More than 80 percent of cancer or heart patients surveyed in Japan worked in some form while being hospitalized for treatment, health ministry data shows.

Nearly 82 percent of 1,030 cancer or heart patients surveyed by the ministry said they worked from the hospital, including making job-related reports and preparations to return to their offices.

The results of the ministry's first large-scale survey of its kind, which has not been publicly disclosed, suggest it is difficult for many patients to concentrate on treatment.