| 1. |
- Berglin, Cecilia Engmer, et al.
(författare)
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Local treatment of the inner ear : A study of three different polymers aimed for middle ear administration
- 2015
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Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 135:10, s. 985-994
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Tidskriftsartikel (refereegranskat)abstract
- Conclusion: A formulation based on sodium hyaluronate (NaHYA) was the most promising candidate vehicle for intra-tympanic drug administration regarding conductive hearing loss, inflammatory reactions, and elimination. Objectives: Recent advances in inner ear research support the idea of using the middle ear cavity for drug administration to target the inner ear. This paper presents rheological and safety assessments of three candidate polymer formulations for intra-tympanic drug administration. Method: The formulations were based on sodium carboxymethyl cellulose (NaCMC), sodium hyaluronate (NaHYA), and poloxamer 407 (POL). Rheological studies were performed with a controlled rate instrument of the couette type. Safety studies were performed in guinea pigs subjected to an intra-tympanic injection of the formulations. Hearing function was explored with ABR before and 1, 2, and 3 weeks after the injection. Elimination of the formulations marked with coal was explored with an endoscopic digital camera 1, 2, and 3 weeks after injection. Middle and inner ear morphology was examined with light microscopy 6 days after injection. Results: The results speak in favor of NaHYA, since it did not cause prolonged hearing threshold elevations. The results of the elimination and morphological investigations support the conclusion of NaHYA being the most promising candidate for intra-tympanic administration.
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| 2. |
- Berglin, Cecilia Engmer, et al.
(författare)
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Prevention of cisplatin-induced hearing loss by administration of a thiosulfate-containing gel to the middle ear in a guinea pig model
- 2011
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Ingår i: Cancer Chemotherapy and Pharmacology. - New York : Springer-Verlag New York. - 0344-5704 .- 1432-0843. ; 68:6, s. 1547-1556
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Tidskriftsartikel (refereegranskat)abstract
- Thiosulfate may reduce cisplatin-induced ototoxicity, most likely by relieving oxidative stress and by forming inactive platinum complexes. This study aimed to determine the concentration and protective effect of thiosulfate in the cochlea after application of a thiosulfate-containing high viscosity formulation of sodium hyaluronan (HYA gel) to the middle ear prior to i.v. injection of cisplatin in a guinea pig model. The release of thiosulfate (0.1 M) from HYA gel (0.5% w/w) was explored in vitro. Thiosulfate in the scala tympani perilymph of the cochlea 1 and 3 h after application of thiosulfate in HYA gel to the middle ear was quantified with HPLC and fluorescence detection. Thiosulfate in blood and CSF was also explored. The potential otoprotective effect was evaluated by hair cell count after treatment with thiosulfate in HYA gel applied to the middle ear 3 h prior to cisplatin injection (8 mg/kg b.w.). HYA did not impede the release of thiosulfate. Middle ear administration of thiosulfate in HYA gel gave high concentrations in the scala tympani perilymph while maintaining low levels in blood, and it protected against cisplatin-induced hair cell loss. HYA gel is an effective vehicle for administration of thiosulfate to the middle ear. Local application of a thiosulfate-containing HYA gel reduces the ototoxicity of cisplatin most likely without compromising its antineoplastic effect. This provides a minimally invasive protective treatment that can easily be repeated if necessary.
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| 3. |
- Fransson, Anette E, et al.
(författare)
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Hydrogen Inhalation Protects against Ototoxicity Induced by Intravenous Cisplatin in the Guinea Pig
- 2017
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Ingår i: Frontiers in Cellular Neuroscience. - : Frontiers Media SA. - 1662-5102. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Permanent hearing loss and tinnitus as side-effects from treatment with the anticancer drug cisplatin is a clinical problem. Ototoxicity may be reduced by co-administration of an otoprotective agent, but the results in humans have so far been modest.Aim: The present preclinical in vivo study aimed to explore the protective efficacy of hydrogen (H2) inhalation on ototoxicity induced by intravenous cisplatin.Materials and Methods: Albino guinea pigs were divided into four groups. The Cispt (n = 11) and Cispt+H2 (n = 11) groups were given intravenous cisplatin (8 mg/kg b.w., injection rate 0.2 ml/min). Immediately after, the Cispt+H2 group also received gaseous H2 (2% in air, 60 min). The H2 group (n = 5) received only H2 and the Control group (n = 7) received neither cisplatin nor H2. Ototoxicity was assessed by measuring frequency specific ABR thresholds before and 96 h after treatment, loss of inner (IHCs) and outer (OHCs) hair cells, and by performing densitometry-based immunohistochemistry analysis of cochlear synaptophysin, organic transporter 2 (OCT2), and copper transporter 1 (CTR1) at 12 and 7 mm from the round window. By utilizing metabolomics analysis of perilymph the change of metabolites in the perilymph was assessed.Results: Cisplatin induced electrophysiological threshold shifts, hair cell loss, and reduced synaptophysin immunoreactivity in the synapse area around the IHCs and OHCs. H2 inhalation mitigated all these effects. Cisplatin also reduced the OCT2 intensity in the inner and outer pillar cells and in the stria vascularis as well as the CTR1 intensity in the synapse area around the IHCs, the Deiters' cells, and the stria vascularis. H2 prevented the majority of these effects.Conclusion: H2 inhalation can reduce cisplatin-induced ototoxicity on functional, cellular, and subcellular levels. It is proposed that synaptopathy may serve as a marker for cisplatin ototoxicity. The effect of H2 on the antineoplastic activity of cisplatin needs to be further explored.
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| 4. |
- Fransson, Anette Elisabeth, et al.
(författare)
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Inhalation of Molecular Hydrogen, a Rescue Treatment for Noise-Induced Hearing Loss
- 2021
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Ingår i: Frontiers in Cellular Neuroscience. - : Frontiers Media S.A.. - 1662-5102. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- Noise exposure is the most important external factor causing acquired hearing loss in humans, and it is strongly associated with the production of reactive oxygen species (ROS) in the cochlea. Several studies reported that the administration of various compounds with antioxidant effects can treat oxidative stress-induced hearing loss. However, traditional systemic drug administration to the human inner ear is problematic and has not been successful in a clinical setting. Thus, there is an urgent need to develop rescue treatment for patients with acute acoustic injuries. Hydrogen gas has antioxidant effects, rapid distribution, and distributes systemically after inhalation.The purpose of this study was to determine the protective efficacy of a single dose of molecular hydrogen (H-2) on cochlear structures. Guinea pigs were divided into six groups and sacrificed immediately after or at 1 or 2 weeks. The animals were exposed to broadband noise for 2 h directly followed by 1-h inhalation of 2% H-2 or room air. Electrophysiological hearing thresholds using frequency-specific auditory brainstem response (ABR) were measured prior to noise exposure and before sacrifice. ABR thresholds were significantly lower in H-2-treated animals at 2 weeks after exposure, with significant preservation of outer hair cells in the entire cochlea. Quantification of synaptophysin immunoreactivity revealed that H-2 inhalation protected the cochlear inner hair cell synaptic structures containing synaptophysin. The inflammatory response was greater in the stria vascularis, showing increased Iba1 due to H-2 inhalation.Repeated administration of H-2 inhalation may further improve the therapeutic effect. This animal model does not reproduce conditions in humans, highlighting the need for additional real-life studies in humans.
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| 5. |
- Pierre, Pernilla Videhult, et al.
(författare)
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Cisplatin-induced metabolome changes in serum : an experimental approach to identify markers for ototoxicity
- 2017
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Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 137:10, s. 1024-1030
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Ototoxicity from treatment with the anticancer drug cisplatin remains a clinical problem. A wide range of intracellular targets of cisplatin has been found in vivo.AIM: To investigate cisplatin-induced change of the serum metabolite profile and its association with ototoxicity.MATERIAL AND METHODS: Guinea pigs (n = 14) were treated with cisplatin (8 mg/kg b.w., i.v.) 30 min after administration of the otoprotector candidate sodium thiosulfate (group STS; n = 7) or sodium chloride (group NaCl; n = 7). Ototoxicity was evaluated by ABR (3-30 kHz) before and 4 d after drug treatment, and by assessment of hair cell loss. A blood sample was drawn before and 4 d after drug treatment and the polar metabolome in serum was analyzed using LC-MS.RESULTS: Cisplatin-treatment caused significant threshold elevations and outer hair cell (OHC) loss in both groups. The ototoxicity was generally lower in group STS, but a significant difference was reached only at 30 kHz (p = .007). Cisplatin treatment altered the metabolite profile significantly and similarly in both groups. A significant inverse correlation was found between L-acetylcarnitine, N-acetylneuraminic acid, ceramide, and cysteinylserine and high frequency hearing loss in group NaCl. The implication of these correlations should be explored in targeted studies.
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| 6. |
- Pierre, Pernilla Videhult, et al.
(författare)
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High-Dose Furosemide Enhances the Magnetic Resonance Signal of Systemic Gadolinium in the Mammalian Cochlea
- 2020
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Ingår i: Otology and Neurotology. - : LIPPINCOTT WILLIAMS & WILKINS. - 1531-7129 .- 1537-4505. ; 41:4, s. 545-553
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Tidskriftsartikel (refereegranskat)abstract
- Hypothesis:Furosemide alters the permeability of the intrastrial fluid-blood barrier.Background:The cochlear sensory cells are protected by the blood-perilymph and intrastrial fluid-blood barriers, which hinder substances, including gadolinium-based contrast agents (GdCAs), to enter the endolymphatic space. High-dose furosemide causes transient shift of hearing thresholds and morphological changes in stria vascularis. Furosemide is also known to enhance drug-induced ototoxicity.Methods:Furosemide (400mg/kg b.w.) was injected i.v. in Balb/C mice (n=20). Twenty minutes later, the GdCA gadobutrol, gadopentetic acid, or gadoteric acid was injected i.v. The distribution of GdCA to the perilymphatic and endolymphatic spaces was studied with MRI (9.4T) for 250minutes.Results:The perilymphatic and endolymphatic spaces were signal-enhanced in all animals. Gadopentetic acid and gadoteric acid yielded similar signal enhancement in all three scalae, while gadobutrol yielded significantly higher enhancement in scala tympani than scala media (p=0.043) and scala vestibuli (p=0.043). The signal enhancement reached a plateau but did not decrease during the time of observation.Conclusion:Treatment with a high dose of furosemide before injection of a GdCA resulted in enhancement of the MRI signal in the endolymphatic space as well as the perilymphatic space, which supports our hypothesis that furosemide alters the permeability of the intrastrial fluid-blood barrier.
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| 7. |
- Pierre, Pernilla Videhult, et al.
(författare)
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Subjective and Clinically Assessed Hearing Loss; A Cross-Sectional Register-Based Study on a Swedish Population Aged 18 through 50 Years
- 2015
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 10:4
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Tidskriftsartikel (refereegranskat)abstract
- Objectives Questionnaire studies suggest that hearing is declining among young adults. However, few studies have examined the reliability of hearing questionnaires among young adult subjects. This study examined the associations between pure tone audiometrically assessed (PTA) hearing loss and questionnaire responses in young to middle aged adults. Materials and Methods A cross-sectional study using questionnaire and screening PTA (500 through 6000 Hz) data from 15322 Swedish subjects (62% women) aged 18 through 50 years. PTA hearing loss was defined as a hearing threshold above 20 dB in both ears at one or more frequencies. Data were analysed with chi-square tests, nonlinear regression, binary logistic regression, and the generalized estimating equation (GEE) approach. Results The prevalence of PTA hearing loss was 6.0% in men and 2.9% in women (p less than 0.001). Slight hearing impairment was reported by 18.5% of the men and 14.8% of the women (p less than 0.001), whereas 0.5% of men and women reported very impaired hearing. Using multivariate GEE modelling, the odds ratio of PTA hearing loss was 30.4 (95% CI, 12.7-72.9) in men and 36.5 (17.2-77.3) in women reporting very impaired hearing. The corresponding figures in those reporting slightly impaired hearing were 7.06 (5.25-9.49) in men and 8.99 (6.38-12.7) in women. These values depended on the sound stimulus frequency (p = 0.001). The area under the ROC curve was 0.904 (0.892-0.915) in men and 0.886 (0.872-0.900) in women. Conclusions Subjective hearing impairment predicted clinically assessed hearing loss, suggesting that there is cause for concern as regards the future development of hearing in young to middle-aged people.
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| 8. |
- Pirttilä, Kristian, et al.
(författare)
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An LCMS-based untargeted metabolomics protocol for cochlear perilymph : highlighting metabolic effects of hydrogen gas on the inner ear of noise exposed Guinea pigs
- 2019
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Ingår i: Metabolomics. - : Springer Science and Business Media LLC. - 1573-3882 .- 1573-3890. ; 15:10
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Noise-induced hearing loss (NIHL) is an increasing problem in society and accounts for a third of all cases of acquired hearing loss. NIHL is caused by formation of reactive oxygen species (ROS) in the cochlea causing oxidative stress. Hydrogen gas (H-2) can alleviate the damage caused by oxidative stress and can be easily administered through inhalation.Objectives To present a protocol for untargeted metabolomics of guinea pig perilymph and investigate the effect of H-2 administration on the perilymph metabolome of noise exposed guinea pigs.Methods The left ear of guinea pigs were exposed to hazardous impulse noise only (Noise, n = 10), noise and H-2 (Noise + H2, n = 10), only H-2 (H2, n = 4), or untreated (Control, n = 2). Scala tympani perilymph was sampled from the cochlea of both ears. The polar component of the perilymph metabolome was analyzed using a HILIC-UHPLC-Q-TOF-MS-based untargeted metabolomics protocol. Multivariate data analysis (MVDA) was performed separately for the exposed- and unexposed ear.Results MVDA allowed separation of groups Noise and Noise + H2 in both the exposed and unexposed ear and yielded 15 metabolites with differentiating relative abundances. Seven were found in both exposed and unexposed ear data and included two osmoprotectants. Eight metabolites were unique to the unexposed ear and included a number of short-chain acylcarnitines.Conclusions A HILIC-UHPLC-Q-TOF-MS-based protocol for untargeted metabolomics of perilymph is presented and shown to be fit-for-purpose. We found a clear difference in the perilymph metabolome of noise exposed guinea pigs with and without H-2 treatment.
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| 9. |
- Pirttilä, Kristian, et al.
(författare)
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LCMS-based untargeted metabolomics of guinea pig perilymph using a novel separation method for sequential analysis of hydrophilic and lipophilic compounds: Studying the effect of hydrogen gas on noise-induced hearing loss
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Noise-induced hearing loss (NIHL) is believed to be caused by oxidative stress and accounts for up to a third of all cases of acquired hearing loss worldwide. The use of hydrogen gas as a mitigating treatment for NIHL has been successfully demonstrated in the past. We here present the application of a novel LC/LC-HRMS method for sequential analysis of hydrophilic and lipophilic compounds on an untargeted metabolomics study of the attenuating effect of hydrogen gas on NIHL in guinea pigs. The study was conducted using perilymph taken from the basal turn of the cochlea. Samples were taken in the acute stage, immediately following noise exposure along with follow-up samples after 1 and 2 weeks. Data analysis using volcano plots and random forest discriminant models revealed differences in the concentration of potassium within the scala tympani indicating effects on the potassium recycling system of the inner ear. Additionally, discriminant levels of glycerophosphorylcholine, a common osmolyte and antioxidant were discovered. In addition to these two compounds, four additional unknown metabolites are described. The findings are in line with previous reports indicating that the protective effect of hydrogen gas is sustained for at least 2 weeks.
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| 10. |
- Videhult Pierre, Pernilla
(författare)
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Cisplatin : a platinum-containing antineoplastic drug : perspectives on analytical chemistry and prevention of ototoxicity
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The platinum-containing drug cisplatin plays a key role in the curative and palliative treatment of many solid malignancies. Unfortunately, the treatment can lead to sensorineural hearing loss, which limits the use of the drug. High single and cumulative dose levels are risk factors, but there is a large interindividual variability in the susceptibility to the ototoxic effects. The mechanisms behind the ototoxicity have not been fully elucidated, but one hallmark is oxidative stress. Moreover, the ototoxicity is dependent on the exposure of cisplatin and/or its biotransformation product MHC in the perilymphatic compartment of the cochlea. The aim of the research presented in this thesis was to contribute to the development of treatment strategies against cisplatin-induced ototoxicity. Sulfur-containing nucleophiles are attractive candidate compounds against cisplatin- induced hearing loss since they are prone to chemically interact with cisplatin and MHC and could potentially reduce the exposure of these platinum species in the cochlea. A second possible mechanism may be relief of oxidative stress. The aim of the in vitro study described in Paper I was to investigate how quickly the concentrations of cisplatin and MHC can be reduced in the presence of five sulfur-containing nucleophiles. The results showed that thiosulfate was a promising candidate for future studies in vivo, since it reacted fast with cisplatin and, in particular, with MHC. This conclusion was further supported by the fact that thiosulfate is an endogenous ion, is well tolerated, and has been used clinically for decades against e.g. cyanide poisoning. Systemic administration of thiosulfate has earlier been investigated in several in vitro and in vivo studies against cisplatin-induced ototoxicity. However, it has been unknown whether thiosulfate at all reaches the cochlea. In the study described in Paper II, it was demonstrated that the distribution of thiosulfate to the perilymphatic compartment was quick and extensive after an i.v. bolus injection in guinea pigs. Unfortunately, this way of administration of thiosulfate in connection with systemic cisplatin delivery is risky, since it may lead to decreased antitumoral effects due to inactivation of cisplatin and MHC not only in the cochlea but also in tumor tissues. In the studies on which Paper III is based, it was found that the ototoxicity in cisplatin-treated guinea pigs was reduced by a local administration strategy employing a thiosulfate-containing hyaluronan gel administered into the middle ear cavity three hours prior to the systemic cisplatin injection. When quantifying cisplatin, unselective methods are almost always used, which may confound the results. In the final study, on which Paper IV is based, a sensitive, robust, and fast method using liquid chromatography and UV detection for the selective analysis of cisplatin in blood was developed. This method will be a valuable instrument in future studies exploring the role of pharmacokinetic parameters of cisplatin for the ototoxic effects.
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| 11. |
- Videhult Pierre, Pernilla, et al.
(författare)
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High concentrations of thiosulfate in scala tympani perilymph after systemic administration in the guinea pig
- 2009
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Ingår i: Acta Oto-Laryngologica. - Oslo : Taylor & Francis. - 0001-6489 .- 1651-2251. ; 129:2, s. 132-137
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Tidskriftsartikel (refereegranskat)abstract
- CONCLUSION: High concentrations of the antioxidant thiosulfate reach scala tympani perilymph after i.v. administration in the guinea pig. Thiosulfate concentrations in perilymph remain elevated longer than in blood. This warrants further studies on the possibility of obtaining otoprotection by thiosulfate administration several hours before that of cisplatin without compromising the anticancer effect caused by cisplatin inactivation in the blood compartment.OBJECTIVE: Thiosulfate may reduce cisplatin-induced ototoxicity, presumably by oxidative stress relief and formation of inactivate platinum complexes. This study aimed to explore to what extent thiosulfate reaches scala tympani perilymph after systemic administration in the guinea pig.MATERIALS AND METHODS: Scala tympani perilymph (1 microl) was aspirated from the basal turn of each cochlea up to 3 h after thiosulfate administration (103 mg/kg b.w., i.v.). Blood samples were also taken. Thiosulfate was quantified by HPLC and fluorescence detection.RESULTS: Substantial thiosulfate concentrations were found in perilymph. The area under the concentration-time curve for thiosulfate in perilymph and blood was 3100 microMxmin and 6300 microMxmin, respectively. The highest thiosulfate concentrations in perilymph were found at the first sampling at about 10 min. Due to a more rapid elimination from blood, perilymph concentrations exceeded those of blood towards the end of the experiment.
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| 12. |
- Videhult Pierre, Pernilla, et al.
(författare)
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Hydrogen Gas Inhalation Attenuates Acute Impulse Noise Trauma : A Preclinical In Vivo Study
- 2022
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Ingår i: Annals of Otology, Rhinology and Laryngology. - : Sage Publications. - 0003-4894 .- 1943-572X. ; 132:8, s. 865-872
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Molecular hydrogen (H2) has shown therapeutic potential in several oxidative stress-related conditions in humans, is well-tolerated, and is easily administered via inhalation.The aim of this preclinical in vivo study was to investigate whether impulse noise trauma can be prevented by H2 when inhaled immediately after impulse noise exposure.Methods: Guinea pigs (n = 26) were subjected to impulse noise (n = 400; 156 dB SPL; 0.33/s; n = 11; the Noise group), to impulse noise immediately followed by H2 inhalation (2 mol%; 500 ml/min; 1 hour; n = 10; the Noise + H2 group), or to H2 inhalation (n = 5; the H2 group). The acoustically evoked ABR threshold at 3.15, 6.30, 12.5, 20.0, and 30.0 kHz was assessed before and 4 days after impulse noise and/or H2 exposure. The cochleae were harvested after the final ABR assessment for quantification of hair cells.Results: Noise exposure caused ABR threshold elevations at all frequencies (median 35, 35, 30, 35, and 35 dB SPL, the Noise group; 20, 25, 10, 13, and 20 dB SPL, the Noise + H2 group; P < .05) but significantly less so in the Noise + H2 group (P < .05). Outer hair cell (OHC) loss was in the apical, mid, and basal regions 8.8%, 53%, and 14% in the Noise group and 3.5%, 22%, and 1.2% in the Noise + H2 group. The corresponding inner hair cell (IHC) loss was 0.1%, 14%, and 3.5% in the Noise group and 0%, 2.8%, and 0% in the Noise + H2 group. The difference between the groups was significant in the basal region for OHCs (P = .003) and apical (P = .033) and basal (P = .048) regions for IHCs.Conclusions: Acute acoustic trauma can be reduced by H2 when inhaled immediately after impulse noise exposure.
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| 13. |
- Videhult Pierre, Pernilla, et al.
(författare)
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Middle Ear Administration of a Particulate Chitosan Gel in an in vivo Model of Cisplatin Ototoxicity
- 2019
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Ingår i: Frontiers in Cellular Neuroscience. - : Frontiers Media SA. - 1662-5102. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Background: Middle ear (intratympanic, IT) administration is a promising therapeutic method as it offers the possibility of achieving high inner ear drug concentrations with low systemic levels, thus minimizing the risk of systemic side effects and drug-drug interactions. Premature elimination through the Eustachian tube may be reduced by stabilizing drug solutions with a hydrogel, but this raises the secondary issue of conductive hearing loss.Aim: This study aimed to investigate the properties of a chitosan-based particulate hydrogel formulation when used as a drug carrier for IT administration in an in vivo model of ototoxicity.Materials and Methods: Two particulate chitosan-based IT delivery systems, Thio-25 and Thio-40, were investigated in albino guinea pigs (n = 94). Both contained the hearing protecting drug candidate sodium thiosulfate with different concentrations of chitosan gel particles (25% vs. 40%). The safety of the two systems was explored in vivo. The most promising system was then tested in guinea pigs subjected to a single intravenous injection with the anticancer drug cisplatin (8 mg/kg b.w.), which has ototoxic side effects. Hearing status was evaluated with acoustically evoked frequency-specific auditory brainstem response (ABR) and hair cell counting. Finally, in vivo magnetic resonance imaging was used to study the distribution and elimination of the chitosan-based system from the middle ear cavity in comparison to a hyaluronan-based system.Results: Both chitosan-based IT delivery systems caused ABR threshold elevations (p < 0.05) that remained after 10 days (p < 0.05) without evidence of hair cell loss, although the elevation induced by Thio-25 was significantly lower than for Thio-40 (p < 0.05). Thio-25 significantly reduced cisplatin-induced ABR threshold elevations (p < 0.05) and outer hair cell loss (p < 0.05). IT injection of the chitosan- and hyaluronan-based systems filled up most of the middle ear space. There were no significant differences between the systems in terms of distribution and elimination.Conclusion: Particulate chitosan is a promising drug carrier for IT administration. Future studies should assess whether the physical properties of this technique allow for a smaller injection volume that would reduce conductive hearing loss.
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| 14. |
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| 15. |
- Videhult Pierre, Pernilla, et al.
(författare)
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Self-reported hearing difficulties, main income sources, and socio-economic status; a cross-sectional population-based study in Sweden
- 2012
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Ingår i: BMC Public Health. - : Springer Science and Business Media LLC. - 1471-2458. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Hearing difficulties constitute the most common cause of disability globally. Yet, studies on people with hearing difficulties regarding socio-economic status (SES), work, long-term unemployment, sickness absence, and disability pension are scarce. The aim of the present study was to investigate the main income sources of men and women of working ages with and without self-reported hearing difficulties and associations with gender, age, SES, type of living area, and country of birth.METHODS: A cross-sectional population-based study, using information on self-reported hearing difficulties and SES of 19 045 subjects aged 20-64 years participating in Statistics Sweden's annual Living Conditions Surveys in any of the years 2004 through 2008. The information was linked to a nationwide database containing data on demographics and income sources. Odds ratios (ORs) and their 95% confidence intervals (CIs) were calculated, using binary logistic regression analysis.RESULTS: Hearing difficulties increased with age and were more common in men (age-adjusted OR: 1.42 (95% CI: 1.30-1.56)) with an overall prevalence of 13.1% in men and 9.8% in women. Using working men as reference, the OR of having hearing difficulties was 1.23 (0.94-1.60) in men with unemployment benefits and 1.36 (1.13-1.65) in men with sickness benefits or disability pension, when adjusting for age and SES. The corresponding figures in women were 1.59 (1.17-2.16) and 1.73 (1.46-2.06). The OR of having sickness benefits or disability pension in subjects with hearing difficulties was 1.36 (1.12-1.64) in men and 1.70 (1.43-2.01) in women, when adjusting for age and SES and using men and women with no hearing difficulties as reference.CONCLUSIONS: Hearing difficulties were more prevalent in men. After adjustment with age and SES as well as with type of living area and country of birth, a significant association with unemployment benefits was found only in women, and the associations with long-term sickness absence and disability pension tended to be stronger in women.
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