Health Inequalities According to Plant Size—Comparison of Small- and Medium-Sized Enterprises

Self-employed persons in Sweden - mortality differentials by industrial sector and enterprise legal form: a five-year follow-up study

OBJECTIVES

This study investigated mortality differentials between self-employed persons in Sweden, considering industrial sector, enterprise characteristics and socio-demographic factors.

METHODS

Data on 321,274 self-employed persons were obtained from population registers in Sweden. Cox proportional hazards models were used to compare all-cause and cause-specific mortality rate ratios by industrial sector and enterprise legal form, adjusted for confounders.

RESULTS

All-cause mortality was 10-32% higher in self-employed persons in Manufacturing and Mining, Trade and Communication, and Not Specified and Other sectors than in Agriculture, Forestry, and Fishing. Mortality from cardiovascular disease was 23% higher in Trade and Communication, and from neoplasms 17-51% higher in Manufacturing and Mining, Not Specified, and Other. Mortality from suicide was 45-60% lower in Personal and Cultural Services, and in Not Specified. Mortality was 8-16% higher in sole proprietorship than limited partnership.

CONCLUSIONS

Further research of working conditions is warranted, considering industry and enterprise legal form.

Systematic review of respiratory case definitions in metalworking fluid outbreaks

BACKGROUND

Since the mid-1990s, outbreaks of asthma and extrinsic allergic alveolitis (EAA) have been identified in workers exposed to metalworking fluids (MWFs). The cause of these outbreaks remains to be determined.

AIMS

To identify and review all previously published occupational lung disease case definitions and diagnostic criteria that have been utilized during MWF outbreak investigations.

METHODS

Respiratory outbreaks due to MWFs were identified by a systematic literature search for articles published between 1990 and October 2011. Investigations reporting the usage of disease case definitions or diagnostic criteria for respiratory disease were reviewed and summarized.

RESULTS

The literature search identified 35 papers relating to 27 outbreaks of respiratory disease in MWF-exposed workers. Fourteen case definitions for MWF-related respiratory disease were identified: seven for EAA, five for occupational asthma and one each for humidifier fever and industrial bronchitis. A single paper was identified where any comparison of different disease case definitions (for EAA) had been performed.

CONCLUSIONS

A range of case definitions and diagnostic criteria for MWF respiratory disease have been utilized in outbreak investigations, but the majority have been produced for individual outbreak investigations without previous validation. It may be difficult to compare the findings of future workplace studies without a more standardized approach to case identification and diagnosis.

Systematic review of respiratory outbreaks associated with exposure to water-based metalworking fluids

INTRODUCTION

Potential demographic risk factors for outbreaks of respiratory disease due to water-based metalworking fluids (MWFs) were investigated through systematic review of published outbreak investigations.

METHODS

Search terms were selected by a multidisciplinary team, assisted by an experienced library information service. Several computerized literature databases were searched for articles published between January 1990 and October 2011, relating to ill health outbreaks due to MWFs. Papers meeting the search criteria were reviewed in detail, and their references checked for additional articles. Study design and demographic details of the outbreak were extracted from the selected articles and entered into standardized evidence tables.

RESULTS

Thirty-five articles relating to investigations of 27 outbreaks of respiratory ill health attributed to MWF exposure were identified. The majority of reports were case series of disease or observational cross-sectional studies of symptoms and hygiene measurements. Eight of the outbreak investigations included an element of case-control analysis. Most outbreaks were from the USA, had occurred in large car- or aeronautical-manufacturing plants, and were associated with the use of central shared sumps. Hygiene studies have not demonstrated consistent risk factors for respiratory outbreaks, in terms of the type of MWF utilized, degree of microbial contamination, or levels of personal exposure. Six studies were identified that found workers with MWF exposure during outbreaks were more likely to report respiratory or systemic symptoms than unexposed control workers. Six case-control analyses were also identified that found workers with extrinsic allergic alveolitis (EAA) were more likely to demonstrate certain immune responses to microbial contaminants and/or used MWFs than workers without EAA.

CONCLUSION

Despite a number of detailed workplace and immunological studies of asthma and alveolitis outbreaks in MWF-exposed workforces, our understanding of their aetiology remains limited.