Higher skin autofluorescence in individuals at risk for rheumatoid arthritis: results from a large population based cohort

OBJECTIVES: To investigate skin autofluorescence (SAF) levels, an early indicator for cardiovascular disease, in relation to the presence of anticitrullinated protein antibodies (ACPA), joint complaints and rheumatoid arthritis (RA) in a large population-based cohort.

METHODS: Cross-sectional data were used from 17346 participants of the Dutch Lifelines Cohort Study, of whom baseline SAF and ACPA levels were available. Individuals were divided into four groups: ACPA-negative controls (n=17211), ACPA-positive without joint complaints (n=49), ACPA-positive RA risk (n=31) and defined RA (n=52). Multinomial regression was used to compare SAF levels and correct for potential confounders.

RESULTS: SAF levels were higher in the ACPA-positive RA risk group (OR 2.04, p=0.034) and the defined RA group (OR 3.10, p<0.001) compared to controls, but not in the ACPA-positive without joint complaints group (OR 1.07, p=0.875). The difference in SAF levels remained statistically significant in the defined RA group after adjusting for age (OR 2.09, p=0.011), smoking status, renal function or HbA1c. In the ACPA-positive RA risk group, the effect was found to be comparable (corrected for age: OR 2.09).

CONCLUSIONS: Our results indicate that ACPA-positive individuals with RA risk have elevated SAF levels, which is regarded as a non-invasive marker for oxidative stress and a possible indicator for development of cardiovascular disease. Therefore, it is important to conduct further studies to explore if, in ACPA-positive individuals with RA risk and no diagnosis of RA, cardiovascular risk management should be considered in future clinical practice.