Akira Eboshida

Childhood leukemia and magnetic fields in Japan: A case-control study of childhood leukemia and residential power-frequency magnetic fields in Japan

Residential power‐frequency magnetic fields (MFs) were labeled as a possible human carcinogen by the International Agency for Research on Cancer panel. In response to great public concern, the World Health Organization urged that further epidemiologic studies be conducted in high‐exposure areas such as Japan. We conducted a population‐based case‐control study, which covered areas inhabited by 54% of Japanese children. We analyzed 312 case children (0–15 years old) newly diagnosed with acute lymphoblastic leukemia (ALL) or acute myelocytic leukemia (AML) in 1999–2001 (2.3 years) and 603 controls matched for gender, age and residential area. Weekly mean MF level was determined for the childs bedroom. MF measurements in each set of a case and controls were carried out as closely in time as possible to control for seasonal variation. We evaluated the association using conditional logistic regression models. The odds ratios for children whose bedrooms had MF levels of 0.4 μT or higher compared with the reference category (MF levels below 0.1 μT) was 2.6 (95% CI = 0.76–8.6) for AML + ALL and 4.7 (1.15–19.0) for ALL only. Controlling for some possible confounding factors did not alter the results appreciably. Even an analysis in which selection bias was maximized did not fully explain the association. Most of the leukemia cases in the highest exposure category had MF levels far above 0.4 μT. Our results provided additional evidence that high MF exposure was associated with a higher risk of childhood leukemia, particularly of ALL.

Increasing Prevalence of Japanese Cedar Pollinosis: A Meta-Regression Analysis

Background: Japanese cedar pollinosis, caused by the pollen of the Japanese cedar tree (Cryptomeria japonica), is the commonest seasonal allergic disease in Japan. A number of epidemiological surveys have been reported on Japanese cedar pollinosis, but it has never been assessed systematically or quantitatively. To confirm the increasing prevalence of Japanese cedar pollinosis and related factors, we conducted a meta-regression analysis on population-based surveys in Japan. Methods: We searched for data from population-based surveys in which serological methods were used to test all participants. Weighted regression of logit-transformed prevalence and sensitization rates were used to evaluate the effects of the year of survey, age, and degree of urbanization. We also analyzed the relationship between prevalence and sensitization rate. Results: Thirty-eight reports with 27 subgroups for prevalence and 134 subgroups for sensitization rate were selected from the literature published in the years between 1986 and 2000. The Japanese cedar pollen sensitization rate was found to be significantly correlated with the year of survey, age, and degree of urbanization (adjusted R2 = 0.55). The coefficient for the correlation between the prevalence and the sensitization rate revealed a statistically significant correlation (Pearson’s r = 0.70, p < 0.001). Conclusions: The prevalence of Japanese cedar pollinosis among adolescents was predicted to be 28.7% in metropolitan areas and 24.5% in the general population in urban areas in the year 2004, derived from the estimated sensitization rate and the relationship between sensitization rate and prevalence. The prevalence of Japanese cedar pollinosis increased 2.6-fold between 1980 and 2000, and the prevalence differed considerably according to age and degree of urbanization.

Health-related quality of life of mothers of children with leukemia in Japan.

Objective: The study compared the health-related quality of life (HRQOL) of Japanese mothers of children with leukemia to that of mothers of children without leukemia. Method: We used the Medical Outcomes Study 36-item Short-Form (SF-36) to measure the HRQOL of 97 mothers of children (average age 6.2, range 0–14) with leukemia diagnosed between 1999 and 2000, and compared their scores to those of 240 mothers of children without leukemia matched to the children with leukemia. Main results: Of the eight unadjusted domain scores of the SF-36, five were significantly low among mothers of children with leukemia compared to mothers of children without leukemia: ‘role-physical functioning’ (RP), ‘general health perception’ (GH), ‘vitality’ (VT), ‘social functioning’ (SF) and ‘mental health’ (MH). Their SF-36 domain scores, when adjusted for demographic and clinical factors were also significantly low in RP, GH, VT, SF, RE and MH. The MH and SF scores in mothers of children with leukemia requiring hospital care were, respectively, approximately 20 points (1 standard deviation (SD), p < 0.0001) and 30 points (1.5 SD, p < 0.0001) lower than that of mothers of children without leukemia. Conclusion: Mothers of children with leukemia requiring hospital care have poor HRQOL, particularly with regard to mental health and social functioning, and are at a greater risk for depression. These results suggest that the current system for treating leukemic diseases of children in Japan should also include close monitoring of mothers’ mental health, and provision of appropriate treatment and psycho-social support.

Nationwide Cross-Sectional Population-Based Study on the Prevalences of Asthma and Asthma Symptoms among Japanese Adults

Background: Asthma is a common respiratory disease worldwide. However, few reports are available on the prevalences of asthma and asthma symptoms among Asian subjects. Methods: To determine the prevalences of asthma and asthma symptoms among Japanese subjects, we performed a nationwide cross-sectional, population-based study on Japanese adults aged 20–79 years. Ten areas spread throughout the country were randomly selected. Door-to-door or postal surveys were performed using a translated version of the European Community Respiratory Health Survey questionnaire. Results: The survey was completed by 23,483 participants. The overall response rate was 70.6%. The prevalences of wheeze and current asthma among all participants aged 20–79 years were 10.1% (95% CI: 9.7–10.5%) and 4.2% (95% CI: 4.0–4.5%), respectively. The prevalences among young adults aged 20–44 years were 9.3% (95% CI: 8.7–9.9%) and 5.3% (95% CI: 4.8–5.8%), respectively. The prevalence of current asthma was highest in females aged 30–39 years in comparison with the other gender and age groups. Conclusions: This nationwide study determined the prevalences of asthma and asthma symptoms among Japanese adults. The results provide fundamental information on the respiratory health of Japanese adults.

Enhanced biological activity of polymeric osteopontin

Osteopontin is a multifunctional glycoprotein with roles in immunomodulation, inflammatory response, tissue mineralization, and tissue remodeling, which are mediated primarily through integrins. Transglutaminase 2 selectively cross‐links proteins by isopeptide bonding. Osteopontin is one of the substrates of this enzyme and undergoes polymerization; however, the biological meaning of this polymerization remains unknown. Using recombinant osteopontin polymerized with purified transglutaminase 2, we examined cell adhesion, spreading, focal contact formation, and migration of SW480 or HUVE cells. All of these cellular behaviors were dramatically enhanced with polymeric osteopontin. These enhancements of cellular functions imply that polymerization might modulate physiological and pathological functions of osteopontin.

Asian dust and daily all-cause or cause-specific mortality in western Japan

Objective Desert dust, which is included in course particles, is considered to have potential toxicity. The effect modification of desert dust on associations between anthropogenic air pollution and mortality has been evaluated. However, the independent effects of Asian dust are less clear. Thus, we evaluated the effects of Asian dust on mortality independent of particulate matter (PM) in western Japan. Methods We obtained daily mean concentrations of Asian dust using Light Detection and Ranging measurements and suspended particulate matter (SPM) concentrations (approximately PM8) during March 2005 to December 2010. We then evaluated city-specific associations of Asian dust and SPM with daily mortality using a time-series analysis targeting 1 379 052 people aged 65 or above living in 47 cities. The city-specific results were then combined with a Bayesian-hierarchical model. Results Asian dust did not modify the effects of SPM on mortality. Meanwhile, Asian dust was adversely associated with mortality independent of SPM. The excess risk following a 10 μ/m3 increase in mean of the current to the previous 2 days Asian dust concentration was 0.6% (95% CI 0.1 to 1.1) for heart disease, 0.8% (95% CI 0.1 to 1.6) for ischaemic heart disease, 2.1% (95% CI 0.3 to 3.9) for arrhythmia and 0.5% (95% CI 0.2 to 0.8) for pneumonia mortality. Furthermore, the effects of Asian dust were stronger in northern areas close to the Eurasian continent (source of Asian dust). Conclusions Asian dust had adverse effects on circulatory and respiratory mortality independent of PM.

Psychological Factors Including Sense of Coherence and Some Lifestyles are Related to General Health Questionnaire-12 (GHQ-12) in Elderly Workers in Japan

ObjectivesThe number of elderly workers has also been increasing and poor psychological well-being in elderly workers has been reported. The aim of this study is to elucidate the factors that are related to poor psychological well-being in elderly workers.MethodsWe administered General Health Questionnaire-12 (GHQ-12) as an indicator of psychological well-being to 330 male elderly workers in the age range of 50–69, and analyzed different psychological factors, namely sense of coherence (SOC), and physical and lifestyle variables such as blood pressure, serum total cholesterol, smoking frequency, alcohol intake, exercise frequency, and body mass index (BMI) that are related to GHQ-12.ResultsWhen the cut-off point of GHQ-12 was 2/3, 97 workers who showed high GHQ-12 score were classified as one group having poor psychological well-being. A statistically significantly lower SOC score, higher stress score, lower frequency of exercise, higher smoking score and higher BMI, but not longer working hours or higher shift work score in the workers with higher GHQ-12 scores were observed than in the workers with normal GHQ-12 scores. Multiple logistic regression analysis showed that the low SCO score, low frequency of exercise, high smoking frequency and high BMI significantly contributed to the high GHQ-12 score.ConclusionsA low SOC score in elderly workers is assumed to be directly related to poor psychological well-being, or via the development of lifestyle problems such as lack of exercise, obesity, and smoking in elderly workers. This assumption must be confirmed by conducting future intervention studies on lifestyle.

HIV/AIDS surveillance in Japan, 1984-2000.

&NA; The HIV/AIDS surveillance system in Japan, which began collecting data on the number of AIDS patients in 1984 and the number of HIV‐infected persons in 1987, has played an important role in monitoring the trend and magnitude of Japans HIV/AIDS epidemic and its distribution across various population subgroups. However, the system lacks any personal identifiers, making it impossible to eliminate duplication or to track cases for disease progression. It also does not permit the identification of the residence of HIV‐infected persons because the residence of only the reporting physician is documented under the New Infectious Diseases Control Law, effective since April 1, 1999. The number of people with HIV/AIDS in Japan continues to grow. Among youth, sexually transmitted diseases, induced abortion, and sexual activities have shown a marked increase since the mid‐1990s. Behavioral risk of infection for both injection drug users (IDUs) and men who have sex with men (MSM) remains alarmingly high. Accurate monitoring of infection rates is critical to the planning and evaluation of treatment, care and prevention programs. Japan should restructure its HIV/AIDS surveillance system to more accurately monitor the HIV/AIDS epidemic and related risk behaviors.

Perceived Stress, Severity of Asthma, and Quality of Life in Young Adults with Asthma

BACKGROUND People suffering from asthmatic symptoms have a lower quality of life than those without. The aim of this study is to clarify the association of quality of life with the severity of asthma, perceived stress, and other factors such as the comorbidity of allergic diseases among young adults with asthma. METHODS The study participants were 695 asthma patients, aged 20-44 years, from 29 medical centers in Japan. We excluded from the analysis of the result of the study 116 patients with complications of serious diseases, cough-variant asthma or aspirin-intolerant asthma. The patients completed the 8-Item Short-Form Health Survey (SF-8), the Airways Questionnaire 20 (AQ20), and the Japanese version of the Perceived Stress Scale (JPSS) and their doctors also provided clinical information including diagnosis, complications, severity of asthma, and results of pulmonary function and immunological tests. RESULTS There was a weak correlation between the generic quality of life (SF-8) and the disease-specific quality of life (AQ20). The AQ 20 revealed almost no association with the results of pulmonary function and immunological tests, and only a slight association with comorbidity of allergic rhinitis and food allergy. The AQ20 showed a moderate relation with perceived stress (JPSS) but a weak association with the severity of asthma. The multiple logistic models demonstrated that there was no relationship between the severity of asthma and the AQ20 in females, and in the age group of 20-34 years. CONCLUSIONS A major variable related to the disease-specific quality of life was perceived stress, followed by the severity of asthma. Stress management of patients with asthma may improve their quality of life.

Power-Frequency Magnetic Fields and Childhood Brain Tumors: A Case-Control Study in Japan

Background The strength of the association between brain tumors in children and residential power-frequency magnetic fields (MF) has varied in previous studies, which may be due in part to possible misclassification of MF exposure. This study aimed to examine this association in Japan by improving measurement techniques, and by extending measurement to a whole week. Methods This population-based case-control study encompassed 54% of Japanese children under 15 years of age. After excluding ineligible targeted children, 55 newly diagnosed brain tumor cases and 99 sex-, age-, and residential area-matched controls were included in the analyses. The MF exposures of each set of matching cases and controls were measured in close temporal proximity to control for seasonal variation; the average difference was 12.4 days. The mean interval between diagnosis and MF measurements was 1.1 years. The weekly mean MF level was defined as the exposure. The association was evaluated using conditional logistic regression analysis that controlled for possible confounding factors. Results The odds ratios (95% CI) for exposure categories of 0.1 to 0.2, 0.2 to 0.4, and above 0.4 µT, against a reference category of <0.1 µT, were 0.74 (0.17–3.18), 1.58 (0.25–9.83), and 10.9 (1.05–113), respectively, after adjusting for maternal education. This dose-response pattern was stable when other variables were included in the model as possible confounding factors. Conclusions A positive association was found between high-level exposure—above 0.4 µT—and the risk of brain tumors. This association could not be explained solely by confounding factors or selection bias.