Factors associated with hyperhomocysteinaemia in Mexican patients with rheumatoid arthritis

Background: Hyperhomocysteinaemia is a factor related to the development of atherosclerosis in rheumatoid arthritis (RA). However, Hispanics with RA develop high rates of coronary disease; there are no studies about the frequency and factors related to high levels of homocysteine in Mexican patients. Objective: To evaluate the prevalence and characteristics associated with hyperhomocysteinaemia in Mexican patients with RA. Methods: One hundred and fifty-two patients with RA were compared with 153 controls. The assessment in RA included clinical characteristics, disease activity (RADAR), functioning (HAQ-Di and global functional status), comorbidity, and radiological damage. Laboratory determinations included total serum homocysteine (tHcy), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), and lipid profile. Results: Median levels of homocysteine were higher in RA compared with controls (11.3 vs. 9.3, p < 0.001). Twenty per cent of the patients with RA had hyperhomocysteinaemia (> 15 μmol/L) compared with 6% in controls (p < 0.001). There was statistical association between hyperhomocysteinaemia in RA with male gender (p < 0.001), impairment in the global functional status (p=0.004), higher radiological damage (p=0.001), and CRP (p=0.04). There was no association with RADAR, HAQ-Di, or RF, methotrexate dose or duration of use. In the adjusted multivariate model, the two variables associated with higher risk for hyperhomocysteinaemia were male gender (OR=4.2, 95% CI 2 to 12, p=0.006) and higher radiological damage (III-IV) (OR=3.4, 95% CI 1.3 to 9, p=0.01). Conclusions: Our data show a high prevalence of hyperhomocysteinaemia in Mexican patients with RA. More effort is required to evaluate and treat earlier this coronary risk factor.