Page 259 - Glucose Monitoring Devices

266 CHAPTER 13 Low glucose suspend systems

P ¼.006) [39]. These clinical trial data led the FDA approval of the LGS system
(known as 530G) in the United States in 2013. The predetermined threshold for
insulin pump suspension approved by the US FDA was 60e90 mg/dL depending
on the patient and/or provider preference. It is also important to know that this is
the first study suggesting that hypoglycemia is an independent risk factor for future
hypoglycemic episodes in patients with T1D [28]; thus, the cross-over study design
may not be the most appropriate study design for devices that are being evaluated for
hypoglycemia reduction because of the possible spillover effect of hypoglycemia
occurred during the first half of the cross-over period. This pivotal study was
followed by a large, multicenter, randomized trial (ASPIRE In-Home) in patients
with T1D [40]. The ASPIRE In-Home randomly assigned 247 patients with T1D
(age range 16e70 years) to receive either the LGS feature or sensor-augmented
insulin pump therapy for 3 months. The mean area under the curve for nocturnal
hypoglycemic events was 37.5% lower in the LGS group compared to the control
group. Similarly, nocturnal hypoglycemic events occurred at 31.8% less frequently
in the LGS group than in the control group [40].
Despite a number of clinical trials establishing the safety of the LGS system in
reducing the severity of hypoglycemia in patients with T1D, there was a potential
concern related to suspension of insulin delivery for 2 h due to a failing sensor
when blood glucose levels were not actually low, which may result in hyperglyce-
mia and/or ketoacidosis. A small study of 17 participants with T1D showed no
clinically significant differences in blood ketone levels between suspend nights
compared to nonsuspend nightsdeven in the absence of low glucosed
demonstrating the safety of LGS systems in real-life situations even when sensor
glucose may not be accurate [41].
A prospective study from Egypt looked at the effect of the LGS system on the
frequency of hypoglycemia in adolescents with T1D who desired to fast during
Ramadan [42]. Ramadan is a sacred month of the year in Islamic culture where
people refrain from eating, drinking, and using oral medications from predawn to
sunset. Diabetes management during Ramadan could be challenging and difficult,
especially in people with T1D or T2D requiring insulin therapy [43]. The risk of
hypoglycemia increases during the Ramadan fast, and it is the most disliked compli-
cation as its treatment signifies the intake of carbohydrates, resulting in premature
fast breaking, which produces a sense of guilt and failure in faithful individuals.
Therefore, using technology that can reduce the risk of hypoglycemia and maintain
glycemic control is of utmost importance during this period. In the study, the safety
and efficacy of LGS systems during Ramadan was evaluated among 25 adolescents
with T1D who used LGS features compared to 35 adolescents with T1D who used
the sensor but turned off the LGS feature [42]. Compared with the group with the
LGS feature off, the use of the LGS feature significantly reduced the number of
both hypo- and hyperglycemic excursions [42]. There were about four LGS events
per patient per day recorded, the mean duration of LGS events was 26.5 min, and
most LGS events occurred between 4 and 7 p.m., a few hours before the end of
fasting.