The effect of short-term use of the Guardian RT continuous glucose monitoring system on fear of hypoglycaemia in patients with type 1 diabetes mellitus

Aim: This study examines whether the short-term use of a continuous glucose monitor (CGM) can reduce the fear of hypoglycaemia in individuals with type 1 diabetes mellitus (T1DM). Methods: Twelve participants with T1DM were fitted with a Guardian REAL-Time CGM and assigned to either. an alarm (low glucose alarm set at 4.5 mmol/L) or no alarm condition for 3 days, with both treatments administered following a counterbalanced study design. The participants completed the Hypoglycaemia Fear Survey on three separate occasions, before their CGM was fitted as well as following the alarm and no alarm conditions. Results: The alarm treatment reduced the incidence of hypoglycaemic episodes (CGM readings <= 3.5 mmol/L; 1.1 +/- 0.5 versus 1.9 +/- 0.5; mean +/- SEM) and the relative time spent below this hypoglycaemic threshold (0.9 +/- 0.4% versus 2.6 +/- 1.0%) but did not alter the fear of hypoglycaemia (78.6 +/- 7.0, 75.8 +/- 5.2 and 79.3 +/- 5.8 at baseline and following the alarm and no alarm treatments, respectively; p > 0.05). CGM overestimated blood glucose levels by 0.8 +/- 0.2 mmol/L for blood glucose readings less than, or equal to, 5 mmol/L. Conclusions: Short-term use of the Guardian REAL-Time CGM has no clinically significant effect on fear of hypoglycaemia possibly due, in part, to the inaccuracies of CGMs at low blood glucose levels. (C) 2011 Primary Care Diabetes Europe. Published by Elsevier Ltd. All rights reserved.