Patients with rheumatoid arthritis (RA) have significantly increased cardiovascular (CV) morbidity and mortality that are not accounted for by traditional risk factors alone. Paraoxonase 1 (PON1) and 25-hydroxyvitamin D have been shown to be involved in the pathogenesis of CV diseases. Objective: This study aimed to investigate PON1 gene polymorphism and serum 25-hydroxyvitamin D concentrations in RA patients, and to determine their association with CV risk in RA.
Serum samples from 46 RA patients and 45 healthy controls were tested for PON1 R192Q genotypes and serum vitamin D concentrations. The cardiovascular risks were assessed by Q-risk. Lipoprotein cholesterol levels, traditional CV risk factors, medication use, and RA disease activity status were also assessed.
PON1 polymorphism and low serum 25-hydroxyvitamin D were significantly associated with increased CV risk (p < 0.05). Compared to patients with either the PON1 QQ genotype or the QR genotype, patients with the RR genotype demonstrated decreased CV risk on multivariate analysis, controlling for traditional CV risk factors, C-reactive protein levels, prednisone use, and cholesterol-lowering medication use (p < 0.05).
There was a relationship of the genetic determinants of paraoxonase 1 (PON1 192) and serum 25-hydroxyvitamin D to CV risk in RA patients. Paired measurement of paraoxonase 1 genotype and serum 25-hydroxyvitamin D can be used as biomarkers of CV risk in RA patients.