MAJOR cities in China are required to set up hotlines to help people suffering from mental stress, the Ministry of Health said last week. Provinces in the more affluent eastern part of the country should launch the hotlines, which are to be maintained by professional psychological consultants, by the end of this year. Chinese are experiencing increasing psychological pressure as a result of a faster pace of life and rising competition. Based on a study done by the Ministry of Health in 1993, the latest research by the ministry, experts believe there are 200 million Chinese suffering from various kinds of mental stresses.