Bone Turnover Markers in Type 1 Diabetes

BTMs and sclerostin were measured among a subgroup of participants with T1D (n = 61) and controls (n = 57) who had their blood sampled in the morning before 10:00 am after a minimum 10-h fast. Serum samples were frozen at −80 °C until batch analysis at the study end. Serum CTX [CV <4%], P1NP [CV <2%], and N-MID osteocalcin [CV <2%] were measured by automated electrochemiluminescence immunoassay (Cobas e411, Roche Diagnostics). These measurements were performed at the Centre Hospitalier de l’Université de Montréal, a clinical laboratory with extensive experience in the measurement of BTMs. Serum sclerostin [CV 5%] was measured by ELISA using TECO kit, as per manufacturer’s protocol (Sclerostin TECO High Sensitive; TECOmedical Group).
All participants had PTH (Siemens Immulite 1000, Siemens Healthineers), 25OHD (Siemens Advia Centaur XPT, Siemens Healthineers; interassay CV 8%), and IGF-1 (Siemens Immulite 2000 xPi, Siemens Healthineers) measured by automated chemiluminescent immunoassay. Other biochemical tests were performed using standard automated techniques: HbA_1C, hemoglobin, creatinine, lipid profile, thyrotropin (TSH), serum total calcium, albumin, phosphate, anti-transglutaminase antibodies and immunoglobulin A, and spot urine albumin-to-creatinine ratio. eGFR was calculated using the Chronic Kidney Disease Epidemiologic Collaboration equation.²⁹ (link)