Analysis of genetic and non genetic risk factors for cisplatin ototoxicity in pediatric patients

OBJECTIVE

The aim of this study was to analyse the genetic and non genetic risk factors for cisplatin ototoxicity.

METHODS

This study was conducted on 72 children who received cisplatin based chemotherapy. Brock and Muenster classifications were used to evaluate ototoxicity seen in these children. 6 single nucleotide polymorphisms (SNP); ERCC1 rs 11615, GSTP1 rs1138272, GSTP1 rs1695, LRP2 rs 2075252, TPMT rs 12201199, COMT rs 9332377, were evaluated as genetic factors by real time PCR. Non genetic factors such as cranial irradiation, cumulative doses of cisplatin, age, gender, administration of other ototoxic drugs were analysed as well. By using Chi-square test, risk factors were matched with the ototoxicity classifications. Significant risk factors were reevaluated using logistic regression modelling.

RESULTS

According to univariate analyses, male gender, co-treatment with aminoglycosides and mutant genotype of GSTP1 rs1695 were significantly related with cisplatin ototoxicity. Logistic regression modelling analyses also showed that male gender, co-treatment with aminoglycosides were found to be significantly related with cisplatin ototoxicity. Mutant genotype of GSTP1 rs1695 was not found to be significant, but close to the level of statistical significance.

CONCLUSION

Male gender, co-treatment with aminoglycosides are significant risk factors for cisplatin ototoxicity in pediatric patients. Mutant genotype of GSTP1 rs1695 seems to be a genetic risk factor in univariate analyses, although not confirmed by multivariate analyses. Therefore, GSTP1 rs1695 SNP needs to be studied in larger series.

Comparison of Audiological Findings in Patients with Vestibular Migraine and Migraine

Objective

The aim of this study was to investigate and compare the auditory findings in vestibular migraine (VM) and migraine patients without a history of vertigo.

Methods

This study was conducted on 44 patients diagnosed with definite VM and 31 patients diagnosed with migraine who were followed and treated between January 2011 and February 2015. Also, 52 healthy subjects were included in this study as a control group. All participants underwent a detailed otorhinolaryngological examination followed by audiological evaluation, including pure tone audiometry, speech reception threshold, speech recognition score, and acoustic immitancemetry.

Results

In the VM group, there were 16 patients (36.4%) with tinnitus, while in the other groups we did not observe any patients with tinnitus. The rate of tinnitus in the VM group was significantly higher in comparison to other groups (p<0.05). None of the groups had any patients with permanent or fluctuating sensorineural hearing loss.

Conclusion

We conclude that patients with VM should be closely and longitudinally followed up for the early detection of other otological symptoms and possible occurrence of sensorineural hearing loss in the long term.

The Effect of Tympanic Membrane Perforation Site, Size and Middle Ear Volume on Hearing Loss

Objective

The aim of this study was to analyze the location and the size of perforation in cases with tympanic membrane perforation, its relation to the manubrium mallei and middle ear volume, and to investigate how these are correlated with the severity and frequencies of conductive hearing loss.

Methods

This prospectively designed study included the patients who presented to the the Department of Otorhinolaryngology at the Dokuz Eylül University with hearing loss or tinnitus complaints in the period from June 2014 through June 2017 and were identified to have tympanic membrane perforation in their otoscopic examination. Patients who underwent myringoplasty and type 1 tympanoplasty and whose air-bone gap was found lower than 10 dB in the postoperative audiological examination were included in the study. Effects of the perforation size, the perforation site, and the relationship of the perforation with the manubrium, as well as the effects of the middle ear volume on the severity and frequency of conductive hearing loss were compared.

Results

The study included 44 ears of 38 patients (13 male and 25 female) of whom six had tympanic membrane perforation in both ears. Air conduction threshold and air-bone gap were significantly found higher if the perforation area was wide (p<0.05), the perforation involved both the anterior and the posterior quadrants (p<0.05), had contact with the manubrium mallei (p<0.05), and the middle ear volume reduced (p<0.05).

Conclusion

Solely tympanic membrane perforation affects hearing function; nevertheless, hearing function are better in cases, which have perforations small in size, no contact with manubrium mallei and well pneumatized middle ears.

Otoprotective effect of recombinant erythropoietin in a model of newborn hypoxic-ischemic encephalopathy

OBJECTIVE

The aim of this study is to test the hypotheses that central auditory pathology as well as inner ear pathology is contributing mechanisms to observed hypoxic-ischemic encephalopathy (HIE) induced hearing loss and that recombinant erythropoietin (rhEPO) will reduce this cellular pathology and attenuate hearing loss.

METHODS

Twenty-eight 7-day Wistar albino rat pups were divided into four groups: Control group (n=8) was given only intraperitoneal saline solution. Sham group (n=5) had only a midline neck incisions without carotid ligation under general anesthesia and administration of intraperitoneal saline solution. HIE group (n=8) and rhEPO treated group (n=7) were subjected to left common carotid artery ligation followed by 2.5h hypoxia exposure to a mixture of 8% oxygen and 92% pure nitrogen. HIE group was injected with intraperitoneal saline solution, while the rhEPO treated group received rhEPO 100 U/kg within the same volume as the saline-alone solution. At the end of the seventh week of age hearing (ABRs) was evaluated in response to clicks, 6 kHz and 8 kHz tone burst stimuli. Animals were sacrificed and both temporal lobes, cochleas and brainstems of the animals were collected. Tissue samples were evaluated with light microscopy, immunohistochemical studies, including TUNEL and caspase-3 stainings, and electron microscopy.

RESULTS

Hearing thresholds were elevated in HIE animals. In rhEPO treated animals, ABR values were similar to controls. HIE caused apoptotic changes in brainstem structures as shown by light microscopy and immunohistochemical methods. Apoptotic changes also were found within the organ of Corti, spiral ganglion cells and neurons of temporal lobe by electron microscopic investigation. In rhEPO animals many of these apoptotic changes were observed, but reduced compared to untreated animals.

CONCLUSIONS

Mechanisms underlying HIE-induced hearing loss are based on apoptosis in inner ear; however central auditory pathway pathology occurs as well, likely contributing to changes in auditory processing and perception of complex signals not reflected by the ABR threshold shifts. For both clinical and basic significance 'rhRPO' is found to reduce those effects.

Cognitive function in Meniere's disease

Meniere's disease is an otological disease characterized by various symptoms that include episodic peripheral vertigo, sensorineural hearing loss, tinnitus, and aural fullness, all of which deteriorate the maintenance of daily activities. We aimed to investigate cognitive function in Meniere's disease patients and compare their results to those of healthy controls. Eighteen patients diagnosed with definite Meniere's disease without any psychiatric, neurological or otological comorbidity, and 30 healthy controls with normal cognitive functions were included in the study. General cognitive status, attention, verbal memory, visual memory, executive and visuospatial function were measured by detailed neuropsychological tests in both groups. In the patients with Meniere's disease, pure-tone hearing thresholds, and speech discrimination scores were also measured. Patients with Meniere's disease showed lower levels of performance in the trail making test, Oktem verbal memory processes, Rey Complex Figure Test, Wisconsin Card Sorting Test, semantic and phonemic fluency than did healthy controls. In other words, there were deficits in attention, recognition and recall in verbal memory, recall in visual memory, visual spatial construction, and planning skills in patients with Meniere's disease. Education years and depression scores of participants had a significant effect on cognitive function in all groups. This study is an update and confirmation of the findings of studies showing cognitive impairment in patients with Meniere's disease. In addition to previous findings, this study found a decrease in executive function performance in patients with Meniere's disease compared to healthy controls. Unlike previous studies, this study comprehensively addressed all cognitive functions and included a control group. Our results emphasize that executive functions, which are high-level cognitive processes, may affect the compliance of patients with Meniere's disease treatment and follow-up processes.

Apoptotic Effects of Sanguinarine on the Organ of Corti 1 Cells: Comparison with Cisplatin

OBJECTIVE

Sanguinarine is an alkaloid obtained from the root of Sanguinaria canadensis and other plants from the Papaveraceae family and is well known to possess a broad range of biological functions, such as antimicrobial, antifungal, anti-inflammatory, and antineoplastic activities. We aimed to specify the in vitro effect of sanguinarine on the House Ear Institute-Organ of Corti 1 (HEI-OC1) cells and to compare this effect with the ototoxic effect of cisplatin (CDDP).

MATERIALS AND METHODS

We performed cell proliferation assay for determining the in vitro effect of sanguinarine alone and compared it with the effect of cisplatin. Flow cytometry annexin-V apoptosis detection was performed.

RESULTS

We found that sanguinarine and CDDP inhibited the cell growth in a dose-dependant manner in HEI-OC1 cells after 24 h of incubation. In sanguinarine-treated group, apoptosis was 6.6%, necrosis was 26.7%, and the cell viability was 66.7%. Further, in CDDP-treated group, apoptosis was 5.6%, necrosis was 45.4%, and the cell viability was 48.7%. According to the annexin-V apoptosis detection results, we found that sanguinarine caused 3.9% apoptosis and 1.3% necrosis, while CDDP caused 2.9% apoptosis and 20% necrosis on HEI-OC1 cells.

CONCLUSION

Our findings suggested that lower doses of sanguinarine are promising antineoplastic agents, which did not indicate any toxic effect on HEI-OC1 cells. Application of these data to clinical practice requires further support by in vivo studies.

Cyclosporine causes no hearing defect in paediatric patients with nephrotic syndrome

OBJECTIVE

We aimed to evaluate the ototoxicity of cyclosporine A (CsA) in children with nephrotic syndrome (NS).

DESIGN

Data of paediatric patients with NS followed in paediatric nephrology department were evaluated retrospectively, and hearing functions were evaluated by pure tone audiometry (PTA) and transient evoked otoacoustic emissions (TEOAEs). Age, gender, type of NS, duration and cumulative doses of immunosuppressives were noted.

STUDY SAMPLE

The patients who had received CsA (n: 16) and immunosuppressives other than CsA (n: 13) for at least 6 months formed two patient groups and healthy cases formed a control group (n: 20). Children with known previous hearing defect, inner ear trauma or surgery, recurrent otitis media and those using hearing aid were excluded.

RESULTS

Gender, age at first clinical presentation, laboratory tests and number of relapses were similar between the groups. No hearing loss was defined in PTA at frequencies of 250, 500, 1000, 2000, 4000 and 8000 Hz. The results of TEOAEs were similar between the groups and compatible with normal hearing.

CONCLUSIONS

CsA is not responsible for permanent sensorineural hearing loss in children with NS, and there is no sufficient evidence to consider routine hearing assessment in children with NS treated with CsA.

Effect of Korean Red Ginseng on Noise-Induced Hearing Loss

Objective:

Noise-induced hearing loss (NIHL) is one of the most important problems affecting both social and professional life of patients. There is no treatment method considered to be successful on the hearing loss that has become a permanent nature. Aim of this study is to evaluate protective effect of Korean Red Ginseng (KRG) against NIHL in an animal model.

Methods:

Twenty-eight rats were separated into four groups [control saline (group I), control KRG (group II), saline + noise (group III), KRG + noise (group IV)]. Rats in the saline and KRG groups were fed via oral gavage with a dose of 200 mg/kg/day throughout for 10 days. Fourteen rats (group III and IV) were exposed to 4 kHz octave band noise at 120 dB SPL for 5 hours. Hearing levels of rats were evaluated by distortion product otoacoustic emissions (DPOAE) and auditory brainstem responses (ABR) at 4, 8, 12, 16 and 32 kHz frequencies prior to and on days 1, 7 and 10 after the noise exposure. Rats were sacrificed on 10th day, after the last audiological test. Cochlea and spiral ganglion tissues were evaluated by light microscopy.

Results:

Audiological and histological results demonstrated that after noise the group IV showed better results than group III. In the noise exposed groups, the most prominent damage was seen at the 8 kHz frequency region than other regions. After the noise exposure, DPOAE responses were lost in 1st, 7th and 10th measurements in both group III and IV. Thus, we were not able to perform any statistical analyses for DPOAE results.

Conclusion:

Our findings suggest that KRG seems to be an efficient agent against NIHL. There is need for additional research to find out about the mechanisms of KRG’s protective effect.

The Reliability and Validity of "Dokuz Eylül University Meniere's Disease Disability Scale"

OBJECTIVE

Ménière's Disease (MD) is a chronic, non-life threatening inner ear disease, with attacks of disabling vertigo, progressive hearing loss, and tinnitus as the major symptoms. All three symptoms, separately or in combination, cause great distress and have a considerable impact on the quality of life of the patients. The aims of this study were to develop a disease-specific quality of life survey for patients with MD and to analyze the relationships between the audiovestibular findings and the survey.

MATERIALS AND METHODS

Following Ear-Nose-Throat examination and audiovestibular tests, the Dokuz Eylül University Meniere's Disease Disability Scale (DEU-MDDS) and Turkish version of the Dizziness Handicap Inventory (DHI-T) were administered to 93 patients with definite MD. Reliability and validity analyses of the scale were performed.

RESULTS

There were 45 (48.4%) male and 48 (51.6%) female patients and the mean age was 48.9±12.1 years. Cronbach's alpha was 0.92 and intraclass correlation coefficients of the DEU-MMDS were significant (p<0.001). Results of the Goodness of Fit Statistics showed that the expression levels of the items were high and the correlation coefficients of each item with the scale were sufficient. There was a statistically significant correlation between DHI-T scores and MDDS. DEU-MDDS was not related to the vestibular tests, age or gender (p>0.05).

CONCLUSION

The MDDS is a valid and reliable scale as a disease-specific quality of life questionnaire for patients with MD.

Comparison of Cortical Auditory Evoked Potential Findings in Presbycusis with Low and High Word Recognition Score

BACKGROUND

Deteriorated speech understanding is a common complaint in elderly people, and behavioral tests are used for routine clinical assessment of this problem. Cortical auditory evoked potentials (CAEPs) are frequently used for assessing speech detection and discrimination abilities of the elderly, and give promise for differential diagnosis of speech understanding problems.

PURPOSE

The aim of the study was to compare the P1, N1, and P2 CAEP latencies and amplitudes in presbycusis with low and high word recognition score (WRS).

RESEARCH DESIGN

A cross-sectional study design was used for the study. Two groups were formed from the patients with presbycusis based on their scores on the speech recognition test.

STUDY SAMPLE

Fifty-seven elderly volunteers participated in the study. The first group composed of 27 participants with high WRS, the other group composed of 30 participants with low WRS.

DATA COLLECTION AND ANALYSIS

The CAEP waves were recorded from these participants using speech signals. Latencies and amplitudes of P1-N1-P2 waves of the two groups were compared with the t-test statistic.

RESULTS

There were significant prolongation of P1 and N1 latencies in presbycusis with low WRS when compared with presbycusis with a relatively high word score (p < 0.05).

CONCLUSION

According to the result of the research, P1 and N1 latencies of presbycusis with low WRS were longer than the participants with high WRS. Factors affecting peripheral auditory system, such as stimulus sensation level, might be responsible for P1 and N1 latency prolongation of the low WRS group.

Comparison of Cortical Auditory Evoked Potential Findings in Presbycusis with Low and High Word Recognition Score

BACKGROUND

Deteriorated speech understanding is a common complaint in elderly people, and behavioral tests are used for routine clinical assessment of this problem. Cortical auditory evoked potentials (CAEPs) are frequently used for assessing speech detection and discrimination abilities of the elderly, and give promise for differential diagnosis of speech understanding problems.

PURPOSE

The aim of the study was to compare the P1, N1, and P2 CAEP latencies and amplitudes in presbycusis with low and high word recognition score (WRS).

RESEARCH DESIGN

A cross-sectional study design was used forthe study. Two groups were formed from the patients with presbycusis based on their scores on the speech recognition test.

STUDY SAMPLE

Fifty-seven elderly volunteers participated in the study. The first group composed of 27 participants with high WRS, the other group composed of 30 participants with low WRS.

DATA COLLECTION AND ANALYSIS

The CAEP waves were recorded from these participants using speech signals. Latencies and amplitudes of P1 -N1-P2 waves of the two groups were compared with the f-test statistic.

RESULTS

There were significant prolongation of P1 and N1 latencies in presbycusis with low WRS when compared with presbycusis with a relatively high word score (p < 0.05).

CONCLUSION

According to the result of the research, P1 and N1 latencies of presbycusis with low WRS were longer than the participants with high WRS. Factors affecting peripheral auditory system, such as stimulus sensation level, might be responsible for P1 and N1 latency prolongation of the low WRS group.

Examination and Comparison of Electrically Evoked Compound Action Potentials and Electrically Evoked Auditory Brainstem Response Results of Children with Cochlear Implantation without Inner Ear Anomaly

Objective

To investigate the relationship between electrically evoked compound action potentials (ECAP) and electrically evoked auditory brainstem responses (EABR) in children with cochlear implants (CI) without inner ear anomalies.

Methods

Sixteen children between the ages of two and six years who were CI users participated in the study. ECAP thresholds were recorded from one electrode in the basal, medial, and apical regions of the cochlear implant. EABRs were recorded from electrodes whose ECAP thresholds were determined. The latency-intensity functions, amplitude and morphological analyzes of the eIII and eV waves at 200 and 180 current unit (CU) excitation levels were performed. The data obtained were analyzed statistically.

Results

ECAP thresholds were found to be 171.5±11.38, 169.69±20.32 and 160.81±20.03 CU at the basal, medial and apical electrodes, respectively. EABR thresholds were also found to be 169.69±12.17, 165.62±16.41 and 160±15.49 CU in basal, medial and apical electrodes, respectively. There was a strong positive correlation between ECAP and EABR thresholds in apical, medial and basal electrodes (p<0.05). EABR threshold levels were not significantly different between basal, medial and apical region electrodes (p>0.05), and ECAP threshold values were significantly different between apical and basal region electrodes (p=0.002). When the significance values of EABR eV wave latencies were analyzed in terms of electrode region, the difference between basal and apical regions was found to be significant (p=0.03).

Conclusion

Consistency was found between ECAP and EABR recordings. However, it was concluded that one could not be preferred over the other because the data quality of the two tests was different. In future studies, ECAP and EABR recordings may be recommended by selecting more electrodes for stimulation.

Comparison of Cytotoxic and Ototoxic Effects of Lipoplatin and Cisplatin in Neuroblastoma In Vivo Tumor Model

BACKGROUND

This study aimed to compare the cytotoxic, cytostatic, and ototoxic effects of lipoplatin compared to cisplatin application in the subcutaneous xenograft nude mouse neuroblastoma tumor model.

METHODS

In this study, C1300 neuroblastoma cells were administered subcutaneously to 21 male nude mice. When the tumor reached 150 mm3 diameter, mice were randomized into 3 groups. Saline, cisplatin, and lipoplatin were given intraperitoneally. The auditory function tests were performed before administration and 72 hours after administration. Mice were sacrificed and the tumor and cochlea were removed after 72 hours. Histopathologic evaluation of necrosis and apoptosis was determined by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method. Cyclooxygenase 2, superoxide dismutase 2, and inducible nitric oxide synthase levels were determined by immunohistochemistry in tissue samples.

RESULTS

Apoptosis and necrosis rates were higher in lipoplatin group than in cisplatin group (P=.035 and P=.010, respectively) in tumor tissue. In the spiral ganglion, apoptosis and necrosis were lower in the lipoplatin group than in cisplatin group (P=.002 and P=.002, respectively). Cyclooxygenase 2 pattern in the cochlea was positive in both control and lipoplatin group and negative in cisplatin group (P=.001). Superoxide dismutase 2 and inducible nitric oxide synthase 2 protein expressions showed no difference between groups. The auditory functions were similar to baseline values and had a better threshold value in lipoplatin group than cisplatin group.

CONCLUSION

For the treatment of neuroblastoma, the use of lipoplatin seems to be beneficial in reducing side effects of cisplatin. We recommend that the mechanism of these properties of lipoplatin should be evaluated in further studies.

Effects of Cross-linked Hyaluronic Acid in a Rat Model of Vestibular and Cochlear Toxicity

Objective

To investigate the effects of cross-linked hyaluronic acid (CLHA) in an experimental model of vestibulotoxicity and cochleotoxicity.

Methods

Twenty-eight female Wistar albino rats (200-250 g) were divided into four groups. Group A received 0.06 mL of 13.33 mg/mL gentamicin, Group B received 0.06 mL of CLHA, Group C received 0.03 mL of 26.66 mg/mL gentamicin and 0.03 mL CLHA, and Group D received 0.06 mL of 0.09% saline. All groups underwent auditory brainstem response testing at 4-32 kHz, signal-to-noise ratio of distortion product otoacoustic emission measurements at 1.5-8 kHz and vestibular tests on days 0,1,7,10. The rats were sacrificed, and their labyrinths were histologically assessed and scored.

Results

The hearing thresholds of Groups A and C were similar and significantly higher than those of the other groups at all frequencies, beginning from day 1. The vestibular and histological scores of Groups A and C were similar and significantly higher than those of the other groups from day 1. The audiological results, vestibular scores, and histological scores of Groups B and D were similar, except for a temporary middle ear effusion and hearing threshold shift in Group B. No significant deterioration was observed in the audiological, vestibular, and histological analyses of Groups B and D.

Conclusion

That both Group A and Group C similarly showed worsening audiological, vestibular, and histological tests suggests that CLHA did not alter the pharmacokinetics and histologic results of gentamicin.

Ophthalmic Abnormalities among Children Treated with Cochlear Implants

OBJECTIVES

To review the ocular abnormalities in children treated with cochlear implant.

MATERIALS AND METHODS

A total of 51 children (29 boys, 22 girls) who were under 18 years old, presented previously with severe to profound hearing loss, and underwent cochlear implantation surgery were included in this study prospectively. A detailed ophthalmic examination, including refraction, best corrected visual acuity, ocular motility, slit-lamp biomicroscopy, and dilated fundus examination, was performed for each patient.

RESULTS

Mean age of the patients was 80.10±38.64 (range, 18-168) months. A total of 13 (25.4%) children had at least 1 ophthalmic abnormality. The majority of the detected ophthalmic abnormalities were hyperopia and astigmatism (6 patients had hyperopia, 5 had astigmatism, and 2 had hyperopia plus astigmatism). Strabismus (esotropia) was found in 2 patients, 2 patients had refractive amblyopia, and 2 patients had nystagmus. Moreover, 3 patients had microcornea, 2 patients had cataract, and 1 patient had epiblepharon. Optic disc coloboma (3 patients), choroidal coloboma (1 patient), and pigmentary abnormality (1 patient) were noticed on fundus examination. Congenital rubella syndrome (2 patients), Waardenburg's syndrome (1 patient), and CHARGE syndrome (coloboma, heart defects, choanal atresia, growth retardation, genital abnormalities, ear abnormalities) (1 patient) were also present.

CONCLUSION

Children treated with cochlear implant should be consulted with an ophthalmologist to identify any treatable ocular abnormality.

Selective Bilateral Vestibular Neuropathy in a Turkish CMT1B Family With a Novel MPZ Mutation

PURPOSE OF REVIEW

To report the findings in 12 members over 3 generations of a family with dominantly inherited Charcot-Marie-Tooth disease (CMT1B) due to a novel MPZ mutation, who all had moderately severe selective impairment of vestibular function with normal hearing. Methods used were video head impulse testing of the function of all 6 semicircular canals, Romberg test on foam, nerve conduction studies, and whole exome and Sanger sequencing.

RECENT FINDINGS

All affected patients had a demyelinating neuropathy and a novel MPZ mutation: c.362A>G (chr1: 161276584, p.D121G). All also had normal hearing for age but a moderately severe impairment of semicircular canal function and a positive Romberg test on foam.

SUMMARY

Some CMT mutations can impair vestibular function, presumably because of a vestibular nerve involvement but spare hearing. In such patients, impairment of vestibular function and impairment of proprioception contribute to imbalance.

Central Auditory Changes Associated with Age-related Hearing Loss

Objective. This study aimed to investigate age-related changes in cortical auditory evoked potentials (CAEPs) while considering three crucial factors: aging, high-frequency hearing loss and sensation level of the CAEP stimulus. Method. The electrophysiological and audiometric data of 71 elderly participants were analyzed using multiple regression analysis to investigate the association of CAEPs with the factors of aging, high-frequency hearing loss and sensation level of the CAEP test stimulus. Results. Aging was significantly associated with prolonged N1 and P2 latencies and reduced P2 amplitude. Elevated thresholds related to the sensation level of the CAEP stimulus were significantly associated with increased N1 and P2 amplitudes and decreased N1 latency. A significant relationship was detected between high-frequency hearing thresholds and the shortening of P2 latencies and the reduction of P2 amplitudes. Conclusion. The results of this study highlight the complex interplay of aging, high-frequency hearing loss and the sensation level of the CAEP stimulus on CAEP components in elderly people. These factors should be considered in future research using CAEPs to enhance overall understanding of auditory processing in the aging population.