1259Adherence to healthy diet reduces mortality associated with systemic inflammation

Background Systemic inflammation is a precursor of many chronic diseases that contributes to morbidity and mortality. In this study, we examined the joint association of systemic inflammation and diet quality with all-cause mortality. Methods A total of 27,305 adults (mean age = 50 years, male: 50.6%) from the National Health and Nutrition Examination Survey (1999-2010 and 2015-2018) were included in the study. A serum inflammatory marker, C-reactive protein (CRP), was measured. The Healthy Eating Index-2015 (HEI-15) was computed. Multivariable logistic regression analysis was used to determine the cross-sectional association between HEI-15 and inflammation. Multivariable Cox proportional hazard models were performed to assess the risk of all-cause mortality associated with the joint classification of inflammation and diet quality. Results In the cross-sectional study, a higher tertile of HEI-15 was associated with reduced odds of inflammation (OR = 0.85, 95% CI: 0.78-0.93) in all participants. Similar results were observed in obese and non-obese groups. In the prospective study (median follow-up = 9.4 years), a higher adherence to HEI-15 was associated with a reduced risk of mortality. Compared to non-obese group, obese participants with high levels of inflammation had a higher risk of all-cause mortality (HR = 1.26, 95% CI: 1.08-1.47; HR = 1.60, 95% CI: 1.19-2.17, respectively). Conclusions A higher adherence to HEI-15 was associated with reduced inflammation. Higher diet quality may reduce mortality risks associated with inflammation, particularly in non-obese groups and obese participants with moderate inflammation. Key messages Adhering to a high quality diet may mitigate the mortality risk associated with increased inflammation.