Abstract
Injectable insulin therapy is a valuable therapeutic option for millions of people with diabetes worldwide. However, many people with diabetes undergoing insulin therapy experience suboptimal outcomes and/or have complications because of inadequate injection technique and training. Practical, current, evidence-based recommendations are mandatory for primary care practitioners and diabetes specialists alike to address unmet needs in insulin injection technique, education, and consequent outcomes. The most recent global insulin injection technique best practices were published in 2016 by the Forum for Injection Technique and Therapy Expert Recommendations (FITTER). While injection technique efforts in different regions have reflected some developments since 2016, a global effort was warranted to comprehensively capture new evidence and modern expert perspectives. In this article, we share the output of the “FITTER Forward” initiative, authored by 16 diabetes specialists from 13 countries who met virtually in 2023-2024. FITTER Forward provides an updated rationale for the importance of proper injection technique training and its impact on diabetes management. The FITTER Forward recommendations are organized for use in clinical practice and include 4 sections describing (1) the foundational science informing injection device design, experiences, and outcomes, (2) proper injection technique procedures for insulin pens and syringes from insulin storage to needle disposal, (3) lipodystrophy risk reduction, with a focus on lipohypertrophy, and (4) structured injection technique training programs for people with diabetes. Overall, FITTER Forward aims to better equip health care professionals to advance diabetes care by empowering people with diabetes and their caregivers to correctly and safely deliver insulin.
Abbreviations and Acronyms
BMI
body mass index
FITTER
The Forum for Injection Technique and Therapy Expert Recommendations
GLP-1
glucagon-like peptide 1
HCP
health care professional
IM
intramuscular
ITQ
Injection Technique Questionnaire
PWD
people with diabetes
SC
subcutaneous
One hundred years after its initial therapeutic use, insulin remains critical to diabetes care, with approximately 150 to 200 million people with diabetes (PWD) worldwide requiring insulin treatment.1,2 Insulin should be delivered to the subcutaneous (SC) tissue by injection or infusion for best absorption into the bloodstream and subsequent glucose-lowering activity.3,4 People with diabetes and/or their caregivers are therefore tasked to learn optimal, evidence-based techniques to deliver insulin as part of daily life.5 Unfortunately, insulin delivery technique education is often neglected. In the 2015 Injection Technique Questionnaire (ITQ) surveying more than 13,000 PWD from 42 countries, less than 40% of respondents reported receiving injection instructions from their health care professionals (HCPs) within the preceding 6 months.6,7 In the ITQ, inadequate injection technique was common, and multiple recent reports revealed that all surveyed PWD made at least one insulin injection technique error.6, 7, 8, 9 Technique errors may lead to undesirable glycemic outcomes, excess pain, or skin complications such as lipodystrophy.5, 6, 7,10 Fortunately, injection technique educational programs can improve patient satisfaction and reduce insulin requirements as well as the frequency of hypoglycemic events, glucose variability, and risk of lipodystrophy.11, 12, 13, 14, 15, 16, 17
The Forum for Injection Technique and Therapy Expert Recommendations (FITTER) group, comprised of physicians, nurses, diabetes educators/certified diabetes care and education specialists, and allied HCPs, previously created an evidence-based resource (referred to herein as FITTER) for insulin delivery technique via a workshop in 2015, which expanded on prior workshops and incorporated the aforementioned ITQ results (Supplemental Figure 1, available online at http://www.mayoclinicproceedings.org).5,18,19 FITTER became a landmark reference for insulin delivery technique and is cited in the American Diabetes Association Standards of Care as best practice.5,20 Since 2015, regional-specific iterations of FITTER and other initiatives such as the Forum for Injection Technique have emerged as valuable resources.21, 22, 23 These regional efforts serve to adapt recommendations to unique local needs (eg, highlighting challenges for low- or middle-income countries). Now, nearly a decade since FITTER was published, an update is warranted to reflect the latest technological and research advancements.
Our new group, known as FITTER Forward, convened virtually in 2023-2024 to create an updated reference for HCPs, PWD, and their caregivers on optimal insulin delivery, with a focus on injection technique. This effort revises prior recommendations and shares new insights on injection education program design. We also sought to improve the practical utility of the recommendations with a new organization of content and new figures/tables. Overall, our goal was to highlight the measurable value of proper insulin delivery technique for improving clinical outcomes and reducing unwanted adverse effects.
Methods
Sixteen diabetes experts from 13 countries (list in Supplemental Table 1, available online at http://www.mayoclinicproceedings.org) held 4 virtual sessions from September 26, 2023, to June 28, 2024, to review (1) the recommendations from the last FITTER5; (2) recent literature on injection technology (eg, new pen needle designs/lengths) and educational programs; and (3) practical teaching tools for injection technique. Meeting virtually offered ease of scheduling, reduced carbon footprint, and improved ability to share references/photos digitally. The output of the virtual meetings combined with literature reviews of the aforementioned topics have informed the FITTER Forward recommendations. The present recommendations pertain largely to injection technique for adults, with adaptation specific to children/adolescents. A brief summary of insulin infusion considerations has been included in Supplemental Table 2 (available online at http://www.mayoclinicproceedings.org).