Positive association between blood pressure (BP) and uric acid is evident, but specific effect size of serum uric acid (SUA) at different levels on BP is unclear, and interaction effect of SUA with other metabolic factors on BP was rarely reported. A cross-sectional study was conducted by making use of data from an epidemic investigation. A total of 3658 subjects were enrolled in our data analysis. In male subjects, for each 1 mg/dL increase in the SUA level, systolic blood pressure (SBP) and diastolic blood pressure (DBP) increased by 1.339 mmHg [95% CI: 0.552-2.126] and 0.515 mmHg [95% CI: 0.013-1.016], respectively, after adjusting for age, fasting plasma glucose (FPG), triglyceride (TG), total cholesterol (TC), estimated-glomerular filtration rate (eGFR), body mass index (BMI), drinking, smoking, and waist-hip ratio (WHR). And in female subjects, for each 1 mg/dL increase in the SUA level, SBP and DBP increased by 1.180 mmHg [95% CI: 0.401-1.959] and 0.549 mmHg [95% CI: 0.086-1.011], respectively, after adjusting the same factors. In males, in subjects with SUA < 6 mg/dL, SBP increased by 0.585 mmHg [95% CI: -0.976 to 2.146] for each 1 mg/dL increase in the SUA level, while in subjects with SUA ≥ 6 mg/dL, SBP increased by 3.271 mmHg [95% CI: 1.244-5.297] (p interaction = 0.0369), after adjusting age, BMI, smoking, drinking, TG, TC, FPG, eGFR, and WHR. This difference was not observed in DBP and females. Interaction effects between SUA and BMI, TG, FPG on BP were discovered. In conclusion, higher level of SUA has a stronger effect on BP and other metabolic factors: FPG, TG, and BMI could strengthen the effect of SUA on BP.
Keywords: Blood pressure; interaction effect; metabolic factor; serum uric acid.