Extended mortality follow-up among men and women in a U.S. furniture workers union

Our plain-English summary of Extended mortality follow-up among men and women in a U.S. furniture workers union, by B.A. Miller, A. Blair, E.J. Reed (American Journal of Industrial Medicine, 1994).

The study

• Authors: B.A. Miller, A. Blair, E.J. Reed
• Journal: American Journal of Industrial Medicine
• Published: 1994;25(4):537-49
• Cited by: 26 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

The addition of 5 years of follow-up and over 411,000 person-years of observation to a cohort of 34,081 men and women employed in U.S. furniture and other related industries allowed the investigation of mortality patterns among women and minority races in addition to white men. A significant excess of pleural mesotheliomas occurred among white men (standardized mortality ratio [SMR] = 3.7, 95% confidence interval [CI] = 1.2-8.7) but could not be linked to a particular type of furniture manufacturing. SMRs for myeloid leukemia and chronic nephritis were elevated among white men employed in the wood furniture industry but were not statistically significant. Males in the black/other race categories in wood furniture plants showed nonsignificant mortality excesses for infectious diseases and cancers of the prostate and colon and rectum. Among white women employed in wood furniture plants, mortality was elevated for cancers of the pancreas and lung during the most recent follow-up period. In metal furniture plants, mortality was raised among men in both race groups for kidney cancer (black/other SMR = 8.0, 95% CI = 1.6-23.2; white SMR = 2.1, 95% CI = 0.4-6.2) and diabetes mellitus (black/other SMR = 2.2, 95% CI = 0.6-5.6; white SMR = 1.8, 95% CI = 0.7-3.9). Stomach cancer mortality was significantly elevated (SMR = 3.3, 95% CI = 1.3-6.8) among white men in metal furniture plants and was of the same magnitude over both the previous and the most recent follow-up periods. Among those working with textiles, SMRs were significantly elevated for leukemia (SMR = 6.1, 95% CI = 1.2-7.8) and cancers of the colon and rectum (SMR = 3.2, 95% CI = 1.3-4.5) for white women. Lung cancer mortality was increased for white men and women in textile operations, but SMRs were not statistically significant. SMRs for a number of other causes of death that were elevated at the end of the earlier follow-up period were not increased during the new follow-up period.

In plain English

This study added 5 years of follow-up to a cohort of 34,801 men and women. All were first employed between 1946 and 1962 in union-organized U.S. shops and were found through United Furniture Workers of America insurance records. Most worked in furniture and related plants, but about 1% held nonmanufacturing jobs such as union staff. Deaths were counted through January 1, 1984 and compared with expected numbers based on U.S. population death rates. Overall, each race and sex group had 20 to 40% fewer deaths than expected. White men had a statistically significant excess of pleural cancer (five deaths; SMR 3.7, 95% CI 1.2-8.7), which the authors presumed were mesotheliomas. The excess could not be linked to a particular type of furniture manufacturing. The authors said they lacked the information to tell whether these men had been exposed to asbestos, in the furniture industry or elsewhere. Among workers followed 20 or more years, stomach cancer was significantly elevated in white men in metal furniture plants. Leukemia and colorectal cancer were significantly elevated in white women working with textiles. The authors noted that missing work histories and broad exposure groups likely misclassified workers.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Retrospective cohort mortality study (extended follow-up of an earlier report), comparing observed deaths with those expected from U.S. population rates (standardized mortality ratios)
• Who was studied: 34,801 members of the United Furniture Workers of America first employed in union-organized U.S. shops between 1946 and 1962: 22,755 white men, 5,366 black/other men, 5,291 white women and 1,389 black/other women. Subjects came from 37 states and the District of Columbia, with mortality follow-up to January 1, 1984. About 1% held nonmanufacturing jobs and were excluded from industry-specific analyses. Industry type could not be classified for 2%.
• Exposure: Employment in the furniture and related industries, grouped by type of plant (wood furniture, metal furniture, textiles, other products). Potential exposures named include wood and metal dusts, wood preservatives, formaldehyde, adhesives, solvents, welding fumes, spray paint, wood stains and lacquers. Asbestos exposure was not measured.
• Main results:
  • In the total cohort, overall mortality in each race and sex group was significantly lower than expected, by 20 to 40%.
  • White men had a significant excess of pleural cancer (SMR 3.7, 95% CI 1.2-8.7), which the authors presumed to be mesotheliomas. The excess could not be linked to a particular type of furniture manufacturing.
  • There were five pleural cancer deaths among white men, three of them after January 1979. Each man had worked for a different company: two in wood furniture plants, two in plants producing wood and metal furniture, and one in a metal furniture plant.
  • Among white men in metal furniture plants followed for at least 20 years, stomach cancer mortality was significantly elevated (SMR 3.3, 95% CI 1.3-6.8).
  • Among men in metal furniture plants, kidney cancer mortality was raised: black/other men SMR 8.0 (95% CI 1.6-23.2); white men SMR 2.1 (95% CI 0.4-6.2).
  • Among white women working with textiles and followed at least 20 years, colon and rectum cancer (SMR 3.2, 95% CI 1.3-4.5) and leukemia were significantly elevated. The leukemia deaths were all acute myeloid (SMR 17.9, 3 observed vs. 0.17 expected, 95% CI 3.6-52.2).
  • Among wood furniture workers followed at least 20 years, cause-specific mortality did not differ significantly from expected in any race and sex group. White men had nonsignificant twofold or larger SMRs for Hodgkin's disease, myeloid leukemia and chronic nephritis.
• The authors' conclusion: The authors concluded that the extra follow-up uncovered new associations. They also concluded that earlier excesses not seen again in the later period may have been tied to a specific time or exposure period, or may have been spurious. For pleural cancer, they stated they could not determine whether the men who died had been exposed to asbestos.
• Limitations the authors state:
  • There were no complete work histories, and broad exposure groups were used, which likely misclassified individuals and hindered detection of associations.
  • The authors lacked information on whether the men who died of pleural cancer were exposed to asbestos, in the furniture industry or elsewhere.
  • Furniture workers in North Carolina, which has few unionized plants, were underrepresented.
  • Deaths without a located death certificate were not assigned a cause, so some cause-specific mortality may be slightly underestimated.

Topics

Medical terms in this study, explained in our Lexicon: Pleural Mesothelioma, standardized mortality ratio (SMR), confidence interval, Stomach Cancer, Lung Cancer.

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