Duration of Obesity Increases Cancer Risk in Women

Duration and degree of being overweight impacts cancer risk in postmenopausal women.

A recent study found that a long duration of adult obesity can increase the risk of developing certain cancers in women.

Overweight and obesity have long been associated with diseases such as type 2 diabetes and cardiovascular disease. Cancers linked to high body mass index (BMI) are breast, esophageal, pancreatic, colorectal, renal, endometrial, ovarian, and gallbladder.

Researchers in a study published by PLOS Medicine included 73,913 postmenopausal women also enrolled in the Women’s Health Initiative study. No patients had cancer at the start of the current study.

They examined the dose-response relationship between overweight duration and cancer. Patient BMIs were calculated on at least 3 occasions during the duration of the study.

Only 40% of study participants were never considered overweight. Approximately 60% were overweight and nearly half of those patients were also obese.

These patients were more likely to be younger at baseline, have less education, and more likely to be African American compared with non-overweight participants, according to the study. Researchers found that 6301 patients developed invasive obesity-related cancer.

Overall, they discovered that a longer duration of overweight was associated with an increased incidence of cancer (hazard ratio [HR] per 10-y increment: 1.07, 95% CI 1.06—1.09). The strongest associations between overweight duration risk and obesity-related cancer was endometrial cancer (HR 1.17, 95% CI 1.12–1.22) and kidney cancer (HR 1.16, 95% CI 1.07–1.26), according to the study.

For every 10-years of overweight, breast and endometrial cancer risk increased 5% and 17%, respectively. Intensity of overweight caused the risk to increase to 8% and 37%.

They discovered that higher incidences of breast and colon cancers were also associated with longer durations of overweight and obesity, according to the study. Researchers also found that the risk of breast and endometrial cancer were drastically decreased among patients using postmenopausal hormones.

They caution that their findings may be limited since they relied on retrospective self-reports from patients. Researchers concluded that reducing overweight duration could reduce cancer risk, making obesity prevention very important as well.

Healthcare providers should view obesity management as a form of cancer prevention regardless of age, the study concluded.