Gamma-Glutamyltransferase Levels and Hypertension Risk: A U-Shaped Relationship in a Large Chinese Health Checkup Population .

OBJECTIVE: The association of Gamma-glutamyltransferase (GGT) with hypertension remains unclear due to previous studies. This study aims to investigate the relationship between GGT and hypertension in a large health checkup population from Wuhu, China. METHODS: A cross-sectional study was conducted at the First Affiliated Hospital of Wannan Medical College from 2011 to 2016. A total of 303,431 individuals who underwent physical examination and biochemical testing were enrolled in this study. Multivariable logistic regression model and restricted cubic spline models were employed to examine the relationship between GGT levels and hypertension. RESULTS: Compared to individuals with normal blood pressure, GGT levels were higher in the hypertensive group (23.15 [14.00-34.98] vs. 37.00 [21.00-51.00] U/L, p < 0.001), and the prevalence of elevated GGT was also higher (9.59% vs. 25.12%, p < 0.001). After adjusting for age, sex, smoking, drinking, BMI, triglycerides, total cholesterol, total protein, and albumin (Model 4), GGT quartiles were significantly associated with hypertension (p < 0.001). Compared with Q1, the odds ratios (ORs) for hypertension were 0.958 (95% CI: 0.926-0.991), 0.717 (95% CI: 0.691-0.743), and 2.421 (95% CI: 2.340-2.504), respectively. The restricted cubic spline model demonstrated a nonlinear association between GGT and hypertension (p < 0.001). The odds ratio (OR) for hypertension initially decreased and then increased as GGT levels rose. When GGT levels ranged from 15.03 U/L to 24.61 U/L, the OR for hypertension was less than 1.0. Similar trends were observed after grouping by gender. CONCLUSIONS: This study found a positive association between GGT and hypertension at both low and high GGT levels, while a negative association was observed at moderate GGT levels.