LOSS OF GLYCEMIC CONTROL OVER TIME AFTER INFUSION LINE CHANGE IN PATIENTS WITH TYPE 1 DIABETES TREATED WITH CONTINUOUS SUBCUTANEOUS INSULIN INFUSIONS.

Abstract

Purpose of Study Continuous subcutaneous insulin infusion (CSII) is a well-established modality for treating patients with type 1 diabetes mellitus. The current recommendations, based on anecdotal data, are to change the pump infusion every 48 hours. We report here an analysis of a substudy from 12 patients in a randomized, controlled, crossover study comparing insulin aspart and insulin lispro among subjects with type 1 DM treated with CSII. The aim of this substudy was to determine the optimal duration of a pump infusion line, without loss of glycemic control. Methods Used Data from 12 patients (M = 2, F = 10; mean age 43 years, HbA1c 7.4 ± 0.4%) were analyzed. A continuous glucose monitoring system (CGMS) was inserted between 24 to 48 hours after a pump infusion line change and continued for 3 days. Site infection and/or blood sugar > 300 mg/dL were predetermined reasons for terminating the study. The time intervals reported were in relation to the time of line change. Summary of Results Data downloaded from the CGMS were pooled and then analyzed using the paired t-test. Interstitial fluid glucose between 70 and 180 mg/dL was defined as being within target range, whereas those above 180 mg/dL were defined as above range. From the point of line change, data were analyzed for difference between days 2 (from 24-48 hours after line change), 3 (from 48 to 72 hours after line change), 4 (from 72-96 hours after line change), and 5 (from 96-100 hours after the line change). There was a statistically significant increase in the percentage of time spent above range between days 2 and 3 (p = .027, CI 1.3-17.5), and days 3 and 4 (p = .027, CI 1.2-16.4). Statistically significant differences were also present for the average blood sugar between days 2 and 3 (p = .001, CI 12.4-29.0) and days 3 and 4 (p = .026, CI 2.1-26.9). Conclusions Glycemic control in patients with type 1 diabetes treated with CSII begins deteriorating 24 hours after a change in the infusion line. Since this may limit optimal control in pump-treated patients, strategies need to be developed to improve longevity of the infusion systems. Patient education on frequent line change is essential.