We harvested blood samples very early in the course of SCA, during which elevated levels of copeptin most likely will reflect the stress response associated with CA, rather than hemodynamic instability signaling a poorer prognosis after ROSC, such as in samples harvested up to 6 h after hospital admission in the FINNRESUSCI population (16). The gene discussed is AVP; the disease is autosomal dominant cerebellar ataxia.