Background Observationally, testosterone falls with age among men and ischaemic heart disease (IHD) increases with age, so testosterone is commonly assumed to protect against IHD. Here we examined whether IHD mortality rates among men increased faster with age in the USA than China, where testosterone in men remains stable throughout adulthood, and also whether the increase with age in mortality rates for IHD is faster than for other causes of death.

Methods Age-specific mortality rates from all causes, IHD, pneumonia and prostate cancer for men in the USA and China from 1991 to 1995 were obtained from the WHO, and considered in age groups because of non-linearity.

Results The risk of death from IHD in US men increased with age at the same rate as the risk of death from any cause. In China, the risk of death from IHD increased with age faster than the risk of death from any cause.

Conclusion The data are not consistent with the assumption that a fall in testosterone with age causes IHD.