Fu-Shing Lee

Longitudinal study of pure-tone thresholds in older persons.

Objective: Pure-tone thresholds for conventional and extended high frequencies were analyzed for 188 older adult human subjects (91 females, 97 males). The objectives were to study longitudinal changes in thresholds as well as the effects of initial threshold levels, age, gender, and noise history on these longitudinal changes. Design: At the time of entry into the study, subjects’ ages ranged from 60 to 81 years, with a mean age of 68 years. Subjects had between 2 and 21 visits (mean = 9.81 visits) over a period of 3 to 11.5 years (mean = 6.40 years). Conventional pure-tone thresholds at 0.25 to 8 kHz were measured during most visits. Extended high-frequency (EHF) thresholds at 9 to 18 kHz were measured every 2 to 3 years. The slope of a linear regression was used to estimate the rate of change in pure-tone thresholds at 0.25 to 18 kHz for each ear. A questionnaire was used to identify those subjects with a positive noise history. Results: The average rate of change in thresholds was 0.7 dB per year at 0.25 kHz, increasing gradually to 1.2 dB per year at 8 kHz and 1.23 dB per year at 12 kHz. The rate of change for thresholds increased significantly with age, at 0.25 to 3, 10, and 11 kHz for females and at 6 kHz for males. After adjusting for age, females had a significantly slower rate of change at 1 kHz but a significantly faster rate of change at 6 to 12 kHz than males. For 0.25 and 1 kHz, subjects with more hearing loss at higher frequencies had a faster rate of change at these frequencies, whereas for 6 and 8 kHz, subjects with more hearing loss at mid and high frequencies had a slower rate of change at these frequencies. The rates of threshold change for subjects with a positive noise history were not statistically different from those with a negative noise history. Conclusions: On average, hearing threshold increased approximately 1 dB per year for subjects age 60 and over. Age, gender, and initial threshold levels can affect the rate of change in thresholds. Older female subjects (≥70 years) had faster rate of change at 0.25 to 3, 10, and 11 kHz than younger female subjects (60 to 69 years). Older male subjects had faster rate of change at 6 kHz than younger male subjects. Females had a slower rate of change at 1 kHz and a faster rate of change at 6 to 12 kHz than males. Subjects with higher initial thresholds at low and mid frequencies tended to have faster rate of threshold change at 0.25 to 2 kHz in the following years. Subjects with higher initial thresholds at mid and higher frequencies tended to have slower rate of change at 6 to 8 kHz in the following years. Noise history did not have a significant effect on the rate of threshold changes.

Incidence of Skull Base and Orbital Erosion in Allergic Fungal Rhinosinusitis (AFRS) and Non-AFRS

OBJECTIVE: To compare the incidence of bony erosion associated with allergic fungal rhinosinusitis (AFRS) with the incidence of bony erosion seen in other types of inflammatory sinusitis. STUDY DESIGN: Retrospective review. RESULTS: AFRS was diagnosed in 27 patients, and 15/27 (56%) had bony skull base or orbital erosion. Non-AFRS chronic sinusitis required surgery in 158 patients, but only 8 (5%) had bony skull base or orbital erosion (P < 0.01). AFRS patients were 12.6 times (P < 0.01) more likely to have bony erosion than non-AFRS patients. African American males were 15.0 times (P < 0.01) more likely to have bony erosion than whites and African American females combined. CONCLUSION: Bony erosion with intracranial and intraorbital extension is much more common in AFRS than all other types of inflammatory sinusitis combined. African American males have a higher incidence of AFRS, as well as intracranial and intraorbital extension.

Classifying Human Audiometric Phenotypes of Age-Related Hearing Loss from Animal Models

Age-related hearing loss (presbyacusis) has a complex etiology. Results from animal models detailing the effects of specific cochlear injuries on audiometric profiles may be used to understand the mechanisms underlying hearing loss in older humans and predict cochlear pathologies associated with certain audiometric configurations (“audiometric phenotypes”). Patterns of hearing loss associated with cochlear pathology in animal models were used to define schematic boundaries of human audiograms. Pathologies included evidence for metabolic, sensory, and a mixed metabolic + sensory phenotype; an older normal phenotype without threshold elevation was also defined. Audiograms from a large sample of older adults were then searched by a human expert for “exemplars” (best examples) of these phenotypes, without knowledge of the human subject demographic information. Mean thresholds and slopes of higher frequency thresholds of the audiograms assigned to the four phenotypes were consistent with the predefined schematic boundaries and differed significantly from each other. Significant differences in age, gender, and noise exposure history provided external validity for the four phenotypes. Three supervised machine learning classifiers were then used to assess reliability of the exemplar training set to estimate the probability that newly obtained audiograms exhibited one of the four phenotypes. These procedures classified the exemplars with a high degree of accuracy; classifications of the remaining cases were consistent with the exemplars with respect to average thresholds and demographic information. These results suggest that animal models of age-related hearing loss can be used to predict human cochlear pathology by classifying audiograms into phenotypic classifications that reflect probable etiologies for hearing loss in older humans.

Longitudinal changes in speech recognition in older persons

Recognition of isolated monosyllabic words in quiet and recognition of key words in low- and high-context sentences in babble were measured in a large sample of older persons enrolled in a longitudinal study of age-related hearing loss. Repeated measures were obtained yearly or every 2 to 3 years. To control for concurrent changes in pure-tone thresholds and speech levels, speech-recognition scores were adjusted using an importance-weighted speech-audibility metric (AI). Linear-regression slope estimated the rate of change in adjusted speech-recognition scores. Recognition of words in quiet declined significantly faster with age than predicted by declines in speech audibility. As subjects aged, observed scores deviated increasingly from AI-predicted scores, but this effect did not accelerate with age. Rate of decline in word recognition was significantly faster for females than males and for females with high serum progesterone levels, whereas noise history had no effect. Rate of decline did not accelerate with age but increased with degree of hearing loss, suggesting that with more severe injury to the auditory system, impairments to auditory function other than reduced audibility resulted in faster declines in word recognition as subjects aged. Recognition of key words in low- and high-context sentences in babble did not decline significantly with age.

Gender‐Specific Effects of Drugs on Hearing Levels of Older Persons

ABSTRACT: As part of a study of human presbyacusis, a questionnaire on medicinal drug usage was given to 357 subjects (184 females, 173 males). Previous results from 211 subjects showed gender effects, that is, for males, none of the drugs had any measurable effects on hearing, whereas women taking calcium channel blockers (CCBs) had hearing levels 12 dB better than women not taking them; women taking β adrenergic medication had hearing levels 20 dB poorer, and women taking antihistamine/cold preparations had hearing levels 9 dB poorer. Results from the original 211 subjects were confirmed when the sample size was increased from 211 to 357 subjects only for the β adrenergic medications. Results for antihistamine/cold preparation medications showed small effects only for female subjects. Data from 13 additional female subjects who used CCBs showed hearing levels 10–14 dB poorer than predicted from the original data. Male data were consistent in both samples. The inconsistency for females could reflect sampling error. A more likely possibility is that since the original 10 subjects using CCBs had a mean age of 72 yr and the second sample of 13 had a mean age of 79.5 yr, poorer hearing levels might be anticipated because of the difference in chronological age and possibly duration of drug usage.

Randomized Controlled Trial of Hyaluronic Acid/Carboxymethylcellulose Dressing after Endoscopic Sinus Surgery

Objective: To determine if a hyaluronic acid/carboxymethylcellulose (HA/CMC) sinus dressing reduces the rate of postoperative scarring. Methods: In a randomized, matched-controlled, single-blinded study, following the completion of surgery, an HA/CMC dressing was randomly assigned to one side with the opposite unpacked side serving as a control. Results: Fifty-three patients underwent surgery for chronic rhinosinusitis (CRS; 39 patients) or CRS with nasal polyposis (14 patients). At the 8-week follow-up, there was no difference in synechiae on the HA/CMC side compared to the control (p = 0.09). HA/CMC-treated sinuses, however, demonstrated fewer synechiae in the first 2 weeks postoperatively compared to the control (p = 0.01), and were associated with significantly less nasal congestion at the 4-week (p = 0.02) and 8-week follow-up visits (0.03). Conclusion: There was no long-term difference in the rate of synechiae in the HA/CMC-treated sinus compared to the control. However, less severe nasal congestion and synechiae in the initial postoperative period may reduce the need for aggressive sinus debridement.