Kryptor compact plus device

Fasting plasma copeptin concentration was measured by using a KRYPTOR Compact Plus device and commercially available chemiluminescence sandwich immunoassay copeptin ProAVP kit with coated tubes from samples stored at −80°C (BRAHMS Copeptin proAVP KRYPTOR; ThermoFisher Scientific). All other plasma laboratory analyses were performed at the certified University Hospital’s central clinical laboratory. This included measurement of glucose (COBAS, Roche Diagnostics, Rotkreuz, Switzerland), creatinine, sodium, potassium, urea, osmolality, hematocrit, and C-reactive protein. Urine osmolality was measured in 24-hour urine samples at the clinical site by using an i-Osmometer basic (Löser, Speyer, Germany). The 24-hour urine collections followed procedures developed at the Department of Endocrinology, Skåne University Hospital Malmö, Sweden, and consisted of a comprehensible written instruction aimed at ensuring accurate and complete collection of urine.

Fasting plasma copeptin concentration was measured using a KRYPTOR Compact Plus device and commercially available chemiluminescence sandwich immunoassay copeptin ProAVP kit with coated tubes from samples stored at − 80 °C (Thermo Scientific BRAHMS Copeptin proAVP KRYPTOR). Blood glucose was measured using a HemoCue Glucose 201⁺ Analyzer at the research unit. All other plasma and blood laboratory analyses were performed at the University Hospital’s central clinical laboratory in Malmö, and included fasting plasma measurements of lipids, fasting blood HbA_1c and fasting plasma creatinine. HbA_1c was measured in n = 1482 out of 2599 participants as this measurement was added on to the baseline investigation at a later stage.
U-osm in morning urine samples was measured in n = 1509 of the study participants at the research unit using an i-Osmometer basic (Löser, Germany).