Variations in mortality of the coloured, white and Asian population groups in the RSA, 1978-1982. Part IV. Respiratory diseases.

Respiratory diseases are major causes of death in South Africa. The reported mortality rates (MRs) for: (i) pneumonia and influenza; (ii) chronic obstructive lung disease and allied conditions; (iii) pulmonary tuberculosis; and (iv) carcinoma of the lung and bronchus over a 5-year period are examined in relation to age, sex, ethnic group and year. Such data have not previously been reported in South Africa. MRs for all respiratory diseases (except lung carcinoma) were substantially higher in coloureds than in whites or Asians. In each ethnic group and for each disease category, MRs for males were higher than for females, especially in those over the age of 24 years. For all, except lung carcinoma, MRs were highest at the extremes of life. Changes in respiratory disease MRs over the 5-year period were examined by calculating the age standardised MRs for each condition in each of the 5 years. There was a clear decline in the MR for pneumonia over this period in all groups. The MR for chronic obstructive pulmonary disease rose in all groups, except Asian females. Similarly, the MR for carcinoma increased in all groups, except white females. The MR for tuberculosis was highest in coloured males (10 times greater than in Asian males and 100 times greater than in white females). The pattern of respiratory disease MRs in white South Africans is very similar to that in the USA, whereas in coloureds MRs for infectious diseases remain high and are added to by the burden of cigarette smoking-related deaths.