Karoshi (pronounced /karo:Si/), which can be translated quite literally from the Japanese as "death from overwork", is occupational sudden death. The major medical causes of karoshi deaths are heart attack and stroke due to stress.
The first case of karoshi was reported in 1969 with the death from a stroke of a 29-year-old married male worker in the shipping department of Japan's largest newspaper company. It was not until the latter part of the 1980s, however, when several high-ranking business executives who were still in their prime years suddenly died without any previous sign of illness, that the media began picking up on what appeared to be a new phenomenon. This new phenomenon was quickly labelled karoshi, and once it had a name and its symptoms were described and popularized, it was immediately seen as a new and serious menace for people in the work force. In 1987, as public concern increased, the Japanese Ministry of Labour began to publish statistics on karoshi.
Usually, Japan's rise from the devastation of World War II to economic prominence in the post-war decades has been regarded as the trigger for what has been called a new epidemic. It was recognized that employees cannot work for up to twelve hours a day six or seven days a week, year after year, without suffering physically as well as mentally.
Meanwhile, death-by-overwork lawsuits have been on the rise in Japan, with the deceased person's relatives demanding compensation payments. However, before compensation can be awarded, the labour inspection office must acknowledge that the death was work-related.
In Korea, where a Confucian-inspired work ethic involves much of the adult populace, both male and female, in a six-day workweek with long hours, this phenomenon is known as "gwarosa" (Hangul, ???).
Adapted from http://en.wikipedia.org/wiki/Karoshi