Assessment of Dose Selection Attributes with Audible Notification in Insulin Pen Devices

Abstract

Patients with type 2 diabetes often suffer from impairments in vision as well as manual dexterity. The purpose of this study was to assess the reliability of dose selection and setting of five insulin devices by patients using auditory and sensory confirmation. A total of 48 patients (30 men, 18 women; mean +/- SD age 60.5 +/- 14.0 years; hemoglobin A(1c) 8.7 +/- 1.9%) were randomized to test the following devices: NovoPen 3 (Novo Nordisk A/S, Bagsvaerd, Denmark), HumaPen Ergo (Eli Lilly, Indianapolis, IN), Humalog Pen (Eli Lilly), InnoLet (Novo Nordisk), and FlexPen(Novo Nordisk). Significantly more patients detected an auditory confirmation of dose setting when using the NovoPen 3 compared with the Humalog Pen (P < 0.001), HumaPen Ergo (P < 0.001), and InnoLet (P < 0.01). The audible click for the FlexPen was also heard by more patients than for the Humalog Pen (P < 0.001) and HumaPen Ergo (P < 0.01). All patients found that the Flex- Pen provided physical sensory confirmation; the percentage was higher than for those using the Humalog Pen (P < 0.001), HumaPen Ergo (P < 0.001), and InnoLet (P < 0.01). The NovoPen 3 was also associated with a higher percentage of patients who felt the click sensation than with the Humalog Pen (P < 0.001) and HumaPen Ergo (P < 0.01). Patients reported more confidence in setting the correct dose with the NovoPen 3 and FlexPen, and found these the most reliable for dose setting. Sound recordings showed that the NovoPen 3 produced the loudest clicks when setting a dose (P < 0.001 for all comparisons). The clarity of the click when setting a dose on an insulin delivery device can affect the patient's confidence in selecting the correct dose.