Masaki Nagai

Saitama Medical University, Saitama, Saitama, Japan

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Publications (107)208.71 Total impact

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    ABSTRACT: Background: The sentinel surveillance system in Japan provides estimates of nationwide influenza incidence. Although prefectural influenza incidences can be estimated using data from the current surveillance system, such estimates may be imprecise.Methods: We calculated the numbers of sentinel medical institutions (SMIs) needed in the surveillance system to estimate influenza incidences in prefectures, under the assumption that the standard error rates in 75% of influenza epidemic cases are less than 10%. Epidemic cases observed in 47 prefectures during the 2007/2008, 2008/2009, and 2009/2010 seasons, respectively, were used.Results: The present total number of SMIs was 6669. With respect to current standards, the increases required in prefectures ranged from 0 to 59, and the total increase required in the number of SMIs was 1668.Conclusions: We used sentinel surveillance data for Japan to calculate the number of SMIs required to estimate influenza incidence in each prefecture.
    Journal of Epidemiology 03/2014; DOI:10.2188/jea.JE20130077 · 2.86 Impact Factor
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    ABSTRACT: This study aimed to describe the geographical spread and temporal accumulation of cases during the 2009 influenza A (H1N1) epidemic in Japan. Using a method adopted by the National Epidemiological Surveillance of Infectious Diseases (NESID) to identify epidemics, we described the frequency and temporal change of the 2009 influenza A (H1N1) epidemic among designated public health center areas in Japan. We calculated the proportion of public health center areas with an epidemic by week from 1999 to 2010. The 2009 influenza A (H1N1) epidemic had several distinguishing features compared with previous seasonal influenza epidemics. For example, the 2009 epidemic started in autumn and peaked at week 49, almost 10 weeks earlier than that of previous seasonal influenza epidemics. Additionally, the 2009 epidemic had the highest total number of public health center areas reporting an epidemic within a season, but only the second highest proportion of areas with an epidemic in the peak week (78.5%). The duration of the epidemic was 17 weeks, which was longer than that of previous epidemics. The present study results shed light on the epidemiology of the 2009 influenza A (H1N1) pandemic and provide useful information to create strategies to prevent future pandemics.
    Japanese journal of infectious diseases 01/2014; 67(5):368-73. DOI:10.7883/yoken.67.368 · 1.20 Impact Factor
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    ABSTRACT: Objectives. To estimate the number of patients with polymyositis/dermatomyositis (PM/DM) in Japan and the prevalence rate and incidence rate of the disease. Methods. The electronic database in the nationwide registration system on intractable diseases from 2003 to 2010 was utilized to identify the number of prevalent and incident cases of PM/DM. The electronic data entry rate was used to establish the total number of registered cases. Results. The estimated total number of patients with PM/DM and the prevalence rate in Japan in 2010 were 17,000 and 13.2 per 100,000 population, respectively. The prevalence of PM/DM ranged from 10 to 13 per 100,000 population with a trend toward increasing over time. The incidence of PM/DM was estimated within the range 10-13 per 1,000,000 person-years, except for 2003. Conclusions. We report the prevalence and incidence of PM/DM recently in Japan for the first time at the nationwide population level. Because the prevalence seems to be increasing recently, continued monitoring of these epidemiologic features is required.
    Modern Rheumatology 10/2013; DOI:10.3109/14397595.2013.844308 · 2.21 Impact Factor
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    ABSTRACT: Several genome-wide association studies and case-control studies have investigated the relationships between single nucleotide polymorphisms (SNPs) in the BST1 gene and Parkinson's disease (PD), but the results have been inconsistent. We examined the relationships between SNPs rs11931532, rs12645693, and rs11724635 and the risk of sporadic PD in Japan. Included were 229 cases within 6years of onset of PD as defined according to the UK PD Society Brain Bank clinical diagnostic criteria. Controls were 357 inpatients and outpatients without neurodegenerative disease. SNPs rs11931532 and rs12645693 were not significantly related to sporadic PD. Compared with a reference group of subjects with the CC genotype of SNP rs11724635, those with the AA genotype had a marginally significantly increased risk of sporadic PD: the adjusted OR was 1.57 (95% CI: 0.95-2.61, P=0.08). No significant interactions were found between BST1 SNP rs11724635 and smoking or caffeine intake with respect to sporadic PD. The current study failed to detect significant relationships between BST1 SNPs rs11931532, rs12645693, and rs11724635 and sporadic PD; however, the relationship between SNP rs11724635 and sporadic PD was of borderline significance. We do not find evidence for interactions between smoking or caffeine intake and SNP rs11724635 affecting sporadic PD.
    Journal of the neurological sciences 09/2012; 323(1-2). DOI:10.1016/j.jns.2012.09.008 · 2.26 Impact Factor
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    ABSTRACT: It has been suggested that P-glycoprotein (P-gp), the product of multidrug resistance 1 (MDR1) gene, regulates the brain entry of various xenobiotics. Impaired function of P-gp may be associated with an increased risk of Parkinson's disease (PD). The aim of this study was to investigate the impact of a MDR1 C3435T polymorphism on PD risk alone or in combination with environmental factors. A total of 238 patients with PD and 368 controls were genotyped for the MDR1 C3435T polymorphism. Subjects with the TT genotype of the C3435T polymorphism showed a nonsignificantly increased risk of PD (odds ratio (OR) = 1.49, 95% confidence interval (CI) =0.85 - 2.25) compared with those with the CC genotype. A gene-environment interaction was suggested, with a combination of at least one T allele and ever drinking conferring significantly higher risk (OR = 1.83, 95% CI = 1.07 - 3.15, P = 0.029), compared with the CC genotype and never drinking. No significant interaction of smoking or occupational pesticide use with the C3435T polymorphism was observed. Our results suggest that the C3435T polymorphism may not play an important role in PD susceptibility in Japanese. Evidence of an interaction between the C3435T polymorphism and alcohol consumption was suggested.
    Drug Metabolism and Pharmacokinetics 09/2012; 28(2). DOI:10.2133/dmpk.DMPK-12-RG-075 · 2.86 Impact Factor
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    ABSTRACT: OBJECTIVES: The aim of this study was to describe age, gender distribution, and age at onset of systemic lupus erythematosus (SLE), polymyositis/dermatomyositis (PM/DM), and systemic sclerosis (SSc) in Japan. METHODS: We used epidemiological information on 21,405, 6,327, and 10,058 patients with SLE, PM/DM, and SSc, respectively, in a Japanese nationwide registration database of patients with intractable diseases. RESULTS: All three diseases occur predominantly in women, with the female-to-male ratio being 8.2:1, 2.6:1, and 7.7:1 for SLE, PM/DM, and SSc, respectively. The most susceptible age for SLE is 15-44 and 20-39 years for males and females, respectively. For PM/DM it is 45-64 and 40-64 years and for SSc, 50-69 and 40-59 for men and women, respectively. CONCLUSIONS: The basic descriptive epidemiological characteristics of SLE, PM/DM, and SSc in Japan, such as gender distribution, present age, and age at onset, were surveyed nationwide for fiscal 2007. It was found that these characteristics were similar to those in Western populations. Our finding provides new information on the natural history of disease development.
    Modern Rheumatology 08/2012; DOI:10.1007/s10165-012-0733-7 · 2.21 Impact Factor
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    ABSTRACT: Background A recent meta-analysis on the UCHL1 S18Y variant and Parkinson’s disease (PD) showed a significant inverse association between the Y allele and PD; the individual studies included in that meta-analysis, however, have produced conflicting results. We examined the relationship between UCHL1 S18Y single nucleotide polymorphism (SNP) and sporadic PD in Japan. Methods Included were 229 cases within 6 years of onset of PD, defined according to the UK PD Society Brain Bank clinical diagnostic criteria. Controls were 357 inpatients and outpatients without neurodegenerative disease. Adjustment was made for sex, age, region of residence, smoking, and caffeine intake. Results Compared with subjects with the CC or CA genotype of UCHL1 S18Y SNP, those with the AA genotype had a significantly increased risk of sporadic PD: the adjusted OR was 1.57 (95 % CI: 1.06 − 2.31). Compared with subjects with the CC or CA genotype of UCHL1 S18Y and the CC or CT genotype of SNCA SNP rs356220, those with the AA genotype of UCHL1 S18Y and the TT genotype of SNP rs356220 had a significantly increased risk of sporadic PD; the interaction, however, was not significant. Our previous investigation found significant inverse relationships between smoking and caffeine intake and PD in this population. There were no significant interactions between UCHL1 S18Y and smoking or caffeine intake affecting sporadic PD. Conclusions This study reveals that the UCHL1 S18Y variant is a risk factor for sporadic PD. We could not find evidence for interactions affecting sporadic PD between UCHL1 S18Y and SNCA SNP rs356220, smoking, or caffeine intake.
    BMC Neurology 07/2012; 12(1):62. DOI:10.1186/1471-2377-12-62 · 2.49 Impact Factor
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    ABSTRACT: Thyroid storm (TS) is life threatening. Its incidence is poorly defined, few series are available, and population-based diagnostic criteria have not been established. We surveyed TS in Japan, defined its characteristics, and formulated diagnostic criteria, FINAL-CRITERIA1 and FINAL-CRITERIA2, for two grades of TS, TS1, and TS2 respectively. We first developed diagnostic criteria based on 99 patients in the literature and 7 of our patients (LIT-CRITERIA1 for TS1 and LIT-CRITERIA2 for TS2). Thyrotoxicosis was a prerequisite for TS1 and TS2 as well as for combinations of the central nervous system manifestations, fever, tachycardia, congestive heart failure (CHF), and gastrointestinal (GI)/hepatic disturbances. We then conducted initial and follow-up surveys from 2004 through 2008, targeting all hospitals in Japan, with an eight-layered random extraction selection process to obtain and verify information on patients who met LIT-CRITERIA1 and LIT-CRITERIA2. We identified 282 patients with TS1 and 74 patients with TS2. Based on these data and information from the Ministry of Health, Labor, and Welfare of Japan, we estimated the incidence of TS in hospitalized patients in Japan to be 0.20 per 100,000 per year. Serum-free thyroxine and free triiodothyroine concentrations were similar among patients with TS in the literature, Japanese patients with TS1 or TS2, and a group of patients with thyrotoxicosis without TS (Tox-NoTS). The mortality rate was 11.0% in TS1, 9.5% in TS2, and 0% in Tox-NoTS patients. Multiple organ failure was the most common cause of death in TS1 and TS2, followed by CHF, respiratory failure, arrhythmia, disseminated intravascular coagulation, GI perforation, hypoxic brain syndrome, and sepsis. Glasgow Coma Scale results and blood urea nitrogen (BUN) were associated with irreversible damages in 22 survivors. The only change in our final diagnostic criteria for TS as compared with our initial criteria related to serum bilirubin concentration >3 mg/dL. TS is still a life-threatening disorder with more than 10% mortality in Japan. We present newly formulated diagnostic criteria for TS and clarify its clinical features, prognosis, and incidence based on nationwide surveys in Japan. This information will help diagnose TS and in understanding the factors contributing to mortality and irreversible complications.
    Thyroid: official journal of the American Thyroid Association 06/2012; 22(7):661-79. DOI:10.1089/thy.2011.0334 · 3.84 Impact Factor
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    ABSTRACT: Background: Thyrotoxic storm is a life-threatening condition requiring emergency treatment. The condition arises in thyrotoxic patients who manifest decompensation in multiple organs, often triggered by severe stress. Neither its epidemiological data nor diagnostic criteria have been fully established. We attempted to clarify the clinical and epidemiological characteristics of thyroid storm, initially using nationwide surveys and then formulate diagnostic criteria for thyroid storm. Methods and Subjects: To perform the nationwide survey on thyroid storm, we first developed tentative diagnostic criteria for thyroid storm, mainly based upon the literature (the first edition). The tentative diagnostic criteria, which included the requirement that thyrotoxicosis be present, defined definite and suspected cases based on the prerequisite item (the presence of thyrotoxicosis) and combinations of typical clinical features. We then conducted the initial and second nationwide surveys using these criteria, targeting all hospitals in Japan with eight-layered random extraction. Using the results of the second survey, we analyzed the relationship of the major features of thyroid storm to mortality and to certain other features. Finally, based upon the findings of these surveys, we revised the diagnostic criteria. Results: According to the initial nationwide survey, the number of definite and suspected thyroid storm cases was estimated to be 1,283 ± 105 (95% confidence interval: 1,077 - 1,489) per five years (0.20 persons/100,000 Japanese population/year). Thyroid storm occurred in 0.22% of thyrotoxic patients. The second nationwide survey obtained detailed clinico-epidemiologic features of 282 definite and 74 suspected cases. The mortality rates of definite and suspected cases were 11.0% and 9.5%, respectively. Finally, based on the results of these surveys, we propose a revision of the diagnostic criteria (the second edition). Conclusions: Thyrotoxic storm is still a life-threatening disorder with over 10% mortality in Japan. We newly formulated diagnostic criteria for this disorder.
    Thyroid: official journal of the American Thyroid Association 04/2012; DOI:10.1089/thy.2011-0334 · 3.84 Impact Factor
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    ABSTRACT: Several case-control studies and genome-wide association studies have examined the relationships between single nucleotide polymorphisms (SNPs) in the SNCA gene and Parkinson's disease (PD), and have provided inconsistent results. We investigated the relationships between SNPs rs356229, rs356219, rs356220, rs7684318, and rs2736990 and the risk of sporadic PD in Japan using data from a multicenter hospital-based case-control study. Included were 229 cases within 6 years of onset of PD as defined according to the UK PD Society Brain Bank clinical diagnostic criteria. Controls were 357 inpatients and outpatients without neurodegenerative disease. Adjustment was made for sex, age, region of residence, and smoking. Based on the recessive model, compared with subjects with the CC or CT genotype of SNP rs356220, those with the TT genotype had a significantly increased risk of sporadic PD: the adjusted OR was 1.42 (95% CI: 1.002-2.02). In the additive model, SNP rs2736990 was significantly related to the risk of sporadic PD: the adjusted OR was 1.30 (95% CI: 1.002-1.68). There were no significant relationships between SNP rs356229, rs356219, or rs7684318 and the risk of sporadic PD in any genetic model. The additive interactions between SNPs rs356219 and rs356220 and smoking with respect to sporadic PD were significant although the multiplicative interactions were not significant. This study suggests that SNCA SNPs rs356220 and rs2736990 are significantly associated with the risk of sporadic PD in Japanese. We also present new evidence for biological interactions between SNPs rs356219 and rs356220 and smoking that affect sporadic PD.
    Parkinsonism & Related Disorders 03/2012; 18(5):557-61. DOI:10.1016/j.parkreldis.2012.02.016 · 4.13 Impact Factor
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    ABSTRACT: Nearly all epidemiologic studies examining the association between the risk of Parkinson's disease (PD) and diet have focused on single foods and specific nutrients. However, epidemiologic evidence for the association of dietary pattern with PD, namely the measurement of overall diet by considering the cumulative effects of nutrients is extremely limited. We conducted a hospital-based case-control study in Japan to examine the relationship between dietary patterns and the risk of PD. Patients with PD diagnosed using the UK PD Society Brain Bank criteria (n = 249) and controls without neurodegenerative diseases (n = 368) were recruited. At the time of recruitment, dietary intake during the preceding 1 month was assessed using a validated, self-administered diet history questionnaire. Dietary patterns from 33 predefined food groups (energy-adjusted food g/day) were extracted by factor analysis. Three dietary patterns were identified: 'Healthy', 'Western' and 'Light meal' patterns. After adjustment for potential non-dietary confounding factors, the Healthy pattern, characterized by a high intake of vegetables, seaweed, pulses, mushrooms, fruits and fish, was inversely associated with the risk of PD with a border-line significance (P for trend = 0.06). Multivariate Odds ratio (95% confidence intervals) for PD in the highest quartile of the Healthy pattern was 0.54 (0.32-0.92) compared with the lowest quartile. No associations with PD were detected for the other two dietary patterns. In this case-control study in Japan, a dietary pattern consisting of high intakes of vegetables, fruits and fish may be associated with a decreased risk of PD.
    European Journal of Neurology 12/2011; 19(5):681-8. DOI:10.1111/j.1468-1331.2011.03600.x · 3.85 Impact Factor
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    ABSTRACT: Parkinson's disease (PD) is characterized by alterations in dopaminergic neurotransmission. Genetic polymorphisms involved in dopaminergic neurotransmission may influence susceptibility to PD. We investigated the relationship of catechol-O-methyltransferase (COMT), monoamine oxidase B (MAOB), dopamine receptor (DR) D2 and DRD4 polymorphisms and PD risk with special attention to the interaction with cigarette smoking among 238 patients with PD and 369 controls in a Japanese population. Subjects with the AA genotype of MAOB rs1799836 showed a significantly increased risk of PD (odds ratio (OR) = 1.70, 95% confidence interval (CI) = 1.12 - 2.58) compared with the AG and GG genotypes combined. The AA genotype of COMT rs4680 was marginally associated with an increased risk of PD (OR = 1.86, 95% CI = 0.98 - 3.50) compared with the GG genotype. The DRD2 rs1800497 and DRD4 rs1800955 polymorphisms showed no association with PD. A COMT -smoking interaction was suggested, with the combined GA and AA genotypes of rs4680 and non-smoking conferring significantly higher risk (OR = 3.97, 95% CI = 2.13 - 7.41) than the AA genotype and a history of smoking (P for interaction = 0.061). No interactions of smoking with other polymorphisms were observed. The COMT rs4680 and MAOB rs1799836 polymorphisms may increase susceptibility to PD risk among Japanese. Future studies involving larger control and case populations and better pesticide exposure histories will undoubtedly lead to a more thorough understanding of the role of the polymorphisms involved in the dopamine pathway in PD.
    BMC Neurology 07/2011; 11:89. DOI:10.1186/1471-2377-11-89 · 2.49 Impact Factor
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    ABSTRACT: Metals are involved in several important functions in the nervous system. Zinc and iron are increased and copper is decreased in the substantia nigra in Parkinson's disease (PD). However, epidemiological evidence for the association of dietary intake of metals with the risk of PD is limited. We investigated the relationship between metal consumption and the risk of PD in Japan using data from a multicenter hospital-based case-control study. Included were 249 cases within 6 years of onset of PD based on the UK PD Society Brain Bank clinical diagnostic criteria. Controls were 368 inpatients and outpatients without a neurodegenerative disease. Information on dietary factors was collected using a self-administered diet history questionnaire. Higher intake of iron, magnesium, and zinc was independently associated with a reduced risk of PD: the adjusted OR in the highest quartile was 0.24 (95% CI: 0.10-0.57, P for trend=0.0003) for iron, 0.33 (95% CI: 0.13-0.81, P for trend=0.007) for magnesium and 0.50 (95% CI: 0.26-0.95, P for trend=0.055) for zinc. There were no relationships between the intake of copper or manganese and the risk of PD. Higher intake of iron, magnesium, and zinc may be protective against PD.
    Journal of the neurological sciences 07/2011; 306(1-2):98-102. DOI:10.1016/j.jns.2011.03.035 · 2.26 Impact Factor
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    ABSTRACT: The evidence for associations between occupational factors and the risk of Parkinson's disease (PD) is inconsistent. We assessed the risk of PD associated with various occupational factors in Japan. We examined 249 cases within 6 years of onset of PD. Control subjects were 369 inpatients and outpatients without neurodegenerative disease. Information on occupational factors was obtained from a self-administered questionnaire. Relative risks of PD were estimated using odds ratios (ORs) and 95% confidence intervals (CIs) based on logistic regression. Adjustments were made for gender, age, region of residence, educational level, and pack-years of smoking. Working in a professional or technical occupation tended to be inversely related to the risk of PD: adjusted OR was 0.59 (95% CI: 0.32-1.06, P = 0.08). According to a stratified analysis by gender, the decreased risk of PD for persons in professional or technical occupations was statistically significant only for men. Adjusted ORs for a professional or technical occupation among men and women were 0.22 (95% CI: 0.06-0.67) and 0.99 (0.47-2.07), respectively, and significant interaction was observed (P = 0.048 for homogeneity of OR). In contrast, risk estimates for protective service occupations and transport or communications were increased, although the results were not statistically significant: adjusted ORs were 2.73 (95% CI: 0.56-14.86) and 1.74 (95% CI: 0.65-4.74), respectively. No statistical significance was seen in data concerning exposure to occupational agents and the risk of PD, although roughly a 2-fold increase in OR was observed for workers exposed to stone or sand. The results of our study suggest that occupational factors do not play a substantial etiologic role in this population. However, among men, professional or technical occupations may decrease the risk of PD.
    BMC Neurology 07/2011; 11:83. DOI:10.1186/1471-2377-11-83 · 2.49 Impact Factor
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    ABSTRACT: To clarify the prevalence and clinical characteristics of myasthenia gravis (MG) in Japan. We performed a nationwide epidemiological survey of MG in Japan. The clinical features were compared among five groups of patients, divided according to onset age. A generalized additive model (GAM) was used to assess the linearity of these relationships. A total of 8542 patients were reported, and detailed data were analyzed for 3141 patients. The estimated number of MG patients in Japan was 15,100, giving a prevalence of 11.8 per 100,000. Elderly-onset MG (≥ 65 years) accounted for 7.3% in 1987 (adjusted for population in 2005), but this had increased to 16.8% in 2006. Infantile-onset MG (0-4 years) accounted for 10.1% in 1987, and was still as high as 7.0% in 2006. The rate of ocular MG was highest (80.6%) in infantile-onset and lowest (26.4%) in early-onset disease, but the rate rose again in the late-onset group. GAM analysis of the ocular form showed a U-shaped curve, with a dip in the 20s. Anti-acetylcholine receptor antibodies were positive in only 50% of infantile-onset, but nearly 90% of elderly-onset patients. GAM analyses assessing the concurrence of thymoma and hyperplasia both showed reversed U-shapes, with peaks in the 50s and 20s-40s, respectively. Persistent high incidence of infantile-onset disease and clinical heterogeneity according to onset age are characteristic features of MG in Japan.
    Journal of the neurological sciences 03/2011; 305(1-2):97-102. DOI:10.1016/j.jns.2011.03.004 · 2.26 Impact Factor
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    ABSTRACT: Apolipoprotein E (APOE) is associated with increased oxidative stress, which is caused by reactive oxygen species (ROS). Enhanced cytochrome P450 2E1 (CYP2E1) activity may also increase formation of neurotoxins such as ROS. As Parkinson's disease (PD) is a neurodegenerative disorder, both the APOE and CYP2E1 genes that are involved in neurodegeneration by oxidative stress may be associated with PD risk. We investigated the relationship of the APOE and CYP2E1 rs2864987 polymorphisms and PD risk with special attention to the interaction with alcohol consumption among 238 patients with PD and 296 controls in a Japanese population. The frequencies of the ɛ2, ɛ3, and ɛ4 alleles of the APOE polymorphism among controls were 3.72, 86.7, and 9.63%, respectively. As compared with the APOE ε3/ε3 genotype, the 2/ε4 genotype was associated with an increased risk of PD (adjusted odds ratio (OR) = 9.50, 95% (confidence interval) CI = 1.12-80.6). The presence of the ε3 allele was associated with a decreased risk of PD. Meanwhile, CYP2E1 rs2864987 was not associated with PD risk. Although CYP2E1 is involved in the metabolism of alcohol, there was no evidence of interaction between alcohol consumption and CYP2E1 rs2864987. Our results suggested that the APOE polymorphism might play an important role in PD susceptibility in our Japanese population. Future studies involving larger control and case populations and better alcohol consumption histories will undoubtedly lead to a more thorough understanding of the role of polymorphisms of genes related to the generation of ROS in PD development.
    Journal of Neural Transmission 03/2011; 118(9):1335-44. DOI:10.1007/s00702-011-0612-y · 2.87 Impact Factor
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    ABSTRACT: Studies that have addressed the association between the intake of coffee or caffeine and Parkinson's disease (PD) were conducted mainly in Western countries. Little is known about this relationship in an Asian population. Therefore, we performed an assessment of the association of the intake of coffee, other caffeine-containing beverages, and caffeine with the risk of PD in Japan. The study involved 249 PD cases and 368 control subjects. Information on dietary factors was obtained through a self-administered diet history questionnaire. Adjustment was made for sex, age, region of residence, educational level, pack-years of smoking, body mass index, the dietary glycemic index, and intake of cholesterol, vitamin E, β-carotene, vitamin B(6,) alcohol, and iron. Intake of coffee, black tea, and Japanese and Chinese teas was significantly inversely associated with the risk of PD: the adjusted odds ratios in comparison of the highest with the lowest quartile were 0.52, 0.58, and 0.59, respectively (95% confidence intervals = 0.30-0.90, 0.35-0.97, and 0.35-0.995, respectively). A clear inverse dose-response relationship between total caffeine intake and PD risk was observed. We confirmed that the intake of coffee and caffeine reduced the risk of PD. Furthermore, this is the first study to show a significant inverse relationship between the intake of Japanese and Chinese teas and the risk of PD.
    Parkinsonism & Related Disorders 03/2011; 17(6):446-50. DOI:10.1016/j.parkreldis.2011.02.016 · 4.13 Impact Factor
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    ABSTRACT: Three previous cohort studies in the USA reported that dairy product consumption was significantly associated with an increased risk of Parkinson's disease (PD) in men, but not in women. We examined the relationship between consumption of dairy products, calcium, and vitamin D and the risk of PD using data from a multicenter hospital-based case-control study in Japan. Included were 249 cases within 6 years of onset of PD based on the UK PD Society Brain Bank clinical diagnostic criteria. Controls were 368 inpatients and outpatients without a neurodegenerative disease. Information on dietary factors was collected using a validated self-administered diet history questionnaire. Adjustment was made for sex, age, region of residence, pack-years of smoking, years of education, body mass index, and dietary factors including cholesterol, dietary glycemic index, vitamin E, β-carotene, vitamin B(6), caffeine, iron, and alcohol. Total dairy product consumption was not materially associated with the risk of PD (P for trend = 0.62). No evident relationships were observed between intake of milk, yogurt, cheese, or ice cream and the risk of PD (P for trend = 0.75, 0.63, 0.59, and 0.35, respectively). There were no measurable associations between consumption of calcium or vitamin D and PD (P for trend = 0.37 and 0.69, respectively). No significant interactions were observed between the dietary exposures and sex regarding PD. Our results suggest that intake of dairy products, calcium, and vitamin D was not related to PD, regardless of sex. However, such null relationships might be a consequence of PD.
    Parkinsonism & Related Disorders 02/2011; 17(2):112-6. DOI:10.1016/j.parkreldis.2010.11.018 · 4.13 Impact Factor
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    ABSTRACT: antioxidant vitamins are expected to protect cells from oxidative damage by neutralizing the effects of reactive oxygen species. However, epidemiological evidence regarding the associations between antioxidant vitamin intake and Parkinson's disease (PD) is limited and inconsistent. We investigated the relationship between dietary intake of selected antioxidant vitamins, vegetables and fruit and the risk of PD in Japan using data from a multicenter hospital-based case-control study. included were 249 patients within 6 years of onset of PD. Controls were 368 inpatients and outpatients without a neurodegenerative disease. Information on dietary factors was collected using a validated self-administered diet history questionnaire. Adjustment was made for sex, age, region of residence, pack-years of smoking, years of education, body mass index, dietary intake of cholesterol, alcohol, total dairy products, and coffee and the dietary glycemic index. higher consumption of vitamin E and β-carotene was significantly associated with a reduced risk of PD after adjustment for confounders under study: the adjusted odds ratio in the highest quartile was 0.45 (95% confidence interval [CI]: 0.25-0.79, P for trend = 0.009) for vitamin E and 0.56 (95% CI: 0.33-0.97, P for trend = 0.03) for β-carotene. Stratified by sex, such inverse associations were significant only in women. No material relationships were shown between intake of vitamin C, α-carotene, cryptoxanthin, green and yellow vegetables, other vegetables, or fruit and the risk of PD. higher intake of vitamin E and β-carotene may be associated with a decreased risk of PD.
    European Journal of Neurology 01/2011; 18(1):106-13. DOI:10.1111/j.1468-1331.2010.03088.x · 3.85 Impact Factor
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    ABSTRACT: Although some epidemiologic studies found inverse associations between alcohol drinking and Parkinson's disease (PD), the majority of studies found no such significant associations. Additionally, there is only limited research into the possible interactions of alcohol intake with aldehyde dehydrogenase (ALDH) 2 activity with respect to PD risk. We examined the relationship between alcohol intake and PD among Japanese subjects using data from a case-control study. From 214 cases within 6 years of PD onset and 327 controls without neurodegenerative disease, we collected information on "peak", as opposed to average, alcohol drinking frequency and peak drinking amounts during a subject's lifetime. Alcohol flushing status was evaluated via questions, as a means of detecting inactive ALHD2. The multivariate model included adjustments for sex, age, region of residence, smoking, years of education, body mass index, alcohol flushing status, presence of selected medication histories, and several dietary factors. Alcohol intake during peak drinking periods, regardless of frequency or amount, was not associated with PD. However, when we assessed daily ethanol intake separately for each type of alcohol, only Japanese sake (rice wine) was significantly associated with PD (adjusted odds ratio of ≥66.0 g ethanol per day: 3.39, 95% confidence interval: 1.10-11.0, P for trend = 0.001). There was no significant interaction of alcohol intake with flushing status in relation to PD risk. We did not find significant associations between alcohol intake and PD, except for the daily amount of Japanese sake. Effect modifications by alcohol flushing status were not observed.
    BMC Neurology 11/2010; 10:111. DOI:10.1186/1471-2377-10-111 · 2.49 Impact Factor

Publication Stats

1k Citations
208.71 Total Impact Points

Institutions

  • 1996–2014
    • Saitama Medical University
      • Department of Public Health
      Saitama, Saitama, Japan
  • 1996–2010
    • The University of Tokyo
      • • School of Public Health
      • • Department of Health Science and Nursing
      Tokyo, Tokyo-to, Japan
  • 2009
    • Aichi Prefectural College of Nursing & Health
      • Department of Public Health, Aichi Prefectural College of Nursing and Health
      Nagoya, Aichi, Japan
  • 2004
    • National Institute for Environmental Studies
      • Center for Environmental Health Sciences
      Tsukuba, Ibaraki, Japan
  • 2003
    • Fujita Health University
      • Department of Hygiene
      Nagoya, Aichi, Japan
  • 2000
    • Oita University of Nursing and Health Sciences
      Ōita, Ōita, Japan
  • 1995
    • Jichi Medical University
      • Department of Public Health
      Totigi, Tochigi, Japan