Prognostic nutritional index as an indicator for the development of bone fragility fracture in patients with rheumatoid arthritis

Abstract

ABSTRACT Objectives The validity of prognostic nutritional index (PNI) as an index of incident bone fragility fracture (inc-BFF) in rheumatoid arthritis (RA) patients was investigated. Methods RA patients whom continuously followed up for >3 years were picked up. Patients were classified in accordance with inc-BFF positivity (BFF+ and BFF−). Their clinical background including PNI was statistically examined for inc-BFF. The background factors were compared between the two groups. Patients were narrowed into subgroups according to the factor that showed a significant difference between the two groups, and they were statistically examined according to the PNI for the inc-BFF. The two groups were narrowed with propensity score matching and compared to the PNI. Results A total of 278 patients with 44 BFF+ and 234 BFF− were recruited. In the background factors, the presence of prevalent BFF and the simplified disease activity index remission rate had a significantly higher risk ratio. In a subgroup who comorbid lifestyle-related diseases, PNI had a significantly higher risk ratio for the inc-BFF. After the propensity score matching, the PNI showed no significant difference between the two groups. Conclusions PNI is available when patients with RA comorbid lifestyle-related diseases. PNI is not an independent key for the inc-BFF in RA patients.