Increased arterial stiffness in nonalcoholic fatty liver disease: a systematic review and meta-analysis

Arterial function is a marker of early atherosclerotic changes and cardiovascular disease. Several studies have suggested the possible association between nonalcoholic fatty liver disease (NAFLD) and increased arterial stiffness. Thus, we conducted a systematic review and meta-analysis to better characterize this association.

A comprehensive search of the databases of the MEDLINE and EMBASE was carried out from inception through September 2016. All observational studies that compared arterial stiffness between NAFLD patients and healthy controls were included. Arterial stiffness was measured by pulse wave velocity (PWV) and augmentation index. We calculated pooled mean difference (MD) with 95% confidence intervals (CIs) using the random-effects model.

Data were extracted from 12 studies involving 9351 NAFLD patients and 17 684 controls. NAFLD is significantly associated with increased arterial stiffness as determined by carotid-femoral PWV (MD=0.75 m/s, 95% CI: 0.43-1.07, I=88%), brachial-ankle PWV (MD=0.82 m/s, 95% CI: 0.57-1.07, I=92%), and augmentation index (pooled MD=2.54%, 95% CI: 0.07-5.01, I=73%) compared with healthy controls.

In conclusion, our study demonstrated a higher degree of arterial stiffness in NAFLD patients compared with controls. However, this association might be related to the higher prevalence of cardiometabolic risk factors in NAFLD patients. Further studies are needed to determine an independent association between NAFLD and arterial stiffness adjusting to cardiometabolic risks.