Nutritional status as the risk factor of serious infection in patients with rheumatoid arthritis

Objectives: The aim of this study was to identify the risk factors associated with severe infection in RA patients, with a particular focus on the association of the nutritional status.Methods: We retrospectively analyzed data from 74 patients with RA (male, n = 21; female, n = 53; age 74.2 ± 12.4) admitted to our hospital between 2016 and 2017 for infection (infection group). We also recruited control RA patients (n = 222) who were matched for age, gender and disease duration, with a match ratio of 1:3 (non-infection group). The nutritional condition was assessed based on controlling nutrition status (CONUT) score, and prognostic nutritional index (PNI). The data of the infection group were obtained from the most recent visit prior to the present admission, and non-infection group from the last regular visit in 2017.Results: The respiratory tract was the most frequent site of infection. The BMI and PNI were significantly lower and the CONUT score significantly higher in the infection group than in the non-infection group. A logistic regression analysis revealed that the CONUT score, underlying lung disease and use of prednisolone and biological disease-modifying anti-rheumatic drugs were independent and significant risk factors for serious infection.Conclusion: Poor nutritional status increases the risk of serious infection.