Prostate cancer and subsequent nutritional outcomes: the role of diagnosis and treatment.

PURPOSE: To comprehensively explore the role of a prostate cancer diagnosis and its treatment to several outcomes including diet, Hemoglobin A1c, and weight status, in a large, nationally representative, cross-sectional study.
METHODS: This analysis used five cross sections from the publicly available National Health and Nutrition Evaluation Survey (NHANES) from 2001 to 2010. A sample of 289 men with a history of prostate cancer was matched to a comparison group of 655 men with elevated prostate-specific antigen (> 4 ng/mL) but no reported diagnosis of prostate cancer. Analyses were stratified by diabetic or pre-diabetes status and treatment including surgery, radiotherapy, or both. Outcomes of interest included several broad macronutrient categories, HbA1c, body mass index, and obesity status. Multivariate regression analyses were conducted to clarify the associations of a prostate cancer diagnosis with these outcomes. Demographic and socioeconomic factors, including age, education, race, income, and marital status, were controlled for in all models.
RESULTS: The clinical and demographic characteristics were relatively well balanced between the "at risk" comparison group and the group of men diagnosed with prostate cancer. Diabetic or pre-diabetic men diagnosed with prostate cancer were more likely to be obese (p < 0.05) and have a higher BMI (p < 0.10). On multivariate analysis, compared to controls, men with prostate cancer treated with surgery and radiation therapy were predicted to have a higher BMI (p < 0.01) and were more likely to be obese (p < 0.05). These findings were largely driven by the diabetic and pre-diabetic sample. Further diabetics and pre-diabetics with prostate cancer treated with both radiation and surgery were predicted to consume an average of 72 and 59 more daily grams of carbohydrates and sugar, respectively, compared to controls (p < 0.05).
CONCLUSION: Men with prostate cancer report fewer behaviors and outcomes consistent with optimal glycemic management including a higher BMI, and in diabetics and pre-diabetics, increased carbohydrate sugar consumption. Men with more intense treatment including surgery and radiotherapy appeared to be more likely to be obese and make poorer dietary carbohydrate and sugar choices compared to men without prostate cancer. IMPLICATIONS FOR CANCER SURVIVORS: Men treated for prostate cancer have, on average, very long survivorship periods and are susceptible to diabetes and its complications. Interventions designed to improve diabetes awareness and self-management, especially weight and dietary sugar control, may be useful in this population.