Abstract
1. Senile osteoporosis is one of the common causes of morbidity in old people. Its distribution in European and American populations has been deduced from epidemiological studies of its major complications, such as fractures of the vertebrae and the femoral neck. Although there has been some evidence that different population groups differ in their susceptibility to this condition, no demographic study of its prevalence in the white and Bantu races has previously been made.
2. The present paper describes an epidemiological study of femoral neck fractures in the Bantu population of Johannesburg, covering the years 1957-63. The cases were analysed by age and sex, the type of trauma and the level of the fracture. The number of fractures was related to the population at risk; the fracture incidence was expressed both as an age-specific rate and as a standardised rate and compared with fracture rates in European populations. It was found that the fracture rate in the elderly Bantu is less than one-tenth of that in Western European populations, and that males and females are affected equally. It was concluded that senile or post-menopausal osteoporosis is much less pronounced in the Bantu than in white populations.
3. The relationship of these findings to endocrine changes, calcium balance and racial factors is discussed. It is suggested that senile osteoporosis is not caused by a simple calcium deficiency but may be related to an imbalance between calcium intake, absorption and excretion, or a failure of the complex mechanism which normally controls this balance. Whatever the immediate cause, however, race plays an important part in determining the onset and distribution of the condition.
