Social inequalities in pure-tone hearing assessed using occupational stratification schemes

Abstract

Objective: The objective of this study is to analyse the performance of two occupational stratification approaches and the impact of social position on adult hearing. Design: The prevalence of hearing impairment, pure-tone averages (PTA) and prevalence ratios (PR) for relative hearing loss, which focuses on the position of one’s PTA in the age- and gender-specific distribution, were compared in groups defined by ISCO Skill Level and the International Socio-Economic Index (ISEI). Study sample: About 1571 subjects aged 30–89, including 677 highly screened adults, from the cross-sectional study HÖRSTAT. Results: ISCO Skill Level and ISEI yielded qualitatively the same results. The prevalence difference between the socially least and most advantaged group ranges between 10 and 16%, varying with the scheme applied. Low- and high-frequency PTA and PR for relative hearing loss confirm the gradient. Screening reduced, but did not negate the social differences. The prevalence difference dropped to 6–7% in the otologically normal subsample. Conclusions: Social groups defined by hierarchical, occupational measures differ in their pure-tone hearing, even if the main risk factors are controlled for. This underlines the need for population-based sampling, the relevance of reporting the study group’s social composition and the importance of advancing the discussion on appropriate social measures in hearing research.

Key Words:

• Hearing loss
• epidemiology
• social stratification
• occupational measures
• age
• gender
• otologically normal

Acknowledgements

Special thanks to ENT specialist Prof. Dr. Karsten Plotz, the students at the Institute of Hearing Technology, and the participants for their collaboration. Language services were provided by www.stels-ol.de.

Declaration of interest

Data collection was funded by the Lower Saxony Department of Science and Culture and the European Regional Funding (EFRE) with HÖRSTAT, HURDIG and the research fund of the Jade University of Applied Sciences. Further analysis was financed from the federal resources of Niedersächsisches Vorab by the Ministry of Science and Culture of Lower Saxony within the research focus “Hearing in everyday life (HALLO)”. The authors declare no conflict of interest.