Current NAFLD guidelines for risk stratification in diabetic patients have poor diagnostic discrimination

Abstract

Patients with type 2 diabetes (T2D) are at risk for non-alcoholic fatty liver disease (NAFLD) and associated complications. This study evaluated the performance of international (EASL-EASD-EASO) and national (DGVS) guidelines for NAFLD risk stratification. Patients with T2D prospectively underwent ultrasound, liver stiffness measurement (LSM) and serum-based fibrosis markers. Guideline-based risk classification and referral rates for different screening approaches were compared and the diagnostic properties of simplified algorithms, genetic markers and a new NASH surrogate (FAST score) were evaluated. NAFLD risk was present in 184 of 204 screened patients (age 64.2 ± 10.7 years; BMI 32.6 ± 7.6 kg/m²). EASL-EASD-EASO recommended specialist referral for 60-77% depending on the fibrosis score used, only 6% were classified as low risk. The DGVS algorithm required LSM for 76%; 25% were referred for specialised care. The sensitivities of the diagnostic pathways were 47-96%. A simplified referral strategy revealed a sensitivity/specificity of 46/88% for fibrosis risk. Application of the FAST score reduced the referral rate to 35%. This study (a) underlines the high prevalence of fibrosis risk in T2D, (b) demonstrates very high referral rates for in-depth hepatological work-up, and (c) indicates that simpler referral algorithms may produce comparably good results and could facilitate NAFLD screening.

Figure 1

Diagnostic algorithms of guideline recommendations for screening and risk stratification in NAFLD patients^,. NFS NAFLD Fibrosis score, FIB-4 Fibrosis-4, LSM liver stiffness measurement.

Figure 2

Consort diagram. NAFLD Non-alcoholic fatty liver disease.

Figure 3

A/B: Guideline recommendations: clinical consequences and referral rates of diagnostic algorithms proposed by current guidelines in 184 patients with type 2 diabetes and NAFLD. DGVS DGVS S2k Guideline non-alcoholic fatty liver disease, EASL-EASD-EASO EASL–EASD–EASO Clinical practice guidelines for the management of NAFLD, LSM Liver stiffness measurement, FIB4 Fibrosis-4; age-adapted cut-offs for NAFLD fibrosis score and FIB4 score were used.

Figure 4

Risk stratification using non-invasive fibrosis scores with established aged-adapted cut-offs (sensitive/specific). The risk categories are colour-coordinated. Each patient’s result is imaged in grey horizontal lines. The more specific cut-off for FIB4 score (3.25) is additionally illustrated; FIB4 Fibrosis-4, LSM liver stiffness measurement, VCTE vibration controlled attenuation parameter.

Figure 5

Box plots of FAST score according to EASL-EASD-EASO recommendations. The dashed lines refer to the cut-offs suggested for the FAST score. For risk stratification the specific cut-off of 2.67 were used for FIB4 score.