The dose-response relationship and gender differences of serum uric acid with total cholesterol: a cross-sectional study

Abstract

Objective: To explore the dose-response relationship and gender differences between serum uric acid (SUA) and total cholesterol (TC) in Chinese individuals.

Methods: This cross-sectional study included secondary data of Chinese adults, collected between 2010 and 2018. The exposure variable was SUA, the outcome variable was TC, and participants were split into five quantiles by SUA levels (Q1 [men, ≤283; women, ≤223] to Q5 [men, ≥416; women, ≥332]). Covariates included age, gender, laboratory and examination information. Multivariable linear regression and subgroup analysis were performed to examine the independent association between SUA and TC. Smooth curve fitting and threshold effect analysis was employed to assess potential non-linear relationships. Additionally, a sensitivity analysis was conducted to validate the robustness of the findings.

Results: The analysis included 6119 participants, of whom, 4078 (66.6%) were female, with a mean age of 63.7 years. After adjusting for potential confounders, SUA showed a significant association with TC in both men (β = 0.09; 95% confidence interval [CI] 0.05, 0.14) and women (β = 0.13; 95% CI 0.10, 0.17). The Q5 group exhibited higher TC levels than the Q1 group in both men (β = 0.26; 95% CI 0.16, 0.37) and women (β = 0.25, 95% CI 0.17, 0.32). In women, there was an inverted L-shaped relationship between SUA and TC with an inflection point at 359.962 μmol/L, whereas a linear relationship was exhibited in men. Subgroup analysis showed no significant interactions in men. Sensitivity analyses confirmed the robustness of the findings.

Conclusions: Significant sex differences and dose-response relationships exist between SUA and TC in the Chinese population. The study may provide new insights into cholesterol management.

Keywords: Serum uric acid; cross-sectional study; dose-response relationship; sex differences; total cholesterol.

Figure 1.

Results of multivariate smoothing splines analysis, showing: (a) linear relationship between SUA and TC in male participants; and (b) nonlinear relationship between SUA and TC in female participants. Adjustment factors included age, body mass index, systolic blood pressure, diastolic blood pressure, fasting blood glucose, creatinine and estimated glomerular filtration rate, respectively. Only 99% of the data are shown. The red line and pink area represent estimated values and corresponding 95% confidence intervals, respectively. SUA, serum uric acid; TC, total cholesterol.

Figure 2.

Subgroup analysis of relationships between SUA and TC in female participants grouped into 5 quantiles according to increasing SUA level (Q1–Q5). Coefficient (β) adjusted for age, BMI, systolic blood pressure, diastolic blood pressure, fasting blood glucose, creatinine and estimated glomerular filtration rate, respectively. BMI, body mass index; CI, confidence interval; SUA, serum uric acid (µmol/L); TC, total cholesterol.

Figure 3.

Subgroup analysis of relationships between SUA and TC in male participants grouped into 5 quantiles according to increasing SUA level (Q1–Q5). Coefficient (β) adjusted for age, BMI, systolic blood pressure, diastolic blood pressure, fasting blood glucose, creatinine and estimated glomerular filtration rate, respectively. BMI, body mass index; CI, confidence interval; SUA, serum uric acid (µmol/L); TC, total cholesterol.