Toshiaki Higashi

Ecological association between asbestos-related diseases and historical asbestos consumption: an international analysis

BACKGROUND The potential for a global epidemic of asbestos-related diseases is a growing concern. Our aim was to assess the ecological association between national death rates from diseases associated with asbestos and historical consumption of asbestos. METHODS We calculated, for all countries with data, yearly age-adjusted mortality rates by sex (deaths per million population per year) for each disease associated with asbestos (pleural, peritoneal, and all mesothelioma, and asbestosis) in 2000-04 and mean per head asbestos consumption (kg per person per year) in 1960-69. We regressed death rates for the specified diseases against historical asbestos consumption, weighted by the size of sex-specific national populations. FINDINGS Historical asbestos consumption was a significant predictor of death for all mesothelioma in both sexes (adjusted R2=0.74, p<0.0001, 2.4-fold [95% CI 2.0-2.9] mortality increase was predicted per unit consumption increase for men; 0.58, p<0.0001, and 1.6-fold [1.4-1.9] mortality increase was predicted for women); for pleural mesothelioma in men (0.29, p=0.0015, 1.8-fold [1.3-2.5]); for peritoneal mesothelioma in both sexes (0.54, p<0.0001, 2.2-fold [1.6-2.9] for men, 0.35, p=0.0008, and 1.4-fold for women [1.2-1.6]); and for asbestosis in men (0.79, p<0.0001, 2.7-fold [2.2-3.4]). Linear regression lines consistently had intercepts near zero. INTERPRETATION Within the constraints of an ecological study, clear and plausible associations were shown between deaths from the studied diseases and historical asbestos consumption, especially for all mesothelioma in both sexes and asbestosis in men. Our data strongly support the recommendation that all countries should move towards eliminating use of asbestos.

Periodontal Disease and Incident Diabetes a Seven-year Study

Diabetes is associated with a high prevalence of periodontal disease, but little is known about the effects of periodontal disease on incident diabetes. In total, 5848 non-diabetic individuals aged 30-59 yrs who completed a health examination were analyzed in this study. They were divided into three categories: no pathological pockets, moderate periodontitis, or severe periodontitis. Incident diabetes was defined as newly diagnosed cases with fasting plasma glucose > 125 mg/dL. Cox proportional hazards models estimated the effect of periodontitis on incident diabetes during a seven-year follow-up period. Moderate and severe periodontitis was significantly associated with an increased risk of diabetes in unadjusted analyses, but the magnitude of the association decreased after full adjustment [hazard ratio (HR) = 1.00, 95% confidence interval (95% CI) = 0.77-1.30 and HR = 1.28, 95% CI = 0.89-1.86, respectively]. Our findings do not indicate an apparent association between periodontitis and incident diabetes, although there was a tendency for increased risk.

Recent Mortality from Pleural Mesothelioma, Historical Patterns of Asbestos Use, and Adoption of Bans: A Global Assessment

Background In response to the health risks posed by asbestos exposure, some countries have imposed strict regulations and adopted bans, whereas other countries have intervened less and continue to use varying quantities of asbestos. Objectives This study was designed to assess, on a global scale, national experiences of recent mortality from pleural mesothelioma, historical trends in asbestos use, adoption of bans, and their possible interrelationships. Methods For 31 countries with available data, we analyzed recent pleural mesothelioma (International Classification of Diseases, 10th Revision) mortality rates (MRs) using age-adjusted period MRs (deaths/million/year) from 1996 to 2005. We calculated annual percent changes (APCs) in age-adjusted MRs to characterize trends during the period. We characterized historical patterns of asbestos use by per capita asbestos use (kilograms per capita/year) and the status of national bans. Results Period MRs increased with statistical significance in five countries, with marginal significance in two countries, and were equivocal in 24 countries (five countries in Northern and Western Europe recorded negative APC values). Countries adopting asbestos bans reduced use rates about twice as fast as those not adopting bans. Turning points in use preceded bans. Change in asbestos use during 1970–1985 was a significant predictor of APC in mortality for pleural mesothelioma, with an adjusted R2 value of 0.47 (p < 0.0001). Conclusions The observed disparities in global mesothelioma trends likely relate to country-to-country disparities in asbestos use trends.

Ecological Relationship between Mesothelioma Incidence/Mortality and Asbestos Consumption in Ten Western Countries and Japan.

Ecological Relationship between Mesothelioma Incidence/Mortality and Asbestos Consumption in Ten Western Countries and Japan: Ken Takahashi, et al. Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health—The objective of the present study was to evaluate the ecological relationship between mesothelioma incidence/mortality and per capita asbestos consumption in ten Western countries and Japan. The two national indices used to assess the geographical correlation were the most recent incidence/mortality rate of mesothelioma for the population over 15 years of age, and the per capita asbestos consumption rate of approximately 10‐25 years ago for the population of ail ages at that time. Among the ten Western countries, a clear linear relationship was shown between the mesothelioma incidence/mortality rate and the preceding per capita asbestos consumption rate with the Spearman correlation coefficient at 0.70 (p=0.03), and R2‐value at 66%. However, the data‐point for Japan was situated apart from the linear relationship due to the lower mesothelioma mortality rate, and when combined with other Western countries, the significant relationship diminished. It is possible that the asbestos consumption curve for Japan in past years lagged behind that for the Western countries and the cumulative exposure effect has not yet reached the level that can be expected from other Western countries.

An Epidemiological Study of Work-related Violence Experienced by Physicians who Graduated from a Medical School in Japan

An Epidemiological Study of Work‐related Violence Experienced by Physicians who Graduated from a Medical School in Japan: Mayuri Arimatsu, et al. Department of Work Systems and Health, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Japan—Healthcare workers are at high risk of being victim of verbal and physical violence perpetrated by patients. There are only a few studies on work related violence among physicians. The aim of this study was to determine how prevalent work‐related violence against physicians is and whether gender, age, specializations and workplaces are associated with verbal and physical violence against physicians in Japan. A questionnaire was mailed to all the 1,705 physicians who had graduated from one medical school in Japan and had practiced for a minimum of 3 yr by the time of this study. The verbal and physical violence experienced by physicians at the hands of their patients and/or clients in the last 6 months preceding this study were collected. We defined ‘verbal violence’ as ‘any threatening statement or complaint’ while ‘physical violence’ referred to ‘the attempted or actual exercise by persons of any physical force so as to cause injury to a physician’. Multiple logistic regression analysis was used to determine the independent contribution of each factor with violence. A total of 540 men and 158 women responded. The adjusted response rate was 41.8%. Among the participants, 168 (24.1%) physicians had experienced verbal violence and 15 (2.1%) physicians had experienced physical violence in the prior 6 months. Verbal violence was positively associated with physicians who were under 30 yr old (odds ratio [OR] = 2.1; 95% confidence interval [CI], 1.0–4.1 for 27–29 yr old) and, psychiatry (OR, 2.4; 95% CI, 1.1–5.4). Physical violence was significantly associated with women (OR, 3.8; 95% CI, 1.1–13.5), specializations such as emergency and anesthesiology (OR, 18.9; 95% CI, 2.8–126.1), and psychiatry (OR, 7.6; 95% CI, 1.6–35.4). There was a considerable number of physicians exposed to violence. Younger physicians and psychiatrists are likely to be exposed to verbal violence. Female physicians, psychiatrists, and emergency physicians are likely to be exposed to physical violence. Education on avoiding from violence should be provided for physicians early in their career.

MUC1 mucin mRNA expression in stage I lung adenocarcinoma and its association with early recurrence

BACKGROUND MUC1 is a membrane-bound mucin with an extensively O-glycosylated core protein and is developmentally regulated and aberrantly expressed by carcinomas. A high level of MUC1 mucin expression and secretion is associated with high metastatic potential and a poor prognosis. We studied the expression of MUC1 messenger ribonucleic acid (mRNA) in stage I lung adenocarcinoma by reverse transcriptase-polymerase chain reaction and examined its correlation with early recurrence. METHODS The expression of MUC1 mRNA, in surgical specimens from 33 patients with stage I lung adenocarcinoma was determined by reverse transcriptase-polymerase chain reaction. The MUC1 and beta-actin sequences were subsequently coamplified to analyze the semiquantitative determination by polymerase chain reaction. The ratio of MUC1 to beta-actin product was used for further analysis. RESULTS An analysis of the disease-free survival (median follow-up, 33.4 months) revealed that a high expression of MUC1 was associated with early recurrence (p = 0.0191). Six of the 33 patients had recurrence within 2 years after operation. The recurrence sites suggested hematogenic metastasis. CONCLUSIONS Our results indicate that MUC1 mRNA level may be useful as a marker of early recurrence in stage I lung adenocarcinoma.

Effect of lead on cardiac parasympathetic function

SummaryA cross-sectional survey was performed on 172 male, lead exposed workers to clarify the effects of lead on the cardiac autonomic nervous system expressed as the decrease of R-R interval variation on an electrocardiogram and to obviate the dose-effect relationship between blood-lead level (Pb-B) and the degree of the decrease. For 132 workers who were exposed to lead for more than one year and whose Pb-B levels were relatively stable (Pb-B variation less than 20 μg/dl during recent one year), a significant dose-related decrease of R-R interval variation during deep breathing was observed. Age-adjusted R-R interval variation during deep breathing in those whose Pb-B were 30 μg/dl or above was significantly decreased compared with those whose Pb-B levels were 20 μg/dl or below. This decrease was observed more clearly in younger workers. These results suggest that an effect on autonomic nervous system expressed as decrease of R-R interval variation during deep breathing might be one of the earliest effects of lead exposure.

Physician Job Satisfaction and Working Conditions in Japan

Physician Job Satisfaction and Working Conditions in Japan: Koji Wada, et al. Department of Preventive Medicine and Public Health, Kitasato University School of Medicine

National use of asbestos in relation to economic development.

Background National disparities in asbestos use will likely lead to an unequal burden of asbestos diseases. Objectives As economic status may be linked to asbestos use, we assessed, globally, the relationship between indicators of national economic development and asbestos use. Methods For the 135 countries that have ever used asbestos, per capita asbestos use (kilograms per capita per year) was compared with per capita gross domestic product (GDP) in 1990 Geary–Khamis dollars (GKD) for the period 1920–2003. Countries were grouped into three income levels (high, middle, and low) that were adapted from the 2003 World Bank categories. Results The historical pattern of asbestos use followed the environmental Kuznets curve in which use by high-income countries peaked when incomes attained 10,000–15,000 GKD and essentially ceased at income levels over 20,000 GKD. Currently, middle- and low-income countries are increasing their use of asbestos, closely following the paths once traced by higher income countries. Conclusions Developing countries have the opportunity to eliminate asbestos use sooner than high-income countries and thus reduce the future burden of asbestos diseases.

Expression of Heme Oxygenase-1 in the Lungs of Rats Exposed to Crystalline Silica

Expression of Heme Oxygenase‐1 in the Lungs of Rats Exposed to Crystalline Silica: Hiroko Nagatomo, et al. Department of Occupational Pneumology, Institute of Industrial and Ecological Sciences, University of Occupational and Environmental Health—Oxidative stress is thought to be the pathogenesis of pulmonary fibrosis induced by particles, and heme oxygenase‐1 (HO‐1) protects lung tissue against oxidative stress. We hypothesized that HO‐1 is also associated with oxidative lung injury caused by exposure to particles. The present study was conducted to investigate the time course of HO‐1 expression of lungs exposed to crystalline silica in vivo. Male Wistar rats were administered 1 mg or 2 mg of crystalline silica suspended in saline by a single intratracheal instillation and were sacrificed at 3 d, 1 wk, 1 month, 3 months and 6 months of recovery time. The expression of HO‐1 was observed by western blot analysis and immunostaining. Protein levels of HO‐1 were increased compared to the controls at 3 d, and from 1 month to 6 months following intratracheal instillation of 2 mg of crystalline silica. The levels of HO‐1 were increased compared to the controls from 1 month to 6 months following intratracheal instillation of 1 mg of crystalline silica. Many HO‐1 positive cells were found particularly in the alveolar macrophages during immunostaining. These findings suggest that HO‐1 is related to lung injury arising from exposure to crystalline silica.