Higher serum alanine aminotransferase levels and the incidence of hypertension: the Kailuan cohort study

Objective The association between serum alanine aminotransferase (ALT) concentrations and the incidence of hypertension remains unclear. To explore the association between serum ALT levels and the risk of incident hypertension based on the Kailuan cohort study. Methods People who had participated in health check-ups in 2006-2007 without hypertension, cardiovascular, or liver diseases were enrolled and received follow-ups every two years until December 2017. Hypertension was defined as systolic blood pressure/diastolic blood pressure ≥140/90 mmHg or using anti-hypertensive medication. A multivariable-adjusted Cox regression model was used to estimate the hazard ratio (HR) and its corresponding 95% confidence intervals (95% CIs). Results During 10.5 years of follow-up, 24,023 (50.7%) participants were diagnosed with hypertension. The HR of incident hypertension was 1.02 (95% CI=1.01–1.03) for each 10 U/L increment of ALT concentrations. Participants with elevated ALT levels (>40 U/L) had an increased incidence of hypertension by 7% (HR =1.07; 95% CI=1.01–1.13). Besides, the HR was 1.10 (95% CI=1.06–1.15), 1.13 (95% CI=1.08–1.18), and 1.22 (95% CI=1.16–1.30) (P for trend <0.001) in (10-20], (20–30], and (30–40] groups, compared with ≤10 U/L group. In addition, participants whose ALT levels decreased to the normal range at the first follow-up had a 23% lower incidence of hypertension than those with elevated ALT levels at baseline and the first follow-up. Conclusion People with higher serum ALT levels may have an increased risk of incident hypertension and thus may benefit from heightened surveillance for hypertension and lifestyle interventions to reduce the risk of hypertension.