PowerPoint Presentation

Effects of hearing loss and hearing aids on quality of life and cognitive declineHarvey Dillon, Gitte Keidser

National Acoustic Laboratories and The Hearing Cooperative Research Centre

Better Hearing National Conference2013

Impact of untreated hearing loss on health Proven links between hearing loss and:depression / mood / emotional statesocial isolation, loneliness, withdrawalself-sufficiencycognitive abilityphysical and psychological well-being life expectancyanger / irritationdistress / fearembarrassmentunemploymentrestricted travel

Asserted links between hearing loss and: anxiety paranoia exhaustion insecurity loss of group affiliation loss of intimacy

Effects of hearing loss?Hearing lossDepressionMortalityCardio-vascular diseaseActivity restrictionWe just cant deduce causation from these surveys of healthEffects of hearing aids?Hearing lossMortalityDepressionIsolationAnxietyInsecurityetcCross-sectional studies

Hearing loss

Hearing loss and hearing aidsLess isolation.More able to deal with problemsBetter:Mood / less depressionEmotional stateSelf-sufficiencySocial relationshipsLife expectancy

Cross-sectional studies

Hearing loss

Hearing loss and hearing aidsBetter:Mood / less depressionEmotional stateSelf-sufficiencySocial relationshipsLife expectancy

Pro-active people(internal locus of control)Fatalistic people(external locus of control)Cross-sectional studies

Hearing loss

Hearing loss and hearing aidsUnwell people, with hearing lossAttend to major sicknessHealthy people, with hearing lossBetter:Mood / less depressionEmotional stateSelf-sufficiencySocial relationshipsLife expectancy

Attend to hearing lossHearing loss, hearing aids and cognitive declineLongitudinal studies

Hearing lossBetter:Social relationshipsCognitive functioningMemoryLearning abilityLess depressionLess paranoia

+Mulrow et al (1990); Dye & Peak (1983)Longitudinal study:Lin et al (2013) Johns Hopkins Centre, USASample1,984 adults, mean age =77 years, no dementia58% had hearing loss (>25 dB 4FA in better ear)Cognitive ability measured 6 years laterResultsThose with hearing loss had rate of cognitive decline 37% greater than those with no lossRate of decline increased significantly with hearing lossRate 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 historyCause and effect likely but not provenRate of cognitive decline per year

Effect of hearing loss on cognitive declineRate of cognitive decline per year

**Beneficial effect of hearing aidsEffects of hearing lossHearing lossPoor speech understandingIsolationSomething elsePoor Working memoryCognitive decline, dementiaUK BiobankExtensive data on over 100,000 peopleAged 40 to 69 yearsRelation of hearing loss to other factors being analysed by Dr Keidser at NALAttempting to investigate path from hearing loss to depression and cognitive abilities by statistical methodsUK Biobank data

No hearing lossHearing lossAged-care facilitiesHearing lossAppearance of dementiaReduced auditory stimulationCognitivedeclineActual dementia ??Improved services Improved quality of lifeHearing loss in the future

Why do people hear but not understand?.. and what NAL is doing about it

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GoodNoise damaged20This is a close-up of some healthy, and some damaged hair cells.What can go wrong?

The hair cells can die (noise, drugs, age)21Heres a photo of the three rows of outer hair cells and one row of inner hair cells in a healthy cochlea.

Too much noise destroys the hairs and hair cellsSound levelFirst formantoo25010004000Frequency (Hz)5002000eeSecond formantVowel spectra and audibility

IntenseModerateWeakTooloudToosoftNorm

(a)SamIntenseModerateWeakTooloudToosoft(b)IntenseModerateWeakTooloudToosoft(c)Reduced dynamic range with hearing lossFigure 1.2 The relationship between the dynamic range of sounds in the environment and the dynamic range of hearing for: (a) normal hearing, (b) sensorineural hearing loss without amplification, and (c) sensorineural hearing loss with a constant amount of amplification for all input levels.

23Prescribing hearing aids to maximise intelligibility and control loudness

NAL-NL2 (2011)NAL-NL1 (1999)NAL-RP (1991)NAL-R (1986)NAL (1976)

But hearing is still not normal!10002504000Sound level(a)10002504000Frequency (Hz)Excitation(b)Frequency resolution in hearing lossNAL binaural beamformer++FrontLeftRightDelayBeamformer and DOA

HRTF

DOARightLeft++Super-directional microphonesTo endTo CAPDMejia Outcomes of children with hearing impairmentTeresa YC Ching, and team

We measure outcomes as children grow,

First Voice MeetingT Ching, NAL, HEARing CRCOutcomesT Ching, NAL, HEARing CRC creating sound valueTM T Ching, NAL, HEARing CRC

Implant age: p = 0.0006At 5 years, early CI linked to better outcomes(n = 104)

creating sound valueTM

35So baby, how does it sound?Objective hearing aid evaluation for: young infantsdifficult-to-test people

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HearLabSpatial Processing Disorder

NoiseNoiseNoiseNoiseSpeech

Lack of spatial release from maskingCameron, Dillon & NewallPrevious research at NAL has shown that a number of children with suspected APD have difficulty separating sounds that arrive simultaneously at the ears from different locations.

Tendency to affect children with history of COM.

Deficit likely related to ability to use binaural (ITD; IID) cues

38LISN & Learn Game

Target at 0:Distracters at + and -90:

Target: The horse kicked six wet shoesLiSN & Learn - Performance Over Time (n=9)LiSN & Learn SRT (dB)10 dBBetter

Cameron & Dillon (2011)It is hypothesized that there is a greater deficit on the LiSN & Learn at the commencement of training (i.e. a greater improvement over time compared with the LiSN-S) because performing the LiSN & Learn requires a greater cognitive load than the LiSN-S (i.e. visual recognition, memory) and these abilities stabilize over time. This difference in performance (compared to normally hearing controls) between the LiSN & Learn and LiSN-S is similar to that seen between the LiSN-CD and LiSN-S.41Randomized Control TrialEarobicsLisn & LearnN = 5N = 5

Cameron, Glyde & Dillon (2012)Future researchCentral processing disorders in elderly peopleBlue Mountains Study: Golding et al (2004)Studied 1576 people > 55 yearsBattery of 7 tests76% failed 1 or more tests64% failed 2 or more tests

But can we give training to overcome it?Chart1-0.46-0.65-0.63-0.83

No hearing lossHearing loss

Sheet1No hearing lossHearing loss3MS-0.46-0.65DSS-0.63-0.83To resize chart data range, drag lower right corner of range.

Chart1-0.46-0.65-0.77-0.62-0.63-0.83-0.98-0.82

No hearing lossHearing lossNo hearing aidsHearing aids

Sheet1No hearing lossHearing lossNo hearing aidsHearing aids3MS-0.46-0.65-0.77-0.62DSS-0.63-0.83-0.98-0.82To resize chart data range, drag lower right corner of range.

Chart40.01411922980.02020065860.03860406210.05761586650.0139371360.02100173380.04201892060.05923322230.0135665530.0214516730.05016205940.06394021610.01273757720.02147394770.05714547850.08442972560.0120417250.02024587510.05850938570.1073993297

15-4950-5960-6970 & overYearPercentage of populationProportion of population with >=25 dB 4FAHL

ABS Pop and SA HL data ABS Projectected population, Australia Series B ('000)Persons200320062011202120310-41264.21232.61202.71228.91235.85-91338.11320.61271.71241.21281.610-141378.91390.91361.11282.6130915-191374.11398.21436.61358.41328.220-241378.91431.41453.71463.11385.325-291364.61387.31490.91552.1147530-3415201475.21445.115711580.935-391461.81516.81523.41596.71657.840-441531.115231547.61525.21650.445-491399.71488.61531.61564.11637.650-541310.513561485.71555.81535.855-591154.61289.613471522.81558.960-64869.9992.61271.31463.11538.265-69719.9793.7964.11301.7148070-74629.3633.1745.511771370.875-79537.6556.5562.7828.61139.580-84368.2411450.1559.9910.185 & over289.8336.1433.2576.2840.6All Ages1989120533.221524.223368.424915.5South Australian DataPrevalence (%) of Hearing Impairment in the better ear averaged over 0.5, 1, 2, 4kHzAge Group25 dBHL45 dBHL65dBHL15-50 years2.80.10.151-6016.320.461-7048.32.50.771+62.821.43.3Overall16.62.80.5

HL projection tablesTable 1Table 2ABS Population numbers ('000) by age in years from 2003 to 20311Prevalence (%) of Hearing Impairment in the Australian population as measured in the better ear averaged over 0.5, 1, 2, 4kHz2Year20032006201120212031PersonsAge Group25 dBHL45 dBHL65dBHL15-4910,03010,22110,42910,63110,71515-50 years2.80.10.150-592,4652,6462,8333,0793,09551-6016.320.460-691,5901,7862,2352,7653,01861-7048.32.50.770 & over1,8251,9372,1923,1424,26171+62.821.43.3All Ages*15,91016,58917,68919,61621,089Overall16.62.80.5Total pop19,89120,53321,52423,36824,916* 15 years & olderTable 3aTable 3bNumber of people ('000) in population with 25dB hearing loss in the better ear by yearPersons with 25dB hearing loss in the better ear expressed as a percentage of the projected total Australian populationPersonsYear20032006201120212031Persons2003200620112021203115-4928128629229830015-491.4%1.4%1.4%1.3%1.2%50-5940243146250250450-592.0%2.1%2.1%2.1%2.0%60-697688631,0801,3351,45860-693.9%4.2%5.0%5.7%5.9%70 & over1,1461,2161,3761,9732,67670 & over5.8%5.9%6.4%8.4%10.7%All Ages*2,5972,7963,2104,1084,938All Ages*13.1%13.6%14.9%17.6%19.8%* 15 years & older* 15 years & olderTable 4aTable 4bNumber of people ('000) in population with 45dB hearing loss in the better ear by yearPersons with 45dB hearing loss in the better ear expressed as a percentage of the projected total Australian populationYear2003200620112021203120032006201120212031PersonsPersons15-49101010111115-490.05%0.05%0.05%0.05%0.04%50-59495357626250-590.25%0.26%0.26%0.26%0.25%60-69404556697560-690.20%0.22%0.26%0.30%0.30%70 & over39141446967291270 & over1.96%2.02%2.18%2.88%3.66%All Ages*4905225928141,060All Ages*2.46%2.54%2.75%3.48%4.25%* 15 years & older* 15 years & olderTable 5aTable 5bNumber of people ('000) in population with 65dB hearing loss in the better ear by yearPersons with 65dB hearing loss in the better ear expressed as a percentage of the projected total Australian populationYear20032006201120212031Persons20032006201120212031Persons15-49101010111115-490.05%0.05%0.05%0.05%0.04%50-59101111121250-590.05%0.05%0.05%0.05%0.05%60-69111316192160-690.06%0.06%0.07%0.08%0.08%70 & over60647210414170 & over0.30%0.31%0.34%0.44%0.56%All Ages*9197110146185All Ages*0.46%0.47%0.51%0.62%0.74%* 15 years & older* 15 years & older1 Trewin D ABS. Population Projections, Australia 2002 to 2101. (ABS catalogue No. 3222.0). 2003. Canberra, Australian Bureau of Statistics.2 Wilson D, Walsh PG, Sanchez L. & Read P. Hearing impairment in an Australian population. 1-54.1998. Centre for Population Studies in Epidemiology, South Australian Department of Human Services.

HL projection tables00000000000000000000

15-4950-5960-6970 & overYearPeople (,000s)Number of people with >=25 dB 4FAHL

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15-4950-5960-6970 & overYearPercentage of populationProportion of population with 4FAHL >=25 dB