Geriatric nutritional risk index and mortality risk in elderly patients with rheumatoid arthritis: evidence from NHANES (1999-2018).

BACKGROUND

Rheumatoid arthritis (RA) could increase all-cause and cardiovascular mortality, particularly in elderly patients. Malnutrition is usually found in RA and contributes to poorer outcomes, with geriatric nutritional risk index (GNRI) serving as a dependable indicator to provide information on nutritional risk in elderly populations. We aim to elucidate connection between GNRI and survival outcomes in elderly RA patients.

METHODS

Using NHANES database from 1999-2018, 1,473 RA patients ≥ 60 years old have been chosen. Participants were categorized into High-GNRI and Low-GNRI group with a threshold of 98. Mortal status was extracted from the Linked Mortality Files. Cox regression was utilized to further assess the relationship.

RESULTS

Higher GNRI was significantly associated with lower all-cause (HR 0.563, 95% CI 0.423-0.751, p < 0.001) and cardiovascular mortality (HR 0.571, 95% CI 0.345-0.946, p = 0.030) in fully adjusted models, which was confirmed by Kaplan-Meier survival curves. Subgroup analyses further validated these associations across various demographic and clinical groups.

CONCLUSION

Higher GNRI is independently associated with a lower risk of all-cause and cardiovascular mortality in elderly RA patients, underscoring the importance of nutritional status in the survival of this population. Key Points • Higher GNRI was significantly associated with lower all-cause and cardiovascular mortality in elderly patients with rheumatoid arthritis. • Restricted cubic spline analysis revealed a linear association, with mortality risk decreasing as GNRI increased.