Frailty and visual, auditory, olfactory, and taste senses in older patients visiting a frailty outpatient clinic

AIM

Although studies have analyzed the relationship between frailty and human senses, few have comprehensively evaluated and examined their correlations. This study aimed to clarify the relationship between frailty and the senses of sight, hearing, smell, and taste.

METHODS

The subjects were outpatients at the Locomo Frail Outpatient Clinic. Sensory organ items were evaluated subjectively, and frailty was classified as nonfrail or frail using the Kihon Checklist. Univariate analysis was performed using the presence or absence of frailty as the dependent variable. Logistic regression analysis (forced entry method) was performed for the variables that showed significant differences.

RESULTS

A total of 269 and 226 participants were assigned to the nonfrail and frail groups, respectively. The frequency of sensory organ impairment was 10.1% for taste, 12.7% for smell, 44.6% for vision, and 58.3% for hearing. Univariate analysis using the presence or absence of frailty as the dependent variable was determined to be significant for years of education, number of medications, Geriatric Depression Scale, Mini-Mental State Examination, Mini Nutritional Assessment-Short Form, grip strength, gait speed, sense of taste, sense of smell, sense of vision, and sense of hearing. Logistic regression analysis using the presence or absence of frailty as the dependent variable, adjusted for age, showed significant correlations with the Geriatric Depression Scale, gait speed, Mini Nutritional Assessment-Short Form, and olfactory impairment.

CONCLUSIONS

Olfactory impairment had the strongest correlation with frailty. Although the sense of smell decreases with disease and aging, olfactory impairment may be correlated with frailty as a symptom of neurodegenerative diseases. Geriatr Gerontol Int 2023; 23: 871-876.

The association of food intake on the development of hearing impairment after middle age among Japanese community dwellers

OBJECTIVES

This study aimed to determine whether food intake modifies the risk of developing hearing impairment (HI) in Japanese adults in their 40s.

METHODS

Data for individuals who were in their 40s with no HI at baseline and had participated in the survey multiple times were extracted from the National Institute for Longevity Sciences, Longitudinal Study of Aging. A total of 1846 samples observed for up to 11.5 years in 421 participants were included in the analyses. The average 3-day food intake was calculated. HI is defined as a pure-tone average of the better ear at frequencies of 0.5, 1, 2, and 4 kHz greater than 25 dB. The risk of developing HI in the 18 food groups was calculated longitudinally using multivariable cumulative data analyses.

RESULTS

Even after adjusting basic confounding factors, food groups, and baseline hearing level, significant associations were found between beverage consumption and risk increments for HI (odds ratio [OR] = 2.374, 95% confidence interval [CI]:1.141-4.940) and also between mushroom intake and risk reduction (OR = 0.215, 95% CI:0.069-0.667). Other foods did not consistently show significant results when the combination of analysis variables were changed.

CONCLUSIONS

Although the effect of food on hearing is modest to the extent that the significance varies with the variables used in the analysis, the intake of beverages and mushrooms could potentially modify the risk of developing HI after middle age.

Relationship between tinnitus and olfactory dysfunction: audiovisual, olfactory, and medical examinations

Introduction

Sensory dysfunctions and cognitive impairments are related to each other. Although a relationship between tinnitus and subjective olfactory dysfunction has been reported, there have been no reports investigating the relationship between tinnitus and olfactory test results.

Methods

To investigate the relationship between tinnitus and olfactory test results, we conducted sensory tests, including hearing and visual examinations. The subjects included 510 community-dwelling individuals (295 women and 215 men) who attended a health checkup in Yakumo, Japan. The age of the subjects ranged from 40 to 91 years (mean ± standard deviation, 63.8 ± 9.9 years). The participants completed a self-reported questionnaire on subjective tinnitus, olfactory function, and hearing function, as well as their lifestyle. The health checkup included smell, hearing, vision, and blood examinations.

Results

After adjusting for age and sex, the presence of tinnitus was significantly associated with subjective olfactory dysfunction, poor olfactory test results, hearing deterioration, vertigo, and headache. Additionally, high serum calcium levels and a low albumin/globulin ratio were significantly associated with low physical activity and nutrition. Women scored higher than men in olfactory and hearing examinations, but there was no gender difference in vision examinations.

Conclusion

Subjective smell dysfunction and poor smell test results were significantly associated with tinnitus complaints. Hearing and vision were associated even after adjusting for age and sex. These findings suggest that evaluating the mutual relationships among sensory organs is important when evaluating the influence of sensory dysfunctions on cognitive function.

Relationship between cognitive domains and hearing ability in memory clinic patients: How did the relationship change after 6 months of introducing a hearing aid?

OBJECTIVE

We aimed to evaluate the relationship between hearing ability and cognitive domains and determine how the relationship changes after 6 months of introducing a hearing aid.

METHODS

We conducted a 6-month hearing aid lending study between September 2014 and March 2019, including 59 older participants who visited the Memory Clinic at the National Center for Geriatrics and Gerontology. The hearing level was assessed using pure tone audiometry. Speech intelligibility was measured using the monosyllabic word discrimination score. We assessed the relationship between hearing ability and cognitive domains using the Mini-Mental State Examination (MMSE) total score and four subscale scores (orientation, memory, attention, and language). Differences in the cognitive function between baseline (pre-) and 6 months later (post-) after introducing a hearing aid were also assessed.

RESULTS

The pre-orientation score was significantly associated with the pure-tone average (p = 0.013), and the pre-language score was significantly associated with speech intelligibility (p = 0.006) after adjusting for confounders. None of the MMSE subscale scores were significantly different between pre- and post-scores, however, an expectation of improvement with continuous hearing aid use was implied in the attention domain.

CONCLUSION

We found a significant association between hearing ability and cognitive domains in individuals whose cognitive functions were not considered healthy. The presence of a potential relationship between cognitive domains, hearing ability, and auditory compensation is suggested.

Cognitive impairment is correlated with olfactory identification deficits in older Japanese adults: A cross-sectional study using objective and subjective olfactory measures

AIM

Olfactory impairment is associated with cognitive impairment. However, differences between subjective and objective olfactory impairment measurements in older adults and their relationship with cognitive impairment are unclear.

METHODS

We assessed the relationship between cognitive and olfactory impairments via a single-center observational study in 2020. Forty-seven individuals who visited our memory clinic were enrolled and asked to complete objective and subjective olfactory tests. Participants had dementia, mild cognitive impairment, or normal cognition. We administered the Open Essence (a simple card-type odor identification test) and self-administered odor questionnaire to assess objective and subjective olfaction, respectively, and the Mini-Mental State Examination to assess cognitive function.

RESULTS

Older age was related to decreased Open Essence scores (P < 0.001). Compared with the mild cognitive impairment and normal cognition groups, the dementia group had significantly lower Open Essence scores (P < 0.001). Cognitive impairment was also associated with decreased Open Essence scores after adjusting for age, sex, and education (P < 0.001). Participants with dementia did not obtain lower self-administered odor questionnaire scores than those with normal cognition, and they tended to be unaware of their olfactory impairment.

CONCLUSION

Open Essence scores significantly decreased according to the degree of cognitive impairment. Participants with dementia were unaware of their olfactory impairment, as indicated by odor questionnaire scores. Objective and subjective scores of olfaction differed in participants with dementia. Concomitant assessment of objective and subjective olfaction is useful to screen older adults with both olfactory and cognitive impairments. Geriatr Gerontol Int ••; ••: ••-•• Geriatr Gerontol Int 2022; ••: ••-••.

Aging Brain and Hearing: A Mini-Review

Brain reserve is a topic of great interest to researchers in aging medicine field. Some individuals retain well-preserved cognitive function until they fulfill their lives despite significant brain pathology. One concept that explains this paradox is the reserve hypothesis, including brain reserve that assumes a virtual ability to mitigate the effects of neuropathological changes and reduce the effects on clinical symptoms flexibly and efficiently by making complete use of the cognitive and compensatory processes. One of the surrogate measures of reserve capacity is brain volume. Evidence that dementia and hearing loss are interrelated has been steadily accumulating, and age-related hearing loss is one of the most promising modifiable risk factors of dementia. Research focused on the imaging analysis of the aged brain relative to auditory function has been gradually increasing. Several morphological studies have been conducted to understand the relationship between hearing loss and brain volume. In this mini review, we provide a brief overview of the concept of brain reserve, followed by a small review of studies addressing brain morphology and hearing loss/hearing compensation, including the findings obtained from our previous study that hearing loss after middle age could affect hippocampal and primary auditory cortex atrophy.

Longitudinal associations between hearing aid usage and cognition in community-dwelling Japanese older adults with moderate hearing loss

We investigated the associations between hearing aids (HA) and the maintenance of cognitive function among community-dwelling older adults with moderate hearing loss. A total of 407 participants aged 60 years or older with moderate hearing loss were recruited from the National Institute for Longevity Sciences, Longitudinal Study for Aging (NILS-LSA). Moderate hearing loss was defined as a pure-tone average of 40–69 dB at 500, 1000, 2000, and 4000 Hz of the better ear, according to the definition proposed by the Japan Audiological Society. Cognitive function was evaluated using the four subtests of the Japanese version of the Wechsler Adult Intelligence Scale-Revised Short Forms (WAIS-R-SF): Information, Similarities, Picture completion, and Digit Symbol Substitution (DSST). A longitudinal analysis of 1192 observations with a mean follow-up period of 4.5 ± 3.9 years was performed. The HA use rate at any time during the follow-up period was 31.4%, and HA users were significantly younger (t-test, p = 0.001), had worse hearing (p < .0001) and higher education (p = 0.001), participated more frequently in the survey (p < .0001), and were less depressed (χ² test, p = 0.003) than the older adults not using HA. General linear mixed models consisted of the fixed effects of HA use, follow-up time, and an HA use × time interaction term adjusted for age and pure-tone average thresholds at baseline, sex, education, and other possible confounders. HA use showed significant main effects on the scores for Picture completion and DSST after adjustment; scores were better in the HA use group than in the no HA use group. The HA use × time interaction was significant for the Information score (p = 0.040). The model-predicted 12-year slope with centralizing age indicated that the no HA use group showed greater decline over time on Information scores than did HA use group. The slopes did not differ between HA users and non-users for the Similarities, Picture completion and DSST. In conclusion, HA use may have a protective effect on the decline in general knowledge in older adults with moderate hearing loss.

Prevalence of usage of hearing aids and its association with cognitive impairment in Japanese community-dwelling elders with hearing loss

OBJECTIVE

Hearing loss is a risk factor for cognitive impairment, and the use of a hearing aid (HA) may prevent cognitive decline alongside hearing loss. We aimed to elucidate the prevalence of self-reported HA usage in Japanese community-dwelling elders with hearing loss, and the effect of hearing and HA on cognitive impairment.

METHODS

A total of 1193 participants, who had audiometric defined hearing loss and were aged 60 years or over, had their cumulative 3260 observations followed up for 10 years from a large cohort of a Japanese study. Association between hearing (pure-tone average threshold level at 500, 1000, 2000, and 4000 Hz from the better hearing ear: PTABHE) and HA usage with cognitive impairment (total score of Mini-Mental State Estimation was under 27 or diagnosed as dementia) was analyzed using generalized estimating equations.

RESULTS

The HA usage rate of the 1193 community-dwelling elders with hearing loss was 6% during the first involvement. The majority (59.2%) of HA users always used an HA. HA usage rate was 0.7% for the mild hearing loss group and 32.4% for the moderate or greater hearing loss group in the latest participating wave. PTABHE was significantly associated with cognitive impairment (odds ratio for every 10 dB 1.36; 95% CI 1.21-1.53, p<0.0001) after adjusting for age, sex, education, depressed mood, smoking status, alcohol intake, income, activity, obesity, histories of hypertension, dyslipidemia, ischemic heart disease, diabetes, stroke, ear disease, and occupational noise exposure. PTABHE was also significantly associated with cognitive impairment in the mild hearing loss group (odds ratio for every 10 dB 1.34; 95% CI 1.05-1.72, p = 0.020) and moderate hearing loss group (odds ratio for every 10 dB 1.82; 95% CI 1.27-2.61, p = 0.001). HA use showed a significant suppressive effect on cognitive impairment in those with moderate hearing loss who always use an HA (odds ratio 0.54; 95% CI 0.30-1.00, p = 0.049).

CONCLUSION

The prevalence of HA usage among Japanese community-dwelling elders with hearing loss is consistent, at around 10%. The hearing level remained a primary risk factor for cognitive impairment among elders with hearing loss after adjusting for several confounding factors. Regular HA use may have a protective effect on cognitive impairment in those with moderate hearing loss.

Gustatory function in persons with cerebral palsy

Gustatory function is closely related to chewing and swallowing; however, there are currently no reports regarding gustatory function in persons with cerebral palsy (CP). The aim of this study was to compare the gustatory function between persons with CP and healthy controls. We investigated sweet, salty, sour and bitter tastes using the whole-mouth method and measured the electrogustometric thresholds in the chorda tympani nerve area. Twelve participants with CP (6 women and 6 men) for whom gustatory testing was possible at our facilities, and 17 age-matched controls (9 women and 8 men) were included. The mean age ± standard deviation was 58.6 ± 8.1 years and 58.5 ± 8.7 years in subjects with CP and controls, respectively. Taste detection and identification were significantly worse in persons with CP compared with the controls. Taste identification was more impaired than taste detection. At the highest concentration, taste identification was impossible 11 times out of 48 (12 persons × 4 kinds of tastes) in persons with CP but such a deficit was not observed in 68 attempts (17 persons × 4 kinds of tastes) involving controls. The electrogustometric thresholds were not significantly different between the groups. Gustatory function associated with chewing and swallowing is worse in persons with CP compared to the controls.

Association between Uncoupling Protein 2 Gene Ala55val Polymorphism and Sudden Sensorineural Hearing Loss

OBJECTIVES

The pathology of sudden sensorineural hearing loss, which is known as sudden deafness (SD), remains unknown. The purpose of this study was to investigate the association between mitochondrial uncoupling protein 2 (UCP2) polymorphism and SD risk.

MATERIALS AND METHODS

We compared 83 patients suffering from SD and 2048 controls who participated in the Longitudinal Study of Aging at the National Institute for Longevity Sciences. Multiple logistic regression was used to calculate the odds ratios (ORs) for SD with a polymorphism of the UCP2 (rs660339) gene.

RESULTS

Under the additive model of inheritance, UCP2 polymorphisms showed significant association with a SD risk. The OR was 1.468 (95% confidence interval, 1.056-2.040) with an adjustment for any past history, such as diabetes, dyslipidemia, or hypertension, and for age and sex.

CONCLUSION

Our results imply that the UCP2 (rs660339) polymorphism has a significant association with the risk of developing SD.

Difference in Serum Levels of Vitamin D Between Canalolithiasis and Cupulolithiasis of the Horizontal Semicircular Canal in Benign Paroxysmal Positional Vertigo

Background and Purpose: In the horizontal canal benign paroxysmal positional vertigo (BPPV), cupulolithiasis shows apogeotropic direction changing nystagmus lasting more than 1 min, while canalolithiasis leads to geotropic direction changing nystagmus lasting < 1 min. The difference between cupulolithiasis and canalolithiasis is widely accepted to be the attachment of the displaced otoconia to the cupula of a semicircular canal. Several studies have shown a relationship between BPPV and vitamin D deficiency, but no studies have compared serum levels of vitamin D between canalolithiasis and cupulolithiasis patients. The purpose of this study was to clarify the difference in vitamin D serum level between canalolithiasis and cupulolithiasis of the horizontal canal.

Methods: This retrospective study included 20 and 15 patients with canalolithiasis and cupulolithiasis of the horizontal canal, respectively. Serum levels of 25-hydroxyvitamin D [25(OH)D] during the acute phase of BPPV were measured.

Results: The mean 25(OH)D serum level in patients with canalolithiasis and cupulolithiasis was 13.2 ± 1.4 and 20.4 ± 1.6 ng/mL, respectively, and the difference was statistically significant (p = 0.0014), also after adjusting for age and sex (p = 0.0351). Eighteen out of 20 (90%) and 5 of 15 (33%) patients were diagnosed with vitamin D deficiency in the canalolithiasis and cupulolithiasis groups, respectively, and this difference was also statistically significant (p = 0.0005).

Conclusion: We found that serum vitamin D level in patients with canalolithiasis was significantly lower than that in patients with cupulolithiasis of the horizontal canal.

Smaller Hippocampal Volume and Degraded Peripheral Hearing Among Japanese Community Dwellers

A growing body of literature has demonstrated that dementia and hearing loss are interrelated. Recent interest in dementia research has expanded to brain imaging analyses with auditory function. The aim of this study was to investigate the link between hearing ability, which was assessed using pure-tone audiometry, and the volume of brain regions, specifically the hippocampus, entorhinal cortex, Heschl's gyrus, and total gray matter, using Freesurfer software and T1-weighted brain magnetic resonance imaging. The data for 2082 samples (age range = 40-89 years) were extracted from a population-based cohort of community dwellers. Hearing-impaired individuals showed significantly smaller hippocampal volumes compared with their non-hearing-impaired counterparts for all auditory frequency ranges. In addition, a correlational analysis showed a significant dose-response relationship for hearing ability and hippocampal volume after adjusting for potential confounding factors so that the more degraded the peripheral hearing was, the smaller the hippocampal volume was. This association was consistent through the auditory frequency range. The volume of the entorhinal cortex, right Heschl's gyrus and total gray matter did not correlate with hearing level at any frequency. The volume of the left Heschl's gyrus showed a significant relationship with the hearing levels for some auditory frequencies. The current results suggested that the presence of hearing loss after middle age could be a modifier of hippocampal atrophy.

Evaluation of serum IgE in peach-allergic patients with systemic reaction by using recombinant Pru p 7 (gibberellin-regulated protein)

BACKGROUND

Lipid transfer protein (LTP) is a major fruit allergen. It has, however, recently been revealed that the systemic reaction in peach-allergic patients is related not only to LTP (Pru p 3) but also to gibberellin-regulated protein (Pru p 7). We investigated recombinant Pru p 7 (rPru p 7) for its potential use in worldwide standardization for the diagnosis of peach allergy.

METHODS

Natural Pru p 7 (nPru p 7) was purified from peach crude extract using a monoclonal antibody affinity column. Complementary DNA for Pru p 7 was cloned and expressed in Escherichia coli and Pichia pastoris. Serum immunoglobulin (Ig) E in peach-allergic patients was examined by enzyme-linked immunosorbent assay (ELISA) using nPru p 7 and rPru p 7 (E. coli product: erPru p 7 and P. pastoris product: prPru p 7).

RESULTS

Peach-allergic patients (n=27) were diagnosed and categorized into oral reaction (n=10) or systemic reaction (n=17). The nPru p 7 positivity based on serum IgE levels was 52% in the systemic-reaction group and 0% in the oral-reaction group (P<0.05). In the systemic-reaction group, there was no significant difference in reactivity between nPru p 7 and prPru p 7, but the reactivity of erPru p 7 was significantly lower than those of nPru p 7 and prPru p 7 (P<0.05).

CONCLUSIONS

We found that prPru p 7 exhibited reactivity in ELISA comparable to that of nPru p 7 for the diagnosis of peach allergy with systemic reaction.

A multi-throughput multi-organ-on-a-chip system on a plate formatted pneumatic pressure-driven medium circulation platform

This paper reports a multi-throughput multi-organ-on-a-chip system formed on a pneumatic pressure-driven medium circulation platform with a microplate-sized format as a novel type of microphysiological system. The pneumatic pressure-driven platform enabled parallelized multi-organ experiments (i.e. simultaneous operation of multiple multi-organ culture units) and pipette-friendly liquid handling for various conventional cell culture experiments, including cell seeding, medium change, live/dead staining, cell growth analysis, gene expression analysis of collected cells, and liquid chromatography-mass spectrometry analysis of chemical compounds in the culture medium. An eight-throughput two-organ system and a four-throughput four-organ system were constructed on a common platform, with different microfluidic plates. The two-organ system, composed of liver and cancer models, was used to demonstrate the effect of an anticancer prodrug, capecitabine (CAP), whose metabolite 5-fluorouracil (5-FU) after metabolism by HepaRG hepatic cells inhibited the proliferation of HCT-116 cancer cells. The four-organ system, composed of intestine, liver, cancer, and connective tissue models, was used to demonstrate evaluation of the effects of 5-FU and two prodrugs of 5-FU (CAP and tegafur) on multiple organ models, including cancer and connective tissue.

PTPRQ as a potential biomarker for idiopathic normal pressure hydrocephalus

Idiopathic normal pressure hydrocephalus (iNPH) is caused by the accumulation of cerebrospinal fluid (CSF) and is characterized by gait disturbance, urinary incontinence, and dementia. iNPH dementia is treatable by shunt operation; however, since the cognitive symptoms of iNPH are often similar to those of other dementias, including Alzheimer's disease (AD), accurate diagnosis of iNPH is difficult. To overcome this problem, the identification of novel diagnostic markers to distinguish iNPH and AD is warranted. Using comparative proteomic analysis of CSF from patients with iNPH and AD, protein tyrosine phosphatase receptor type Q (PTPRQ) was identified as a candidate biomarker protein for discriminating iNPH from AD. ELISA analysis indicated that the PTPRQ concentration in the CSF was significantly higher in patients with iNPH compared with those with AD. In addition, the PTPRQ concentration in the CSF of non‑responders to shunt operation (SNRs) tended to be relatively lower compared with that in the responders. PTPRQ may be a useful biomarker for discriminating between patients with iNPH and AD, and may be a potential companion biomarker to identify SNRs among patients with iNPH. Additional large‑scale analysis may aid in understanding the novel aspects of iNPH.

Endolymphatic hydrops in patients with unilateral and bilateral Meniere's disease

CONCLUSION

All definite Meniere's disease (MD) had endolymphatic hydrops (EH) at least in the cochlea or the vestibule. Symptoms of MD may appear after formation of EH. It is assumed that the probability of immediate progression to bilateral MD from unilateral MD is very low in patients without EH on the non-affected side.

OBJECTIVE

To evaluate the EH on both sides in patients with unilateral and bilateral MD, and to investigate factors with progression to bilateral MD including the degree of EH, hearing level, and the duration of MD.

PATIENTS AND METHODS

The study included 29 patients with unilateral definite MD and 12 patients with bilateral definite MD. The endolymphatic space size was visualized by using 3-Tesla magnetic resonance imaging.

RESULTS

All patients with unilateral and bilateral MD had significant or mild EH at least in the cochlea or the vestibule on the affected side. On the non-affected side, EH was not observed at all in eight patients, but asymptomatic EH was observed in the cochlea in 14 patients and in the vestibule in 16 patients. There was no relationship between the EH on the non-affected side and the duration of MD.

Prevalence of Sinusitis Detected by Magnetic Resonance Imaging in Subjects with Dementia or Alzheimer's Disease

BACKGROUND

It has been reported that periodontitis is associated with Alzheimer's disease. However, the association between paranasal sinusitis and Alzheimer's disease has not been studied, although olfactory dysfunction frequently precedes the progress of dementia or Alzheimer's disease.

METHODS

We studied 783 patients (283 men, 500 women; mean age 77.0 ± 7.9 years) who visited the Center for Comprehensive Care and Research on Memory Disorders, National Center for Geriatrics and Gerontology, and 2139 control subjects who participated in a population-based study conducted by the National Institute for Longevity Sciences - Longitudinal Study of Aging (NILS-LSA) in Japan. Sinusitis was evaluated using magnetic resonance imaging (MRI) according to the Lund-Mackay scoring system. A sinusitis score of ≥ 4 was classified as positive and a score of ≤ 3 was classified as negative.

RESULTS

The prevalence of positive sinusitis was 6.3% in patients with a mini-mental state examination (MMSE) score of < 24 (n = 507), and 5.7% in patients with Alzheimer's disease (n = 280). The rate of positive sinusitis was7.2% in the control group. The prevalence of sinusitis was not significantly different between normal controls and patients with dementia or Alzheimer's disease after adjustments for age and sex. The rate of positive sinusitis was higher in male than in female subjects in both groups.

CONCLUSION

The prevalence of sinusitis in patients with Alzheimer's disease or dementia was not higher than in the general population.

The Longitudinal Impact of Hearing Impairment on Cognition Differs According to Cognitive Domain

Identification and modification of the risk factors for cognitive decline throughout the adult life span are priority subjects in a progressively aging society; however, much remains to be learned. The aim of this study was to understand whether changes in cognitive function can be affected by hearing impairment (HI) and whether the impact of HI differs depending on the cognitive domain. A total of 1109 individuals aged 60-79 years at baseline who participated in the Longitudinal Study of Aging at the National Institute for Longevity Sciences (NILS-LSA) was followed up for a maximum of 13.3 years. Cognitive function was evaluated using four subtests of the Japanese Wechsler Adult Intelligence Scale-Revised Short Forms (JWAIS-R-SF): namely, Information, Similarities, Picture Completion, and the Digit Symbol Substitution subtests. The HI was defined as a pure-tone average of the better ear >25 dB. A longitudinal analysis of 4437 observations obtained during a follow-up period of approximately 12 years was performed. We estimated linear changes in subtest scores by HI status, using the time-varying mixed-effects regression model, which included fixed terms for the intercept, HI status at baseline, time (years elapsed since baseline) and an HI × time interaction term adjusted for age at baseline, sex, education, and other possible confounders. There were significant main effects of HI on the scores of the four subtests after adjustment. The HI × time interaction was significant for the scores of the Information (p = 0.001) and Digit Symbol Substitution subtests (p = 0.001). The scores of the HI group declined faster in the Information and Digit Symbol Substitution subtests compared to those in the no-HI group. The model-predicted 12-year slope using a mean baseline age (68.7 years) indicated no significant decline in the individuals without HI at baseline for the Information and Similarities subtests, however, this tolerance was lost in the individuals with HI. In conclusion, the present observation showed that the impact of HI on cognition was longitudinally significant and implied that the effect differs according to cognitive domain.

A pneumatic pressure-driven multi-throughput microfluidic circulation culture system

Here, we report a pneumatic pressure-driven microfluidic device capable of multi-throughput medium circulation culture. The circulation culture system has the following advantages for application in drug discovery: (i) simultaneous operation of multiple circulation units, (ii) use of a small amount of circulating medium (3.5 mL), (iii) pipette-friendly liquid handling, and (iv) a detachable interface with pneumatic pressure lines via sterile air-vent filters. The microfluidic device contains three independent circulation culture units, in which human umbilical vein endothelial cells (HUVECs) were cultured under physiological shear stress induced by circulation of the medium. Circulation of the medium in the three culture units was generated by programmed sequentially applied pressure from two pressure-control lines. HUVECs cultured in the microfluidic device were aligned under a one-way circulating flow with a shear stress of 10 dyn cm(-2); they exhibited a randomly ordered alignment under no shear stress and under reciprocating flow with a shear stress of 10 dyn cm(-2). We also observed 2.8- to 4.9-fold increases in expression of the mRNAs of endothelial nitric oxide synthase and thrombomodulin under one-way circulating flow with a shear stress of 10 dyn cm(-2) compared with conditions of no shear stress or reciprocating flow.

Changes in endolymphatic hydrops in patients with Ménière's disease treated conservatively for more than 1 year

CONCLUSION

This study revealed that endolymphatic hydrops (EH) reduced in some cases with Ménière's disease (MD) treated conservatively. It appears that the EH reduction was associated with improvement of the clinical symptoms.

OBJECTIVES

The relationship between the degree of EH and clinical symptoms is not clear at present. The purpose of the present study was to investigate the time course of the relationship in patients with MD treated conservatively.

PATIENTS

Twelve patients with MD treated conservatively for more than 1 year in a university hospital.

METHODS

Twenty ears of 12 patients with MD treated conservatively were evaluated. The presence or absence of vertigo, tinnitus and ear fullness was confirmed when magnetic resonance imaging (MRI) was performed. Using a 3 T MRI scanner, three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) MRI was performed 2 or 3 times 24 hours after intra-tympanic gadolinium injection or 4 hours after intravenous gadolinium injection.

RESULTS

In the three ears in which the symptoms alleviated, EH was reduced in two ears, but EH was reduced in only one of 17 ears in which the symptoms did not alleviate. The Fisher exact test revealed that EH reduction occurred more frequently in ears with alleviation of the symptoms (p < 0.05).

The human ether-a-go-go-related gene (hERG) current inhibition selectively prolongs action potential of midmyocardial cells to augment transmural dispersion

The majority of drug induced arrhythmias are related to the prolongation of action potential duration following inhibition of rapidly activating delayed rectifier potassium current (I(Kr)) mediated by the hERG channel. However, for arrhythmias to develop and be sustained, not only the prolongation of action potential duration but also its transmural dispersion are required. Herein, we evaluated the effect of hERG inhibition on transmural dispersion of action potential duration using the action potential clamp technique that combined an in silico myocyte model with the actual I(Kr) measurement. Whole cell I(Kr) current was measured in Chinese hamster ovary cells stably expressing the hERG channel. The measured current was coupled with models of ventricular endocardial, M-, and epicardial cells to calculate the action potentials. Action potentials were evaluated under control condition and in the presence of 1, 10, or 100 μM disopyramide, an hERG inhibitor. Disopyramide dose-dependently increased the action potential durations of the three cell types. However, action potential duration of M-cells increased disproportionately at higher doses, and was significantly different from that of epicardial and endocardial cells (dispersion of repolarization). By contrast, the effects of disopyramide on peak I(Kr) and instantaneous current-voltage relation were similar in all cell types. Simulation study suggested that the reduced repolarization reserve of M-cell with smaller amount of slowly activating delayed rectifier potassium current levels off at longer action potential duration to make such differences. The action potential clamp technique is useful for studying the mechanism of arrhythmogenesis by hERG inhibition through the transmural dispersion of repolarization.

Cerumen impaction shown by brain magnetic resonance imaging in patients with cognitive impairment

AIM

Hearing loss is a risk factor for the progression of dementia. Cognitive improvement is occasionally found after removal of cerumen impaction. Because patients with dementia do not usually complain about cerumen impaction, detection methods are important. The present study aimed to investigate whether cerumen impaction is observable using brain magnetic resonance imaging.

METHODS

Participants were six patients whose hearing level improved 15 dB or more unilaterally or bilaterally after the removal of cerumen impaction. A radiologist who was blind to the impaction side and whether magnetic resonance imaging scans were taken before or after impaction removal classified cerumen impaction as positive, negative or unclear.

RESULTS

Three ears classified as impaction positive and five ears classified as impaction negative corresponded accurately to the presence or absence of cerumen impaction. Among four ears classified as unclear, two did and two did not have cerumen impaction.

CONCLUSION

Careful examination of the external ear canal on brain magnetic resonance imaging can be used to detect cerumen impaction.

The association between hearing impairment and polymorphisms of genes encoding inflammatory mediators in Japanese aged population

BACKGROUND

Aging process is accompanied by a chronic sub-clinical systemic inflammation. This study aimed to assess the association between hearing impairment and polymorphisms of genes encoding cytokines deeply-committed to the inflammatory response and immune homeostasis in an elderly Japanese population. Data were collected in the Longitudinal Study of Aging surveyed biennially between 1997 and 2010. The participants without any missing information at baseline were 1,957 individuals, and the gross accumulated number of 8,675 subjects (40-89 years of age) was analyzed. Two hearing impairment criteria were taken as the better ear pure-tone average (PTABE) greater than 25 dB and greater than 40 dB. We analyzed cumulative data using generalized estimating equations to investigate the effect of 9 polymorphisms, namely, tumor necrosis factor (TNF) α, rs1800630; TNF receptor super family (TNFRSF) 1B, rs1061624; interleukin (IL)-1A, rs1800587; IL-1B, rs16944; IL-4R, rs1801275; IL-6, rs1800796; IL-10, rs1800872; IL-1 receptor-associated kinase 1 (IRAK1), rs1059702; C reactive protein (CRP), rs1130864.

RESULTS

The odds ratios for the hearing impairment (PTABE >25 dB) risk under additive genetic model were significant in TNF-α rs1800630 and TNFRSF1B rs1061624, which were respectively 1.172 (confidence interval [CI]: 1.005-1.367), 1.211 (CI: 1.053-1.392) in model after adjustment for possible confounders. Using the criterion of PTABE >40 dB as disabling hearing impairment, the association remains significant in TNFRSF1B rs1061624, but not in TNF-α rs1800630. No other polymorphisms showed a significant association.

CONCLUSIONS

The present population-based cohort study demonstrated that TNF-α rs1800630 and TNFRSF1B rs1061624 contributed to the incremental risk of hearing impairment in the elderly. TNF-α and TNF receptor interactions play a pivotal role in the pathogenesis of the inflammatory response, and also cause programmed cell death and cell proliferation. The present observation implied the signalling cascades of TNF were involved in ear aging.

[Decline of speech understanding in the hearing impaired elderly listeners who visited our hearing aid clinic]

The aim of this study was to investigate distinctive change in the hearing impaired elderly listeners, especially about speech recognition. Subjects were 525 patients (235 males, 290 females), from 60 to 98 years of age who had visited the Hearing Aid Clinic of Otorhinolaryngology, National Center for Geriatrics and Gerontology Hospital, between June 2001 and December 2012. Pure-tone air conduction threshold determination was administered to each subject. The speech audiometry materials used to define speech discrimination ability were Japanese monosyllabic word lists, 67S word lists. Sex- and age-specific trends in maximum discrimination score (MDS) and rollover index (RI) were shown in this study. RI was computed by the formula (PBmax-PBmin)/PBmax. PBmax has almost the same meaning as MDS in Japan. PBmin represented the lowest PB score above the test intensity level of PBmax. Mean MDSs were 80.8% in their sixties, 75.3% in their seventies, 60.7% in their eighties, and 45.5% in their nineties. The rate of decrease in mean MDS per decade accelerated in the older generation. Mean RIs were 0.18 in patients in their sixties, 0.24 in their seventies, 0.30 in their eighties, and 0.30 in their nineties. It increased until the age of eighties. In the model 1, multiple logistic analyses were performed to examine the effect of age (in 10-year increments), sex and mean hearing levels in pure tone average of values at 500, 1000, 2000, 4000 Hz (in 10 dB increments) on the MDS < 60%. Significant associations were observed between MDS < 60% and age (odds ratio, 3.03; 95% confidence interval, 2.38 to 3.85), and mean hearing levels in pure tone average of values at 500, 1000, 2000, 4000 Hz (2.33; 2.03 to 2.68). Sex was not associated with MDS < 60%. In the model 2, multiple logistic analyses adjusted for age and sex were performed to examine the effect of hearing level at test frequencies of 125, 250, 500, 1000, 2000, 4000, and 8000 Hz (in 10 dB increments)on the MDS < 60%. Significant associations were observed between MDS < 60% and hearing level at 250 Hz (2.04; 1.44 to 2.89), and 2000 Hz (1.46; 1.16 to 1.83), and 4000 Hz(1.24; 1.02 to 1.50). These outcomes suggest that the important point in qualifying the fitting of hearing aid is to present the list words at an adequate sound pressure level for evaluation of speech understanding especially in the hearing impaired elderly listeners.

Utilizing stomach content and faecal DNA analysis techniques to assess the feeding behaviour of largemouth bass Micropterus salmoides and bluegill Lepomis macrochirus

In this study, the feeding behaviour of the non-native invasive predatory fishes largemouth bass Micropterus salmoides and bluegill Lepomis macrochirus was studied in the Ezura River, a northern tributary of Lake Biwa, Japan. Prey composition was estimated based on visual examination of stomach contents and faecal DNA analysis to determine feeding habits of these predatory fishes. Stomach content analysis showed that native fishes (e.g. ayu Plecoglossus altivelis and gobies Rhinogobius spp.) and shrimps (e.g. Palaemon paucidens) were the major prey items for M. salmoides, while snails, larval Chironomidae and submerged macrophytes were the dominant prey items of L. macrochirus. Micropterus salmoides tended to select larger fish in the case of crucian carp Carassius spp., but smaller fishes in the case of P. altivelis and Rhinogobius spp. Faecal DNA analyses revealed prey compositions similar to those identified in predator stomach contents, and identified additional prey species not detected in stomach content inspection. This study demonstrated that both stomach content inspection and DNA-based analysis bear several inherent shortcomings and advantages. The former method is straightforward, although identification of species can be inaccurate or impossible, whereas the latter method allows for accurate species identification, but cannot distinguish prey size or stage. Hence, integration of morphology-based and DNA-based methods can provide more reliable estimates of foraging habits of predatory fishes.

[Estimates of the size of the hearing-impaired elderly population in Japan and 10-year incidence of hearing loss by age, based on data from the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA)]

AIM

The number of hearing-impaired elderly people in Japan remains to be clarified. In the present study, we analyzed the data from the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) to ascertain the prevalence and 10-year incidence of hearing loss in Japanese elderly people.

METHODS

Hearing loss prevalence was calculated based on 2,194 subjects who had been included in the 6th survey of the NILS-LSA (2008-2010) and was represented as crude rates (calculation A) and as rates after the exclusion of occupational noise-exposure and ear disease history (calculation B). Estimates of hearing loss incidence were performed at a national level based on demographic statistics. Subsequently, we analyzed the 10-year incidence in 465 subjects showing no hearing loss at baseline (1997-2000 survey) all of whom also participated in the 6(th) survey of the NILS-LSA (2008-2010).

RESULTS

The prevalence of hearing loss greatly increased after the age of 65 years. The prevalence observed in calculation A was 43.7%, 51.1%, 71.4%, and 84.3% in men aged 65-69, 70-74, 75-79, and over 80 years old, respectively. In women, the prevalence for the same age groups was 27.7%, 41.8%, 67.3%, and 73.3%, respectively. The size of the hearing-impaired population older than 65 years old was estimated to be 16,553,000. The 10-year incidence rates of hearing impairment in the 60-64- and 70-74-year-old age groups were 32.5% and 62.5% (age at baseline), respectively. These rates rapidly increased with age, although a number of elderly people with good hearing were also observed.

CONCLUSIONS

Age-related hearing loss is an issue of national importance. These results also indicated that it is possible to preserve good hearing into later in life, and that hearing loss in the elderly may be preventable.

Contributing factors to hearing of diabetic patients in an in-hospital education program

CONCLUSION

In patients with poorly controlled diabetes mellitus (DM), hearing disturbance was associated with renal dysfunction and diabetic neuropathy, represented by decreases in median nerve compound action potential amplitude.

METHODS

The evaluation was conducted using 43 subjects who were hospitalized for the purpose of DM education. The mean age was 58.1 years (range 21-82 years). The mean HbA1c was 9.5%. The mean DM duration was 11.0 years. Renal function, retina condition, and nerve conduction were evaluated in relation to DM complications (nephropathy, retinopathy, and neuropathy). Nerve conduction studies were used to obtain detailed information on the condition of the peripheral nerves. After otological inspection, pure-tone audiometry, auditory steady-state response (ASSR), and distortion-product otoacoustic emissions (DPOAEs) were measured. Stepwise multiple linear regression was used to analyze the results in the better ear and worse ear.

RESULTS

Decreases in median nerve compound action potential amplitude were associated with deterioration in pure-tone audiometry and ASSR. Diabetic neuropathy, creatinine clearance, diabetic nephropathy, and retinopathy were related to hearing in ASSR and/or DPOAEs.

Association between polymorphisms in genes encoding methylenetetrahydrofolate reductase and the risk of Ménière's disease

Folate metabolism is essential for cellular functioning. Despite extensive research on the roles of folate-metabolism-related gene polymorphisms in the pathophysiology of many diseases, such as cardiovascular disease, cancers, and sudden sensorineural hearing loss, little is known about their association with Ménière's disease (MD). The aim of this study was to investigate the effect of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms (C677T and A1298C) on the risk of MD in a Japanese population. We examined the C677T and A1298C (rs1801133 and rs1801131) polymorphisms in the MTHFR gene and compared them between 1946 adults (986 men and 960 women) participating in the National Institute for Longevity Sciences Longitudinal Study of Aging and 86 cases of MD. A multiple logistic regression was performed to obtain odds ratios (ORs) for the risk of MD regarding the MTHFR polymorphisms before (model 1) and after (model 2) adjustment for age and sex factors. The OR of MTHFR C677T for the risk of MD was 0.669 (95% confidence interval [CI], 0.479-0.934) in model 1 and 0.680 (95% CI, 0.484-0.954) in model 2. In contrast, the OR of MTHFR A1298C for the risk of MD was 1.503 (95% CI, 1.064-2.123) in model 1 and 1.505 (95% CI, 1.045-2.167) in model 2. Our results imply that the MTHFR C677T and A1298C polymorphisms are associated with the risk of MD.

Polymorphisms in genes involved in oxidative stress response in patients with sudden sensorineural hearing loss and Ménière's disease in a Japanese population

The etiologies of idiopathic sudden sensorineural hearing loss (SSNHL) and Ménière's disease remain unclear. Recently, accumulating evidence has demonstrated that oxidative stress is related to the pathology of inner ear disease. Because genetic factors may contribute partly to the etiologies of SSNHL and Ménière's disease, we investigated the associations between genetic polymorphisms located in oxidative stress response genes and susceptibility to SSNHL and Ménière's disease. We compared 84 patients affected by SSNHL, 82 patients affected by Ménière's disease, and 2107 adults (1056 men and 1051 women; mean age, 59.2 years; range, 40-79 years) who participated in the National Institute for Longevity Sciences, Longitudinal Study of Aging. Multiple logistic regression was used to calculate odds ratios for SSNHL and Ménière's disease in individuals with polymorphisms in the genes glutathione peroxidase 1 (GPX1) (Pro198Leu, rs1050450), paraoxonase 1 (PON1) (Gln192Arg, rs662; and Met55Leu, rs854560), PON2 (Ser311Cys, rs7493), and superoxide dismutase 2 (SOD2) (Val16Ala, rs4880), with adjustment for age and gender. No significant differences in the distribution of the genotypes at these polymorphisms were observed among individuals with SSNHL and Ménière's disease and controls. No significant risk for SSNHL and Ménière's disease was observed in the additive genetic model, regardless of moderating variables. The C allele of SOD2 (rs4880) was more frequent in Ménière's disease cases with a hearing level over 50 dB compared with cases with a hearing level below 50 dB, suggesting that this polymorphism is associated with progression of a hearing loss in Ménière's disease. In conclusion, no significant associations between the polymorphisms of GPX1, PON1, PON2, and SOD2 and risk of SSNHL and Ménière's disease were observed in this Japanese case-control study.

Contribution of complement factor H Y402H polymorphism to sudden sensorineural hearing loss risk and possible interaction with diabetes

Sudden sensorineural hearing loss (SSNHL) is one of the most common diseases encountered by otolaryngologists; however, the etiology is unclear. The aim of this study was to assess the association between SSNHL and polymorphism of complement factor H (CFH) Y402H, which is implicated in age-related macular degeneration. We conducted a case-control study, in which the cases were 72 SSNHL patients and the controls were 2161 residents selected randomly from the resident register. The odds ratio (OR) for SSNHL risk was determined using the additive-genetic model of CFH Y402H polymorphism. The OR for SSNHL risk was 1.788 (95% confidence interval [CI]: 1.008-3.172) with no adjustments and 1.820 (CI: 1.025-3.232) after adjusting for age and sex. Of the three lifestyle-related diseases hypertension, dyslipidemia, and diabetes, only diabetes was significantly associated with SSNHL risk. We classified both the controls and SSNHL patients into those with or without diabetes, and the OR for SSNHL risk was 6.326 (CI: 1.885-21.225) in diabetic subjects and 1.214 (CI: 0.581-2.538) in nondiabetic subjects. We conclude that CFH Y402H polymorphism and SSNHL risk are significantly related, and that diabetic CFH Y402H minor allele carriers may be susceptible to SSNHL.

Polymorphisms in genes involved in inflammatory pathways in patients with sudden sensorineural hearing loss

Although the etiology of idiopathic sudden sensorineural hearing loss (SSNHL) remains unclear, the pathologically increased permeability of blood vessels, elucidated by gadolinium-enhanced magnetic resonance imaging (MRI), suggests the involvement of inflammation. Because SSNHL is considered a multifactorial disease, possibly caused by interactions between genetic factors and environmental factors, the authors investigated the associations of polymorphisms of inflammatory mediator genes with susceptibility to SSNHL. The authors compared 72 patients affected by SSNHL and 2010 adults (1010 men and 1000 women; mean age 59.2 years; range 40-79) who participated in the National Institute for Longevity Sciences Longitudinal Study of Aging. Multiple logistic regression was used to obtain odds ratios (ORs) for SSNHL in subjects with polymorphisms in the genes IL-6 C - 572G, IL-4R G1902A, IL-10 A - 592C, TNFα C - 863A, TNFRSF1B G593A, VEGF C936T, VEGF C - 2578A, and VEGF G - 1154A, with adjustment for age, gender, and any history of hypertension, diabetes, or dyslipidemia. The per-allele OR for the risk of SSNHL in subjects bearing IL-6 C - 572G was 1.480 (95% confidence interval [CI], 1.037-2.111) in model 1 (no adjustment), 1.463 (CI, 1.022-2.094) in model 2 (adjusted for age and gender), and 1.460 (CI, 1.016-2.097) in model 3 (adjusted for age, gender, and a history of hypertension, diabetes, or dyslipidemia). Under the dominant model of inheritance, the ORs were 1.734 (CI, 1.080-2.783) in model 1, 1.690 (CI, 1.050-2.721) in model 2, and 1.669 (CI, 1.035-2.692) in model 3. The remaining seven polymorphisms failed to show any associations with the risk of SSNHL. These data need to be confirmed on larger series of patients. In conclusion, the IL-6 C - 572G polymorphism is associated with a risk of SSNHL. Because permeability of blood vessels in the inner ear is frequently increased in patients with SSNHL, inflammation of the inner ear might be involved.

[Association between cerumen impaction, cognitive function and hearing in Japanese elderly]

AIM

In this study we aimed to evaluate the frequency of cerumen impaction in Japanese elderly and clarify the associations between cerumen, cognitive function, and hearing impairment.

METHODS

The subjects enrolleded in this study were participants in the National Institute for Longevity Sciences, Longitudinal Study of Aging (NILS-LSA). The data of 792 community-dwelling participants aged 60 to 88 years old were collected. All had taken the Mini-Mental State Examination (MMSE) and had undergone pure tone audiometry (PTA) assessment and video recording of an otoscopic examination. We then analyzed associations between the incidence of the cerumen impaction of better-hearing ear, hearing level and MMSE scores using a general linear model.

RESULTS

Cerumen impaction of the better-hearing ear was observed in 10.7% of all participants. In participants with an MMSE score of less than 24, the frequency of cerumen impaction was 23.3%. Cerumen was significant associated with poorer hearing after adjustment for sex and age (p=0.0001). Cerumen impaction also showed a significant association with a low MMSE score after adjustment for sex, age, hearing level and education (p=0.02).

CONCLUSIONS

The frequency of cerumen impaction in Japanese elderly was estimated to be approximately 10%. The existence of cerumen impaction was associated with poorer hearing level and lower MMSE score.

Contribution of 1425G/A polymorphism in protein kinase C-Eta (PRKCH) gene and brain white matter lesions to the risk of sudden sensorineural hearing loss in a Japanese nested case-control study

Protein kinase C-eta (PRKCH) gene has been recently identified as a susceptible risk locus for cerebral infarction and hemorrhage in the Asian populations. The inner ear artery, a usual branch of anterior inferior cerebellar artery, is an end artery with minimal collaterals, therefore, the inner ear is particularly vulnerable to ischemia. The potential association between the development of stroke and sudden sensorineural hearing loss (SSNHL) has been implied. The authors hypothesized that the PRKCH polymorphism predisposing to stroke is associated with SSNHL risk, in view of brain magnetic resonance imaging (MRI) findings. The authors compared 33 cases of prevalent SSNHL with other cases among 2188 adults aged 40 to 79 years who participated in the Study of Aging, to assess the impact of PRKCH 1425G/A polymorphism in consideration of brain MRI findings. Multiple logistic regression was used to obtain odds ratios (ORs) for SSNHL, with adjustment for other possibly influential factors under additive model of minor allele. The per-allele OR for SSNHL risk was 1.770 (95% confidence interval: 1.024-3.060) after adjustments. The effect of the 1425A-allele varied by white matter lesion (WML) status. A significant impact of the A-allele on SSNHL risk increment was observed in higher-WML group, but not in no- or mild-WML group. The 1425A-allele of PRKCH has probably contributed to the susceptibility to SSNHL, despite the etiological heterogeneity of SSNHL, and the impact of the PRKCH 1425A variation observed in this study may imply underlying vascular pathogenesis of SSNHL.

Molecular genetic epidemiology of age-related hearing impairment

Genetic epidemiology focuses on the genetic determinants in the etiology of disease among populations and seeks to elucidate the role of genetic factors and their interaction with environmental factors in disease occurrence. In recent years, genetic epidemiological research has become more focused on complex diseases, and human genome analysis technology has made remarkable advances. Age-related hearing impairment (ARHI) is a complex trait, which results from a multitude of confounding intrinsic and extrinsic factors. Although the number of genetic investigations of ARHI is increasing at a surprising rate, the etiology of ARHI is not firmly established. In this article, we review (1) the methodological strategies used to analyze genetic factors that contribute to human ARHI, (2) several representative investigations, and (3) specific genetic risk factors for human ARHI identified in previous work.

Simultaneous combined intravenous recombinant tissue plasminogen activator and endovascular therapy for hyperacute middle cerebral artery m1 occlusion

We investigated the efficacy and safety of combined intravenous (IV) recombinant tissue plasminogen activator (rtPA) and simultaneous endovascular therapy (ET) for hyperacute middle cerebral artery (MCA) M1 occlusion. Between October 2005 and April 2007, in the combined group, 22 patients eligible for IV rtPA, who were diagnosed as having MCA M1 occlusion, were treated with IV rtPA and simultaneous ET was initiated as soon as possible. The other patients were treated with IV rtPA alone (IV group A: n = 11). Between May 2007 and November 2008, all patients eligible for IV rtPA, who were diagnosed as having MCA M1 occlusion, underwent thrombolysis by IV rtPA alone (IV group B: n = 24). The improvement of the National Institutes of Health Stroke Scale score at 24 hours was highest in the combined group (10 ± 4.1). In contrast, it was 5.1 ± 4.7 in the IV group A (P = 0.017) and 5.6 ± 5.6 in IV group B (P = 0.006). In the combined group, successful recanalization was observed in 18 of 22 patients with one symptomatic intracranial hemorrhage. The rate of mRS0-2 at three months was highest in the combined group, 36% in the IV group A and 33% in the IV group B (P = 0.008).Simultaneous treatment with IV rtPA and ET improved the clinical outcome of MCA M1 occlusion without a significant increase of adverse effects in our study.