NAFLD confers twofold risk increase for incident diabetes

Patients with non-alcoholic fatty liver disease are more likely to develop diabetes, according to a meta-analysis published in Gut.

Giovanni Targher, MD, of the University of Verona in Italy, and colleagues wrote that NAFLD and diabetes frequently co-exist and act together to increase risk for clinical outcomes.

“To date, however, it is becoming increasingly clear that the link between NAFLD and diabetes is more complex than previously believed,” they wrote. “Indeed, accumulating evidence suggests that the relationship between NAFLD and diabetes is mutual and bidirectional, and that NAFLD may also precede and/or promote the development of type 2 diabetes.”

Investigators searched the literature for observational studies that included NAFLD diagnosis by imaging or biopsy and had a follow-up of at least 1 year, and they used those data to explore the association between NAFLD and risk for incident diabetes.

Researchers identified 33 studies comprising 501,022 individuals and 27,953 cases of diabetes.

Patients with diabetes had a higher risk for incident diabetes than individuals without NAFLD (HR = 2.19; 95% CI, 1.93-2.48). Patients with more severe NAFLD were also more likely to develop diabetes (HR = 2.69; 95% CI, 2.08-3.49).

The risk increased with the severity of liver fibrosis (HR = 3.42; 95% CI, 2.29-5.11).

“This large and updated meta-analysis provides clear evidence for a significant positive association between the presence of imaging-defined or biopsy-proven NAFLD and the long-term risk of incident diabetes,” Targher and colleagues wrote. “The magnitude of this risk parallels the underlying severity of NAFLD.

“Mechanistic studies are also needed to better understand the link between NAFLD and diabetes risk.”