Optimizing insulin injection technique and its effect on blood glucose control

The purpose of the study is to assess whether proper Injection Technique (IT) is associated with improved glucose control over a three month period.

Patients (N = 346) with diabetes from 18 ambulatory centers throughout northern Italy who had been injecting insulin ≥ four years answered a questionnaire about their IT. The nurse then examined the patient's injection sites for the presence of lipohypertrophy (LH), followed by an individualized training session in which sub-optimal IT practices highlighted in the questionnaire were addressed. All patients were taught to rotate sites correctly to avoid LH and were begun on 4 mm pen needles to avoid intramuscular (IM) injections. They were instructed not to reuse needles.

Nearly 49% of patients were found to have LH at study entry. After three months, patients had mean reductions in HbA1c of 0.58% (0.50%-0.66%, 95% CI), in fasting blood glucose of 14 mg/dL (10.2-17.8 mg/dL, 95% CI) and in total daily insulin dose of 2.0 IU (1.4-2.5 IU, 95% CI) all with p < 0.05. Follow-up questionnaires showed significant numbers of patients recognized the importance of IT and were performing their injections more correctly. The majority found the 4 mm needle convenient and comfortable.

Targeted individualized training in IT, including the switch to a 4 mm needle, is associated with improved glucose control, greater satisfaction with therapy, better and simpler injection practices and possibly lower consumption of insulin after only a three month period.