospital-based treatment data (1997 through 2010) for 240,983 men aged 30 to 84 years. There were 713 incident cases of rheumatoid arthritis (467 seropositive, 195 seronegative, 51 not classified) and 128 cases combined for systemic lupus erythematosus, systemic sclerosis, and dermatomyositis. Adjusted for smoking and age, the 2 occupational exposures (silica and other inorganic dusts) were each associated with increased risk of rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and dermatomyositis combined: RR 1.39 (95% confidence interval [CI], 1.17-1.64) and RR 1.31 (95% CI, 1.11-1.53), respectively. Among ever smokers, both silica and other inorganic dust exposure were associated with increased risk of rheumatoid arthritis (RRs 1.36; 95% CI, 1.11-1.68 and 1.42; 95% CI, 1.17-1.73, respectively), while among never smokers, neither exposure was associated with statistically significant increased risk of rheumatoid arthritis.

CONCLUSION

This analysis reaffirms the link between occupational silica and a range of autoimmune diseases, while also suggesting that other inorganic dusts may also impart excess risk of such disease.

BACKGROUND

There is a well-established association between inhalational exposure to silica and autoimmune disease. We recently observed an outbreak of silica-related autoimmune disease among synthetic stone construction workers with silicosis referred for lung transplantation assessment.

AIMS

To characterize the rheumatologic complications in silicosis within these highly exposed, clinically well-characterized patients.

METHODS

We systematically reviewed data from all cases of silicosis due to synthetic stone dust referred to our pulmonary institute for lung transplant assessment, which represents the national centre for all such referrals. In addition to silicosis-specific data, we extracted data relevant to the clinical and serological manifestations of autoimmune diseases present in these patients.

RESULTS

Of 40 patients in our advanced silicosis national data, we identified nine (23%) with findings consistent with various autoimmune diseases. Among these nine, three also had findings consistent with pulmonary alveolar proteinosis. Based on an expected autoimmune disease prevalence of 3% (based on the upper-end estimate for this group of diseases in European international data), the proportion of disease in our group represents a >7-fold excess (prevalence ratio 7.5; 99% confidence interval 2.6-16.7).

CONCLUSIONS

These cases underscore the strong link between silicosis and multiple distinct syndromes of autoimmune diseases. Vigilance is warranted for the recognition of autoimmune complications in persons with known silicosis; so too is consideration of the occupational exposure history in persons presenting with manifestations of autoimmune disease.