Tsutomu Hoshuyama

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.

Global magnitude of reported and unreported mesothelioma.

Background Little is known about the global magnitude of mesothelioma. In particular, many developing countries, including some with extensive historical use of asbestos, do not report mesothelioma. Objectives We estimated the global magnitude of mesothelioma accounting for reported and unreported cases. Methods For all countries with available data on mesothelioma frequency and asbestos use (n = 56), we calculated the 15-year cumulative number of mesotheliomas during 1994–2008 from data available for fewer years and assessed its relationship with levels of cumulative asbestos use during 1920–1970. We used this relationship to predict the number of unreported mesotheliomas in countries for which no information on mesothelioma is available but which have recorded asbestos use (n = 33). Results Within the group of 56 countries with data on mesothelioma occurrence and asbestos use, the 15-year cumulative number of mesothelioma was approximately 174,300. There was a statistically significant positive linear relation between the log-transformed national cumulative mesothelioma numbers and the log-transformed cumulative asbestos use (adjusted R2 = 0.83, p < 0.0001). Extrapolated to the group of 33 countries without reported mesothelioma, a total of approximately 38,900 (95% confidence interval, 36,700–41,100) mesothelioma cases were estimated to have occurred in the 15-year period (1994–2008). Conclusions We estimate conservatively that, globally, one mesothelioma case has been overlooked for every four to five reported cases. Because our estimation is based on asbestos use until 1970, the many countries that increased asbestos use since then should anticipate a higher disease burden in the immediate decades ahead.

Return to Work After Stroke A Follow-up Study

BACKGROUND AND PURPOSE Few studies have reported the longitudinal trend of return to work after stroke. The purpose of our study was to evaluate the longitudinal trend of proportion of patients who return to work after stroke and further to examine the predictors of return to work while taking follow-up periods into consideration. METHODS We conducted a retrospective cohort study on the association between characteristics of stroke patients at admission and return to work after first stroke, taking length of follow-up period into consideration (n = 183). The patients were all younger than 65 years and were working at the time of their stroke. A follow-up questionnaire evaluated return to work and related information. Data were analyzed using the Kaplan-Meier method for curves of the proportion of return to work and Coxs proportional hazards model for odds ratios of return to work. RESULTS The curve of proportion of return to work had two steep slopes, and the proportion was at a maximum at 18 months from patient admission. The adjusted odds ratios of return to work for patients with normal muscle strength versus severe weakness, without apraxia versus with apraxia, and with white-collar versus blue-collar occupations were 5.16 (P < .05), 4.16 (P < .05), and 1.43 (.05 < P < .10), respectively. CONCLUSIONS The increase of proportion of return to work after stroke was nonlinear, and this trend was referable to the social security systems available to the patients included in this study. Normal muscle strength and absence of apraxia were significant predictors of return to work after stroke. White-collar occupation showed a tendency to promote return to work.

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.

Mortality of Iron-Steel Workers in Anshanl China: A Retrospective Cohort Study

Abstract Foundry workers have increased mortality and morbidity risks from numerous causes, including various cancers. A retrospective Chinese iron-steel cohort study was conducted to examine the mortality effects of exposure to foundry work. Standardized mortality ratios (SMRs) and standardized rate ratios (SRRs) were calculated to evaluate mortality risks among male workers with exposure to 15 hazardous factors, acljusting for confounders. During 14 years of follow-up, 13,363 of 121,846 male workers died. SMR analysis showed a healthy-worker effect in comparison with the general population. SRR analysis showed increased risks for all causes, all neoplasms, and others among the exposed workers compared with nonexposed blue-collar workers. Combined exposure to polycyclic aromatic hydrocarbons and two or more dusts increased the risks of lung cancer (SRR = 654; 95% CI: 113–3,780) and other malignancies. Foundry work has adverse health effects, including carcinogenic risks.

Clinical factors predictive of encephalitis caused by Angiostrongylus cantonensis.

Angiostrongylus cantonensis is mainly caused eosinophilic meningitis in humans, whereas a minority of patients develop encephalitic angiostrongyliasis (EA). EA is an extremely fatal condition, and the clinical factors predictive of EA have never been reported. A comparison study was conducted in a hospital situated in an endemic area of Thailand. We enrolled 14 and 80 angiostrongyliasis patients who developed encephalitis and meningitis, respectively. Logistic regression analysis was used to assess the clinical variables predictive of encephalitis. Age (adjusted odds ratio [OR], 1.22; 95% confidence interval [CI], 1.05-1.42), duration of headache (adjusted OR, 1.26; 95% CI, 1.03-1.55), and fever > 38.0 degrees C (adjusted OR, 37.05; 95% CI, 1.59-862.35) were identified as statistically significant factors for EA prediction. Elderly patients with angiostrongyliasis experiencing fever and prolonged headaches were at the highest risk of developing EA.

Respiratory symptoms among residents of a heavy-industry province in China: Prevalence and risk factors

OBJECTIVE In China, significant levels of environmental pollution, substandard worksite quality and high rates of smoking predispose the population to potentially high risks of respiratory illnesses and other diseases. We assessed the prevalence of respiratory symptoms and their risks in relation to personal, occupational and environmental risk factors in a heavy-industry province of northeastern China. METHODS Lifestyle, health, residential and occupational data were obtained in 2002 from 31,704 adults of six cities in Liaoning, China, using self-assessment questionnaires. General linear and multi-level models were used to evaluate prevalence rates and risks of respiratory symptoms, related to both individual and combined exposures to environmental and occupational risk factors. RESULTS The crude prevalence rates (PRs) for persistent cough, persistent phlegm, wheeze and asthma were 2.3, 3.8, 2.1 and 1.0%, respectively. The odds ratios (ORs) of all four respiratory symptoms examined were increased by: smoking (ORs from 2.06 to 5.02), occupational dust (ORs from 1.35 to 1.72), occupational gas (ORs from 1.48 to 1.72) and presence of irritating smoke during cooking (ORs from 1.54 to 2.22). An index combining proximity of residence to road, factory or chimney, indoor coal use and presence of irritating smoke during cooking was associated with up to 3.9-fold increased risks of all symptoms. Increasing values of each risk factor were generally associated with dose-response trends in prevalence rates and risks (all p for trend <0.01). CONCLUSION The crude PRs of symptoms were lower than those reported by European and American studies but closer to those of previous Chinese studies. The risks of respiratory symptoms in this population were increased by smoking, occupational exposures to dust and gas, and combined residence-related exposures such as living close to a main road, factory or chimney, indoor coal use and the presence of irritating smoke during cooking, among other risk factors.

Association between location of the lesion and discharge status of ADL in first stroke patients

We investigated the relationship between the location of the lesion in the brain and discharge status of activities of daily living measured by Barthel index in 112 first-stroke patients who had survived to discharge. Physiatrists and radiologists determined the location of the lesion based on neuroanatomic classification of findings detected by head-computed tomography (CT) of the patients. A stepwise regression analysis showed that only one selected location, the right parietal lobe lesion, was negatively associated with discharge Barthel index (R2 = 0.04). However, low R2 indicated that factors other than CT findings could also influence discharge Barthel index, and thus location of the lesion detected by head CT should be considered as adjunctive on prediction of discharge status.

Nationwide Survey of Work Environment, Work-Life Balance and Burnout among Psychiatrists in Japan

Background Psychiatry has been consistently shown to be a profession characterised by ‘high-burnout’; however, no nationwide surveys on this topic have been conducted in Japan. Aims The objective of this study was to estimate the prevalence of burnout and to ascertain the relationship between work environment satisfaction, work-life balance satisfaction and burnout among psychiatrists working in medical schools in Japan. Method We mailed anonymous questionnaires to all 80 psychiatry departments in medical schools throughout Japan. Work-life satisfaction, work-environment satisfaction and social support assessments, as well as the Maslach Burnout Inventory (MBI), were used. Results Sixty psychiatric departments (75.0%) responded, and 704 psychiatrists provided answers to the assessments and MBI. Half of the respondents (n = 311, 46.0%) experienced difficulty with their work-life balance. Based on the responses to the MBI, 21.0% of the respondents had a high level of emotional exhaustion, 12.0% had a high level of depersonalisation, and 72.0% had a low level of personal accomplishment. Receiving little support, experiencing difficulty with work-life balance, and having less work-environment satisfaction were significantly associated with higher emotional exhaustion. A higher number of nights worked per month was significantly associated with higher depersonalisation. Conclusions A low level of personal accomplishment was quite prevalent among Japanese psychiatrists compared with the results of previous studies. Poor work-life balance was related to burnout, and social support was noted to mitigate the impact of burnout.