Usefulness of uric acid to predict changes in C-reactive protein and interleukin-6 in 3-year period in Italians aged 21 to 98 years

The role of uric acid (UA) in the process of atherothrombosis is controversial. Although serum UA has powerful antioxidant properties, epidemiological studies showed that UA was a risk factor for cardiovascular diseases and was positively associated with proinflammatory markers. Relations between baseline UA and changes in UA circulating levels with C-reactive protein (CRP) and interleukin-6 (IL-6) after 3 years of follow-up in a cohort of 892 Italian men and women aged 21 to 98 years was investigated. Subjects had complete baseline and follow-up data for UA, inflammatory markers, and covariates. An autoregressive approach was used to study such a relation. In adjusted analyses, baseline UA and changes in UA predicted a 3-year change in CRP (p = 0.028), but not IL-6 (p = 0.101). The relation between UA and CRP persisted after adjustment for baseline IL-6. Subjects with high UA at baseline had a progressively higher probability of developing clinically relevant increased IL-6 (>2.5 pg/ml) and CRP (>3 mg/L) during 3 years. In conclusion, our study suggests that in a population-based cohort, baseline UA and changes in circulating UA during 3 years of follow-up predict changes in circulating CRP independent of relevant confounders, including baseline IL-6.