Lifestyle-related liver improvements may also help kidneys

Last Updated: 2016-12-05

By David Douglas

NEW YORK (Reuters Health) - Patients with non-alcoholic steatohepatitis (NASH) who benefit from a low-fat diet and more exercise also show an improvement in renal function, according to a post hoc analysis of a recent trial.

"Our data reveal a tight association between resolution of NASH and fibrosis regression mediated by lifestyle intervention and improvement in kidney function," Dr. Eduardo Vilar-Gomez of Virgen del Rocio University Hospital, Seville, Spain told Reuters Health by email.

As reported November 16 online in Alimentary Pharmacology and Therapeutics, Dr. Vilar-Gomez and colleagues examined data on 261 patients with NASH who were treated with lifestyle modifications over the course of a year. The mean age was about 48 years and most (61%) were women. A third of patients had type 2 diabetes mellitus and more than half were hypertensive.

At 52 weeks, estimated glomerular filtration rates (eGFR) were stable in 59%, improved in 25% and worsened in 16%. Patients with significant weight loss were more likely to show improved or stabilized eGFR.

Following the intervention, reduction in fibrosis and resolution of NASH were significantly correlated with an improvement in kidney function, the authors found. In patients with fibrosis improvement there was a significant renal improvement, compared to those in whom fibrosis had not improved.

This amounted to an eGFR increase of 7.6 mL/min/1.73 m2 versus a reduction of 1.98 mL/min/1.73 m2. There were similar findings in those with NASH improvement compared to those with no NASH improvement.

Other factors - including change in HbA1c, diastolic blood pressure, use of statins or diabetes at baseline - were unrelated to changes in renal function.

After controlling for confounders, the association between fibrosis improvement, NASH resolution and eGFR change remained significant.

Weight loss improved renal function irrespective of baseline glomerular filtration, the authors found.

They observe, "Improvement in liver histology due to lifestyle modification is independently associated with improved kidney function in NASH."

New drugs for NASH are emerging, but "the impact of improvement in NASH histology in subjects undergoing pharmacological therapies remains to be clarified," Dr. Vilar-Gomez said.

Commenting by email, Dr. Vlad Ratziu of Pierre and Marie Curie University, Paris, told Reuters Health that the "modest although significant improvement in creatinine clearance" parallels weight loss and histological improvement, and "it is difficult to tease out the independent contribution of histological improvement versus weight loss itself, changes in diet (or unrecorded changes in lifestyle) or simply improvement in arterial hypertension and other determinants of impaired renal function."

"While provocative," he concluded, "these data need confirmation and a more extensive analysis of the numerous confounders before any causal relationship between hepatic histologic improvement and improvement in renal function can be hypothesized. The short period of time (one year only) also questions the physiological plausibility of an independent and causal relationship."

SOURCE: http://bit.ly/2gbSiSA

Aliment Pharmacol Ther 2016.