The association of uric acid with mortality modifies at old age: data from the uric acid right for heart health (URRAH) study.

OBJECTIVES: In older individuals, the role of serum uric acid (SUA) as risk factor for mortality is debated. This study investigated the association of SUA with all-cause and cardiovascular (CV) mortality in older adults participating in the large multicentre observational uric acid right for heart health (URRAH) study. METHODS: Eight thousand URRAH participants aged 65+ were included in the analysis. The predictive role of SUA was assessed using Cox regression models stratified according to the cut-off age of 75. SUA was tested as continuous and categorical variable (age-specific quartiles). The prognostic threshold of SUA for mortality was analysed using receiver operating characteristic curves. RESULTS: Among participants aged 65-74, multivariate Cox regression analysis adjusted for CV risk factors and comorbidities identified an independent association of SUA with both all-cause mortality (hazard ratio [HR] 1.169, 95% confidence interval [CI] 1.107-1.235) and CV mortality (HR 1.146, 95% CI 1.064-1.235). The cut-off value of 4.8 mg/dl discriminated mortality status. In participants aged 75+, we observed a J-shaped relationship of SUA with all-cause and CV mortality, with risk increasing at extreme SUA levels. CONCLUSIONS: These results confirmed the predictive role of SUA for all-cause and CV mortality in older adults, while revealing considerable age-related differences. Mortality risk increased at higher SUA levels in participants aged 65-74, with a prognostic threshold of 4.8 mg/dl. The relationship between SUA and mortality was J-shaped in oldest participants. Large interventional studies are needed to clarify the benefits and possible risks of urate-lowering treatments in older adults.

Serum uric acid and fatal myocardial infarction: detection of prognostic cut-off values: The URRAH (Uric Acid Right for Heart Health) study.

OBJECTIVE: The Working Group on Uric Acid and Cardiovascular Risk of the Italian Society of Hypertension conceived and designed an ad-hoc study aimed at searching for prognostic cut-off values of serum uric acid (SUA) in predicting fatal myocardial infaction (MI) in women and men. METHODS: The URic acid Right for heArt Health study is a nationwide, multicentre, observational cohort study involving data on individuals aged 18-95 years recruited on a regional community basis from all the territory of Italy under the patronage of the Italian Society of Hypertension with a mean follow-up period of 122.3 ±â€Š66.9 months. RESULTS: A total of 23 467 individuals were included in the analysis. Cut-off values of SUA able to discriminate MI status were identified by mean of receiver operating characteristic curves in the whole database (>5.70 mg/dl), in women (>5.26 mg/dl) and in men (>5.49 mg/dl). Multivariate Cox regression analyses adjusted for confounders (age, arterial hypertension, diabetes, chronic kidney disease, smoking habit, ethanol intake, BMI, haematocrit, LDL cholesterol and use of diuretics) identified an independent association between SUA and fatal MI in the whole database (hazard ratio 1.381, 95% confidence intervals, 1.096-1.758, P = 0.006) and in women (hazard ratio 1.514, confidence intervals 1.105-2.075, P < 0.01), but not in men. CONCLUSION: The results of the current study confirm that SUA is an independent risk factor for fatal MI after adjusting for potential confounding variables, and demonstrate that a prognostic cut-off value associated to fatal MI can be identified at least in women.