One potential mechanism by which diet and lifestyle may affect chronic disease risk and subsequent mortality is through chronic systemic inflammation. In this study, we investigated whether the inflammatory potentials of diet and lifestyle, separately and combined, were associated with all-cause, all-CVD and all-cancer mortality risk. We analysed data on 18 484 (of whom 4103 died during follow-up) Black and White men and women aged ≥45 years from the prospective REasons for Geographic and Racial Differences in Stroke study. Using baseline (2003-2007) Block 98 FFQ and lifestyle questionnaire data, we constructed the previously validated inflammation biomarker panel-weighted, 19-component dietary inflammation score (DIS) and 4-component lifestyle inflammation score (LIS) to reflect the overall inflammatory potential of diet and lifestyle. From multivariable Cox proportional hazards models, the hazards ratios (HR) and their 95 % CI for the DIS-all-cause mortality and LIS-all-cause mortality risk associations were 1·32 (95 % CI (1·18, 1·47); Pfor trend < 0·01) and 1·25 (95 % CI (1·12, 1·38); Pfor trend < 0·01), respectively, among those in the highest relative to the lowest quintiles. The findings were similar by sex and race and for all-cancer mortality, but weaker for all-CVD mortality. The joint HR for all-cause mortality among those in the highest relative to the lowest quintiles of both the DIS and LIS was 1·91 (95 % CI 1·57, 2·33) (Pfor interaction < 0·01). Diet and lifestyle, via their contributions to systemic inflammation, separately, but perhaps especially jointly, may be associated with higher mortality risk among men and women.
Keywords: All-cause mortality; Cause-specific mortality; Diet; Inflammation; Lifestyle; Prospective studies.