Aim: To examine factors associated with insulin injection omission/non-adherence on a global basis.
Methods: Telephone survey of 1530 insulin-treated adults with self-reported diabetes (110 type 1 and 1420 type 2) in China, France, Japan, Germany, Spain, Turkey, UK or USA. Participants had a mean age of ∼60 years, ∼15 years duration of diabetes and ∼9 years duration of insulin treatment. Regression analysis assessed the independent associations (p < 0.05) of country, participant characteristics and treatment-related beliefs/perceptions with number of days in the past month that an insulin injection was missed or not taken as prescribed.
Results: One third (35%) of respondents reported one or more days (mean: ∼3 days) of insulin omission/non-adherence. Insulin omission/non-adherence differed widely across countries (range = 20-44%); differences in days of insulin omission/non-adherence were maintained after adjustment for other risk factors. Most risk factors had similar relationships with insulin omission/non-adherence across countries (few interactions with country). Insulin omission/non-adherence was more frequent among respondents who were male, younger, had type 2 diabetes or more frequent hypoglycaemia, were less successful with other treatment tasks, regarded insulin adherence as less important, had more practical/logistical barriers and difficulties with insulin adherence, were concerned that insulin treatment required lifestyle changes or were dissatisfied with the flexibility of injection timing.
Conclusions: The results of this large-scale study suggest that insulin omission/non-adherence is common and associated with several modifiable risk factors (including practical barriers, injection difficulties, lifestyle burden and regimen inflexibility). Additional efforts to address these risk factors might reduce the frequency of insulin omission/non-adherence and lead to improved clinical outcomes.
Keywords: diabetes mellitus; drug compliance; drug utilization; insulin therapy; observational study.
© 2012 Blackwell Publishing Ltd.