Overweight may influence breast cancer risk in women with heart disease: WHO study
A WHO study shows postmenopausal women with excess weight and heart disease face a higher risk of breast cancer. Each 5 kg/m² BMI rise raises risk, especially in women with cardiovascular issues. Type 2 diabetes showed no added effect
New Delhi: Excess weight may increase the risk of developing breast cancer among postmenopausal women with cardiovascular disease, according to a study by the World Health Organisation (WHO), published on Monday.
Higher body mass index (BMI) is a known risk factor for breast cancer in postmenopausal women. The study, published in the peer-reviewed journal of the American Cancer Society CANCER, unravels how the risk differs among women with and without cardiovascular disease or type 2 diabetes.
It showed that each 5 kg/m2 increase in BMI was associated with a 31 per cent higher risk of breast cancer in women who developed cardiovascular disease during follow-up and a 13 per cent higher risk in women without cardiovascular disease.
The development of type 2 diabetes did not seem to affect breast cancer risk: women with or without type 2 diabetes had a similarly elevated breast cancer risk related to higher BMI.
“The findings of this study could be used to inform risk-stratified breast cancer screening programmes,” said a team led by Heinz Freisling, from the WHO’s specialised cancer research team, the International Agency for Research on Cancer (IARC).
The team analysed data from the European Prospective Investigation into Cancer and Nutrition (EPIC) and UK Biobank on 168,547 postmenopausal women who did not have, type 2 diabetes, and cardiovascular disease when they agreed to participate. After a median follow-up of 10.7 years in EPIC and 10.9 years in UK Biobank, 6,793 postmenopausal women developed breast cancer.
Further, the study noted that the combination of overweight (BMI≥25 kg/m2) and cardiovascular disease was estimated to lead to 153 more cases of breast cancer per 100,000 people per year than expected. “This study should also inspire future research to include women with a history of cardiovascular diseases in weight loss trials for breast cancer prevention,” Freisling said.
The link between excess weight and increased cancer risk is well established. Being overweight or obese increases your risk for 12 cancers, including uterine, kidney, liver, and colorectal cancer. A recent study, published in the journal Nature Communications, showed that that overweight and obese women are more likely to be diagnosed with larger tumours and more advanced-stage breast cancer.
