Saponaro F, et al. - In the present study, researchers assessed the levels of vitamin D (VitD) in patients with heart failure (HF) vs a control group. They also evaluated the impacts of VitD on HF outcome and compared VitD measurement between LIAISON immunoassay and HPLC-MS-MS methods in this population. According to the findings, 25OHD levels adequately measured by HPLC-MS-MS were low in the HF population and were associated with HF-related risk of death. LIAISON and HPLC-MS-MS has good agreement, but the prevalence of VitD insufficiency was significantly higher with the former vs the latter method.