Could FreeStyle Libre^™ sensor glucose data support decisions for safe driving?

Abstract

AimMany countries require individuals with diabetes to adhere to standards regarding blood glucose testing in order to be granted or retain a driving licence. Currently, interstitial glucose results may not be used. The aim of this study was to determine whether interstitial glucose measurements using flash glucose‐sensing technology can provide additional information to augment safe driving.MethodsSensor data from two European studies (NCT02232698 and NCT02082184) of the FreeStyle Libre Glucose Monitoring System™ in insulin‐treated Type 1 and Type 2 diabetes, 241 and 224 participants respectively, were used to determine the frequency of a low interstitial sensor glucose result (< 3.9 mmol/l) up to 4 h subsequent to a daytime (07:00–21:00 h) capillary blood glucose result ≥ 5 mmol/l.ResultsWithin 4 h of a capillary blood glucose result ≥ 5 mmol/l a sensor glucose result of < 3.9 mmol/l occurred on 22.0% of occasions (2573 of 11 706 blood glucose readings) for those with Type 1 diabetes, and 8.4% of occasions (699/8352) for those with Type 2 diabetes; 13.8% (1610/11 628) and 4.4% (365/8203) within 2 h, and 10.0% (1160/11 601) and 3.1% (254/8152) within 1.5 h. Analysis of sensor glucose results 5–7 mmol/l demonstrated the glucose trend arrow descending on 14.7% (1163/7894, Type 1 diabetes) and 9.4% (305/3233, Type 2 diabetes) of occasions.ConclusionsSensor‐based glucose information with directional arrows has the potential to support assessment of safe glucose levels associated with driving and offers distinct advantages over blood glucose testing for individuals with Type 1 and Type 2 diabetes to concord with driving safety standards.

National Consensus in the use of the Flash Glucose Monitoring System in Portugal

“…Data has shown that trend arrows allow us to predict with accuracy what will happen in the next four hours, which has the potential to support assessment of safe glucose levels associated with driving. 28 The first postprandial hours and after insulin administration seem to be the moment where there may be less precision. 29 The precision of the two different systems -Dexcom G5 and FreeStyle Libre -seem to be similar.…”

Driving and diabetes: are the changes in the European Union licensing regulations fit for purpose?

“…Flash CGM was utilised in a blinded manner to demonstrate how hypoglycaemia can develop in people after they had demonstrated a satisfactory capillary blood glucose (>5 mmol/L is the recommended minimum for safe driving) after selected time intervals (Table 2). 35 CGM systems measure interstitial glucose and measurements obtained by CGM are currently not accepted by the DVLA as evidence of safe driving practice. The regulation states that 'blood' glucose measurements should be undertaken and not the interstitial tissue glucose concentration that is provided by CGM or flash glucose monitoring.…”

“…Two studies have shown how these might be useful to detect hypoglycaemia occurring while driving, particularly asymptomatic episodes. 35,36 Continuous and often automatic monitoring of glucose levels would provide information to drivers which would alert them to potentially dangerous downward trends. Perhaps with the technological advances that are progressing apace with CGM and flash glucose monitoring, glucose sensors could be integrated within the display panel of a vehicle to alert the driver to a progressive fall in glucose.…”

Technology: an increasingly important component in the management of diabetes

“…Rayman et al . , however, suggest that the FreeStyle Libre could support safer diabetes self‐management during driving, not by replacing but by prompting more frequent capillary glucose testing. Larger studies of longer duration are now indicated in high‐risk populations to evaluate the safety of both real‐time and intermittent glucose monitoring during driving.…”

“…At present in the UK, the Driver and Vehicle Licensing Agency requires people taking insulin to test their capillary glucose prior to driving and does not recognize interstitial glucose measurements. Rayman et al [9], however, suggest that the FreeStyle Libre could support safer diabetes selfmanagement during driving, not by replacing but by prompting more frequent capillary glucose testing. Larger studies of longer duration are now indicated in high-risk populations to evaluate the safety of both real-time and intermittent glucose monitoring during driving.…”