• Detection of Nonadherence to Antihypertensive Treatment by Measurements of Serum Drug Concentrations 

      Bergland, Ola Undrum; Halvorsen, Lene Vernås; Søraas, Camilla Lund; Hjørnholm, Ulla; Kjær, Vibeke Norheim; Rognstad, Stine; Brobak, Karl Marius; Aune, Arleen; Olsen, Eirik; Fauchald, Ylva; Heimark, Sondre; Thorstensen, Christian W; Liestøl, Knut; Solbu, Marit Dahl; Gerdts, Eva; Mo, Rune; Rostrup, Morten; Kjeldsen, Sverre; Høieggen, Aud; Opdal, Mimi Stokke; Fadl Elmula, Fadl Elmula M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-19)
      Nonadherence to drugs is a challenge in hypertension treatment. We aimed to assess the prevalence of nonadherence by serum drug concentrations compared with 2 indirect methods and relate to the prescribed drug regimens in a nationwide multicenter study. Five hundred fifty patients with hypertension using ≥2 antihypertensive agents participated. We measured concentrations of 23 antihypertensive drugs ...
    • Development of UHPLC-MS/MS methods to quantify 25 antihypertensive drugs in serum in a cohort of patients treated for hypertension 

      Thorstensen, Christian W.; Clasen, Per-Erik; Rognstad, Stine; Haldsrud, Renate; Føreid, Siri; Helstrøm, Trine; Bergland, Ola Undrum; Halvorsen, Lene Vernås; Aune, Arleen; Olsen, Erik; Brobak, Karl Marius; Høieggen, Aud; Gustavsen, Ingebjørg G.; Larstorp, Anne Cecilie Kjeldsen; Søraas, Camilla Lund; Opdal, Mimi Stokke (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-23)
      We developed three ultra-high pressure liquid chromatography coupled to mass spectrometry detection (UHPLCMS/MS) methods to quantify 25 antihypertensive drugs in serum samples. Patient-reported drug lists were collected, and drug concentrations were analysed in samples from 547 patients, half with uncontrolled hypertension, and all treated with ≥ 2 antihypertensive drugs. For sample preparation, ...