Serum calcification propensity in type 1 diabetes associates with mineral stress

Aims: Increased vascular calcification could be an underlying mechanism of cardiovascular complications in type 1 diabetes mellitus (T1DM). Calcification propensity can be monitored by the maturation time of calciprotein particles in serum (T-50 test). A high calcification propensity (i.e. low T-50-value) is an independent determinant of mortality in various populations. Aim was to investigate T-50 levels with indices of calcium metabolism and disease status in T1DM patients. Methods: As part of a prospective cohort study, T1DM patients were examined annually. At baseline T-50 was determined in 216 (77%) patients (57% male) with a mean age of 45 (12) years, diabetes duration 22 [15.8, 30.4] years and HbA1c of 60 (12) mmol/mol (7.6 (1.0) %). Baseline data were collected in 2002 and follow-up data were collected in 2018. Results: The T-50 time was normally distributed with a mean of 339 (60) minutes. Patients in the highest tertile of T-50 (range 369-466) were older, had lower phosphate and PTH and higher magnesium and vitamin D concentrations as compared to the middle (range 317-368) and lowest (range 129-316) tertiles, while eGFR was comparable between groups. During follow-up of 15 years, 43 patients developed a macrovascular complication and 26 patients died. In regression analysis, T-50 was not a prognostic factor for the development of complications or mortality. Conclusions: The T-50 time was associated with indices of increased mineral stress, but not with the development of long-term macrovascular complications. (C) 2019 Elsevier B.V. All rights reserved.