Results from a Ukrainian-US collaborative study: prevalence and predictors of respiratory symptoms among Ukrainian coal miners.

BACKGROUND

Underground coal mining is an expanding industry in Ukraine, yet little is known about the burden of respiratory disease among Ukrainian miners.

METHODS

A Fogarty International Center-supported collaboration between researchers at the University of Illinois and the Institute of Occupational Health in Kyiv, Ukraine formed to improve capacity for conducting and monitoring medical surveillance among Ukrainian coal miners. A cross-sectional survey among a random sample of working and former miners was conducted; demographic, work, and health information were collected using a standardized questionnaire. Weighted prevalence rates were calculated and predictors of respiratory symptoms explored.

RESULTS

Improvements in infrastructure, including spirometry and chest radiography testing, transformed medical surveillance among these miners. Results from the health study included that the prevalence of respiratory symptoms was higher among former compared to current miners (shortness of breath 35.6% vs. 5.1%; chronic bronchitis 18.1% vs. 13.9%, respectively). A statistically significant exposure-response relationship was observed between years mining and respiratory symptoms in former miners and between years mining at the coal face and respiratory symptoms among current miners. Evidence of downward bias from the healthy worker survivor effect was observed.

CONCLUSIONS

This successful international collaboration built a sustainable infrastructure for conducting workplace medical surveillance and research. The resulting study was the first in the western literature to report on respiratory symptoms in this population; likely underestimation of disease rates due to selection and measurement biases was demonstrated. Efforts should continue to build this collaboration and to characterize and reduce respiratory illness among Ukrainian coal miners.