A nutrigenetic precision approach for the management of non-alcoholic fatty liver disease

BACKGROUND & AIMS

The Patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 single nucleotide polymorphism (SNP) is one of the major genetic determinant of non-alcoholic fatty liver disease (NAFLD) and is strongly regulated by changes in energy balance and dietary factors. We aimed to investigate the association between the PNPLA3 rs738409 SNP, nutrient intake and NAFLD severity.

METHOD

PNPLA3-rs738409 SNP was genotyped in 181 patients with NAFLD who completed the EPIC Food Frequency Questionnaire. Liver steatosis was evaluated by Controlled Attenuation Parameter (CAP) (Fibroscan®530, Echosens). According to the established cut-off, a CAP value ≥ 300 dB/m was used to identify severe steatosis (S3). An independent group of 46 biopsy-proven NAFLD subjects was used as validation cohort.

RESULTS

Overall, median age was 53 years (range 44; 62) and 60.2% of patients were male. Most subjects (56.3%) had S3 and showed increased liver stiffness (p < 0.001), AST (p = 0.003) and ALT levels (p < 0.001) compared to those with CAP<300 dB/m. At logistic regression analyses we found that the interaction between carbohydrates intake and the carriers of the PNPLA3 G risk allele was significantly associated with S3 (p = 0.001). The same result was confirmed in the validation cohort, were the interaction between high carbohydrate intake (48%) and PNPLA3 SNP was significantly associated with steatosis ≥33% (p = 0.038).

CONCLUSION

The intake of greater than or equal to 48% carbohydrate in NAFLD patients carriers of the CG/GG allele of PNPLA3 rs738409 may increase the risk of significant steatosis.

Impact of Health Related QoL and Mediterranean Diet on Liver Fibrosis in Patients with NAFLD

Patients with non-alcoholic fatty liver disease (NAFLD) display impaired health-related quality of life (HRQoL) that is often linked to an unhealthy dietary pattern. The aim of this work was to investigate the impact of HRQoL and adherence to the Mediterranean diet on the risk of liver fibrosis (LF) in patients with NAFLD. LF was assessed in 244 patients through transient elastography (FibroScan^®530. Echosens, Paris, France). Significant LF was defined according to liver stiffness measurements (LSM) values ≥ 7.1 kPa. The Mediterranean diet score and the Short Form-36 questionnaires were also completed. The median age was 54 (44-62) years and 57% of participants were male. A total of 42 (17.2%) participants had LSM ≥ 7.1 kPa and showed increased GGT (p = 0.001), glucose (p < 0.001), and triglycerides levels (p = 0.015) compared to those with LSM ≤7.0 kPa. Moreover, patients with significant LF had significantly lower scores related to Physical Functioning (p < 0.001) and Role Physical (p < 0.001). In the logistic regression analysis, lower role physical and lower adherence to the MedDiet (p = 0.001 and p = 0.009, respectively), after adjusting for age, diabetes, and obstructive sleep apnea, were associated with an increased risk of significant LF. Low adherence to MedDiet and low role physical may influence the risk of significant liver fibrosis in patients with NAFLD.