Socio-economic disparity in the global burden of occupational noise-induced hearing loss: an analysis for 2017 and the trend since 1990

Objectives To evaluate socio-economic disparity in the global burden of occupational noise-induced hearing loss (ONIHL) using disability-adjusted life-years (DALYs). Methods The numbers of DALYs due to ONIHL, age-standardised DALY rates and national human development index (HDI) data from 1990 to 2017 were collected. The relationship between the age-standardised DALY rates and the 2017 HDI was analysed. A concentration index (CI) and a relative index of inequality (RII) were calculated to evaluate the trend in socio-economic disparity in the burden of ONIHL for the period 1990–2017. Results From 1990 to 2017, the global DALYs due to ONIHL increased from 3.3 to 6.0 million, with the highest growth occurring in low-income countries (110.7%). Age-standardised DALY rates due to ONIHL were negatively associated with the HDI ( β = −0.733, p<0.001), and these rates were significantly higher in countries with a lower HDI. From 1990 to 2017, the trend in between-country inequality was flat with little fluctuation, the CIs stayed near −0.17, and the RIIs remained near 0.35. Conclusions Over the past few decades, low-income countries have experienced the most rapid growth in DALYs worldwide. A widening socio-economic disparity has persisted in the global burden of ONIHL, with a higher burden in lower socio-economic countries. These data suggest that more prevention programmes and healthcare services should be provided for developing countries.