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. 2018 Jul 11;18(1):862.
doi: 10.1186/s12889-018-5749-2.

Precarious transition: a mortality study of South African ex-miners

Kim Bloch  1 , Leigh F Johnson  2 , Mlindeli Nkosi  3 , Rodney Ehrlich  4
Affiliations

Precarious transition: a mortality study of South African ex-miners

Kim Bloch et al. BMC Public Health. .

Abstract

Background: Despite their burden of a triple epidemic of silicosis, tuberculosis and HIV infection, little is known about the mortality experience of miners from the South African mining industry once they leave employment. Such information is important because of the size and dispersion of this population across a number of countries and the progressive nature of these diseases.

Methods: This study included 306,297 South African miners who left the industry during 2001-2013. The study aimed to calculate crude and standardised mortality rates, identify secular trends in mortality and model demographic and occupational risk factors for mortality.

Results: Crude mortality rates peaked in the first year after exit (32.8/1000 person-years), decreasing with each year from exit. Overall mortality was 20% higher than in the general population. Adjusted annual mortality halved over the 12 year period. Mortality predictors were being a black miner [adjusted hazard ratio (aHR) 3.30; 95% confidence interval (CI) 3.15-3.46]; underground work (aHR 1.33; 95% CI 1.28-1.39); and gold aHR 1.15 (95% CI 1.12-1.19) or multiple commodity employment (aHR 1.15; 95% CI 1.11-1.19).

Conclusions: This is the first long-term mortality assessment in the large ex-miner population from the South African mining industry. Mortality patterns follow that of the national HIV-tuberculosis epidemic and antiretroviral treatment availability. However, ex-miners have further elevated mortality and a very high mortality risk in the year after leaving the workforce. Coordinated action between the mining industry, governments and non-governmental organisations is needed to reduce the impact of this precarious transition.

Keywords: HIV; Mining; Mortality; Silicosis; South Africa; Tuberculosis.

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Conflict of interest statement

Ethics approval and consent to participate

The study was approved by the Human Research Ethics Committee of the Faculty of Health, University of Cape Town (ref. 309/2013). As this was an anonymised secondary data source retrospectively spanning 40 years, the requirement for individual informed consent was accepted as non-applicable. The data were made available by TEBA Ltd., Johannesburg, a private company (www.teba.co.za), and are not publicly available. There was no restriction on publication.

Competing interests

Prof. Ehrlich has written expert reports for plaintiff lawyers in silicosis litigation proceedings. The other authors report no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
Crude mortality rate among South African miners by year since exit from the industry, 2001–2013 (n = 306,297). Each point on the curve represents the mortality rate over the preceding year, e.g. year 2 refers to the rate over the period 1.0–1.9 years after exit. Year 13 is an incomplete year. See Additional file 1: Table S1
See this image and copyright information in PMC

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