Women’s risk of dying of heart disease is always greater than their risk of dying of breast cancer

Editor—Bunker et al put in perspective the risks of women developing and dying of breast cancer.¹ It may, however, be useful to clarify the distinction between the cumulative risk they report—the risk of a woman developing breast cancer before a certain age—and the risk of her developing it in the remainder of her life after a certain age. It is the latter that leads to the oft quoted figure of 1 in 12. In fact, this figure applies only to a young woman (say, aged 30). The remaining lifetime risk then decreases as she survives to older ages (table).

By the time a woman has reached the age of 70 her chance of developing breast cancer during her remaining life is reduced to 1 in 29. Similarly, a woman’s risk of dying of breast cancer during her remaining life decreases as her age increases. This is in contrast to her risk of dying of heart disease (International Classification of Diseases codes 390-429) during her remaining life, which remains at about 1 in 3.3 throughout life: increasing age brings a much more rapid increase in mortality from heart disease than from breast cancer, as Bunker et al show.

Table.

Risk of woman developing or dying of breast cancer or dying of heart disease (International Classification of Diseases codes 390-429) during her remaining life^*

Age (years)	Risk of developing breast cancer	Risk of dying of breast cancer	Risk of dying of heart disease
30	1/12	1/24	1/3.4
40	1/12	1/25	1/3.4
50	1/14	1/26	1/3.4
60	1/18	1/30	1/3.3
70	1/29	1/37	1/3.2
80	1/57	1/48	1/3.2

^*Based on data from Office for National Statistics.^{2 3}