Effects of hearing loss and hearing aids on quality of life and cognitive decline Harvey Dillon, Gitte Keidser National Acoustic Laboratories and The Hearing Cooperative Research Centre Better Hearing National Conference 2013 Impact of untreated hearing loss on health • Proven links between hearing loss and: – depression / mood / emotional state – social isolation, loneliness, withdrawal – self-sufficiency – cognitive ability – physical and psychological well-being – life expectancy • Asserted links between hearing loss and: • anxiety • anger / irritation • paranoia • distress / fear • exhaustion • embarrassment • insecurity • unemployment • loss of group affiliation • restricted travel • loss of intimacy Effects of hearing loss? Hearing loss Mortality Cardio-vascular disease Depression Activity restriction We just can’t deduce causation from these surveys of health Effects of hearing aids? Mortality Depression Hearing loss Isolation Anxiety Insecurity etc Cross-sectional studies Hearing loss Better: Less isolation. More able to deal with problems Mood / less depression Emotional state Self-sufficiency Social relationships Hearing loss and hearing aids Life expectancy Cross-sectional studies Fatalistic people (external locus of control) Hearing loss Better: Pro-active people (internal locus of control) Mood / less depression Emotional state Self-sufficiency Social relationships Hearing loss and hearing aids Life expectancy Cross-sectional studies Unwell people, with hearing loss Attend to major sickness Hearing loss Attend to hearing loss Better: Healthy people, with hearing loss Mood / less depression Emotional state Self-sufficiency Social relationships Hearing loss and hearing aids Life expectancy Hearing loss, hearing aids and cognitive decline Longitudinal studies Better: + Social relationships Cognitive functioning Memory Hearing loss Learning ability Less depression Less paranoia Mulrow et al (1990); Dye & Peak (1983) Longitudinal study: Lin et al (2013) Johns Hopkins Centre, USA Sample • 1,984 adults, mean age =77 years, no dementia • 58% had hearing loss (>25 dB 4FA in better ear) • Cognitive ability measured 6 years later Results • Those with hearing loss had rate of cognitive decline 37% greater than those with no loss • Rate of decline increased significantly with hearing loss • Rate of decline much less for those with hearing aids, but difference not statistically significant & not randomised – Adjusted for age, sex, race, education, smoking status, hypertension, diabetes mellitus, stroke history – Cause and effect likely but not proven Rate of cognitive decline per year Effect of hearing loss on cognitive decline Rate of cognitive decline per year * * Beneficial effect of hearing aids Effects of hearing loss Isolation Hearing loss Poor speech understanding Poor Working memory Something else Cognitive decline, dementia UK Biobank • Extensive data on over 100,000 people • Aged 40 to 69 years • Relation of hearing loss to other factors being analysed by Dr Keidser at NAL • Attempting to investigate path from hearing loss to depression and cognitive abilities by statistical methods UK Biobank data No hearing loss Hearing loss Hearing loss in the future Proportion of population with >=25 dB 4FAHL Percentage of population 25.0% 20.0% 70 & over 15.0% 60-69 10.0% 50-59 5.0% 15-49 0.0% 2003 2006 2011 Year 2021 2031 Why do people hear but not understand? ….. and what NAL is doing about it Noise damaged Good What can go wrong? The hair cells can die (noise, drugs, age) Vowel spectra and audibility Sound level oo ee 250 First formant 500 Second formant 1000 2000 Frequency (Hz) 4000 Reduced dynamic range with hearing loss Too loud Intense Moderate Weak Too soft (a) Norm Too loud Intense Moderate Weak Intense Moderate Weak (b) Too loud Too soft (c) Sam Too soft Prescribing hearing aids to maximise intelligibility and control loudness NAL-NL2 (2011) NAL-NL1 (1999) NAL-RP (1991) NAL-R (1986) NAL (1976) Deficit (VCV & CUNY), HL, Q10, OAE, TEN, Cog, & Age: 5600 Hz low pass es-SIIeff (VCV Avg(QH QL N) LP5600) SIIdes-SIIeff (CUNY Avg(QH QL N) LP5600) L56HL Q10 LP56 COAE L56 EL LP56 Cognition AgeLim But hearing is still not normal! Sound level Frequency resolution in hearing loss (a) Excitation 250 1000 4000 1000 4000 (b) 250 Frequency (Hz) Super-directional microphones NAL binaural beamformer + + Right Front Beamformer and DOA Delay Right HRTF DOA Left + + Mejia Left To CAPD To end Outcomes of children with hearing impairment Teresa YC Ching, and team We measure outcomes as children grow, … Outcomes • Expressive Communication • Auditory comprehension • Receptive vocab. • Expressive vocab. • • • • Language Speech creating sound valueTM Articulation Phonological dev Speech perception Spatial release from masking • • • • Reading Writing Math reasoning Numerical operations Literacy & numeracy • Aural-oral function in real life • Pragmatics • Strengths and difficulties • Educational attainment • Employment Psychosocial skills Education & employment T Ching, NAL, HEARing CRC At 5 years, early CI linked to better outcomes (n = 104) creating sound valueTM T Ching, NAL, HEARing CRC So baby, how does it sound? Objective hearing aid evaluation for: • young infants • difficult-to-test people 35 HearLab Hearing disorders in the brain Parietal lobe Frontal lobe Occipital lobe Temporal lobe Sylvian fissure Superior temporal gyrus Spatial Processing Disorder Lack of spatial release from masking Noise Noise Speech Noise Noise Cameron, Dillon & Newall LISN & Learn Game Target at 0˚: Distracters at + and -90˚: Target: The horse kicked six wet shoes LiSN & Learn SRT (dB) Better LiSN & Learn - Performance Over Time (n=9) 10 dB Cameron & Dillon (2011) Randomized Control Trial Cameron, Glyde & Dillon (2012) Lisn & Learn N=5 Earobics N=5 3 Pre-training Post-training 2 1 0 -1 -2 (Population Standa LiSN-S Score -3 -4 -5 -6 Low Cue Talker Adv Total Adv High Cue Spatial Adv Low Cue Talker Adv Total Adv High Cue Spatial Adv Group: LiSN & Learn Group: Earobics Future research Central processing disorders in elderly people Blue Mountains Study: Golding et al (2004) • Studied 1576 people > 55 years • Battery of 7 tests • 76% failed 1 or more tests • 64% failed 2 or more tests But can we give training to overcome it? Thanks for listening www.NAL.gov.au Volunteers needed ! NAL is funded by the Federal Department of Health, Office of Hearing Services.