Background: Injecting insulin may cause pain and anxiety and lead to suboptimal treatment of diabetes mellitus. The aim of this randomized, open-label, crossover study was to compare two types of needle design and diameter in patients with diabetes injecting insulin.
Methods: Patients with diabetes injecting insulin twice daily for at least 3 months were included. A NovoFine (Novo Nordisk, Bagsvërd, Denmark) 32-gauge tip 6mm tapered needle and a Micro Fine Plus (Nippon Becton Dickinson Co. Ltd., Tokyo, Japan) 31-gauge 5mm standard needle were compared. Patients were randomized to use one needle for 1 week, followed by the alternative needle for another week. Before and after each week patients completed a 14-item questionnaire assessing overall satisfaction and usability of the needles. Each item was scored on a visual analog scale from -100 (worst) to +100 (best).
Results: Thirty patients (24 men, six women) took part in this study: 24 with type 2 diabetes and six with latent autoimmune diabetes in adults. The mean +/- SD for age was 57.8 +/- 7.6 years, for body mass index was 23.0 +/- 3.1 kg/m(2), for duration of diabetes was 15.6 +/- 9.8 years, and for mean glycated hemoglobin was 7.1 +/- 1.1%. Patients were more satisfied with the use of NovoFine 32-gauge tip 6mm needles (P < 0.0001), found the needles less frightening (P < 0.05) and less painful (P < 0.01), and caused less frequent bleeding and bruising (P < 0.001) than Micro Fine Plus 31-gauge 5mm needles.
Conclusions: These results suggest that the diameter and design of the needle play an important role in reducing injection pain and needle anxiety, which is particularly important for insulin initiation.