Medication nonadherence, which is prevalent among patients with type 2 diabetes mellitus (T2DM), is associated with increased rates of mortality and hospitalization.1 A recent survey (2008) which included 500 patients with diabetes identified that 33% of patients have some level of dread associated with daily insulin injections and 57% of patients intentionally skip insulin injections.2 Insulin administration is an essential component of diabetes management for many patients, and pharmacists may help positively impact medication adherence by providing patient counseling and guidance about the importance of needle selection and appropriate injection technique.
Insulin should be administered into the subcutaneous tissue without reaching the muscle layer. Intramuscular administration, which more often occurs when administering insulin in the thigh, should be avoided to prevent the risk of rapid insulin absorption, which may result in hypoglycemia.3 As illustrated in Figure 1, inadvertent injection of insulin into the muscle fascia is more likely to occur with longer (8-mm, 12.7-mm) needles.4 Thus, selection of a needle of appropriate length is clinically important.
There is no medical reason to use needles longer than 6 mm for subcutaneous insulin injections.4 In a clinical study by Gibney and colleagues, which included obese patients with diabetes, it was estimated that over 99.5% of injections with 4-mm needles would result in successful subcutaneous injection when proper injection technique was followed.5 As shown in Figure 1, the 4-mm needle length is the optimal length to achieve a subcutaneous injection yet short enough to avoid an intramuscular injection. Because of safety and tolerability advantages over longer needles, shorter needles (ie, 4 mm, 5 mm, and 6 mm) are now recommended for use in children or adults, regardless of body mass index (BMI).4
Although current recommendations support shorter needle length, an increased awareness of the advantages of using shorter needles (6 mm or less) is needed. In a recent international survey (2009) of more than 4000 patients with type 1 or 2 diabetes mellitus (Insulin Injection Technique Questionnaire), more than half of adults (56%) who administer insulin were using an 8-mm or longer needle. In this same survey, 63% of patients had been using the same needle length since the time of their initial diagnosis.6
This suggests that a unique opportunity exists for pharmacists to evaluate patient knowledge and discuss the importance of needle selection for all patients who are administering insulin. In general, 4-mm needles can be used in almost all individuals, including children/adolescents and obese patients.7
Recommendations for Injection Technique
Injection sites for insulin include the upper arm, antero-lateral upper thigh, abdomen, and buttocks.5 Needles should be inserted at a straight-in, 90° angle to the skin surface. 4-mm and 5-mm needle lengths allow for a single-handed, no-pinch technique, which gives more patients the option to inject in their upper arm or buttocks. A skin pinch is recommended for needles 6 mm or longer.3,4,7 Patients should also be educated on the importance of rotating injection sites. Practical tips from the American Association of Diabetes Educators for minimizing pain during injection are shown in the Table (see below).
Meeting Patient Needs
Patients who inject insulin are concerned with comfort and ease of use. Also, patients with T2DM tend to have significantly lower hand strength versus control subjects without T2DM, regardless of age, as observed in a study by Cetinus et al.8 As discussed, selection of shorter needles is clinically important to help ensure proper injection of insulin into the subcutaneous layer. The BD Ultra-Fine™ Nano™ 4-mm × 32G Pen Needle is the shortest and thinnest pen needle available from BD, and it is compatible with all diabetes pens.* It is covered at the preferred copay by virtually all managed health plans, including Medicare Part D, although copays vary by plan.
There are important features beyond needle length that also distinguish pen needle products. BD Nano™ 4-mm Pen Needles now feature both PentaPoint™ Comfort and EasyFlow™ Technology. BD Nano™ Pen Needles with EasyFlow™ Technology have a larger lumen that allows for a 149% higher flow rate, making it easier for patients to press the pen button.9 BD PentaPoint™ Comfort Technology features the first, patented, 5-bevel needle tip for a more comfortable injection. A study comparing 5-bevel needles with 3-bevel needles determined that 23% less penetration force was required to penetrate the skin using BD Nano™ 4-mm Pen Needles.10 Patient-preferred BD Nano™ 4-mm Pen Needles have also been awarded the Ease-of-Use commendation by the Arthritis Foundation.11,12
Although the use of pen needles is growing, approximately 40% of all patients in the United States still inject with insulin syringes.13
BD Insulin Syringes with the BD Ultra-Fine™ 6-mm × 31G needle meet the needs of patients who use insulin syringes. It is the shortest needle available on an insulin syringe and its efficacy is equivalent to longer needles while being 53% shorter than the 12.7-mm needle (Figure 2).14
Role of the Pharmacist
Pharmacists can help positively impact medication adherence in patients who inject medications for the management of their diabetes. It is important for pharmacists to be aware of available products as well as best practices for injection. Interestingly, most patients have been using the same needle length since diagnosis,6 selected before current products became available. When these patients were asked to try using an insulin syringe with a 6-mm needle, over 80% of patients said they would prefer to use BD Insulin Syringes with the BD Ultra-Fine™ 6-mm needle over their current product.15 Shorter needles are less painful, easier to use, and preferred by most patients,11 and they are now recommended for use in children or adults on insulin therapy, regardless of BMI.4
Pharmacists can help by letting patients know about the available options. Several features distinguish the BD Nano™ 4-mm Pen Needle from other pen needles, including PentaPoint™ Comfort and EasyFlow™ Technology; these technologies help ensure ease of use, which may improve adherence to insulin therapy. Greater treatment adherence leads to more frequent patient visits to the pharmacy, allowing additional opportunities for pharmacists to provide patient counseling and guidance. To learn more about this subject, visit http://bd.com/us/diabetes/.
*As of August 2012
Ho PM, Rumsfeld JS, Masoudi FA, et al. Effect of medication nonadherence on hospitalization and mortality among patients with diabetes mellitus. Arch Intern Med. 2006;166(17):1836-1841.
Peyrot M, Rubin RR, Kruger DF, Travis LB. Correlates of insulin injection omission. Diabetes Care. 2010;33(2):240-245.
Saltiel-Berzin R, Cypress M, Gibney M. Translating the research in insulin injection technique: implications for practice. Diabetes Educ. 2012;38(5):635-643.
Frid A, Hirsch L, Gaspar R, et al; Scientific Advisory Board for the Third Injection Technique Workshop. New injection recommendations for patients with diabetes. Diabetes Metab. 2010;36(suppl 2):S3-S18.
Gibney MA, Arce CH, Byron KJ, Hirsch LJ. Skin and subcutaneous adipose layer thickness in adults with diabetes at sites used for insulin injections: implications for needle length recommendations. Curr Med Res Opin. 2010;26(6):1519-1530.
de Coninck C, Frid A, Gaspar R, et al. Results and analysis of the 2008-2009 Insulin Injection Technique Questionnaire survey. J Diabetes. 2010;2(3):168-179.
American Association of Diabetes Educators. Teaching injection technique to people with diabetes. http://www.diabeteseducator.org/export/sites/aade/_resources/pdf/research/InjectionEducationPracticeGuide.pdf. Published June 2013. Accessed July 2013.
Cetinus E, Buyukbese MA, Uzel M, Ekerbicer H, Karaoguz A. Hand grip strength in patients with type 2 diabetes mellitus. Diabetes Res Clin Pract. 2005;70(3):278-286.
Aronson R, Gibney MA, Oza K, et al. Insulin pen needles: effects of extra-thin wall needle technology on preference, confidence, and other patient ratings. Clin Ther. 2013;35(7):923-933.
Hirsch L, Gibney M, Berube J, Manocchio J. Impact of a modified needle tip geometry on penetration force as well as acceptability, preference, and perceived pain in subjects with diabetes. J Diabetes Sci Technol. 2012;6(2):325-335.
Hirsch LJ, Gibney MA, Albanese J, et al. Comparative glycemic control, safety and patient ratings for a new 4 mm × 32G insulin pen needle in adults with diabetes. Curr Med Res Opin. 2010;26(6):1531-1541.
Arthritis Foundation. BD Nano™ 4mm Pen Needles. www.arthritis.org/resources/ease-of-use-new/health-and-wellness/bdnano-4mm-pen-needles. Accessed July 2013.
Wolters Kluwer, National Trx Data, July 2012-June 2013. Data on file, Becton, Dickinson and Company.
Schwartz S, Hassman D, Shelmet J, et al. A multicenter, open-label, randomized, two-period crossover trial comparing glycemic control, satisfaction, and preference achieved with a 31 gauge × 6 mm needle versus a 29 gauge × 12.7 mm needle in obese patients with diabetes mellitus. Clin Ther. 2004;26(10):1663-1678.
Data on file, Becton, Dickinson and Company.