Socioeconomic Inequality and Hearing Health in England: Examining the Relationship between Socioeconomic Inequality and the Development of Hearing Impairment and the Impact of Hearing Impairment on the Lives of Older Adults in England

Abstract

Hearing loss (HL) is a significant public health problem estimated to affect over 9 million adults in England. Its negative impact is broader than sensory impairment, as it also affects the mental wellbeing, the interpersonal interactions, and the participation of the individuals in society. There is potential for reducing the prevalence and consequences of HL by understanding the impact of socioeconomic inequality in hearing health, which is currently unclear. This thesis aimed to i) investigate the socioeconomic factors that are related to the development of HL in older adults in England; ii) assess the socioeconomic risks for access to hearing health services and hearing aid use among older adults; iii) examine whether there is a causal link between HL and depression in later life across different socioeconomic groups; and iv) assess whether the hearing aids usage alleviates the depressive symptoms associated with HL in older adults. The investigation initiated through a critical interpretive synthesis (CIS) review, which led to the formulation of the Conceptual Model for Hearing Health Inequalities (HHI Model). This model depicts the specific mechanisms for hearing health and their evolution over time. Then, using data from the English Longitudinal Study of Ageing, I conducted other four empirical studies: I present the first study that examined the association of objectively measured HL in older adults in England with four different socioeconomic position (SEP) indicators (education, occupation, income and wealth) and several modifiable lifestyle factors. The study showed that HL among older adults is as strongly associated with socioeconomic and lifestyle factors as with core demographic risk factors such as age and gender. Next, I provided time-series analyses of the regional patterns and trends of HL in England, which showed that between 2002 and 2017 there was an estimated increase of 10.2% in the total HL prevalence among the older English population. Even though the samples had similar age profiles, they differed markedly on their HL outcomes, both regionally and chronically. The findings revealed that the increase in HL prevalence is not related to the ageing of the population, as widely believed, but is potentially due to social and lifestyle changes. Next, I explored the concordance of self-reported measures of hearing difficulty with objective data on hearing, measured by a handheld audiometric screening device; this showed that one-third of over-50s may be unaware that have HL and remain undiagnosed. Lastly, across different socioeconomic groups, I examined the longitudinal relationship between HL and depressive symptoms in later life, and whether the use of hearing aids alleviated these symptoms. A graded relationship between HL and depression according to SEP was revealed, with those with HL in the lowest wealth groups experiencing up to double the relative risk of depression compared with those in the highest wealth quintile. Those in the lowest versus the highest wealth quintiles experienced more considerable improvement in their psychosocial wellbeing with the use of hearing aids, and the improvement was slightly greater with the most frequent use of hearing aids. This thesis resulted in several novel findings that can bring rich insights to the fields of audiology, population health research and health policy. A new conceptualisation of HL is proposed, which argues that HL is not necessarily an inevitable accompaniment to ageing but a preventable lifestyle disease. These findings call for an effective and sustainable HL screening strategy for the early detection of, and intervention for, HL in older adults. A socio-spatial approach is crucial for planning sustainable models of hearing care based on actual needs. The thesis also has novel clinical implications, as it adds to the understanding of the interrelationship between HL and depression, and the impact that hearing aids have. The findings can inform

Date of Award	1 Aug 2021
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Darren Ashcroft (Supervisor), Evangelos (Evan) Kontopantelis (Supervisor) & Maria Panagioti (Supervisor)