Nonverbal Neurocognitive Assessment during the Coronavirus Disease of 2019 Pandemic: the Effect of Personal Protective Equipment.

OBJECTIVE: The coronavirus disease of 2019 pandemic has increased personal protective equipment (PPE) use in medical settings. The current study examined the effect of PPE on a nonverbal measure of neurocognitive functioning. METHODS: The Leiter International Performance Scale, Third Edition (Leiter-3) was administered to 125 children between the ages of three and eight. Fifty-nine children were assessed twice without any PPE and 66 were assessed once without and once with PPE. Group differences on composite scores were evaluated using a repeated measures design, accounting for sex, school attendance, socioeconomic status, and HIV status. RESULTS: Nonverbal IQ scores increased significantly between test administrations for both groups, but no significant interaction between PPE group and scores on Leiter-3 composites was found. CONCLUSIONS: No main effect of PPE on Leiter-3 outcomes was found. These results suggest clinical and research work using a nonverbal neurocognitive assessment can be completed when PPE is required.

Peripheral Auditory Function in Young HIV-Positive Adults With Clinically Normal Hearing.

OBJECTIVE: Little is known about peripheral auditory function in young adults with HIV, who might be expected to show early evidence of hearing loss if HIV infection or treatment does affect peripheral function. The goal of this study was to compare peripheral auditory function in 2 age- and gender-matched groups of young adults with clinically normal hearing with and without HIV. STUDY DESIGN: Matched cohort study with repeated measures. SETTING: Infectious disease center in Dar es Salaam, Tanzania. METHODS: Participants included HIV-positive (n = 38) and HIV-negative (n = 38) adults aged 20 to 30 years who had clinically normal hearing, defined as type A tympanograms, air conduction thresholds ≤25 dB HL bilaterally from 0.5 to 8 kHz, and distortion product otoacoustic emissions (DPOAEs) >6 dB above the noise floor bilaterally from 1.5 to 8 kHz. Participants were tested multiple times over 6-month intervals (average, 2.7 sessions/participant) for a total of 208 observations. Primary outcome measures included tympanograms, air conduction audiograms, DPOAEs, and click-evoked auditory brainstem responses. RESULTS: HIV groups did not significantly differ in age, static immittance, or air conduction thresholds. HIV-positive status was independently associated with approximately 3.7-dB lower DPOAE amplitudes from 2 to 8 kHz (95% CI, 1.01-6.82) in both ears and 0.04-µV lower (95% CI, 0.003-0.076) auditory brainstem response wave I amplitudes in the right ear. CONCLUSION: Young adults living with HIV have slightly but reliably smaller DPOAEs and auditory brainstem response wave I amplitudes than matched HIV-negative controls. The magnitude of these differences is small, but these results support measuring peripheral auditory function in HIV-positive individuals as they age.

Nonverbal cognitive assessment of children in Tanzania with and without HIV.

Children living with HIV can experience cognitive difficulties. Most neuropsychological tests have been constructed in Western languages, meaning they may not be appropriate for use in non-Western settings. To address this, we used an entirely nonverbal measure of cognitive ability in a sub-Saharan African sample. For this cross-sectional analysis, 316 children (162 HIV+ and 154 HIV-, ages 3-9) completed the Leiter-3 as part of a larger study in Dar es Salaam, Tanzania. Statistical tests included analysis of covariance and multiple linear regression to account for environmental variables. HIV+ children performed worse than HIV - controls on two composite scores: Nonverbal IQ (p < .001) and Processing Speed (p < 0.001). Similar trends were observed on core subtests. Multiple linear regression models revealed that age, socioeconomic status, and school attendance predicted all Leiter-3 test composites. Critically, the addition of HIV status to the models improved prediction of Nonverbal IQ (∆R2 = 0.03, p = .001) and Processing Speed (∆R2 = 0.06, p < .001). Children living with HIV performed worse than HIV- controls on most Leiter-3 measures. While age, SES, and school attendance predicted Leiter-3 performance, HIV status improved prediction capabilities when added to the model. The Leiter-3 may offer a viable measure of cognitive ability in non-Western settings that can be used in its original form without translation.

The Relationship Between Central Auditory Tests and Neurocognitive Domains in Adults Living With HIV.

Objective: Tests requiring central auditory processing, such as speech perception-in-noise, are simple, time efficient, and correlate with cognitive processing. These tests may be useful for tracking brain function. Doing this effectively requires information on which tests correlate with overall cognitive function and specific cognitive domains. This study evaluated the relationship between selected central auditory focused tests and cognitive domains in a cohort of normal hearing adults living with HIV and HIV- controls. The long-term aim is determining the relationships between auditory processing and neurocognitive domains and applying this to analyzing cognitive function in HIV and other neurocognitive disorders longitudinally. Method: Subjects were recruited from an ongoing study in Dar es Salaam, Tanzania. Central auditory measures included the Gap Detection Test (Gap), Hearing in Noise Test (HINT), and Triple Digit Test (TDT). Cognitive measures included variables from the Test of Variables of Attention (TOVA), Cogstate neurocognitive battery, and Kiswahili Montreal Cognitive Assessment (MoCA). The measures represented three cognitive domains: processing speed, learning, and working memory. Bootstrap resampling was used to calculate the mean and standard deviation of the proportion of variance explained by the individual central auditory tests for each cognitive measure. The association of cognitive measures with central auditory variables taking HIV status and age into account was determined using regression models. Results: Hearing in Noise Tests and TDT were significantly associated with Cogstate learning and working memory tests. Gap was not significantly associated with any cognitive measure with age in the model. TDT explained the largest mean proportion of variance and had the strongest relationship to the MoCA and Cogstate tasks. With age in the model, HIV status did not affect the relationship between central auditory tests and cognitive measures. Age was strongly associated with multiple cognitive tests. Conclusion: Central auditory tests were associated with measures of learning and working memory. Compared to the other central auditory tests, TDT was most strongly related to cognitive function. These findings expand on the association between auditory processing and cognitive domains seen in other studies and support evaluating these tests for tracking brain health in HIV and other neurocognitive disorders.

Unexplained multi-sensory neuropathy syndrome in young Tanzanian adults.

BACKGROUND: A unique syndrome affecting young adults of unexplained hearing loss often associated with uncorrectable poor visual acuity and lower extremity numbness is endemic in Dar es Salaam. This study characterized the hearing loss, associated it with other symptoms, and gathered information on potential causes. METHODS: Forty-seven patients (23 men, 24 women) <40 years old with a symptom consistent with the syndrome, negative syphilis test, and no head injury history were recruited from Muhimbili National Hospital. 18 controls (10 men, 8 women) were recruited from the same neighborhoods as patients. Hearing ability and cochlear outer hair cell function (distortion-product otoacoustic emissions (DPOAEs)) were assessed, as were visual acuity and color vision. Peripheral neuropathy was evaluated using the Michigan Neuropathy Screening Instrument (MNSI), and physical examination. Blood C-reactive protein levels and toenail trace metal concentrations were measured. Environmental exposures were elicited using a questionnaire. Patients with at least two of the following signs were defined as having the syndrome: poor hearing with normal DPOAEs, vision not correctable to better than 20/30, or a MNSI score greater than 4. RESULTS: 29 participants met the case definition. CRP levels did not differ between groups but manganese, cobalt and tin levels were each greater in the cases than controls. No other environmental exposure differences were noted. CONCLUSIONS: Toenail manganese, cobalt, and tin levels were higher in those with the syndrome. These metals are potential neurotoxins suggesting a possible environmental origin for this unique and debilitating syndrome.

Central Auditory Tests to Track Cognitive Function in People With HIV: Longitudinal Cohort Study.

BACKGROUND: The development of neurocognitive deficits in people infected with HIV is a significant public health problem. Previous cross-sectional studies have shown that performance on central auditory tests (CATs) correlates with cognitive test results in those with HIV, but no longitudinal data exist for confirmation. We have been performing longitudinal assessments of central auditory and cognitive function on a cohort of HIV-positive and HIV-negative individuals in Dar es Salaam, Tanzania to understand how the central auditory system could be used to study and track the progress of central nervous system dysfunction. OBJECTIVE: The goal of the project was to determine if CATs can track the trajectory of cognitive function over time in people diagnosed with HIV. METHODS: Tests of peripheral and central auditory function as well as cognitive performance were performed on 382 individuals over the course of 3.5 years. Visits were scheduled every 6 months. CATs included tests of auditory temporal processing (gap detection) and speech perception in noise (Hearing in Noise Test and Triple Digit Test). Cognitive tests included the Montreal Cognitive Assessment (MoCA), Test of Variables of Attention (TOVA), and subtests from the Cogstate battery. HIV-positive subjects were divided into groups based on their CAT results at their final visit (bottom 20%, top 20%, middle 60%). Primary analyses focused on the comparison between HIV-positive individuals that performed worse on CATs (bottom 20%) and the overall HIV-positive group (middle 60%). Data were analyzed using linear mixed-effect models with time as the main fixed effect. RESULTS: The group with the worst (bottom 20%) CAT performance showed a difference in trajectory for the MoCA (P=.003), TOVA (P<.048), and Cogstate (P<.046) over the course of the study period compared to the overall HIV-positive group. A battery of three CATs showed a significant difference in cognitive trajectory over a relatively short study period of 3.5 years independent of age (bottom 20% vs HIV-positive group). CONCLUSIONS: The results of this study support the ability for CATs to track cognitive function over time, suggesting that central auditory processing can provide a window into central nervous system performance. CATs can be simple to perform, and are relatively insensitive to education and socioeconomic status because they only require repeating sentences, numbers, or detecting gaps in noise. These tests could potentially provide a time-efficient, low-cost method to screen for and monitor cognitive decline in patients with HIV, making them a useful surveillance tool for this major public health problem.

Laryngopharyngeal reflux disease, prevalence and clinical characteristics in ENT department of a tertiary hospital Tanzania.

BACKGROUND: Laryngopharyngeal reflux disease (LPRD) is a condition with nonspecific symptoms and most of times patients present late with advanced disease which may predispose to malignancy. The magnitude and clinical characteristics of this condition are not well known among patients attending Otorhinolaryngology services in Tanzania. MATERIALS AND METHODS: This was a hospital based descriptive cross sectional study, conducted in the wards and clinics of Otorhinolaryngology department of Muhimbili National Hospital. Patients with symptoms of Laryngopharyngeal reflux disease were included in the study. Data was collected using questionnaires and clinical examination forms, were processed and analysed by using SPSS. Results presented in frequency tables, cross tabulations and figures. RESULTS: This study recruited 256 participants among them males were 131(51.2%).The mean age was (41.38 ± 13.94) years. Prevalence of Laryngopharyngeal reflux disease was 18.4% without gender predilection. The commonest symptoms were globus sensation, hoarseness of voice and excessive urge to clear the throat with 95.7%, 88.1% and 83.0% respectively while the most observed signs were thick endolaryngeal mucus, Vocal cord oedema and partial ventricular obliteration with 90.9%, 88.6% and 72.7% respectively. Lying down less than two hours after meal and spices foods consumption were the leading risk factors. Hypertension and Diabetes Mellitus type 2 were the most prevalent co morbid conditions associated with Laryngopharyngeal reflux disease. CONCLUSION: The prevalence of Laryngopharyngeal reflux disease is high among patients attending Otorhinolaryngology services at Muhimbili national hospital. All patients with Laryngopharyngeal reflux disease related symptoms should get thorough evaluation for early diagnosis and treatment.

Auditory neurophysiology reveals central nervous system dysfunction in HIV-infected individuals.

OBJECTIVE: To test the hypothesis that human immunodeficiency virus (HIV) affects auditory-neurophysiological functions. METHODS: A convenience sample of 68 HIV+ and 59 HIV- normal-hearing adults was selected from a study set in Dar es Salaam, Tanzania. The speech-evoked frequency-following response (FFR), an objective measure of auditory function, was collected. Outcome measures were FFRs to the fundamental frequency (F0) and to harmonics corresponding to the first formant (F1), two behaviorally relevant cues for understanding speech. RESULTS: The HIV+ group had weaker responses to the F1 than the HIV- group; this effect generalized across multiple stimuli (d = 0.59). Responses to the F0 were similar between groups. CONCLUSIONS: Auditory-neurophysiological responses differ between HIV+ and HIV- adults despite normal hearing thresholds. SIGNIFICANCE: The FFR may reflect HIV-associated central nervous system dysfunction that manifests as disrupted auditory processing of speech harmonics corresponding to the first formant.

Hearing complaints in HIV infection originate in the brain not the ear.

OBJECTIVE: Evidence suggests damage to brain auditory pathways, rather than inner ear damage, underlies the hearing difficulties HIV+ individuals report. But, antiretroviral therapy (ART) may affect the hearing system and also lead to hearing complaints. DESIGN: Longitudinal study of HIV+ and HIV- individuals in Dar es Salaam Tanzania. A subset of this cohort started ART while in the study allowing the effects of ART to be studied directly. METHODS: The ability to hear quiet sounds (pure-tone audiometry), cochlear outer hair cell function [distortion-product otoacoustic emissions (DPOAEs)], and gaps-in-noise detection thresholds (a central auditory processing test) were assessed at each visit. Visits were scheduled for 6-month intervals, but the number and spacing of visits varied. In the group that started ART while in the study, 107 HIV+ individuals had audiometric thresholds, 98 had DPOAEs, and 98 had gap measurements suitable for analysis. Data were analyzed using a linear mixed model with time and starting ART as fixed effects and individual participant repeated measures as random effects. RESULTS: Starting ART did not affect audiometric or gap detection thresholds. The slope of the DPOAE amplitude vs. time relationship was more negative after starting ART but did not differ from the HIV- group. Gap thresholds were higher in the HIV+ group. CONCLUSION: ART did not affect audiometric thresholds significantly suggesting common ART drugs are not major ototoxins. The gap detection results from the study show effects on central auditory processing in HIV+ individuals, supporting the origin of HIV-related hearing complaints in the central auditory system.

Auditory Impairments in HIV-Infected Children.

OBJECTIVES: In a cross-sectional study of human immunodeficiency virus (HIV)-infected adults, the authors showed lower distortion product otoacoustic emissions (DPOAEs) in HIV+ individuals compared with controls as well as findings consistent with a central auditory processing deficit in HIV+ adults on antiretroviral therapy. The authors hypothesized that HIV+ children would also have a higher prevalence of abnormal central and peripheral hearing test results compared with HIV- controls. DESIGN: Pure-tone thresholds, DPOAEs, and tympanometry were performed on 244 subjects (131 HIV+ and 113 HIV- subjects). Thirty-five of the HIV+, and 3 of the HIV- subjects had a history of tuberculosis treatment. Gap detection results were available for 18 HIV- and 44 HIV+ children. Auditory brainstem response results were available for 72 HIV- and 72 HIV+ children. Data from ears with abnormal tympanograms were excluded. RESULTS: HIV+ subjects were significantly more likely to have abnormal tympanograms, histories of ear drainage, tuberculosis, or dizziness. All audiometric results were compared between groups using a two-way ANOVA with HIV status and ear drainage history as grouping variables. Mean audiometric thresholds, gap detection thresholds, and auditory brainstem response latencies did not differ between groups, although the HIV+ group had a higher proportion of individuals with a hearing loss >25 dB HL in the better ear. The HIV+ group had reduced DPOAE levels (p < 0.05) at multiple frequencies compared with HIV- subjects. No relationships were found between treatment regimens or delay in starting treatment and audiological parameters. CONCLUSIONS: As expected, children with HIV+ were more likely to have a history of ear drainage, and to have abnormal tympanograms. Similar to the adult findings, the HIV+ group did not show significantly reduced audiometric thresholds, but did have significantly lower DPOAE magnitudes. These data suggest that (1) HIV+ children often have middle ear damage which complicates understanding the direct effects of HIV on the hearing system, and (2) even when corrected for confounders DPOAEs were lower in the HIV+ group. Previous studies suggest ototoxicity from antiretroviral drugs is an unlikely cause of the reduced DPOAE magnitudes. Other possibilities include effects on efferent pathways connecting to outer hair cells or a direct effect of HIV on the cochlea.

Auditory impairments in HIV-infected individuals in Tanzania.

OBJECTIVES: Abnormal hearing tests have been noted in human immunodeficiency virus (HIV)-infected patients in several studies, but the nature of the hearing deficit has not been clearly defined. The authors performed a cross-sectional study of both HIV+ and HIV- individuals in Tanzania by using an audiological test battery. The authors hypothesized that HIV+ adults would have a higher prevalence of abnormal central and peripheral hearing test results compared with HIV- controls. In addition, they anticipated that the prevalence of abnormal hearing assessments would increase with antiretroviral therapy (ART) use and treatment for tuberculosis (TB). DESIGN: Pure-tone thresholds, distortion product otoacoustic emissions (DPOAEs), tympanometry, and a gap-detection test were performed using a laptop-based hearing testing system on 751 subjects (100 HIV- in the United States, plus 651 in Dar es Salaam, Tanzania, including 449 HIV+ [130 ART- and 319 ART+], and 202 HIV-, subjects. No U.S. subjects had a history of TB treatment. In Tanzania, 204 of the HIV+ and 23 of the HIV- subjects had a history of TB treatment. Subjects completed a video and audio questionnaire about their hearing, as well as a health history questionnaire. RESULTS: HIV+ subjects had reduced DPOAE levels compared with HIV- subjects, but their hearing thresholds, tympanometry results, and gap-detection thresholds were similar. Within the HIV+ group, those on ART reported significantly greater difficulties understanding speech in noise, and were significantly more likely to report that they had difficulty understanding speech than the ART- group. The ART+ group had a significantly higher mean gap-detection threshold compared with the ART- group. No effects of TB treatment were seen. CONCLUSIONS: The fact that the ART+/ART- groups did not differ in measures of peripheral hearing ability (DPOAEs, thresholds), or middle ear measures (tympanometry), but that the ART+ group had significantly more trouble understanding speech and had higher gap-detection thresholds indicates a central processing deficit. These data suggest that: (1) hearing deficits in HIV+ individuals could be a CNS side effect of HIV infection, (2) certain ART regimens might produce CNS side effects that manifest themselves as hearing difficulties, and/or (3) some ART regimens may treat CNS HIV inadequately, perhaps due to insufficient CNS drug levels, which is reflected as a central hearing deficit. Monitoring of central hearing parameters could be used to track central effects of either HIV or ART.

Pure-tone audiometric threshold assessment with in-ear monitoring of noise levels.

OBJECTIVE: Our objective was to obtain reliable threshold measurements without a sound booth by using a passive noise-attenuating hearing protector combined with in-ear 1/3-octave band noise measurements to verify the ear canal was suitably quiet. DESIGN: We deployed laptop-based hearing testing systems to Tanzania as part of a study of HIV infection and hearing. An in-ear probe containing a microphone was used under the hearing protector for both the in-ear noise measurements and threshold audiometry. The 1/3-octave band noise spectrum from the microphone was displayed on the operator's screen with acceptable levels in grey and unacceptable levels in red. Operators attempted to make all bars grey, but focused on achieving grey bars at 2000 Hz and above. STUDY SAMPLE: 624 adults and 197 children provided 3381 in-ear octave band measurements. Repeated measurements from 144 individuals who returned for testing on three separate occasions were also analysed. RESULTS: In-ear noise levels exceeded the maximum permissible ambient noise levels (MPANL) for ears not covered, but not the dB SPL levels corresponding to 0 dB HL between 2000-4000 Hz. In-ear noise measurements were repeatable over time. CONCLUSIONS: Reliable audiometry can be performed using a passive noise-attenuating hearing protector and in-ear noise measurements.