The prevalence of ischaemic heart disease in three rural South African communities

In a population reportedly excessively prone to ischaemic heart disease (IHD) i.e. South African (SA) whites, a 3-community study of 7188 subjects aged 15-64 showed a high prevalence of chest pain by questionnaire (9.5% of males, 7.7% of females) or by ECG findings suggestive of IHD (12.8% males, 6.7% females). In the oldest decile (55-64 years) the prevalence of chest pain and/or ECG findings was 33.4% of males and 26.1% of females. For all ages, 18.4% of males and 13.1% of females were apparently affected. Though females were as likely as males to have a history of chest pain they had fewer ECG findings suggestive of IHD and the history was less likely to have been confirmed by a doctor. The significance of individual findings, assessed by the strength of their associations with symptomatic history and age, appeared to differ between the sexes; though very common, medium S-T depression was not classed as suggestive of IHD in females, while left ventricular hypertrophy was unimpressive in males. Large and medium Q waves, large S-T depression, large and medium T wave inversion were positive in both sexes, but left and right bundle branch block only in males. There was little overlap between a history of chest pain and suggestive ECG findings; however, a previous diagnosis of IHD by the family doctor increased the overlap by up to 6 times.