Development of new fatty liver, or resolution of existing fatty liver, over five years of follow-up, and risk of incident hypertension

Abstract

Background & aims: Approximately 50% of hypertensive patients have non-alcoholic fatty liver disease (NAFLD), but whether change in fatty liver status over time modifies risk of developing hypertension is uncertain. Our aim was to determine whether a change in fatty liver status (either development of new fatty liver, or resolution of existing fatty liver) over five years modified risk of incident hypertension at five year follow-up.

Methods: 11,448 patients without hypertension were examined at baseline and at five year follow-up, using a retrospective cohort study design. Fatty liver status (absent or present) was assessed at baseline and follow-up using standard ultrasound criteria. Adjusted odds ratios (aOR) and 95% confidence intervals (CIs) for incident hypertension at follow-up were estimated controlling for potential confounders, compared to the reference group (patients who did not have fatty liver at either baseline or follow-up).

Results: 911 patients developed incident hypertension. Incident fatty liver developed during follow-up in 1418 patients and fatty liver at baseline resolved during follow-up in 684 patients. Developing incident fatty liver was associated with incident hypertension, even after adjustment for multiple confounders (aOR=1.60 (95% CI 1.30, 1.96; p<0.001). Further adjustment for change in body mass index between baseline and follow-up only slightly attenuated this association (aOR=1.36 (95% CI 1.10, 1.67; p=0.004). With resolution of fatty liver at follow-up, risk of incident hypertension was not different from the reference group (aOR=1.21 (95% CI 0.90, 1.63; p=0.21).

Conclusions: Development of incident fatty liver is associated with increased risk of hypertension.

Keywords: Hypertension; Insulin resistance; Metabolic syndrome; Non-alcoholic fatty liver disease; Obesity; Type 2 diabetes.