The human immunodeficiency virus (HIV) and acquired immune deficiency
syndrome (AIDS) is a worldwide pandemic that affects the lives of millions of people
across all ages. Its devastating effects are far-reaching and affect all aspects of an
individual’s daily life. HIV/AIDS is responsible for widespread clinical manifestations
involving the head and neck. Disorders of the auditory and vestibular systems are
often associated with HIV/AIDS, however the extent and nature of these vestibular
manifestations is still largely unknown.
The main aim of this research study was to investigate vestibular functioning
and pathology in adults with HIV/AIDS. This was achieved through three main
research steps: a systematic literature review of the body of peer-reviewed literature
on HIV/AIDS related vestibular manifestations and pathology, a description and
comparison of vestibular involvement in adults with and without HIV/AIDS and an
investigation to determine if HIV/AIDS influence the vestibulocollic reflex (VCR)
pathways.
For the first study a systematic literature review related to vestibular findings in
individuals with HIV infection and AIDS was conducted. A varied search strategy
was used across several electronic databases to identify relevant peer-reviewed
reports in English. Several databases (Medline, Scopus and PubMed) and search
strategies were employed. Where abstracts were not available, the full paper was
reviewed, and excluded if not directly relevant to the study’s aims. Articles were
reviewed for any HIV/AIDS associated vestibular symptoms and pathologies
reported.
For the second and third study, a cross-sectional, quasi-experimental
comparative research design was employed. A convenience sampling method was
used to recruit subjects. The sample consisted of 53 adults (29 male, 24 female,
aged 23-49 years, mean = 38.5, SD = 4.4) infected with HIV, compared to a control group of 38 HIV negative adults (18 male, 20 female, aged 20-49 years, mean =
36.9, SD = 8.2). A structured interview probed the subjective perception of vestibular
complaints and symptoms. Medical records were reviewed for cluster of
differentiation 4+ (CD4+) cell counts and the use of antiretroviral (ARV) medication.
An otologic assessment and a comprehensive vestibular assessment (bedside
assessments, vestibular evoked myogenic potentials, ocular motor and positional
tests and bithermal caloric irrigation) were conducted on all subjects.
The systematic literature review identified 442 records, reduced to 210 after
excluding duplicates, reviews, editorials, notes, letters and short surveys. These were
reviewed for relevance to the scope of the study. There were only 13 reports
investigating vestibular functioning and pathology in individuals affected by
HIV/AIDS. This condition can affect both the peripheral and central vestibular system,
irrespective of age and viral disease stage. Post-mortem studies suggest direct
involvement of the entire vestibular system, while opportunistic infections such as
oto- and neurosyphilis and encephalitis cause secondary vestibular dysfunction
resulting in vertigo, dizziness and imbalance.
The second study showed an overall vestibular involvement in 79.2% of
subjects with HIV in all categories of disease progression, compared to 18.4% in
those without HIV. Vestibular involvement increased from 18.9% in the Centers for
Disease Control and Prevention (CDC) category 1 to 30.2% in category 2. Vestibular
involvement was 30.1% in category 3. There was vestibular involvement in 35.9% of
symptomatic HIV positive subjects and 41.5% in asymptomatic HIV positive subjects.
Individuals with HIV were 16.6 times more likely to develop vestibular involvement
during their lifetime, than among individuals without this disease. Vestibular
involvement may occur despite being asymptomatic.
The third study showed that abnormal cervical vestibular evoked myogenic
potentials and caloric results were significantly higher in the HIV positive group
(p=.001), with an odds ratio of 10.2. Vestibulocollic reflex and vestibulo-ocular reflex
involvement increased with progression of the disease. There were more abnormal
test results in subjects using ARV therapies (66.7%) compared to those not using
ARV therapies (63.6%), but this difference was not statistically significant. Vestibular involvement was significantly more common in subjects with HIV
than among those without this disease. This disease and its associated risk profile
include direct effects of the virus on the vestibular system as demonstrated by postmortem
studies. Opportunistic infections may compromise the functioning of the
sensory and neural structures of hearing and the vestibular system indirectly, causing
vertigo, dizziness or disequilibrium. Ototoxicity may also be related to vestibular
dysfunction, due to the ototoxic nature of certain ARV medications. HIV/AIDS
influence not only the vestibulo-ocular reflex, but also the vestibulocollic reflex
pathways. Primary health care providers could screen HIV positive patients to
ascertain if there are symptoms of vestibular involvement. If there are any, then they
may consider further vestibular assessments and subsequent vestibular rehabilitation
therapy, to minimize functional limitations of quality of life. / Thesis (DPhil)--University of Pretoria, 2014. / lk2014 / Speech-Language Pathology and Audiology / DPhil / Unrestricted
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:up/oai:repository.up.ac.za:2263/43350 |
| Date | January 2014 |
| Creators | Heinze, Barbara M. |
| Contributors | Swanepoel, De Wet, barbara.heinze@up.ac.za, Vinck, Bart M. |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Rights | © 2014 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. |
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