ehdi in 20102 - mount sinai hospitaldistribution of age at hearing aid fitting for hearing impaired...
TRANSCRIPT
Big Picture
TerminationFragmentationRefinementEvolutionTransformation
Spin-off benefits
Reasons to continue
• Early child development is a priority
• Communication development is a core element of ECD programming
• EHDI (done properly) WORKS!
Distribution of age at hearing aid fitting for hearing impaired newborns before and after NHSP introduced
Age of hearing aid fitting in weeks
0
20
40
60
80
100
0 100 200 300 400 500
Perc
entil
e of
dis
trib
utio
n fo
r aid
ed c
hild
ren
NHSP 2003/4
Before NHSP
(NHSP eSP data Feb 2005, n=228; Davis et al 1997 n=495)
Long-term language benefit
• Kennedy C et al NEJM 2006, 354;20:2131-41
• Early identification improved receptive language at 7-10 years by nearly 1 SD !
• This is virtually definitive evidence
FRAGMENTATION
An insidious threat
EHDI program threats
• Large programs inexorably fragment without strong, sustained centralizing force
• Local practise variability undermines equity, improvement, overall effectiveness
• Local funding control is a major challenge (downloading or initial framework)
IMPROVEMENT
Loss to follow-upScreening inconsistency
Program-level domino effect
• C > S1 > S1S2 > S2 > S2Dx > Dx > DxI > I = O• .958 = .66 .908 = .43
• C > S > SDx > Dx > DxI > I = O.956 = .74 .906 = .53
• C > SDx > DxI > I = O.954 = .81 .904 = .66
Loss to follow-up
• Reduce loss opportunity (steps,intervals)• Strengthen messaging (refer??)• Lock-in follow-up appointments• Synchronize follow-up services• Improve tracking• Enhance physician support• Enhance peer pressure / support
Screening refer rate variation
• Refer rates vary by a factor of 10 !
• ‘Test refer rate’ concept ??? (FPR) !
• Environment, actual procedure, skill
• Train, monitor, feedback, cont ed, share
Variable referral to diagnostics from 32 IHP regions in 2006
0
0.5
1
1.52
2.5
3
3.5
4
100 1000 10000 100000
number screened
Dx a
cces
sed
Emerging truth about screening
• The more you do it, the better you get
• Dedicated staff !, fewer sites ?
• Training (?), protocols, monitoring & feedback, continuing guidance, sharing experiences and solutions
EVOLUTION
The trouble with clicksWhen NOT to screen
Role of ASSRAD diagnosis
The trouble with click AABR
• MUCH better than a handclap, BUT
• Stimulus type• Click does not reflect status < 1 kHz• Click asks the wrong question !
• Stimulus level• What nominal level? What variation?
Can we do better than click AABR?
• Ask the right question…Multi-frequency tonepip AABR
• Multi-frequency ASSR…Simpler automatic scoring. Sensitivity? Optimization? Patent issues?
• 500 Hz problem – no way around it
Who should not be screened?• Screens: make statistical FN errors
do not assess low frequenciesmiss high-frequency lossesmiss frequency-specific lossescan miss mild lossesOAE screens miss AD
• Good diagnostics DO NOT make these errors and omissions
Who should NOT be screened?
• Screens DO NOT detect hearing loss!• They change the PROBABILITY of loss• Create high-risk subset for diagnostics• P(PCHI) given AABR fail ~ 10% (<20%)
• Some risk indicators have a higher PPV than AABR screening failure!
High PPV >>> Dx audiometry
• Congenital CMV infection • Severe neonatal hypoxia• Ear canal agenesis or marked atresia• Severe hyperbilirubinemia• Many syndromes (Pendred, Usher, BOR,
Waardenburg, CHARGE, Goldenhar, etc)• Bacterial meningitis, etc
Role of ASSR in PCHI Dx testing
• ASSR is just ABR V-V’ overlapped• Less skill, easy automatic detection• Better freq-spec remains unproven• Multi-freq efficiency vs nonadaptivity• Sensitivity at low HTLs is a question• Much-quoted utility at high HTLs may be
an artifact of dBnHL definition• Complementarity to tonepip ABR unclear
Auditory Dys-synchrony puzzle
• You only find what you look for…
• There is more of it than we realize
• It is neither all-or-none nor exclusive
• Some of it is very hard to diagnose
Classic CM example in AD
big CM, small wave V
small CM, no ABR
big CM, wave I ? + slow wave
Problematic CM/AEP records in AD/?AD
An uncomfortable truth
• AD does not protect the subject against conductive or sensory (OHC) dysfunction
SO
• The generic problem is to disentangle conductive + OHC +AD components
Threshold: use N1-P2 precursor
• N1-P2 much less dependent on neural synchrony than ABR, MLR
• Use ordinary toneburst eg 10-40-10 ms• Use 10 dB AM tone (Zeng 2005 DL data)
• Measure CHL+SHL components (AC, BC)
Un uncomfortable probability
• AD is not an all-or none phenomenon• There are degrees of AD dysfunction
• ABRs vestigial or dysmorphic & may track down in level
• +ve TABR thresh errors? Poor I-O fns?
AD dysfunction gradation Michalewski H et al Clin Neurophys 2005
0
10
20
30
40
50
60
0 10 20 30 40 50 60 70 80 90 100
puretone average dBHL
gap
thes
hold
ms
Priority investigations
• N1 thresholds in all AD, ?AD, PCHI
• N1 FM thresholds to discriminate AD/SHL • N1 gap thresholds to quantify dysfunction
• CM & CABR I-O fns in all AD,?AD, PCHI• ? SP detection & I-O functions (?IHC)
REVOLUTION
SurveillanceEpidemiology of emergent PCHI
CytomegalovirusMolecular genetics
Prevalence, PHI >40 dBHL ave bilateral
0
0.5
1
1.5
2
2.5
1 2 3 4 5 6 7 8 9 10 11 12
age in years
case
s pe
r tho
usan
d
Fortnum et al BMJ 2001;323:536
Surveillance: who, how, when?
• Very high-risk need serial diagnostics
• High-risk need serial f-spec screening
• Strategy should reflect epidemiology of PCHI expression in relation to risk profile
• Need better epidemiologic models!
Newborn Hearing Screening –A Silent Revolution
Morton C, Nance WNEJM 2006 (May) 354:2151-64
PCHI causes at birth & at 4 yearsprevalence-etiology pies
1.9/1000 2.7/1000
Pendred 3%
OtherSyndromic 14%
CMV 21%
OtherEnvironmental 14%
GJB2 21%
OtherNonsyndromic 30%
CMV 25%
OtherEnvironmen14%
GJB2 15%
OtherNonsyndromic 22%
OtherSyndromic 11%
EVA P+ 7%
EVA P- 5%
mt 1%
tal
cPCHI Etiology
100 PCHI/ \
Genetic 60 Env 40/ \ I
Non-S 45 S 15 cCMV 21/ I \
ar 36 ad 7 x 1 mt 1 (6-18 Spain, E Asia)I
GJB2,6 22
Congenital CMV epidemiccdc.gov.cmv.facts.htm
• 50-80% US adults have CMV by 40 y• 1-4% uninfected mothers develop primary CMV• 33% primaries pass to unborn child• 1:150 born with congenital CMV (cCMV)• 1:750 develop permanent disability 0-5y
– Hearing, vision, mental, lung, liver, spleen etc..• Only 10% cCMV newborns symptomatic at birth
CMV Treatment & Prevention
• Antivirals (ganciclovir) in severe cCMV• Screening: Europe - yes, North Am - no• Dx, Px (eg neonatal blood CMV genomes)
• US NAS IOM: CMV vaccine ‘first priority’• Many methods in Phase I-III trials, several
agents FDA-approved for transplants
Molecular genetics 2012
• Will be able to screen for causes of majority of genetic PCHI
• Map entire individual genome for < $100 ?!
• Will transform etiologic Dx strategy (retro)• May transform surveillance strategy (pro)
Spin-off advances
• Restructuring pediatric audiology services
• Evidence-based revolution in intervention
• Sudden Infant Death risk prediction ! ?• Rubens 07: case-control (31 SIDS, 31 N)
TEOAE SNR L>R SIDS, R>L Normals• Vestibular hair-cells signal O2 tension ?