Mika Yamawaki

Changes in prevalence and incidence of Parkinson's disease in Japan during a quarter of a century.

Background/Aim: To determine the prevalence and incidence of Parkinson’s disease (PD) and compare them with results from our previous studies. Methods: We examined epidemiological characteristics of PD patients using a service-based study in Yonago City, and a door-to-door study in Daisen Town. The prevalence days were April 1, 2004 in Yonago, and April 1, 2003 in Daisen. Results: In Yonago, we identified 254 PD patients. The crude prevalence was 180.3 (95% CI, 158.1–202.4) per 100,000 population. The adjusted prevalence was 145.8 (95% CI, 145.2–146.5) in 1980, 147.0 (95% CI, 146.3–147.6) in 1992, and 166.8 (95% CI, 166.1–167.5) in 2004, when calculated using the Japanese population in 2004. The crude incidence was 18.4 (95% CI, 11.3–25.5) per 100,000 population per year. The crude incidence in 1980 was 10.2 (95% CI, 4.6–15.8), and the adjusted incidence was 9.8 (95% CI, 4.3–15.3) in 1992, and 10.3 (95% CI, 4.7–15.9) in 2004, when calculated using the population in Yonago in 1980. In Daisen, there were 21 PD patients. The crude prevalence was 306.6 (95% CI, 175.7–437.6) and the adjusted prevalence was 192.6 (95% CI, 191.9–193.8). Conclusions: The prevalence of PD had increased, primarily because the population had aged. Differences in prevalence between these adjacent areas may have resulted from differences in the methods of investigation.

Validation of the Parkinson's disease sleep scale in Japanese patients: A comparison study using the Pittsburgh Sleep Quality Index, the Epworth Sleepiness Scale and Polysomnography

OBJECTIVE Characteristic sleep disturbance in patients with Parkinsons disease (PD) was evaluated using a subjective questionnaire called the PD sleep scale (PDSS). In this study we sought to examine the relationship between the results from the PDSS with those from the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), and polysomnography (PSG) in Japanese PD patients. SUBJECTS AND METHODS Subjects were 79 PD patients and 79 age and gender matched controls. The length of morbidity in patients with PD was 8.4+/-8.0 years, and their Hoehn and Yahr grade was 2.9+/-1.0. All subjects completed the PDSS, PSQI, and ESS questionnaires, and we compared the results from patients with PD to controls. We also evaluated the correlation among the PDSS, PSQI, and ESS in patients with PD. Moreover, we performed PSG on 33 of 79 PD patients, and examined the correlation between the PDSS and PSG. RESULTS PDSS total scores and subscales from patients with PD were significantly lower than those in controls, except for items 3, 8, and 14. PDSS scores had significant internal consistency and significant correlation with PSQI and ESS scores. The total PDSS score also correlated with sleep efficiency as measured by PSG. In subscales of the PDSS, night psychosis was negatively correlated with percentage of REM sleep without atonia on PSG. DISCUSSION Based on our comparisons with PSQI, ESS, and PSG, the PDSS appears to be a reliable tool to evaluate the characteristics of sleep disturbances in PD patients.

Prevalence of Dementia and Mild Cognitive Impairment in the Rural Island Town of Ama-cho, Japan

Aims: In order to determine the prevalence of dementia and mild cognitive impairment (MCI), we conducted a population-based study in Japan. Methods: Participants included 924 subjects aged 65 years or older who resided in the town of Ama-cho. In phase 1 of the study, the Mini-Mental State Examination and Clinical Dementia Rating were administered for screening purposes. In phase 2 of the study, the subjects who screened positive were further examined by neurologists. Dementia and MCI were diagnosed by means of DSM-IV and International Working Group on MCI criteria, respectively. Results: By the prevalence date of June 1, 2010, 24 subjects had deceased or lived outside the town. In total, 723 of the remaining 900 subjects received a phase 1 test. In phase 2, 98 subjects were diagnosed with amnestic MCI, 113 subjects with non-amnestic MCI, and 82 subjects with dementia. Of the subjects who did not receive the phase 1 test, 66 subjects were diagnosed as having dementia according to data from their town medical card or the Long-term Care Insurance System. The crude prevalence of amnestic MCI, non-amnestic MCI, and dementia were 10.9, 12.6, and 16.4%, respectively. Conclusion: Consistent with the striking increase in the number of elderly individuals, we report higher prevalence of MCI and dementia in Japan than previously described.

Association of cerebral white matter lesions with cognitive function and mood in Japanese elderly people: a population-based study

To determine the relationships between regional white matter lesions (WMLs), lifestyle factors, and cognitive, motor function and mood.

Epidemiological Survey of Frontotemporal Lobar Degeneration in Tottori Prefecture, Japan

Background: The prevalence of frontotemporal lobar degeneration (FTLD) in Japan is unknown. An epidemiological survey study of FTLD was undertaken in Tottori Prefecture, a district in the western region of Japan. Methods: Hospitals in Tottori Prefecture were surveyed by a two-step questionnaire in 2010, and the prevalence of FTLD per 100,000 inhabitants was calculated using the actual number of patients and inhabitants in Tottori Prefecture on the prevalence day of October 1, 2010. Results: In this survey, 66 patients were diagnosed with FTLD. The subtypes of FTLD were as follows: 62 cases of frontotemporal dementia (FTD), 3 cases of progressive nonfluent aphasia, and 1 case of semantic dementia. Among the FTD cases, 5 cases were FTD with motor neuron disease and 1 case was FTD with parkinsonism linked to chromosome 17. The prevalence of FTD in the total population of Tottori Prefecture was 11.2 per 100,000 inhabitants. Based on these results, the prevalence of FTLD in Japan in 2008 was estimated to be 9.5 per 100,000 individuals. Conclusions: Our epidemiological survey results suggest that there are at least 12,000 FTLD patients in Japan, indicating that FTLD is not a rare disease.

Clinical assessment and prevalence of parkinsonism in Japanese elderly people.

Parkinsonism is often observed in the elderly. To clarify the prevalence of parkinsonism‐associated diseases and conditions, we conducted a population‐based study in a rural island town in western Japan, Ama‐cho.

Longitudinal course of mild parkinsonian signs in elderly people: A population-based study in Japan.

We aimed to clarify the longitudinal course of mild parkinsonian signs (MPS) and their association with dementia and functional disability by conducting a comprehensive epidemiological study, including brain MRI, and assessments of cognition, depression, and sleep, in people aged ≥65years living in Ama-cho. We diagnosed MPS and parkinsonism (PS) using a modified Unified Parkinsons Disease Rating Scale. The phase I study was conducted between 2008 and 2010 (n=729) and the phase II between 2011 and 2013 (n=436). By phase II, 8.5% of the phase I participants without PS had developed PS. In addition to older age, a lower Mini-Mental State Examination (MMSE) score, and lower body mass index, the MPS rigidity subtype was a significant independent predictor of PS onset. By phase II, 10.1% of the participants without dementia or PS at phase I had developed dementia. Older age, lower MMSE score, and the axial dysfunction and tremor MPS subtypes were significant independent predictors of dementia development. By phase II, 38.8% of participants with MPS at phase I showed no motor symptoms. Younger age and adequate sleep were significant predictors for this reversion. Periventricular and deep white matter hyperintensity Fazekas scores increased with the evolution of parkinsonian signs. MPS is therefore critically, although sometimes reversibly, associated with PS and dementia development in elderly people.

Intrathecal Isoniazid for Refractory Tuberculous Meningitis with Cerebral Infarction

A 30-year-old Vietnamese woman, about 19 weeks pregnant, was admitted for acute cerebral infarction with stenosis of the left middle cerebral artery (LMCA), tuberculous meningitis, and miliary tuberculosis. Treatment with heparin, quadruple anti-tuberculosis therapy, and dexamethasone afforded prompt symptomatic improvement. However, she delivered a stillbirth, after which there was recurrence of acute cerebral infarction with LMCA occlusion, sinus thrombosis, and cranial base inflammation. A thrice-weekly 100 mg dose of intrathecal isoniazid (INH) improved the signs of meningeal inflammation. The patient was discharged ambulatory after 7 months. In refractory tuberculous meningitis, multimodal therapy with intrathecal INH and steroids should be considered.

Association between exercise habits and subcortical gray matter volumes in healthy elderly people: A population-based study in Japan

Background and aims The relationship between exercise and subcortical gray matter volume is not well understood in the elderly population, although reports indicate that exercise may prevent cortical gray matter atrophy. To elucidate this association in the elderly, we measured subcortical gray matter volume and correlated this with volumes to exercise habits in a community-based cohort study in Japan. Methods Subjects without mild cognitive impairment or dementia (n = 280, 35% male, mean age 73.1 ± 5.9 years) were evaluated using the Mini-Mental State Examination (MMSE), an exercise habit questionnaire, and brain magnetic resonance imaging. Subcortical gray matter volume was compared between groups based on the presence/absence of exercise habits. The MMSE was re-administered 3 years after the baseline examination. Results Ninety-one subjects (32.5%) reported exercise habits (exercise group), and 189 subjects (67.5%) reported no exercise habits (non-exercise group). Volumetric analysis revealed that the volumes in the exercise group were greater in the left hippocampus (p = 0.042) and bilateral nucleus accumbens (left, p = 0.047; right, p = 0.007) compared to those of the non-exercise group. Among the 195 subjects who received a follow-up MMSE examination, the normalized intra-cranial volumes of the left nucleus accumbens (p = 0.004) and right amygdala (p = 0.014)showed significant association with a decline in the follow-up MMSE score. Conclusion Subjects with exercise habits show larger subcortical gray matter volumes than subjects without exercise habits in community-dwelling elderly subjects in Japan. Specifically, the volume of the nucleus accumbens correlates with both exercise habits and cognitive preservation.

54. The relationship between the Parkinson’s disease sleep scale and polysomnography

Primary hemifacial spasm (HFS) is usually related to a vascular compression of the facial nerve at its root exit zone from the brainstem, and it may result in latent facial nerve injury. Axonal stimulating single-fiber EMG (a-SFEMG) was used to investigate whether facial axons are affected in HFS patients. Facial nerve conduction and a-SFEMG of the orbicularis oculi were performed in 30 patients with HFS and 20 patients with blepharospasm (BS). All the patients had not received prior botulinum toxin treatment. Amplitudes of compound muscle action potentials did not significantly differ between the affected side and non-affected side in HFS patients, and between patients with HFS and those with BS. However, jitter (mean consecutive difference) was significantly greater in the HFS group than in the BS group (p = 0.005). After an initial botulinum toxin injection (10 IU) in the O. oculi, 20% of the HFS patients and 5% of the BS patients presented lagophthalmos. These results suggest that HFS is associated with mild facial nerve injury, and this can lead to vulnerability to botulinum injection.