Greater Adherence to Lifestyle Recommendations after Cancer Diagnosis Is Associated with Lower Mortality in the UK Biobank

BACKGROUND: Research supporting the current recommendation to adhere to a healthy lifestyle following cancer diagnosis is limited. We investigated whether a healthy lifestyle after diagnosis is associated with a lower risk of mortality among those diagnosed with any malignant cancer and breast, colorectal, and prostate cancers. METHODS: In 2006 to 2010, UK Biobank participants (ages 37-73 years) were assessed. Analyses were restricted to those with a malignant cancer diagnosis prior to baseline (n = 20,805, including 5,845 breast, 1,943 colorectal, and 2,715 prostate cancer cases). Participants were followed for all-cause and cancer-specific death up to November 2022. A lifestyle index was determined based on lifestyle recommendations for cancer prevention. Cox regression was used to examine associations with all-cause and cancer-specific mortality among those with any cancer, and separately for breast, colorectal, and prostate cancers, adjusting for relevant confounders. RESULTS: There were 4,328 deaths and 3,354 cancer-specific deaths in the 258,985 person-years of follow-up. A higher lifestyle index, representing greater adherence to recommendations, was associated with a lower risk of all-cause mortality [any cancer - highest vs. lowest lifestyle index tertile: HR (95% confidence interval) = 0.77 (0.71, 0.83); breast: 0.75 (0.64, 0.88); colorectal: 0.68 (0.52, 0.89); and prostate: 0.73 (0.59, 0.89)] and cancer-specific mortality in all populations examined [any cancer: 0.82 (0.75, 0.89); breast: 0.88 (0.71, 1.09); colorectal: 0.58 (0.36, 0.94); prostate: 0.70 (0.53, 0.93)], although evidence was weaker for cancer-specific mortality among colorectal and breast cancer survivors. CONCLUSIONS: Our findings provide evidence to support the recommendation to follow a healthy lifestyle after cancer diagnosis to prolong life. IMPACT: Clinical guidelines and public health programs promoting a healthy lifestyle to cancer survivors may prolong life.