No association of NAFLD-related polymorphisms in PNPLA3 and TM6SF2 with all-cause and cardiovascular mortality in an Austrian population study

Abstract

Background and aims: Single-nucleotide-polymorphisms in PNPLA3-rs738409 and the TM6SF2-rs58542926, associated with metabolic-dysfunction-associated fatty liver disease (MAFLD), have been discussed as potentially protective for cardiovascular diseases. Therefore, we aimed to study the associations of PNPLA3/TM6SF2 variants with MAFLD and cardiovascular risk in a population-based sample of asymptomatic patients.

Methods: The study cohort comprised 1742 patients of European decent aged 45-80 years from a registry study undergoing screening colonoscopy for colorectal cancer between 2010 and 2014. SCORE2 and Framingham risk score calculated to assess cardiovascular risk. Data on survival were obtained from the national death registry RESULTS: Half of included patients were male (52%, 59 ± 10 years), 819 (47%) carried PNPLA3‑G and 278 (16%) TM6SF2-T-alleles. MAFLD (PNPLA3‑G-allele: 46% vs. 41%, p = 0.041; TM6SF2‑T-allele: 54% vs. 42%, p < 0.001) was more frequent in patients harbouring risk alleles with both showing independent associations with MAFLD on multivariable binary logistic regression analysis. While median Framingham risk score was lower in PNPLA3‑G-allele carriers (10 vs. 8, p = 0.011), SCORE2 and established cardiovascular diseases were similar across carriers vs. non-carriers of the respective risk-alleles. During a median follow-up of 9.1 years, neither PNPLA3‑G-allele nor TM6SF2‑T-allele was associated with overall nor with cardiovascular mortality.

Conclusion: Carriage of PNPLA3/TM6SF2 risk alleles could not be identified as significant factor for all-cause or cardiovascular mortality in asymptomatic middle-aged individuals undergoing screening colonoscopy.

Keywords: Cardiovascular risk; MAFLD; PNPLA3; TM6SF2.