- Published on 02 October 2013
Researchers at the Italian National Research Council working at the Milan Institute of Biomedical Engineering (ISIB) have developed a new screening method that is taking the analysis of how well people understand speech in noisy environments out into the real world.
It is being used more and more, including by academics worldwide, and has recently been highlighted in the American Journal of Audiology.
It all started with the observation that there are significant grey areas in adult hearing, ranging from the early stages of hearing loss to more obvious symptoms, and that it would be interesting to gain insight into these grey areas to ensure that patients are diagnosed as early as possible. But like all grey areas, they are poorly defined, often hard to pin down, and mostly neglected. The challenge successfully taken up by the group of researchers at the National Research Council, working at the Institute of Biomedical Engineering in Milan (ISIB) and now at the Institute of Electronics, Computer and Telecommunication Engineering (IEIIT), was therefore more technical than medical. Alessia Paglialonga (picture above) and Gabriella Tognola (picture below), under the guidance of Ferdinando Grandori, have designed and developed a new test for adult hearing screening specifically intended to examine hearing ability in one of the most difficult hearing contexts: understanding speech in noise.
The SUN Test, precisely for Speech Understanding in Noise, is a simple yet revolutionary analysis method that has already proven itself in thousands of patients of all ages, and not only within the neat confines of a laboratory, but rather out in the streets, in public spaces, in the environments where people live their day-to-day lives, thanks to specific important characteristics such as a basic support structure and a very short testing time.The test uses the intelligibility of single consonants through VCV (vowel-consonant-vowel) stimuli, and was initially assessed by other researchers at the Research Council, and by students, researchers, and lecturers at the Politecnico di Milano, where the Institute is located. Hundreds of volunteer subjects in all age groups also participated in the development phase in order to optimize the test procedure. In addition to the Italian test, several other language versions have been developed including English, German and French, and new versions in Portuguese, Spanish and Mandarin Chinese are currently being adapted.
Increasing scientific evidence shows that the priority for adult hearing ability screening is to identify day-to-day difficulties in realistic hearing conditions. To do this, we should no longer think solely in terms of measuring auditory sensitivity – as thresholds – but also auditory acuity, for example supra-threshold performance consisting of speech understanding in a context of background noise. Based on this principle, the objective of the experimental study of the SUN test was to develop a new speech-in-noise test to screen hearing in the adult population. Since development of the test was started in 2009, the research group has examined and tested a wide sample population of more than 6,000 subjects aged 14 to 95 years, characterized by various audiometric thresholds and configurations, either in controlled environments like laboratories, hospitals, clinics and pharmacies with low background noise, or in social environments including the network of universities of the third age, or in noisy open spaces (~ 65 dB A) such as streets, squares, and shopping malls.
The SUN method developed is an effective deafness screening test with specific features: it is fast, requires less than one minute per ear, even for older subjects, it is automated and easy to give and interpret, and is effective (thus reflecting real hearing difficulties in daily life), robust and stable even with high levels of background noise, and finally it is repeatable and reliable. It is based on recognition of a series of linguistic stimuli without meaning, produced in a context of background noise. There are three possible results with immediate visual significance, like traffic lights: green for “no hearing difficulty”, amber for “audiological testing advisable”, and red for “audiological testing recommended.”
It has been demonstrated that the SUN test confirms conventional clinical measurements of auditory function, that it is not influenced by patient age, and is not seen as complicated or difficult, meaning that it is well accepted. It works irrespective of the level of background noise and as a result of its flexible configuration, which can be adapted to platforms and portable devices, it is suitable for many different settings, from clinics to waiting rooms, from hearing centers to pharmacies.
The legacy of the AHS 2012 conference
The 2012 Adult Hearing Screening (AHS) conference provided a large, prestigious audience of colleagues from all over the world. Hearing screening for adults was the topic of the second edition of the event, organized by none other than the director of the research team, Ferdinando Grandori, and Alessia Paglialonga, and held in Cernobbio (Como) in June 2012. At this event, Alessia Paglialonga presented the SUN test to the participants on behalf of the group, along with its applications, and detailed the results of the testing program. It also provided an occasion for the Italian group to exchange with other professionals representing the worldwide state of knowledge in the area of hearing. A look at the regions where the participants came from shows just how representative the group was: 135 participants from Europe (52%) with all the others hailing from the rest of the world, some 45 professionals from Asia and the Middle East (17%), 42 from Canada and the United States (16%), 16 from the Australia-Pacific region (6%), 13 from South America (5%), and finally 11 from Africa (4%).
The legacy of the Como conference was even more valuable than the scientific and cultural experience shared by the participants. Several opinion leaders on the most current issues in audiology enthusiastically accepted an invitation from the local hosts to participate, with their own scientific contributions, in three research forums on hearing in adult and the elderly. The findings of these studies were published in the American Journal of Audiology in 2013. The first Research Forum, on “Hearing Screening in Adults and Older Adults” appeared in Volume 22(1) in June 2013, while the second and third Research Forums, on “Aging and Hearing: Mechanisms and Effects” and “Intervention and Rehabilitation Strategies for Adults and Older Adults” will appear in Volume 22(2) in December, but are for the most part already available on the online version of the Journal.The editor of the Journal, Larry E. Humes from the University of Indiana, highlighted the knowledge-sharing scope of the initiative, and said in his editorial that he is very pleased to improve access to emerging studies in audiology and to provide clinicians and researchers with such interesting avenues to explore as they move forward in their work. The forum involves remote scientific discussions on the topic of hearing screening for adults and the elderly, as explained in the introduction by Ferdinando Grandori and Alessia Paglialonga, and includes contributions from Adrian Davis and Pauline Smith from the UK on problems related to healthcare policies in the area of screening, from the Italian research team referring to the SUN Test, from a German group in Oldenburg led by Melanie Angela Zokoll that reports on various speech tests in noise for multilingual and diagnostic screening, from Barbara Weinstein from CUNY in New York who presents a toolkit for the study of otological function in screening of elderly subjects, from Chryssoula Thodi from the European University Cyprus who, on behalf of many other colleagues, signed a paper on monitoring and the results of audiological screening in adults, and finally from Anouk Linssen of the Maastricht University Medical Center and other Dutch researchers on the costs and benefits of a hearing screening and rehabilitation program in retirement homes for the elderly in the Netherlands.
Hearing in adults in Europe: AHEAD III
Ageing of the population in Western countries is now an established reality. By the year 2020, some 28% of the European population will be older than 60 years of age. In addition, according to the World Health Organization, hearing loss is the most common of the twenty causes of moderate to severe disability. 278 million people suffer from hearing impairment worldwide. Deafness is emerging as one the most important and common chronic health issues among adults, and its slow but progressive course contributes to the development of disabling conditions, almost without the patient even noticing. This is one of the reasons why both diagnosis and rehabilitation are often neglected. Screening programs are also inadequate in general, particularly since hearing loss is often considered to be a less serious problem in patients with a complex clinical state, which is commonly the case in elderly subjects. Nonetheless, there is greater commitment to ensuring that hearing tests become an increasing part of routine care. Various pilot projects concerning hearing in adults have been conducted in Europe over the past few years, and both test data and models that have been found to be effective are already available. It is important to note, moreover, that the value of a good method lies in measuring not only hearing loss, but specifically hearing disability, and to what extent the reduction in hearing performance affects general psychophysical conditions and the patient’s quality of life.
The three-year European project known as “AHEAD III - Assessment of Hearing in the Elderly: Aging and Degeneration - Integration through Immediate Intervention”, carried out in coordination with the European Commission and the Institute of Biomedical Engineering in Milan, has brought together 17 European partners and 28 independent research experts, with the aim of exploring strategies and new solutions for screening and treatment of hearing disability in adults and the elderly. On the basis of the ICF model (International Classification of Functioning, Disability and Health) of the World Health Organization, the experts have developed a new biopsycosocial model of hearing disability, taking into account the fact that physiological aspects of disability are only a part of the patient’s experience, and do not take into account their reactions, emotions and changes in their daily activities and relationships, for instance. The three different levels of disability that distinguish between the functioning of the body, daily activities, and the degree of participation, must entail three levels of rehabilitation.
A significant chapter of AHEAD III is dedicated to the causes and consequences of presbycusis, with a survey of etiological and epidemiological factors. The data collected will serve as a basis for future research on the anatomical and physiological degeneration of the auditory system. In addition, a review was conducted on all the scientific data presented in the literature concerning the psychological and social impact of deafness. The partners were then invited to develop a protocol for a hearing test with the aim of identifying in particular disorders of central auditory processing also in relation to age, for the longitudinal BASE II study, funded by the German Ministry of Education and Research, which will concern seventy-year-olds in the period 2009-2039.
Concerning methods and techniques for screening, various possibilities were considered: audiograms on pure tones, questionnaires, speech tests, tests of the central hearing system, acoustic otoemissions, auditory evoked potentials, online and telephone screening, genetic screening. All the methods were assessed on the basis of various factors: test target, sensitivity, specificity, reliability, duration, age limit, functional, skill or understanding requirements, need for training of patients and investigators, interpretation of results, dependency on education, culture or language of the subjects, need for a controlled environment to perform the test, ability to offer a pass/refer result, ease of use of technology, hygiene requirements, acceptance by patients, and costs per tested patient. Alongside the methods, the researchers also focused on intervention strategies following screening and, in this regard, a pilot project was conducted in Cyprus including more than two thousand elderly subjects from retiree organizations and social centers, and various other screening and intervention initiatives for adults and elderly subjects, many of which were developed in Italy. The AHEAD III project contributed to the creation of the first edition of the AHS international conference which was held in Cernobbio, Como, in 2010. It brought together specialists in audiology, ENT medicine, hearing sciences, communication disorders, biomedical engineering, psychology, genetics, neurology, geriatrics, health administration, epidemiology and other relevant areas, and launched the new tradition of organizing a broad and prestigious biennial event, that was repeated in 2012. Again in 2014, it will be proposed as part of the HEAL (HEaring Across the Lifespan)event, to take place again in Cernobbio, Lake Como from 5 to 7 June.
Audiology infos Italy
Photos: J. Cutler, C.P. Translation: Craig Stevens