The effects of cardiometabolic factors on the association between serum uric acid and risk of all-cause mortality in adults with congestive heart failure

ABSTRACT Background Serum uric acid (SUA) has been shown to increase all-cause mortality from cardiovascular disease. However, limited studies have examined the mediating effect of dyslipidemia, hyperglycemia, or hypertension on the association between SUA and all-cause mortality in patients with congestive heart failure (CHF). Methods Participants in the present investigation were 620 US adults with CHF from the NHANES database (1999–2014). The relationship between SUA and all-cause mortality was evaluated utilizing multivariable Cox proportional hazards models. Additionally, the nonlinearity between SUA and mortality was investigated utilizing Restricted Cubic Splines (RCS) and 2-piecewise Cox proportional hazards models. Finally, the mediating role of cardiometabolic factors on the relationship between SUA and all-cause mortality was investigated utilizing the mediation analysis. Results During a mean follow-up of 7.6 years, 391 (63.1%) all-cause deaths occurred. Furthermore, we found a U-shaped association between SUA and all-cause mortality. The inflection point for the RCS curve was found at a SUA level of 363 umol/L. The hazard ratios (95% confidence intervals) for all-cause mortality were 0.998 (0.995–1.000) and 1.003 (1.002–1.005) to the left and right of the inflection point, respectively. This U-shaped association was also observed in both subgroups of sex and age. Moreover, the effect of SUA on all-cause mortality was not mediated by hypertension, hyperglycemia, or dyslipidemia (all P-values>0.05). Conclusion The association between SUA level and all-cause mortality followed a U-shaped curve, and this association was not mediated by hypertension, hyperglycemia, or dyslipidemia.