The Diet of Higher Insulinemic Potential Is Not Associated with Worse Survival in Patients with Stage III Colon Cancer (Alliance).

BACKGROUND: Hyperinsulinemia is considered to be important in the development of colon cancer, but few studies have investigated the associations of hyperinsulinemia with colon cancer survival via dietary scores. METHODS: Empirical dietary index for hyperinsulinemia (EDIH) was derived to assess the insulinemic potential of daily diets reflecting the long-term insulin exposure, with higher (more positive) scores indicating higher insulinemic diets. We prospectively estimated the HRs and 95% confidence intervals (CI) to investigate the association of EDIH with disease-free, recurrence-free, and overall survival among patients with stage III colon cancer (1999-2009) enrolled in a randomized adjuvant chemotherapy trial (CALGB 89803). RESULTS: Of 1,024 patients (median follow-up: 7.3 years), 311 died, 350 had recurrences, and 394 had events for disease-free survival. Compared with patients in the lowest quintile of EDIH, the corresponding HRs of patients in the highest quintile for disease-free survival events, cancer recurrence, and overall mortality were 0.80 (95% CI, 0.56-1.15), 0.76 (95% CI, 0.51-1.11), and 0.77 (95% CI, 0.52-1.14). CONCLUSIONS: Higher EDIH was not associated with the risk of colon cancer recurrence or mortality in this population of patients with stage III colon cancer. IMPACT: EDIH, as a measure of dietary insulinemic potential, may be associated with colon cancer risk but not survival in patients with late-stage colon cancer.

Duke Scholars

Author Donna Niedzwiecki Biostatistics & Bioinformatics, Division of Biostatistics