«THE ECONOMIC IMPACT AND COST OF HEARING LOSS IN AUSTRALIA A report by Access Economics Pty Ltd February 2006 Listen Hear! The economic impact and ...»
A conservative approach has been taken in the estimate of DALYs. The estimate is based on hearing loss in the better ear (a truer reflection of disability), does not include hearing loss in the Deaf Community (using the estimate of 10,000 people or less than 1% of people with hearing loss), takes into account the gains from wearing hearing aids and makes the most conservative assumptions regarding prevalence among young adults.
Projections and further work
Projections of hearing loss suggest that hearing loss in the worse ear is expected to more than double by 2050 (a 2.2-fold increase).
The prevalence of hearing loss overall is projected to increase from 17.4% (one in six) in 2005 to 26.7% (more than one in four) in 2050.
The prevalence of hearing loss is projected to increase from 21.0% (one in five) in 2005 to 31.5% of all males (nearly one in three, largely as a result of demographic ageing) in 2050.
A significant amount of hearing loss (37%) is due to excessive noise exposure, which is preventable.
Further research is warranted in the following areas:
epidemiology of hearing loss prevention of hearing loss (cost-effective measures), in particular barriers to adoption of personal protection equipment;
bio-molecular and genetic approaches to hearing loss;
enhancing access to, and continued use of, hearing aids;
health effects of hearing loss;
cost-effective models of enhancing informal care;
aboriginal hearing health; and enhancing productivity of people with hearing loss.
1. STUDY CONTEXT 1.1 THE NEED FOR THIS STUDY Hearing is one of our primary senses. Together with vision and touch, hearing enables humans to interact with our environment at all levels. Of the three primary senses, hearing is the foundation sense used for communication between people. A loss of hearing acuity fundamentally limits the ability of the individual to communicate, and through this, limits their ability to interact with society. This has social and economic consequences both for the individual and for society.
The social consequences of a hearing loss have varied over human history. In Ancient Greece, hearing loss denied a person the right to participate in community life (Edwards, 1994). Similarly in Biblical times, deaf people were treated as social outcasts and survived primarily by begging. In Medieval times, Lane (1984) notes “the inability to speak or hear meant that the individual was not a person in law and therefore could not inherit the family fortune or participate in Church life.” However, hearing loss was not a total barrier to work in medieval times since the work undertaken was farm, village or craft-based (Hogan, 1996).
The advent of the industrial revolution and subsequent urbanisation resulted in an unravelling of traditional medieval social systems. Rapid urbanisation created a variety of social problems in the nineteenth century and concern for social order became paramount. As a result of these concerns, people with disabilities, including hearing loss, were often institutionalised and undertook labour in workhouses (Bentham, 1816, Kannar, 1964; Dean, 1992; Fusfeld, 1994; Hogan 1996). Several movements to educate deaf people to take their place in society emerged in the late nineteenth century. Students who graduated from these systems predominantly found employment in the trades (Winefield, 1987).
Ruben (2000) observes that at the beginning of the twentieth century, work was predominantly manual and easily undertaken by people with communication disorders like hearing loss. In the United States, only 20% of people were employed in white collar jobs where communication skills formed an essential part of the job requirement.
However, as the twentieth century evolved the nature of work changed again. Ruben observes that by the end of the twentieth century “62% of (the) labor force made their livelihood using skills based on their communication abilities”.
Data produced by the Australian Bureau of Statistics shows a similar trend in Australia with a substantial growth in service industries jobs compared with, for example, the manufacturing sector. 1 The Bureau observes that 54% of people born 1927-1931 worked in the services industry compared with 74% of people born 1957-1961. Ruben (2000) studied the economic effect of communication disorders and the subsequent cost of lost or degraded employment opportunities in people who lacked the ability to hear or to talk without problems. He estimated the cost to the American economy to be between 2.5% and 3% of GDP. Ruben concluded his study with the observation that a person without communication skills was not only likely to be unemployed, but 1 http://www.abs.gov.au/Ausstats/abs@.nsf/0/C39B360652A7A8BFCA256D39001BC355?Open accessed 25/01/06.
unemployable in the modern era. With an increasing move to a service-based economy, people with hearing loss in Australia face similar challenges.
As well as limiting potential employment prospects, hearing loss places limitations on the individual’s ability to interact with the community.
Although hearing loss affects 1 in 6 Australians, to date there has been no definitive research on its economic impact. Most studies have focused on prevalence issues, or delineating the social context of hearing loss to the individual and to some groups (for example workers suffering industry-based noise-induced hearing loss).
Given acceptance of the tenet that Australians must stay productive longer into their working lives, and the ever-escalating costs of health services for our ageing Australian population, any disorder or problem that places limitations on productivity and healthy ageing is of concern. As such, awareness of the economic costs of hearing loss is an important issue in public health, particularly in the context of comparing the costs of (preventive or therapeutic) interventions with those of not intervening.
Few attempts have been made to establish the consolidated costs of hearing loss in the wider community using sound economic techniques, and to the best of our knowledge, this has never been undertaken in Australia.
The aim of this study was therefore to estimate the economic impact and cost of hearing loss in Australia in 2005.
In commissioning this study, the Cooperative Research Centre for Cochlear Implant and Hearing Aid Innovation (CRC HEAR) and the Victorian Deaf Society (Vicdeaf) first posed the question “How much does deafness cost the Australian community?” There were a number of obstacles confronted in answering this question.
First, hearing healthcare services are fragmented between Commonwealth and Statebased agencies, and between the public and private sectors. There is no coordinated overall hearing healthcare program across Australia, and as such, there are no detailed estimates of the overall costs of deafness that include all sources of expenditure. The education sector is also strongly involved in the remediation of hearing loss.
A more fundamental problem arises in that, although Australian Hearing Services (a Commonwealth statutory authority) has been established to provide hearing healthcare services to children, pensioners and ATSIC peoples, hearing health care is not considered to be a priority health care area. Hearing aids are not treated as essential medical appliances, reflected in the differential services provided under auxiliary cover by private health funds for hearing services and appliances.
In addition, although there is general acceptance that preventive measures – such as good education, ear protection and information about how to preserve hearing and how to avoid noise-induced hearing loss when working in noisy environments – should be readily available and provided as the norm in industry, the approaches to dealing with hearing conservation vary between States/Territories, and there is no consolidated Australia-wide awareness or public health program. This contrasts with skin cancer or other health conditions where there is a large role for prevention activities.
In considering economic costs, the loss of effectiveness and productivity in the workforce as a result of hearing loss and its associated communication problems are a key consideration. Additional health-related problems associated with hearing loss,
such as tinnitus and/or balance disorders, may also compromise the individual’s productivity and contribution to society.
For children, hearing loss poses additional difficulties, in that the sense of hearing is critical not only to development of auditory skills (such as localising sounds and comprehending the meaning of an acoustic message), but also to the development of spoken language, and most importantly to the development of speech and language.
Hearing loss impacts directly on literacy and learning, education, and employment options for children.
To address these many issues, Access Economics was commissioned to provide a comprehensive economic analysis of the costs and economic impact of hearing loss in Australia. The commission required Access Economics to conduct an independent disease cost burden analysis of hearing loss in Australia. This study would estimate two key figures: the financial cost associated with hearing loss and the Australian economy and the cost of the loss of wellbeing to individuals as a result of hearing loss.
1.2 STRUCTURE OF THIS STUDY The structure of the study was agreed to between Access Economics and the project stakeholders. A prevalence approach was adopted for the study, given the available epidemiological data and literature.
Prevalence rates in 2005 in Australia were estimated in the better and worse ear by:
gender; and severity of hearing loss.
The prevalence of hearing loss was projected to 2050 based on ABS population projections.
Costs associated with hearing loss were examined comprising:
direct health costs;
other financial costs incurred due to hearing loss, including:
education and support services;
communication aids and devices;
carers; and the deadweight losses associated with government transfer payments; and loss of wellbeing (burden of disease), measured in terms of DALYs (an internationally accepted non-financial measure) as well as being converted to a dollar metric using willingness to pay methodology and applying the concept of the value of a statistical life (VSL), based on wage-risk studies.
Sources of data for indirect costs were identified in collaboration with a broad range of service providers and government departments.
2. BACKGROUND 2.1 THE HEARING SENSE The human body has five senses "which serve as receivers of stimulation from outside the body...the ear is the end-organ for hearing" (Myklebust, 1971:11). Sound waves travelling through the air are gathered in the outer part of the ear (called the pinna), travel through the auditory canal and pass through the ear drum (tympanic membrane) to what is commonly known as the middle ear. Sound waves set up vibrations of the tympanic membrane which separates the outer and middle ear. These vibrations are transformed via three small bones commonly known as the hammer (malleus), anvil (incus) and stirrup (stapes) (also known as the ossicular chain) so as to permit vibration of the fluid which fills the inner ear (the cochlea). The fluid filled cochlea resembles a snail shell. Inside it are thousands of tiny hair cells called cilia. These hair cells have been compared to new lawn which has just grown from seed. As grass moves to and fro in the wind, the cilia move to and fro in response to movements in the inner ear fluid which has been vibrated by incoming sound. Movement of the cilia discharges an electrical activity in the neurons that form the eighth cranial nerve, which connects the receptor surface of the cochlea with the central nervous system. Through developmental learning processes, differing forms and sequences of sound ultimately become associated with different events, objects and meanings. A person's ability to understand this variety of events, objects and meanings produced by sound is usually called hearing (Schubert, 1980). The key reason that people seek help for hearing loss is to be able to hear speech more clearly (Dillon, 2001).
Source: http://kidshealth.org/kid/body/ear_noSW.html 2.2 SEVERITY OF HEARING LOSS Hearing can be described by the range of sounds one can hear (for example the lowest to the highest piano note) and how softly one can hear such sounds. The range of sounds is measured in hertz or number of sound waves per second. The intensity or strength of a sound is given in terms of a scale of decibels which usually ranges from 0 to 140 decibels where 0 decibels represents the quietest level of hearing accessible to
the average healthy human ear2 and 140 decibels, where physical damage immediately occurs (Table 2-1). Decibels are measured using a logarithmic scale. On an ordinary or linear scale, an increase say from a score of 50 to a score of 100 would equal a doubling of intensity. However, on a decibel scale, an increase of 6dB equates to a doubling of intensity.
Noble (1978:174) points out that the concept of normal hearing is useful for ascertaining the extent of injury to hearing from factors such as workplace noise.
Levels of hearing loss are commonly referred to as mild, moderate, severe or profound, depending on how intense a sound has to be before one can hear it. In this analysis, measured hearing loss by severity is defined (as per Australian Hearing, 2005) for
children aged less than 15 years as:
Mild 0-30 dB;
Moderate 31-60 dB;
Severe 61-90 dB;
Profound 91 dB plus;
and, for people aged 15 years or more (as per Wilson, 1997) as:
Mild 25 dB and 45dB;
Moderate 45 dB and 65dB; and Severe 65 dB.