From 1997 to 2014, cancer survivors had a significantly faster increase in obesity prevalence compared with adults without a history of cancer, investigators found.

Furthermore, the elevated annual increase in rates of obesity was more pronounced in women, in breast and colorectal cancer survivors, and in non-Hispanic blacks.

Cancer patients may be at an increased risk for weight gain caused by specific cancer treatments such as chemotherapy, steroid modifications, and various hormone therapies, especially in “hormonally and metabolically driven cancers such as breast and colorectal cancer,” wrote Heather Greenlee, ND, PhD, of Columbia University, New York, and her associates (J Clin Oncol. 2016 July 25. doi: 10.1200/JCO.2016.66.4391). “To better inform future research on obesity and cancer survival and to inform the planning and implementation of weight loss interventions in cancer survivors, we compared trends from 1997 to 2014 in obesity prevalence in U.S. adults with and without a history of cancer,” the researchers explained.

Obesity prevalence and trends were evaluated through the National Health Interview Survey , an ongoing cross-sectional survey of the health status, health care access, and behaviors of the U.S. civilian population conducted by the National Center for Health Statistics .

For the current study, surveys from a total of 538,969 adults aged 18-85 years with (n = 32,447) or without (n = 506,522) a history of cancer were analyzed. Participants provided self-reported height and weight measures from which body mass index was calculated. Obesity was defined as a BMI of 30 kg/m2 or higher for non-Asians and 27.5 kg/m2 or higher for Asians. Participants also self-reported sex, race, and cancer history.

Overall, the prevalence of obesity consistently increased from 1997 to 2014. Among cancer survivors, the prevalence of obesity increased from 22.4% to 31.7% while in adults without a history of cancer, prevalence increased from 20.9% to 29.5%.

The annual increase in the rate of obesity was significantly greater in both women and men with a history of cancer (2.9% and 2.8% respectively) compared with those without a history of cancer (2.3% and 2.4%, P less than .001 for all).

The elevated annual increase in rates of obesity was even higher in colorectal (3.1% in women and 3.7% in men) and breast (3.0%) cancer survivors compared with adults without a history of cancer, but was lower in prostate cancer survivors (2.1%; P = .001 for all).

“These findings call for public health planning of effective and scalable weight management and control programs for cancer survivors, especially for breast and colorectal cancer survivors and for non-Hispanic blacks,” the investigators concluded.

The National Cancer Institute funded the study. Dr. Greenlee and one other investigator reported serving in advisory roles for EHE International.

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