South Asian Women Have Higher Breast Cancer Risk Than White Women, UK

South Asian women in Britain have an 8% higher risk of developing breast cancer than British white women, compared to a 45% lower risk ten years ago, researchers from the University of Sheffield reported at the National Cancer Intelligence Network Conference in Brighton on Friday, June 14th.

Study leader, Dr. Matthew Day and team are not sure why breast cancer incidence has increased so rapidly among British South Asian females. They suggest that possibly some lifestyle factors, like having fewer children today, getting pregnant later in life, an increase in screening uptake, oral contraceptive usage, alcohol consumption, and possibly smoking may have had an impact.

Dr. Day and team said, however, that after carrying out their study in Leicester, the evidence is compelling that breast cancer risk for South Asian women in Britain has increased considerably over the last decade.

The researchers had gathered and examined data on 135,000 adult females from a range of ethnic backgrounds from 2000 to 2009. They found that:

• During the period 2000-2004, South Asian women’s risk of developing breast cancer was 45% lower than it was for white women
• By the end of the 2005-2009 period, South Asian women were 8% more likely to develop breast cancer compared to white women

The greatest increase in breast cancer risk was seen among South Asian women aged 65+ years, who by the end of 2009 were found to be 37% more likely to develop breast cancer compared to white women in the same age group.

The study did not examine diabetes prevalence among older South Asian women during the nine-year period to determine whether this might have explained the dramatic increase in breast cancer rates. Post-menopausal women with type 2 diabetes have a 27% higher risk of breast cancer.

The impact of socioeconomic deprivation – during the 2000-2004 period, socioeconomic deprivation was not seen as a risk factor for breast cancer risk, but it was by 2009. This surprised the researchers, because the trend in the rest of the female population was the other way round.

From 2000 to 2009, breast cancer rates for white women remained fairly constant.

Dr. Day said:

“Historically South Asian women, and women in lower socio-economic groups, have been considered at lower risk of developing breast cancer. Based on our study in Leicester, this should no longer be considered the case.

The exact causes behind this change are not clear cut, they could relate to increases in screening uptake among these groups of women, which have in the past been shown to be lower than in other groups . . . . . Or they could be due to changes in lifestyle factors, like having fewer children and having them later in life, increased use of oral contraceptives, and increased smoking and alcohol intake – factors linked to increased breast cancer risk across the board.”

Clinical Lead at Public Health England’s National Cancer Intelligence Network, Dr Mick Peake, said “The results of the Leicester study should assist public health services to both plan for, and respond to, the changing risk profile of breast cancer in the population, particularly with regards Asian women who for a long time have been another group whose attendance rate for screening has been low. At the individual level, if women are concerned about breast cancer, they should speak to their GP.”