Rheumatoid arthritis (RA) is an autoimmune disease characterised by chronic inflammation of the joints. Anaemia, a common complication in patients with RA, is associated with an increased risk of physical disability and early mortality.
This study aims to clarify the prevalence of anaemia in patients with RA and to explore its association with the Inflammatory Food Index (IFI), which measures the inflammatory potential of the diet.
The data for this study comes from the National Health and Nutrition Examination Survey (NHANES) covering the period from 1999 to 2018. Participants in the study were individuals who had self-reported a diagnosis of RA. After careful selection and exclusion of those with missing data, 2287 participants were included. Anemia was defined according to World Health Organization (WHO) diagnostic criteria. ADI levels were calculated from participants' 24-hour dietary recalls, based on 28 dietary components.
The prevalence of anaemia in RA patients in the United States has been estimated at 10.25%. The lowest prevalence of anaemia was observed around the age of 60. In addition, levels of IAA were significantly higher in anaemic patients compared to non-anaemic patients.
Multivariate regression analyses revealed a significant association between increased risk of anaemia and increasing levels of IAA.
The study used stepwise regression to identify the most crucial dietary factors associated with anaemia risk in RA patients.
The study provides strong evidence for the association between pro-inflammatory diets and increased risk of anaemia in RA patients. The consumption of anti-inflammatory foods could potentially reduce systemic inflammation and therefore reduce the risk of anaemia. However, factors such as socio-economic status and the use of anti-rheumatic drugs could also influence these results.
In conclusion, this study showed that the prevalence of anaemia in patients with RA is significantly associated with high levels of IAA. Management of dietary inflammation could play a crucial role in the prevention and treatment of anaemia in these patients. Further research, including prospective studies, is needed to confirm these results and explore the underlying mechanisms.
