People who were overweight during early adulthood and gained additional weight to become obese later in life are at an increased risk for esophageal and gastric cardia adenocarcinomas, according to a pooled analysis of two studies published in the British Journal of Cancer.
Compared with normal-weight individuals, those people who had a body mass index (BMI) of 25 kg/m2 or greater at age 20 had an almost 80% increased risk for esophageal cancer and a 60% increased risk for gastric cancer. In addition, an overweight BMI at age 20 progressing to obesity (BMI of 30 or greater) by age 50 was associated with almost three times the risk for esophageal cancer (hazard ratio [HR], 2.90; 95% CI, 1.67–5.04) and four times the risk for gastric adenocarcinoma (HR, 4.07; 95% CI, 2.32–7.15).
“This study highlights how weight gain over the course of our lives can increase the risk of developing these two cancer types, both of which have extremely poor survival,” said study researcher Jessica L. Petrick, PhD, MPH, of the division of cancer epidemiology and genetics at the National Cancer Institute, in a press release. “Carrying excess weight can trigger long-term reflux problems and heartburn that can lead to cancer. It can also change the levels of sex hormones, such as estrogen and testosterone, cause levels of insulin to rise, and lead to inflammation, all of which are factors that have been associated with increased cancer risk.”
Petrick and colleagues pooled data from two prospective cohort studies, the NIH-AARP Diet and Health Study and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Together these studies included data on 409,796 people. At baseline, participants reported height and weight at ages 20 and 50, and current age.
Data showed that those participants who reported a BMI of greater than 25 at age 20 had significantly increased risk for both esophageal (HR, 1.76; 95% CI, 1.35–2.29) and gastric adenocarcinoma (HR, 1.62; 95% CI, 1.16–2.25) compared with normal-weight individuals.
Additionally, the researchers found that a weight change of 15 kg or more during early adulthood (age 20 to 50) was associated with modest increased risk for esophageal cancer (HR, 1.26; 95% CI, 0.98–1.62). However, this risk increased when a change of weight of 15 kg occurred after age 50 (HR, 1.57; 95% CI, 1.19–2.08). An overall lifetime weight change of 20 kg from age 20 to current age was strongly associated with risk for esophageal cancer (HR, 1.97; 95% CI, 1.43–2.73).
“This analysis of two large, mature US cohorts provide evidence that early adulthood overweight and obesity are strong risk factors for esophageal adenocarcinoma and gastric cardia adenocarcinoma, and that large weight gains over the life course confer high risks for these malignancies,” the researchers wrote. “These results indicate that weight gain during adulthood should be avoided to reduce the risk of esophageal adenocarcinoma and gastric cardia adenocarcinoma, and underscores the potential of weight control programs for reducing the incidence of these highly lethal cancers.”