Data from Calcium Intake and Survival after Colorectal Cancer Diagnosis

Abstract

<div>AbstractPurpose:<p>Although evidence suggests an inverse association between calcium intake and colorectal cancer incidence, the influence of calcium on survival after colorectal cancer diagnosis remains unclear.</p><p><b>Experimental Design:</b> We prospectively assessed the association of postdiagnostic calcium intake with colorectal cancer–specific and overall mortality among 1,660 nonmetastatic colorectal cancer patients within the Nurses' Health Study and the Health Professionals Follow-up Study. Patients completed a validated food frequency questionnaire between 6 months and 4 years after diagnosis and were followed up for death. Multivariable hazard ratios (HRs) and 95% confidence intervals (95% CI) were calculated using Cox proportional hazards regression.</p>Results:<p>Comparing the highest with the lowest quartile intake of postdiagnostic total calcium, the multivariable HRs were 0.56 (95% CI, 0.32–0.96; <i>P</i> <sub>trend</sub> = 0.04) for colorectal cancer–specific mortality and 0.80 (95% CI, 0.59–1.09; <i>P</i> <sub>trend</sub> = 0.11) for all-cause mortality. Postdiagnostic supplemental calcium intake was also inversely associated with colorectal cancer–specific mortality (HR, 0.67; 95% CI, 0.42–1.06; <i>P</i> <sub>trend</sub> = 0.047) and all-cause mortality (HR, 0.71; 95% CI, 0.54–0.94; <i>P</i> <sub>trend</sub> = 0.008), although these inverse associations were primarily observed in women. In addition, calcium from diet or dairy sources was associated with lower risk in men.</p>Conclusions:<p>Higher calcium intake after the diagnosis may be associated with a lower risk of death among patients with colorectal cancer. If confirmed, these findings may provide support for the nutritional recommendations of maintaining sufficient calcium intake among colorectal cancer survivors.</p></div>