Overwork and cerebrocardiovascular disease in Korean adult workers.
Jang Tae-Won,Kim Hyoung-Ryoul,Lee Hye-Eun,Myong Jun-Pyo,Koo Jung-Wan,Ye Byeong-Jin,Won Jong-Uk
Journal of occupational health
OBJECTIVES:Long work hours and overwork may increase the cardiovascular load of workers. But long work hours and overwork are not the same. Cardiovascular overload from working is dependent on the physical demand of the work and the worker's physical fitness, as well as the working hours. This cross-sectional study was designed to identify the association between overwork and cerebrocardiovascular disease, taking into account the physical demand of work, physical fitness, and work hours. METHODS:Study data were obtained from surveillance of occupational cerebrocardiovascular disease. Questionnaire surveys including general and work-related characteristics were conducted. Maximum acceptable work time was estimated using the physical work demand and physical fitness of the subjects. The overwork index, which was the ratio of maximum acceptable work time and actual work hours of the subjects, was calculated. RESULTS:In the workers with a moderate or high physical demand of work, the adjusted odds ratios for overwork indexes of 1.01-1.20, 1.21-1.50, and >1.50 were 2.679 (95% confidence interval (CI) 1.025-6.999), 3.124 (95% CI 1.111-8.783), and 4.331 (95% CI 1.719-10.908), respectively. CONCLUSIONS:The results indicate that the risk of cerebrocardiovascular disease might be high in the workers with long working hours, high physical demand of work, and poor physical fitness engaged in work with a moderate to high physical work demand. Work hours should be accommodated according to the worker's physical fitness and the physical demand of work, and this could lower the risk of cerebrocardiovascular disease.
Three Cases of Karoshi Without the Typical Pathomorphological Features of Cardiovascular/Cerebrovascular Disease.
Miao Qi,Li Jing,Pan Yu-Peng,Yu Yan-Geng,Zhang Fu,Xiao Ning,Li Dong-Ri
The American journal of forensic medicine and pathology
Karoshi is a term used to describe unexplained sudden death associated with overwork and has become a serious public health issue in China. Cases have occurred in physicians, university professors, engineers in high-tech companies, and blue-collar workers. The mechanisms associated with death by overwork are very complex. According to most researchers, karoshi is considered to be caused by an excessive workload that induces deterioration of underlying hypertension or atherosclerosis. These conditions inevitably lead to death from cardiovascular or cerebrovascular diseases. However, in our own experience, we have found that in some cases, the victims of karoshi were in a chronic state of overwork but without a history of cardiovascular or cerebrovascular diseases. In support of this, we have found that even autopsies have revealed few positive findings except for cardiac hypertrophy. In this article, we report 3 typical cases of karoshi but without the typical pathomorphological features of cardiovascular or cerebrovascular disease.
The Concept, Status Quo and Forensic Pathology of Karoshi.
Yang B F,Shi J Z,Li Q J,Xia L C,Zhang F,Yu Y G,Xiao N,Li D R
Fa yi xue za zhi
Abstract:"Karoshi" originates from Japan's economic take-off period in the 1960s and 1970s. It is generally believed that overwork lead to the accumulation of fatigue, which triggers the outbreak of potential diseases, and results in sudden death. Karoshi causes great harm to both the community and families because it occurs primarily in 30 to 60 year old young adults. Japan put Karoshi into the category of industrial injury for the first time in 2001 and started to undertake a series of studies in the sociological and pathological fields. However, there is a tremendous gap in the forensic pathological diagnosis domain. In China, research on Karoshi started from the 1990s and is closely related to the reform and opening up policy as well as economic development. According to the incomplete statistics, 600 thousand people die from overwork each year in China, the highest in the world. Karoshi has become one of the most serious social problems in China at the present stage, thus a systematic study in the sociology and forensic pathology fields is urgently required. This paper summarizes the past and present status of Karoshi, and puts forward the problems that need attention during the judicial expertise of Karoshi from forensic pathology perspective.
Overwork, stroke, and karoshi-death from overwork.
Acta neurologica Taiwanica
Karoshi, death from over-work, is usually the extreme result of acute cardiovascular events including stroke. Among 203 karoshi cases received worker compensation in Japan, sixty percent died of stroke. Karoshi is a term for social medicine originated form Japan. Literature reviews on karoshi found that long overtime at work, on duty in holidays, attending a new job with no family members around, and working at night shift are risk factors. Work stress increases secretion of catecholamines (epinephrine and norepinephrine) and cortisol which is associated with progression of atherosclerosis and increased risk of cardiovascular diseases and stroke. To avoid long working hours, stress management and treatment of hypertension, diabetes, and hyperlipidemia are key issues in preventing karoshi caused by stroke.
Karoshi May Be a Consequence of Overwork-Related Malignant Arrhythmia.
Xiao Ning,Yang Bo-Fan,Shi Jing-Zhuo,Yu Yan-Geng,Zhang Fu,Miao Qi,Li Dong-Ri
Medical science monitor : international medical journal of experimental and clinical research
BACKGROUND Karoshi, which is sudden death associated with overwork, has become a serious problem in China. Many studies have examined the relationship between cardiovascular risks and karoshi, but there is little evidence that explains the exact mechanism by which overwork induces sudden death. In these cases, there are few obvious positive findings from forensic autopsies except for histories of overwork prior to death. Therefore, we assume that abnormalities, such as cardiac arrhythmia, rather than organic changes are the cause of karoshi. MATERIAL AND METHODS In the present study, the forced swim test (FST) was used to establish models of overwork. The myocardial tissues of SD rats taking FST (1 h per day, for 30 consecutive days) were collected. The arrhythmia-related molecule CX43 as well as its upstream regulation molecule Cav-1 and cSrc were tested by Western blot (WB) and immunohistochemistry (IHC). HE staining and Masson's staining were performed in the myocardium tissue section. RESULTS We observed downregulation of caveolin-1 (Cav1) followed by cSrc activation, resulting in the decrease of connexin43 (Cx43) levels in overwork models. Myocardial interstitial fibrosis, which is associated with electrophysiological aberrances that result in arrhythmia, was also found in the overwork models. CONCLUSIONS These data provide a mechanistic explanation for the speculated link between karoshi and cardiac arrhythmias.