Trends in Obesity Prevalence in Adults With a History of Cancer: Results From the US National Health Interview Survey, 1997 to 2014.

PURPOSE: Obesity after a diagnosis of specific cancers has been associated with worse prognosis. We examined the trend in obesity prevalence among cancer survivors in the United States in the past two decades and compared trends with those of adults without a history of cancer.

PATIENTS AND METHODS: This was a population-based nationally representative sample of 538,969 noninstitutionalized US adults 18 to 85 years old with and without a history of cancer who participated in annual cross-sectional National Health Interview Surveys from 1997 to 2014. Obesity was defined as body mass index ≥ 30 kg/m(2) for non-Asians and body mass index ≥ 27.5 kg/m(2) for Asians.

RESULTS: Among 32,447 cancer survivors identified, the most common cancer diagnoses were breast (n = 6,948), prostate (n = 3,984), and colorectal (n = 2,546). From 1997 to 2014, the prevalence of obesity increased from 22.4% to 31.7% in cancer survivors and from 20.9% to 29.5% in adults without a history of cancer (P for trend < .001, both groups). Over this period, the estimated rate of annual increase in obesity prevalence was higher in women and men with a history of cancer compared with those without a history of cancer (all P for interaction < .001). The estimated rate of annual increase in obesity prevalence was 3.1% in female and 3.7% in male colorectal cancer survivors, 3.0% in breast cancer survivors, and 2.1% in prostate cancer survivors (all P < .001). In subgroup analyses, populations with the highest rates of increasing obesity burden were colorectal cancer survivors, breast cancer survivors, and non-Hispanic blacks.

CONCLUSION: From 1997 to 2014, obesity increased more rapidly among adult cancer survivors compared with the general population. Colorectal and breast cancer survivors and non-Hispanic blacks were identified as being at the highest risk for obesity.