"People who have a previous history of affective or psychiatric states should be cautious about flying without getting some preventive treatment from a consulting psychiatrist," he said. The research, to be published in the journal Comprehensive Psychiatry , involved 81 patients from North and South America, the East Asia and Australia - who had travelled eastwards across at least seven time zones - and 71 from Europe, whose journeys covered at most three time zones. Twenty eight per cent of the first group suffered symptoms of a psychotic episode or affective disorder within seven days of landing having had no previous psychiatric history or having been in full remission for at least a year prior to the flight. - www.timeshighereducation.com