Improved insulin infusion set survival and faster insulin action are important issues for pump users and for the development of an artificial pancreas. The current recommendation is to change infusion sets every 3 days. Our objectives were to determine the effect of lipohypertrophy (LH) on infusion set survival and continuous glucose monitoring glucose levels.In this multicenter crossover trial, we recruited 20 subjects (age 28.1 ± 9.0 years) with type 1 diabetes (duration 17.5 ± 8.8 years) and an area of lipohypertrophied tissue3 cm. Subjects alternated weekly wearing a Teflon infusion set in an area of either LH or non-LH for 4 weeks. Sets were changed after (a) failure or (b) surviving 7 days of use.The least-squares mean duration of infusion set survival for sets that lasted7 days in lipohypertrophied tissue was 4.31 days compared with 4.12 days in nonlipohypertrophied tissue (P = 0.71). The average duration of set survival for individual subjects ranged from 2.2 to 7.0 days. Infusion sets in lipohypertrophied tissue failed due to hyperglycemia in 35% of subjects compared with 23% in nonlipohypertrophied tissue (P = 0.22). Both lipohypertrophied and nonlipohypertrophied tissues displayed a general increase in mean daily glucose after the third day of infusion set wear, but daily mean glucose did not differ by tissue type (P 0.38 on each day).LH did not significantly affect infusion set survival or mean glucose. Achieving optimal infusion set performance requires research into factors affecting set survival. Additionally, the recommendation for duration of set change may need to be individualized.
