Comparison of usability and patient preference for insulin pen needles produced with different production techniques: "thin-wall" needles compared to "regular-wall" needles: an open-label study

Needle Technology for Insulin Administration: A Century of Innovation

Innovations in syringe and pen needle (PN) technology over the last 100 years have led to important advances in insulin delivery for people with diabetes, paralleling the strides made in developing recombinant DNA human insulin and insulin analogs with varying onset and duration of action. In this review, the history of advances in insulin delivery is described, focusing on progress in syringe, needle, and PN technologies. The early glass and metal syringes that required sterilization by boiling have been replaced by disposable, single-use syringes or pens with clear labeling for precise insulin dosing. The early needles ranging in length from 19 to 26 mm that required manual sharpening against a whetstone have been replaced by syringe needles of 6 mm and PNs of 4 mm in length as slender as 34 gauge. Imaging studies using ultrasound and computed tomography measured the thickness of skin and subcutaneous tissue layers to show feasibility of targeted insulin administration with shorter needles. These developments, coupled with innovations in needle/PN wall and tip structure, have led to improved injection experience for people with diabetes. It is also important to acknowledge the role of injection technique education, together with these advances in injection technology, for improving clinical outcomes and patient satisfaction. With continued projected growth of diabetes prevalence, particularly in developing countries where expensive and complex insulin delivery systems may not be practical, insulin syringes and pens will continue to serve as reliable and cost-effective means of insulin delivery for people with diabetes.

Needle-free injection of basal insulin improves fasting glucose variability as assessed by continuous glucose monitoring in T2DM: a prospective randomized multicenter open-label crossover study

BACKGROUND

Fasting glucose variability (FGV) extensively promotes the onset and development of diabetic complications. This study aimed to evaluate the FGV in type 2 diabetes mellitus (T2DM) patients administered basal insulin using a needle-free insulin injector (NFII).

RESEARCH DESIGN AND METHODS

This was a prospective randomized multicenter open-label crossover study. We randomly assigned 48 T2DM patients to receive basal insulin by NFII or conventional insulin pen (CIP) for 7-14 days and were then crossed over after washout. We conducted continuous glucose monitoring to investigate the FGV, our primary outcome was a composite parameter of the FGV with a fasting blood glucose target between 4.4 and 6.1 mmol/L.

RESULTS

The coefficient of variation for sensor glucose at 6 a.m. with CIP was 11.67 (8.70,14.81)% vs. 9.48 (6.48,12.24)% with NFII (p = 0.003), and the coefficient of variation for mean sensor glucose at 5-6 a.m. with CIP was 12.70 (9.17,16.56)% vs. 9.23 (7.01,11.98)% with NFII (p < 0.001). The overall basal insulin dosage with CIP injection was 18.00 (16.00, 20.00) IU vs. 16.00 (12.00, 19.00) IU during NFII (p < 0.003).

CONCLUSION

Compared with CIP, the use of the NFII to inject basal insulin improved FGV in T2DM.

CLINICAL TRIAL REGISTRATION

https://www.chictr.org.cn Identifier is ChiCTR2000034674.

Diabetes Technology Meeting 2021

Diabetes Technology Society hosted its annual Diabetes Technology Meeting on November 4 to November 6, 2021. This meeting brought together speakers to discuss various developments within the field of diabetes technology. Meeting topics included blood glucose monitoring, continuous glucose monitoring, novel sensors, direct-to-consumer telehealth, metrics for glycemia, software for diabetes, regulation of diabetes technology, diabetes data science, artificial pancreas, novel insulins, insulin delivery, skin trauma, metabesity, precision diabetes, diversity in diabetes technology, use of diabetes technology in pregnancy, and green diabetes. A live demonstration on a mobile app to monitor diabetic foot wounds was presented.

Consensus on Choice of Insulin Pen Devices in Routine Clinical Practice in India

Although insulin delivery devices are widely used by the patients, there is a paucity of published guidelines to help professionals manage their patients in insulin therapies. To provide simple and easily implementable guidelines to health care physicians on the choice of insulin delivery devices in routine clinical practice, experts in diabetes gathered together and discussed the recommendations at the National insulin Summit 2018. An ideal insulin delivery device should accurately deliver the prescribed dose of insulin and be easy to use. Recommendations are: (1) insulin should be initiated by using an insulin device if the patient seems to discontinue insulin therapy. (2) Pen devices offer accurate dosing than a syringe and vial and are associated with cost savings in the long term. (3) Switching over from syringes and vial to disposable pen devices improves adherence. (4) FlexPen^® offers better accuracy, and it requires lower dose force and injection force than SoloStar^® and KwikPen^® (5). Durable delivery pens such as NovoPen^® 4 maintain accuracy and low dose force compared with vials and syringes. (6) One pen should be used by only one patient. (7) Regular counseling on the proper use of the pen device is required regularly. This consensus-based recommendation is a useful reference tool for health care practitioners to initiate insulin therapy in patients with diabetes by using the appropriate insulin pen device.

LBEC0101, an etanercept biosimilar for the treatment of rheumatoid arthritis

Introduction: Treatment of rheumatoid arthritis (RA) has been revolutionized by the introduction of biologic disease-modifying antirheumatic drugs, such as tumor necrosis factor (TNF) inhibitors. With patent expiry approaching for many expensive biologic molecules, such as etanercept, more affordable biosimilar drugs are being developed. LBEC0101 is an etanercept biosimilar approved in Japan and South Korea for all etanercept indications including RA. Areas covered: We discuss the pharmacological characteristics, pharmacokinetics, efficacy, and safety of LBEC0101 compared with the etanercept reference product (ETN-RP). Preclinical studies showed that the binding affinity to TNFα and biological activity of LBEC0101 were similar to those of the ETN-RP. The pharmacokinetic profile of LBEC0101 was also similar to that of the ETN-RP. A Phase III, randomized, double-blind, 54-week study showed that the efficacy of LBEC0101 was equivalent to that of the ETN-RP in RA patients. An extension study showed that efficacy was sustained long-term in patients receiving LBEC0101 and in those switching from the ETN-RP to LBEC0101. The safety profile of LBEC0101 was also confirmed to be comparable with the ETN-RP. Expert opinion: LBEC0101 has shown equivalent pharmacokinetics and efficacy and comparable safety to the ETN-RP, and the lower cost of LBEC0101 provides a good cost-benefit ratio.

Toward a new age of patient centricity? The application of eye-tracking to the development of connected self-injection systems

BACKGROUND

Increasing interest in digitally enhanced drug delivery tools urges both industry and academia to rethink current approaches to product usability testing. This article introduces mobile eye-tracking, generating detailed contextual data about user engagement with connected self-injection systems as a new methodological approach to formative usability assessment.

METHODS

A longitudinal case study with a total of 35 injection-naïve participants was conducted. In three consecutive experiments, eye-tracking was applied to formative usability testing of a novel connected self-injection device. Three eye-tracking derived usability indicators were established to assess product effectiveness, efficiency, and ease of use.

RESULTS

Analysis of the data revealed events of user hesitation, process interruption and unintended action, and these occurrences could either be completely eliminated or significantly reduced throughout the process (product effectiveness). At the same time, the overall use duration decreased from 86.1 to 58.7 sec (product efficiency). Analysis revealed that product modifications successfully guided user attention to those interface elements most relevant during each task, thereby improving product ease-of-use.

CONCLUSIONS

The step-wise improvement in the usability indicators demonstrates that iteratively applying eye-tracking methods effectively supports the user-centered design of connected self-injection systems. The results highlight how eye-tracking can be employed to gain an in-depth understanding of patient engagement with novel healthcare technologies.

Pen devices for self-injection: contrasting measured injection force with users' perceived ease of injection

OBJECTIVES

Past research has emphasized injection force as a clinically highly relevant technical attribute of pen devices. However, little work has been conducted to relate these results to in-use studies. This article explores whether and how differences in pen injection force profiles influence users' self-reported perceived ease of injection and preferences.

METHODS

Three different pen systems were subjected to measurements of injection force using an automated mechanical set-up followed by a simulated use study where users assessed perceived ease of injection.

MAIN OUTCOMES MEASURE

Outcomes were measured by fitting data of measured injection force and perceived ease of injection using a linear model.

RESULTS

Although mechanical testing revealed significant differences between the three pen's measured injection forces these differences were not directly perceived by users in simulated injection studies.

CONCLUSION

The article bridges literature on injection force measurement and simulated use. It reveals how users' perceived ease of injection is less sensitive to measured injection forces than prior research has assumed. Thus, future research should holistically integrate patient feedback in new device development. Key limitations of this work are the low number of participants in the simulated use study and the fact that the ease of injection was assessed indirectly.

New Insulin Delivery Recommendations

Many primary care professionals manage injection or infusion therapies in patients with diabetes. Few published guidelines have been available to help such professionals and their patients manage these therapies. Herein, we present new, practical, and comprehensive recommendations for diabetes injections and infusions. These recommendations were informed by a large international survey of current practice and were written and vetted by 183 diabetes experts from 54 countries at the Forum for Injection Technique and Therapy: Expert Recommendations (FITTER) workshop held in Rome, Italy, in 2015. Recommendations are organized around the themes of anatomy, physiology, pathology, psychology, and technology. Key among the recommendations are that the shortest needles (currently the 4-mm pen and 6-mm syringe needles) are safe, effective, and less painful and should be the first-line choice in all patient categories; intramuscular injections should be avoided, especially with long-acting insulins, because severe hypoglycemia may result; lipohypertrophy is a frequent complication of therapy that distorts insulin absorption, and, therefore, injections and infusions should not be given into these lesions and correct site rotation will help prevent them; effective long-term therapy with insulin is critically dependent on addressing psychological hurdles upstream, even before insulin has been started; inappropriate disposal of used sharps poses a risk of infection with blood-borne pathogens; and mitigation is possible with proper training, effective disposal strategies, and the use of safety devices. Adherence to these new recommendations should lead to more effective therapies, improved outcomes, and lower costs for patients with diabetes.

Injection Technique and Pen Needle Design Affect Leakage From Skin After Subcutaneous Injections

BACKGROUND

After a subcutaneous injection fluid might leak out of the skin, commonly referred to as leakage or backflow. The objective was to examine the influence of needle design and injection technique on leakage after injections in the subcutaneous tissue of humans and pigs.

METHOD

Leakage data were obtained from a post hoc analysis of clinical trial data and from a pig study. Data from the clinical study were used to determine leakage as a function of injection volume, speed and region. Data from the pig study were used to determine leakage as a function of needle wall thickness, needle taper, injection angle, and wait time from end of injection to withdrawal of needle from skin.

RESULTS

Leakage volume was positively related to injection volume. Injections in the abdomen caused less leakage than thigh injections. A 32G needle caused less leakage than a 31G and a 32G tip (tapered) needle, and a "straight in" 90° needle insertion angle caused less leakage than an angled (~45°) insertion. Wait times of minimum 3 seconds caused less leakage than immediate withdrawal of the needle after injection. Needle wall thickness and injection speed did not influence leakage.

CONCLUSIONS

Leakage will be minimized using a thin needle, using 90° needle insertion in the abdomen, injecting maximum 800 µL at a time, and waiting at least 3 seconds after the injection until the needle is withdrawn from the skin.

Improvement of Insulin Injection Technique: Examination of Current Issues and Recommendations

PURPOSE

Correct insulin injection technique is a crucial aspect of diabetes management. The purpose of this article is (1) to outline the medical literature, including patient-based studies and surveys, surrounding the type of issues and problems that patients encounter with injectable insulin therapy and the degree to which correct insulin technique is being applied and (2) to review the latest recommendations for insulin injection technique and discuss the key aspects that diabetes educators and other health care professionals should be communicating to their patients to ensure that injection technique is optimized.

CONCLUSIONS

Examination of the literature and multiple patient surveys demonstrates that patients continue to have many issues with insulin injection technique, highlighting the pressing need for effective patient education. In addition, many patients are not using insulin pen devices correctly. Widespread lack of injection site rotation and reuse of needles have resulted in high rates of lipohypertrophy. Lipohypertrophy has in turn been associated with significantly increased levels of unexplained hypoglycemia and glycemic variability and significantly increased insulin costs. By providing clear, evidence-based consensus recommendations, initiatives such as the Forum for Injection Technique are helping to address these issues but will be successful only if concerted efforts in patient education and reeducation are made to ensure that these recommendations are implemented consistently. This should involve all stakeholders in insulin therapy-particularly diabetes educators, who are at the forefront of patient education.

Recognition of and steps to mitigate anxiety and fear of pain in injectable diabetes treatment

Injectable treatments, such as glucagon-like peptide-1 receptor agonists and insulin, are options for the pharmacologic treatment of type 2 diabetes. Numerous barriers lead to delay in initiating injectable treatment, which, in turn, may lead to inadequate glycemic control and increased risk of diabetes-related complications, underscoring the need to understand and address these barriers. Barriers to the initiation of injectable therapy, strategies to mitigate barriers, and information about needle attributes and their relation to needle pain are reviewed on the basis of published literature retrieval and our clinical experience. Barriers to the initiation of injectable therapy originate from both patients and practitioners. Anxiety about and fear of injection-associated pain has been estimated to affect approximately 30%-50% of patients before the initiation of diabetes education interventions. Advances in needle design have minimized the pain associated with injections, and recent data suggest that actual pain and bleeding associated with various needle gauges (21-gauge to 31-gauge) are mild. Other barriers include concerns about the ability to handle injectable therapy, concerns about treatment side effects, and impacts on quality of life. Practitioners can help to mitigate barriers to injectable treatment for type 2 diabetes by understanding patient perceptions, improving education, and setting realistic expectations about therapy. Strategies for minimizing injection-associated fear and anxiety include a combination of assessment, appropriate needle selection, patient education, behavioral interventions, and monitoring.

Comparison between shorter straight and thinner microtapered insulin injection needles

BACKGROUND

Many diabetes patients who require insulin perform multiple subcutaneous injections every day that often cause pain, discomfort, and anxiety. We compared efficacy (glycemic control) and patient preference for two types of needle: a shorter straight needle (32 gauge×4 mm, straight wall; Nippon Becton Dickinson Co., Ltd., Tokyo, Japan; hereafter referred to as BD32S4) and a thinner microtapered needle (33-gauge tip and 28-gauge base×5 mm, double-tapered wall; Terumo Corp., Tokyo, Japan; hereafter referred to as TR33T5) in a single-center study.

PATIENTS AND METHODS

Eighty-four patients with diabetes were enrolled in a randomized, open-label crossover trial. The patients injected their usual insulin dosage with one type of needle for 4 weeks and then switched to the other type for the next 4 weeks. The serum glycated albumin level was measured before and after each 4-week period. Each patient assessed pain during injection on a 150-mm visual analog scale (VAS). Needle preference, perceptions of handling, and acceptance were assessed by the patients, who completed a questionnaire after using each type of needle for 4 weeks.

RESULTS

In total, 79 patients completed the study. There was no difference of glycemic control between the two needles. The mean VAS score was -14.5 mm (95% confidence interval, -20.9, -8.0 mm), indicating that the patients perceived less pain with the BD32S4 needle. In the overall evaluation, a significantly higher percentage of patients selected the BD32S4 as the better needle compared with the TR33T5 (60.3% vs. 19.2%; P<0.0001).

CONCLUSIONS

The BD32S4 needle was more highly evaluated and was preferred by the patients with respect to pain during injection, usability, and visual impression, without having a negative impact on glycemic control. The overall preference of patients for the shorter needle in this study suggests that needle length may be one of the major contributing factors for patients' comfort in insulin injection, although the other relevant factors of needles still need to be considered.

Insulin pen needles: effects of extra-thin wall needle technology on preference, confidence, and other patient ratings

BACKGROUND

Pen needles (PNs) are essential for insulin injections using pen devices. PN characteristics affect patients' injection experience.

OBJECTIVE

The goal of this study was to evaluate the impact of a new extra-thin wall (XTW) PN versus usual PNs on overall patient preference, ease of injection, perceived time to complete the full dose, thumb button force to deliver the injection, and dose delivery confidence in individuals with diabetes mellitus (DM). Subjects injected insulin with the KwikPen(TM) (Eli Lilly and Company, Indianapolis, Indiana), SoloSTAR(®) (sanofi-aventis U.S. LLC, Bridgewater, New Jersey), and FlexPen(®) (Novo Nordisk A/S, Bagsvaerd, Denmark) insulin pens, and included some with impaired hand dexterity.

METHODS

We first performed quantitative testing of XTW and comparable PNs with the 3 insulin pens for thumb force, flow rate, and time to deliver medication. A prospective, randomized, 2-period, open-label, crossover trial was then conducted in patients aged 35 to 80 years with type 1 or type 2 DM who injected insulin by pen for ≥2 months, with at least 1 daily dose ≥10 U. Patients who used 4- to 8-mm length PNs with 31- to 32-G diameter were randomly assigned to use their current PN or the same/similar size XTW PN at home for ~1 week and the other PN the second week. They completed several comparative 150-mm visual analog scales and direct questions at the end of period 2.

RESULTS

XTW PNs had statistically significant better performance for each studied PN characteristic (thumb force, flow, and time to deliver medication) for all pens combined and each individual pen brand (all, P ≤ 0.05). Of 216 patients randomized to study groups (80, SoloSTAR; 77, FlexPen; 59, KwikPen), 209 completed both periods; 198 were evaluable. Baseline characteristics revealed a mean (SD) age of 60.8 (9.3) years, insulin pen use duration of 4.3 (4.1) years, and mean total daily dose of 75.1 (52.3) U (range, 10-420 U). Approximately 50% of patients were female; 81.5% were white and 14.8% were black; and 89.8% had type 2 DM. Nearly 99% used a single PN: 8 mm, 49.5%; 5 mm, 24.1%; 6 mm, 14.4%; and 4 mm, 12.0%. Patients rated the XTW PNs (mean [95% CI]) as preferable by a mean of 31.9 mm (27.2-36.6), P < 0.001; XTW PNs required less thumb force, less time to inject the dose, and were rated as providing greater confidence in full dose delivery by 28.4 mm (23.7-33.2), 21.7 mm (17.0-26.4), and 24.4 mm (19.7-29.1), respectively; all, P < 0.001. Results were similar for each of the 3 pens, those with impaired hand dexterity, and for all users of 4-mm PNs. Skin leakage and insulin dripping from the needle tip were rated as less frequent with the XTW PNs (P < 0.05). The most common adverse events were hypoglycemia in 8.3% and 6.0% of patients using XTW PNs and current PNs (P = NS), respectively; hyperglycemia occurred in 2.9% and 4.1% (P = NS). None of the adverse events was serious or considered device related.

CONCLUSIONS

XTW PNs were preferred overall, rated as requiring less time and less thumb force to inject, and providing greater confidence in completing a full dose compared with usual PNs in this group of patients with type 1 or type 2 DM. ClinicalTrials.gov identifier: NCT01852136.

Identification and comparison of insulin pharmacokinetics injected with a new 4-mm needle vs 6- and 8-mm needles accounting for endogenous insulin and C-peptide secretion kinetics in non-diabetic adult males

Aims/Introduction

Many patients with diabetes now use 5‐, 6‐ or 8‐mm needles for insulin injection. However, it is unclear whether needle length, particularly for shorter needles, affects the pharmacokinetic properties of insulin.

Materials and Methods

This was a three‐way, randomized, cross‐over, single‐center study involving 12 healthy Japanese adult males (age 27.4 ± 4.14 years; weight 64.2 ± 5.2 kg; body fat percentage 18.2 ± 1.5%). Participants received a subcutaneous (abdomen) dose of insulin lispro (1.5 U for participants weighing 55 to <65.0 kg; 2.0 U for participants weighing 65.0 to <80.0 kg) delivered using a 32‐G × 4 mm (32G × 4), 31‐G × 8 mm (31G × 8) or 32‐G × 6 mm (32G × 6) needle with a 3–7‐day washout between doses. Pharmacokinetic parameters of exogenous insulin were identified using non‐linear least squares, where the total insulin concentration was fit to the measured plasma insulin concentration using an overall combined model that accounted for C‐peptide/insulin secretion in addition to the injected dose.

Results

Maximum concentration and area under the curve for 0 to infinity min for insulin were bioequivalent for the 32G × 4 needle relative to the 32G × 6 and the 31G × 8 needles. The time to the maximum insulin concentration was bioequivalent for the 32G × 4 needle relative to the 32G × 6 needle, but not the 31G × 8 needle.

Conclusions

The use of 4‐mm needles is unlikely to change the pharmacokinetic properties of insulin when injected subcutaneously in adults. This trial was registered with UMIN‐CTR (no. UMIN000004469).

Empowering people with diabetes: improving perceptions and outcomes with technical advances in insulin pens

For people with diabetes treated with insulin, the development of insulin pens has led to important advantages compared with the use of vials and syringes. Insulin pens are associated with improved ease of use, user confidence, treatment satisfaction, and quality of life compared with vials and syringes. Continual improvements to insulin pen designs to further enhance usability and improve patient perceptions may help to lower patients' resistance to initiating insulin therapy and further improve treatment adherence. This article reviews recent developments in prefilled insulin pens that may assist health care professionals when considering insulin-delivery devices to recommend to their patients.

The role of comfort and discomfort in insulin therapy

Despite the recognized importance of optimal insulin therapy, patient adherence to insulin therapy is an ongoing clinical care challenge. Insulin omission continues to be frequent and underestimated and has been correlated with poorer glycemic control and increased rates of diabetes-related complications. Insulin users consistently identify multiple factors that contribute to insulin injection-related anxiety and to non-adherence. Injection-related discomfort continues to bear a significant contribution. Over the last decade, with advances in needle manufacturing technology, shorter and narrower needles have been associated with progressively improving patient self-rating of injection discomfort. Consequently, patient surveys of insulin users show discomfort to rank in the bottom third of significant contributors by prevalence. However, healthcare providers (HCP) and family member care providers continue to demonstrate a high level of anticipated and perceived pain for the patient. HCP anxiety and pain anticipation are each associated with patient anxiety and may therefore play a significant contributing role in patient non-adherence.

A prefilled insulin pen with a novel injection mechanism and a lower injection force than other prefilled insulin pens

BACKGROUND

FlexTouch(®) (Novo Nordisk A/S, Bagsvaerd, Denmark) is a new prefilled insulin pen for people with diabetes, with a novel injection mechanism and no push-button extension at any dose setting. This study compared the injection force of FlexTouch with that of SoloStar(®) (sanofi-aventis, Paris, France) and KwikPen(®) (Eli Lilly & Co., Indianapolis, IN).

METHODS

Injection force was measured with the manufacturers' recommended needle attached to each pen (NovoFine(®) [Novo Nordisk] 32-gauge tip extra thin wall 6 mm needle for FlexTouch and BD [Franklin Lakes, NJ] MicroFine™ 31-gauge 5 mm needle for SoloStar and KwikPen) during injection of the maximum dose (60 IU for KwikPen and 80 IU for FlexTouch and SoloStar). Injection was performed at three different constant push-button speeds.

RESULTS

FlexTouch had a significantly (P<0.0001) lower injection force than SoloStar and KwikPen at all injection speeds. The mean±SD injection force of FlexTouch was 5.1±0.5 N. At 4, 6, and 8 mm/s push-button speeds, the injection force of SoloStar was 13.5±2.1, 19.1±1.9, and 26.9±2.4 N, respectively, and the injection force of KwikPen was 14.5±1.9, 20.9±1.4, and 28.2±1.4 N, respectively.

CONCLUSIONS

The injection mechanism of FlexTouch means that insulin injection is driven by a torque spring and not the thumb pressure of the user. This results in a 62-82% lower injection force with FlexTouch than other prefilled insulin pens.

What can we learn from patient-reported outcomes of insulin pen devices?

Although a variety of effective treatment options are available for patients with type 1 or type 2 diabetes, many patients in the United States have difficulty reaching their glycemic goals. Patient adherence to insulin therapy, which often involves self-administered subcutaneous injections of insulin using either a vial and syringe or an insulin pen device, is often poor. Various factors associated with the type of injection device have been shown to influence the rate of patient adherence to insulin therapy. This article reviews patient-reported outcome (PRO) evidence from pediatric and adult studies that compared insulin pen devices with vial and syringe use. In a majority of these cases, patients preferred the pen devices over vial and syringe, stating advantages such as ease of use, convenience, greater confidence in their ability to properly administer the drug, and a greater perceived social acceptance. The pens were considered less painful than syringes and were associated with less needle fear. In addition, PRO evidence has directed pen technology design, leading to development of more advanced insulin pen devices. By appreciating the correlation between adherence to insulin regimens and a patient's device preference, clinicians can make improved treatment recommendations to facilitate achievement and maintenance of glycemic targets.

Insulin administration: selecting the appropriate needle and individualizing the injection technique

INTRODUCTION

Patients with diabetes who receive insulin therapy often fail to meet their targets for metabolic control with insulin injections. Their inadequate glycemic control may be related to incorrect injection procedure.

AREAS COVERED

This review examines the latest data related to insulin injection and needle characteristics, which play an integral role in patient satisfaction. Searches of Medline and Cumulative Index to Nursing and Allied Health Literature databases were conducted. Results show that optimal insulin injection can facilitate glycemic control in pediatric and adult patients. In general, needles shorter than 8 mm are appropriate for normal weight, obese pediatric and adult patients. However, body mass index, gender, race, age and injection site can influence the depth of subcutaneous tissue and thus, the desired needle size and injection technique. Although the abdomen, thighs and buttocks are all recommended injection sites, abdominal injections disperse insulin slightly more rapidly than thigh injections.

EXPERT OPINION

Wider acceptance of needles shorter than 6 mm will occur with more evidence of their safety and efficacy, particularly in children. Development of shorter and thinner needles to make injections even easier and less burdensome may be expected in the future.

Needle with a novel attachment versus conventional screw-thread needles: a preference and usability test among adults with diabetes and impaired manual dexterity

BACKGROUND

NovoTwist(®) (Novo Nordisk A/S, Bagsværd, Denmark) is an insulin pen needle that features a novel attachment and detachment system. The aim of this test was to assess overall preference and handling of NovoTwist compared with conventional screw-thread needles in people with type 1 or type 2 diabetes.

METHODS

One hundred twenty adults with type 1 or type 2 diabetes and manual dexterity dysfunction who were currently self-injecting with an insulin pen were included in this open-label, randomized, crossover test. Participants were stratified according to the impact that manual dexterity problems had on their ability to inject insulin (1 = no effect at all; 4 = a lot), and those rated as 1 were excluded from subanalyses because of low numbers. Following instruction, participants attached the needle to Next Generation FlexPen(®) (Novo Nordisk A/S), made an injection into a foam cushion, and detached the needle; this process was repeated three times with NovoTwist and the participant's current screw-thread needle (or NovoFine(®) [Novo Nordisk A/S]) in a random order. Responses to questions on user experience with each needle were subsequently recorded on a 6-point rating scale (1 = very difficult; 6 = very easy).

RESULTS

Significantly more respondents had a preference for NovoTwist (79%) compared with the conventional screw-thread needles (21%, P < 0.001). Significantly more respondents preferred NovoTwist for both ease of attachment (80%, P < 0.001) and ease of detachment (74%, P < 0.001). Most respondents found NovoTwist the most appropriate needle for performing everyday injections (71%, P < 0.001).

CONCLUSIONS

Such preference by patients has a positive impact on the treatment of diabetes as NovoTwist may alleviate the burden of performing everyday injections through its ease of use.

Compatibility testing of two types of pen needles with a range of injection pens for diabetes medication

Compatibility of two types of needles with a variety of durable and prefilled injection pens for diabetes medication was tested by attaching the needles according to ISO 11608-2 and verifying penetration into the cartridge using air shots and two-dimensional X-rays. NovoFine* and NovoFine Autocover† attached correctly to 20 and 19 out of 21 pen types, respectively. Neither needle type attached to Diapen 3.1/3.2, while NovoFine Autocover attached to most, but not all of OptiSet pens.

Comparative glycemic control, safety and patient ratings for a new 4 mm x 32G insulin pen needle in adults with diabetes

OBJECTIVE

Pen needles (PN) for subcutaneous insulin therapy have become smaller; 5 mm PNs are now the shortest in use. We evaluated the safety, efficacy and patient ratings of a new 4 mm x 32 gauge (G) PN.

RESEARCH DESIGN AND METHODS

Subjects with type 1 and type 2 diabetes and HbA1c 5.5% to 9.5% participated in a randomized non-inferiority cross-over trial, at four U.S. centers. Subjects used 4 mm x 32G PNs and either 5 mm x 31G PNs (4/5 mm) or 8 mm x 31G PNs (4/8 mm) in two, 3-week treatment periods; order of needle use was controlled. Subjects were either 'low dose' or 'regular dose' users (highest single insulin dose <or= 20 units and 21-40 units, respectively). Percent absolute change in serum fructosamine (% |Delta Fru|) was the primary endpoint; unexplained, severe hypo- or hyperglycemia was a secondary measure. Leakage at injection sites and pain measured by visual analog scale were tertiary measures. Equivalent glycemic control was defined á priori as % |Delta Fru| (including 95% CI) within 20%; 40 subjects per subgroup provides 90% power at alpha = 0.05.

CLINICAL TRIAL REGISTRATION

The study was registered on clinicaltrials.gov (identifier: NCT00928057).

RESULTS

Of 173 subjects randomized, 168 completed the study, and 163 were included in the fructosamine analyses--83 and 80 in the 4/5 mm and 4/8 mm groups, respectively. Subjects were 56% male, mean 52.6 yrs, 63% type 2. Baseline HbA1c = 7.5 +/- 1.0% and fructosamine 301 +/- 55.1 micromol/L. Mean % |Delta Fru| was 4.9% (95% CI 3.8, 6.0) and 5.5% (4.5, 6.4), respectively, for the 4/5 mm and 4/8 mm groups, meeting glycemic equivalence criteria; results were similar in both dose groups. The median |Delta Fru| was 11.0 micromol/L (8.0, 13.0) and 13.5 micromol/L (9.8, 18.0) for the 4/5 mm and 4/8 mm groups, respectively. Unexplained, severe hypo- and hyperglycemic episodes were infrequent and not different between PNs. The 4 mm PN was rated significantly less painful and preferred by approximately 2/3 of subjects (p < 0.01). All three PNs had similar reported injection site leakage.

LIMITATIONS

The study was of relatively short duration, in adults in the U.S. Further trials in other patients (e.g., GLP-1 users, pediatrics, obese) should be performed.

CONCLUSIONS

The 4 mm x 32G PN provided equivalent glycemic control compared to 31G, 5 mm and 8 mm PNs with reduced pain, no difference in insulin leakage and was preferred by patients.

Insulin pen use for type 2 diabetes--a clinical perspective

While insulin delivery technology continues to progress, its adoption in the clinic lags behind, particularly in people with type 2 diabetes. In this article the authors present their clinical perspective regarding insulin pen therapy in this population.