Association of inflammation and nutrition-based indicators with chronic obstructive pulmonary disease and mortality

Inflammation and nutrition are strongly linked to respiratory diseases, but the link between inflammation and nutrition-based indicators and chronic obstructive pulmonary disease (COPD) and its mortality has not been reported.

We recruited adults no younger than 20 years old from the NHANES 1999-2018. Inflammation and nutrition-based indicators included NAR, PNI, MAR, RAR, HALP, and ALI. COPD were assessed through a self-report questionnaire. Participants' mortality rates were determined by association with the National Death Index.

A total of 46,572 individuals were collected in this study, including 1,549 COPD patients. NAR, MAR, and RAR were positively linked with the prevalence of COPD. However, PNI and HALP were negatively linked with the prevalence of COPD. In participants with COPD, the highest quartile of NAR (HR = 1.43 [1.04-1.97]), MAR (HR = 1.66 [1.23-2.26]), and RAR (HR = 2.45 [1.90-3.17]) were linked with an increased risk of all-cause mortality compared to the lowest quartile. However, the highest quartile of PNI (HR = 0.48 [0.38-0.61]) and HALP (HR = 0.56 [0.44-0.71]) were linked with a decreased risk of all-cause mortality compared to the lowest quartile. Randomized survival forests (RSF) showed that RAR had the strongest predictive power for all-cause mortality in COPD individuals among all indicators.

We found that inflammation and nutrition-based indicators were linked to prognosis in COPD patients, with RAR having the highest predictive value.