Transcript Poster - Northern Arizona University

Risk Factors for a High-Frequency Hearing Loss in US Youth: Data from the NHANES (2005-2010)
Ishan Bhatt, PhD, CCC-A , O’neil Guthrie, PhD, CCC-A, Michael Skelton, AuD, CCC-A
Communication Sciences and Disorders, Northern Arizona University
BACKGROUND
 Presbycusis is a complex disorder which is caused by multiple genes
in combination with lifestyle and environmental factors. Genetic risk
profiling is a promising strategy to prevent presbycusis (Ciobra et al,
2015).
 A recent study in college-aged musicians identified high-frequency
hearing loss (HFHL) as an audiometric configuration (Phillips et al.,
2015) which may be treated as a presbycusis phenotype.
AIMES OF THE STUDY
1. To study the prevalence of HFHL in US youth (12-19 years) using the
National Health And Nutrition Examination Survey (NHANES 20052010) database.
2. To evaluate the effect of non-genetic risk factors (i.e. gender, age,
ethnicity, family income, work-related noise exposure, recreational
noise exposure, acoustic exposure just before testing, firearm noise
exposure, tinnitus and ear canal volume) on the bilateral HFHL.
METHODS
 Audiometric testing was performed by NHANES (2005-10).
 Data was collected through household interviews followed by a
standardized physical examination. Demographic and audiometric
databases from NHANES 2005-06, 07-08 and 09-10 were merged.
 Individuals ranging in age from 12-19 years with bilateral normal
otoscopic findings, compliance value ranging from 0.2 to 1.8 cc, and
middle ear pressure ranging from -100 to 50 dapa in both ears were
considered for the further analysis. (Total: 3595 participants)
Audiometric Measures
 Interacoustic model AD226 audiometer with standard TDH-39
headphones were used to measure hearing sensitivity. Testing was
conducted using modified Hughson Westlake procedure.
Definition of High-Frequency Hearing Loss (HFHL) Configuration
 A drop in hearing sensitivity at 8 kHz of at least 15 dB from the selfreferenced previous best threshold in a linear progression of
frequencies, and minimally a 15 dB HL threshold was considered a
High-Frequency Hearing Loss configuration (Phillips et al., 2015)
Demographic and Survey data
 Sex of the participants was categorized as male and female
 Tinnitus was considered present if a participant answered positive to: In the
past twelve months, have you been bothered by ringing, roaring, or buzzing in
your ears or head that lasts for five minutes or more?
RESULTS (continued)
 Socioeconomic status: low (PIR≤1.3), mid (PIR: 1.4-3.5) and high (PIR > 3.5).
 Age of participants was categorized in four subgroups: 12-13 years, 14-15
years, 16-17 years, and 18-19 years.
 Race/ethnicity was re-coded into non-Hispanic European American, nonHispanic African American, Hispanic and other races (including multiracial).
 Firearms noise exposure was considered positive if a participant answered
positively to the question: Have you ever used firearms for target shooting,
hunting, or for any other purposes?
 Work-related noise exposure was defined as positive if a participant answered
positively to the question: Have you ever had a job where you were exposed
to loud noise for five or more hours a week?
Figure 1: HFHL Configuration in the NHANES (2005-2010) database: Mean
thresholds at 1000-8000 Hz for participants with no HFHL (blue line) vs. HFHL
(red line). Error bars: 95% CI
 Music exposure was defined as positive if a participant identified exposure to
loud noise or music for five or more hours per week outside of a job.
 Risk-factors for the HFHL: Multinomial logistic regression analysis with a HFHL
as a dependent variable (with 3 levels: no HFHL, unilateral HFHL, bilateral
HFHL) and with the above listed factors as dependent variables were used to
identify the risk-factors of the HFHL.
 History of smoking was considered positive if a participant answered positively
to any of the following questions: Have you ever tried smoking? or Does
anyone smoke at home?
 The analysis revealed that unilateral HFHL was associated with race and ECV,
where participants with European American ancestry and low/moderate ECV
showed significantly high odds of unilateral HFHL.
 Average ear canal volume (ECV) was calculated from the tympanometric data.
The quartile ranges were considered as low, moderate, moderately-high and
high ECV respectively.
 Bilateral HFHL was associated with race, music exposure and ECV, where
participants with European American ancestry, positive history of music
exposure and low/moderately-high ECV showed significantly high odds of
bilateral HFHL.
RESULTS
DISCUSSION
 Prevalence of bilateral HFHL: 4.3 % (143 participants)
 Major finding of this study is that ECV can predict a HFHL configuration.
 Prevalence of unilateral notches: 19.1% (639 participants)
Associated
Variables
Unilateral HFHL
(Odds Ratio)
Associated
Variables
Bilateral HFHL
(Odds Ratio)
African American <
European American
0.758
(p < 0.05)
Hispanic < European
American
0.588
(p < 0.05)
Hispanic < European
American
0.723
(p < 0.01)
Music Exposure > No
Music Exposure
1.532
(p < 0.05)
Low ECV > High ECV
1.659
(p < 0.001)
Low ECV > High ECV
1.901
(p < 0.05)
Moderate ECV > High
ECV
1.443
(p < 0.01)
Moderately-high ECV
> High ECV
2.391
(p < 0.01)
Tables: Results of the Multinomial Logistic Regression Analysis: Factors
associated with unilateral and bilateral HFHL.
 It can be hypothesized that HFHL is related with variation in sound pressure
level in the ear canal. Standing waves may be a candidate mechanism
underlying a HFHL configuration.
 Another explanation may be derived from Gerhardt et al (1987). The authors
showed that college-aged individuals with low ECV acquired highest temporary
threshold shift (TTS) at higher frequencies (around 6000 Hz) compared to
individuals with high ECV who acquired highest TTS at lower frequencies
following an identical white noise exposure. Young adults aged 12-19 years
may show lower ECV and higher resonance frequency of the ear canal than
college-aged adults. Subsequently, they may acquire HFHL secondary to loud
music exposure.
 Future research will test these hypotheses.