The Serum γ-Glutamyltransferase Level Is Associated with the Development of Hypertension in Alcohol Infrequent Drinkers but Not in Frequent Drinkers

Objective The controversy persists regarding whether the serum level of γ-glutamyltransferase (GGT), a marker of liver damage, is associated with hypertension irrespective of alcohol intake. Methods We investigated the relationship between the GGT level and new-onset hypertension during a 10-year follow-up period in Japanese individuals who underwent annual health examinations (n=28,990). After excluding subjects without systolic blood pressure and GGT data and those with hypertension at baseline, a total of 18,618 subjects (men/women: 11,262/7,356, mean age: 44 years) were enrolled. Results During the follow-up period, 2,753 men (24.4%) and 837 women (11.4%) developed hypertension. When the subjects were divided by quartiles of GGT at baseline (Q1-Q4), multivariable Cox proportional hazard model analyses after adjustment for age, sex, systolic blood pressure, body mass index, levels of uric acid, estimated glomerular filtration rate, family history of hypertension, habits of current smoking and alcohol drinking, and diagnosis of diabetes mellitus and dyslipidemia showed that hazard ratios (HRs) for the development of hypertension were significantly higher in the Q2, Q3, and Q4 groups than in the Q1 group. A significant interaction was observed between alcohol drinking habits and the GGT level at baseline for the development of hypertension (p=0.022), and adjusted HRs were similarly significant in alcohol infrequent drinkers (≤5 days/week). However, the GGT level was not significantly associated with the development of hypertension in frequent alcohol drinkers (≥6 days/week). Conclusion A high GGT level is an independent predictor of new-onset hypertension in infrequent alcohol drinkers but not in frequent drinkers.