Continuous Subcutaneous Insulin Infusion and Multiple Daily Injection Therapy Are Equally Effective in Type 2 Diabetes

Conclusions

This study reports the first data on the use of any insulin analog in CSII in patients with type 2 diabetes. This 24-week clinical trial compares CSII and MDI therapies in type 2 diabetes while using insulin aspart in both treatment groups. Previous studies of subjects with type 1 diabetes treated with insulin aspart have demonstrated its suitability in infusion pumps.^[13,14] Use of insulin aspart in CSII had a safety and efficacy profile that was comparable to buffered regular insulin and insulin lispro.^[14]

In this clinical trial, subjects with type 2 diabetes previously treated with limited insulin therapy had significant improvements in HbA_1c values when switched to intensive insulin treatment using CSII or MDI therapy. The decreases in HbA_1c values may have been even greater if OADs had been continued in the study. Improvements from baseline in eight-point BG profiles were consistent with the decreases in HbA_1c values for both groups.

The high rate of completion in both groups (90%) attests to the acceptability by patients with type 2 diabetes to initiate intensive insulin therapy using either CSII or MDI. It is noteworthy that subjects assigned to the CSII group were able to initiate intensive insulin therapy on an outpatient basis. Although both treatment groups had comparable glycemic control, the significant improvements in satisfaction scores by subjects in the CSII treatment group suggest that some patients with type 2 diabetes would benefit by using CSII to initiate intensive insulin therapy.

Patient acceptability and long-term compliance of either therapy was not determined beyond the 24 weeks of this study. However, the significantly higher satisfaction scores for convenience, ease of use, and overall satisfaction by the CSII-treated patients suggests that they will have greater treatment acceptance than MDI-treated patients and could consequently be more compliant over time.

In this study, the CSII group had a safety profile that was similar to the MDI group. The CSII group had 15 episodes of injection site reactions (redness or soreness) reported by eight subjects. All episodes were mild, resolved spontaneously, and did not result in the withdrawal of any subject from the study. The causative relationship of injection site reactions to insulin aspart was not likely because insulin aspart was also used in the MDI group, which reported no incidents.

The lower incidence of hyperglycemia for the CSII group (3 subjects, 6 events) compared with the MDI group (11 subjects, 26 events) may signal an advantage of insulin delivery by an infusion pump. Although the slightly higher incidence of hyperglycemia in the MDI group cannot be attributed solely to lack of compliance (missed injections) or possible once-daily NPH dosing by some MDI-treated subjects, it is noteworthy that CSII patients who are continuously wearing their infusion pumps have easier access to insulin and, thus, may be more compliant with treatment.

The rates of hypoglycemia in both treatment groups were low and consistent for patients with type 2 diabetes. All episodes of hypoglycemia were mild and easily managed by the study subject. Hypoglycemia was not an impediment to the subjects' achieving the treatment glycemic goals. Significantly lower rates of hypoglycemia have been reported by patients with type 2 diabetes who had implantable insulin pumps (~0.6 episodes per month) compared with MDI therapy (~1.8 episodes per month).^[8] However, the rate of episodes by CSII subjects in this study (0.8 ± 1.6 episodes per 30 days) was comparable to the rate achieved by the implantable insulin pump treatment group.

Subjects in this study reported an incidence of clogs and blockages similar to subjects with CSII-treated type 1 diabetes in a study comparing CSII use of insulin aspart, buffered regular insulin, and insulin lispro.^[14] Subjects in this trial were properly educated to monitor their BG levels and to recognize and correct the clogs and blockages, such that only one subject experienced a clog/blockage that coincided with a hyperglycemic episode.

Intensive insulin therapy for type 2 diabetes requires careful attention to insulin dosing, particularly during initiation of therapy. In the present study, the median insulin doses, both basal and bolus, were similar between treatment groups at baseline and increased only slightly for both groups by the end of the study. Therefore, subjects with type 2 diabetes were able to initiate and maintain intensive insulin therapy with CSII by using insulin doses similar to those used by the MDI group.

In conclusion, insulin aspart was a highly effective and compatible insulin for CSII using an external pump and was as safe and effective as MDI therapy for patients with type 2 diabetes initiating intensive insulin therapy. This study showed that patients can be trained to use pumps on an outpatient basis and that they greatly prefer CSII to insulin injections. The significantly greater satisfaction scores reported by CSII-treated subjects suggest that CSII may be the preferred method of intensive insulin therapy for capable patients with type 2 diabetes who desire optimal glycemic control.

We thank Ralph R. Turner, PhD, and Johanna F. Hayes, ScM (PHASE V Technologies, Wellesley Hills, MA); Marcia Testa, MPH, PhD (Harvard School of Public Health, Boston, MA); and Donald C. Simonson, MD (Brigham and Women's Hospital, Boston, MA) for providing the data collection, scoring, and analyses for the patient satisfaction component of this study.

The insulin aspart CSII study group in type 2 diabetes also included the following investigators: David Bell, MD (Birmingham, AL); Jaime Davidson, MD (Dallas, TX); Richard Guthrie, MD (Wichita, KS); Rajeev Jain, MD (Milwaukee, WI); Alan Marcus, MD (Laguna Hills, CA); Daniel Nadeau, MD (Bangor, ME); and Jay Skyler, MD (Miami, FL).

We recognize the following clinical trial coordinators for their technical assistance: Gail Baillargeon, Sarah Catton, Belinda Childs, Kim Davis, Donna Flanders, Stacy Frerichs, Marilyn Harper, Ramona Holliday, Debra Kasprzak, Sarah Kissel, Kelly McCulloch, Erica Pirtle, Laura Plummer, Aleida Saenz, Joyce Sinding, Tammy Stitch, Genene Streimer, and Marianne Vetrano.

Diabetes Care. 2003;26(9) © 2003 American Diabetes Association, Inc.

Cite this: Continuous Subcutaneous Insulin Infusion and Multiple Daily Injection Therapy Are Equally Effective in Type 2 Diabetes - Medscape - Sep 01, 2003.