The influence of coffee intake and genetics on adenosine pathway in rheumatoid arthritis.

Aim: We studied the influence of coffee consumption on the therapeutic effect of methotrexate (MTX) in patients with rheumatoid arthritis (RA) sorted according to ADORA2A genotypes. Patients & methods: 82 RA patients were dichotomized according to caffeine intake with a threshold of 700 mg/week. Disease activity score 28 (DAS28) was applied (>3.2 - high; <3.2 - low or remission). Patients were genotyped using quantitative PCR allelic discrimination. Results: We found significantly higher risk of RA in patients with higher caffeine intake and the CT genotype of ADOARA2A rs2298383, rs3761422 and rs2267076 SNPs. The CC genotype of ADORA2A rs2236624 SNP in patients with lower caffeine intake treated with MTX is significantly protective. Conclusion:ADORA2A genotypes and coffee intake influence risk of RA and efficacy of it MTX treatment.