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

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.