Objective: To investigate the association between treatment induced change in continuous glucose monitored (CGM) time in range (TIR) and microalbuminuria in persons with type 1 diabetes (T1D) treated with sensor-augmented pumps (SAP).

Methods: In an open labelled controlled trial, 60 participants with T1D treated with multiple daily injections (MDI) and history of albuminuria were randomised to MDI- or SAP-therapy for 1 year. During the study, the SAP group wore a CGM (Enlite®, Medtronic). The MDI group wore blinded CGMs (Ipro2®, Medtronic) for 6 days at baseline and study end. Anthropometrics, CGM data, blood and urine samples were collected at 0, 1, 3, 6, 9, and 12-month visits. Based on CGM data collected between each visit, the percentage of time spent within 3.9-10.0 mmol/l (%TIR) was calculated. Urine albumin creatinine ratio (UACR) was measured in 3 samples at all visits. Only CGM data for the SAP group were included in the analysis. A linear mixed model with a participant-specific random intercept was used to analyse the effect of %TIR during 1 year after start of SAP on UACR, adjusting for changes in mean arterial pressure (MAP), HbA1c and body mass index.

Results: Twenty-six participants were assigned to the SAP group and had a baseline median (interquartile range) age of 51.5 (45.9; 62.1) years, HbA1c of 66 (58; 77) mmol/mol, UACR of 78.8 (37; 205) mg/g and 51Cr-EDTA-GFR 85.0 (73.0; 96.5) ml/min/1.73m2. From baseline to study end, the mean improvement (95% CI) in %TIR was 11.3 (6.0; 16.6) %, HbA1C was -14.4 (-17.5; -11.2) mmol/mol and UACR was -13 (-33; -22) %; all p<0.001. HbA1c decreased with 4.7 mmol/mol per 10% increase in %TIR (p<0.001). The UACR decreased with 13% per 10% increase in %TIR (p=0.038), with 15% per 10 mmol/mol decrease in HbA1c (p=0.071), and with 31 % per 10 mmHg decrease in MAP (p<0.001).

Conclusion: In this longitudinal study, treatment induced increase in CGM-derived %TIR were significantly associated with decrease in albuminuria in T1D.

Disclosure

A. Ranjan: None. S. Rosenlund: Employee; Self; Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk A/S. T.W. Hansen: None. P. Rossing: Advisory Panel; Self; Sanofi. Consultant; Self; Astellas Pharma Inc., AstraZeneca, Bayer Healthcare Pharmaceuticals Inc., Boehringer Ingelheim International GmbH, Gilead Sciences, Inc., Novo Nordisk A/S. Research Support; Self; Novo Nordisk A/S. Speaker’s Bureau; Self; Eli Lilly and Company. Stock/Shareholder; Self; Novo Nordisk A/S. S. Andersen: None. K. Nørgaard: Advisory Panel; Self; Abbott, Medtronic. Research Support; Self; Novo Nordisk A/S. Speaker’s Bureau; Self; Medtronic, Novo Nordisk A/S. Stock/Shareholder; Self; Novo Nordisk Inc.

Funding

Novo Nordisk Foundation (NNF17SA0031406); Medtronic A/S

© 2020 by the American Diabetes Association
2020
Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at http://www.diabetesjournals.org/content/license.