Performance of an Electronic Diary System for Intensive Insulin Management in Global Diabetes Clinical Trials

Abstract

Background: This report describes the performance of a wireless electronic diary (e-diary) system for data collection and enhanced patient-investigator interactions during intensive insulin management in diabetes clinical trials.

Materials and methods: We implemented a customized electronic communication system featuring an e-diary and a Web portal in three global, randomized, controlled Phase 3 clinical trials testing basal insulin peglispro compared with insulin glargine, both combined with prandial insulin lispro, in patients with type 1 or type 2 diabetes mellitus (T1DM and T2DM, respectively). We collected data during 28 weeks of study e-diary use for the report.

Results: Patients (n=2,938) in 31 countries used e-diaries to transmit 2,439,087 blood glucose (BG) values, 96% of which were associated by the patient with a protocol time point during the 72-h response window. Of 208,192 hypoglycemia events captured, 96% had a BG value, and 95% had treatments and outcomes entered by patients within the 72-h window. Patients recorded administration of 1,964,477 insulin doses; 93% of basal insulin doses were adherent with the investigator prescription. Investigators adjusted 13 basal and 92 bolus insulin prescriptions per patient-year using the e-diary system. After 26 weeks of treatment and e-diary use in the combined study arms, hemoglobin A1c values decreased by 0.6% or 1.6% and fasting BG decreased by 7.8 or 28 mg/dL in patients with T1DM or T2DM, respectively.

Conclusions: The e-diary system enabled comprehensive data collection and facilitated communication between investigators and patients for intensive insulin management in three global clinical trials testing basal insulins.

FIG. 1.

Insulin management with the electronic system. Using the glucose meter, the patient determines blood glucose and transfers the value to the electronic diary (e-diary). Using the e-diary, the patient enters the meal (breakfast, lunch, or dinner) and the carbohydrate to be consumed. On request, the e-diary recommends a dose based on the prescription (units/g of carbohydrate and units/blood glucose deviation). The patient enters the actual dose administered. On the StudyWorks site portal, the investigator receives the data as they are transferred from the e-diary. The site evaluates the insulin prescription weekly and determines if an adjustment is needed in basal or bolus insulin. The investigator uses the insulin algorithms programmed in StudyWorks to make the changes, and the system notifies the patient via a message on the e-diary. The patient responds that the message was read.

FIG. 2.

Frequency histograms of blood glucose values and mean hemoglobin A1c (HbA1c) and fasting blood glucose (FBG) values during the study: (A) frequency distribution of all BG values collected via the e-diaries during the 28-week period from both study arms, by type of diabetes, and (B) outcome data by type of diabetes for all patients in both treatment arms. At each time point shown, the patients visited the sites and had blood drawn for HbA1c determination. The concurrent FBG number was calculated for each patient as the mean of pre-breakfast SMBG measurements on the previous 7 days. Each data point represents the mean of all patients at that time point for HbA1c or FBG. T1DM, n=1,534 and 1,522 at baseline for HbA1c and FBG, respectively. For type 2 diabetes mellitus (T2DM) patients, n=1,356 and 1,343 at baseline for HbA1c and FBG, respectively. T1DM, type 1 diabetes mellitus.