Men are seven times more likely to die suddenly than women, a new study shows.
The study of death reports, undertaken by University of Hong Kong cardiologists, also found 90 per cent of otherwise healthy people who died suddenly had undiagnosed coronary heart diseases.
Dr Kathy Lee Lai-fun, an honorary clinical assistant professor in the cardiology division, said men suffered coronary heart disease more often than women.
Men smoked and ate unhealthy food more often and lacked women's protective hormones, she said.
Women were more health conscious and sought medical advice if they felt ill, Dr Lee said.
Of the 5,000 coroner's reports from 1997 studied, 1,204 were cases of 'sudden death', defined as unexpected death within an hour of the onset of symptoms or someone dying alone with no prior symptoms and discovered within 24 hours. Deaths due to poisoning, accident, suicide or crime were not counted.
'Sudden deaths in these victims were related to cardiovascular disease in 89 per cent of the 1,204 cases,' Dr Lee said.
While the elderly suffered most sudden deaths - 52 per cent - the study found that 39 per cent were aged 41 to 65. Forty-two per cent of deaths occurred between 8pm and 8am, 78 per cent at home and 33 per cent during sleep.
Professor Lau Chu-pak, chief of the cardiology division at the university, said that the risk of sudden death could be minimised by knowing the family history of heart problems.