Impact of liver fibrosis and clinical characteristics on dose-adjusted serum methadone concentrations
AuthorChalabianloo, Fatemeh; Høiseth, Gudrun; Vold, Jørn Henrik; Johansson, Kjell Arne; Kringen, Marianne K.; Dalgard, Olav; Ohldieck, Christian; Druckrey-Fiskaaen, Karl Trygve; Aas, Christer Frode; Løberg, Else-Marie; Bramness, Jørgen Gustav; Fadnes, Lars T.
Results: When adjusted for age, gender, body mass index, and genotypes of CYP2B6 and CYP3A5, the concentration-to-dose ratio of methadone did not increase among the participants with liver fibrosis (Coefficient: 0.70; 95% CI: −2.16, 3.57; P: 0.631), even among those with advanced cirrhosis (−0.50; −4.59, 3.59; 0.810).
Conclusions: Although no correlation was found between the degree of liver stiffness and dose-adjusted serum methadone concentration, close clinical monitoring should be considered, especially among patients with advanced cirrhosis. Still, serum methadone measurements can be considered a supplement to clinical assessments, taking into account intra-individual variations.