Hypoglycemia prevalence in prepubertal children with type 1 diabetes on standard insulin regimen: use of continuous glucose monitoring system

Abstract

Objective: To determine hypoglycemia prevalence in prepubertal children on thrice (TID) and twice (BID) daily insulin regimens, using the Medtronic Minimed Continuous Glucose Monitoring System.

Research design and methods: Twenty-eight children aged <12 years (median 9.8, range 6.9-11.8) wore the sensor for three consecutive days and nights. Hypoglycemia was defined as glucose <60 mg/dl for >15 min. Data are expressed as the percentage of time period spent hypoglycemic.

Results: Hypoglycemia prevalence was 10.1% (mean 2.6 h. subject(-1) x day(-1)). Hypoglycemia was more common at night compared with daytime (18.81 vs. 4.4%, P < 0.001); 78 and 43% of subjects showed hypoglycemia on at least one night and two or more nights, respectively. Nocturnal episodes were prolonged (median 3.3 h) and asymptomatic (91% of episodes). Prevalence was greater between 0400 and 0730 h than between 2200 and 0400 h (25.5 vs. 15.4%, P < 0.001). On a TID compared with a BID regimen, nocturnal hypoglycemia prevalence was reduced, particularly between 0400-0730 h (22.9 vs. 27.4%, P = 0.005), whereas hypoglycemia the following morning (0730-1200 h) was greater (7.8 vs. 2.8%, P < 0.001). Nocturnal hypoglycemia risk was associated with decreasing age (by a factor of 0.6 for a year less in age), increased insulin dose (by 1.6 for an increase of 0.1 units. kg(-1) x day(-1)), insulin regimen (by 0.2 on a BID compared with a TID regimen), and increased weight standard deviation score (SDS) (by 2.7 for a one SDS rise).

Conclusions: Use of standard insulin regimens results in high prevalence and large intraindividual variation in hypoglycemia, particularly at night. Independent risk factors for nocturnal hypoglycemia were younger age, greater daily insulin dose, insulin regimen, and increasing weight.