Intramuscular risk at insulin injection sites--measurement of the distance from skin to muscle and rationale for shorter-length needles for subcutaneous insulin therapy

Modeling drug transport and absorption in subcutaneous injection of monoclonal antibodies: Impact of tissue deformation, devices, and physiology

The pharmaceutical industry has experienced a remarkable increase in the use of subcutaneous injection of monoclonal antibodies (mAbs), attributed mainly to its advantages in reducing healthcare-related costs and enhancing patient compliance. Despite this growth, there is a limited understanding of how tissue mechanics, physiological parameters, and different injection devices and techniques influence the transport and absorption of the drug. In this work, we propose a high-fidelity computational model to study drug transport and absorption during and after subcutaneous injection of mAbs. Our numerical model includes large-deformation mechanics, fluid flow, drug transport, and blood and lymphatic uptake. Through this computational framework, we analyze the tissue material responses, plume dynamics, and drug absorption. We analyze different devices, injection techniques, and physiological parameters such as BMI, flow rate, and injection depth. Finally, we compare our numerical results against the experimental data from the literature.

Addressing Insulin Injection Technique: A Follow-up Study of Canadian Patients with Diabetes

INTRODUCTION

Proper insulin injection technique is important for optimal glycaemic control, yet patients with diabetes often inject insulin incorrectly. Previous studies identified common errors in insulin injection in Canada, and this article seeks to evaluate the current insulin injection technique practices among patients and explore the effectiveness of feedback and education in improving their technique.

METHODS

The study recruited 147 patients and 16 physicians across Canada to gather insights into current insulin injection practices and education gaps. Eligible patients were people living with diabetes who inject insulin using an insulin pen and pen needles. Eligible physicians, who were unsupported by diabetes educators, completed a practice assessment survey and selected 10 eligible patients to complete a baseline assessment survey. During the patient visit, if an error in the patient's technique was identified, a pop-up knowledge transfer (KT) prompt would appear, providing feedback and information on best practices at the point of care. Follow-up surveys were completed 1-3 months later.

RESULTS

Physicians reported facing barriers to providing education and feedback, including lack of time and personnel, and lack of effective educational material. Patients demonstrated modest improvements in some injection technique domains at their follow-up visit, including injection force factors, time the needle was held in the skin, pen needle reuse, injection area size, and injection angle. The most common initial mistakes by patients were selecting an area smaller than recommended and not paying attention to the injection force. At the second visit, patients reduced an average of one error in their injection technique.

CONCLUSION

Results showed that basic feedback by their physician during one visit could exert moderate improvements on patients' injection technique. Proper injection technique is critical for diabetes management, and incorporating targeted ongoing education and support can significantly enhance physician practices, ultimately reducing risks and improving outcomes.

Computational modeling of the effect of skin pinch and stretch on subcutaneous injection of monoclonal antibodies using autoinjector devices

Subcutaneous injection of monoclonal antibodies (mAbs) has experienced unprecedented growth in the pharmaceutical industry due to its benefits in patient compliance and cost-effectiveness. However, the impact of different injection techniques and autoinjector devices on the drug's transport and uptake is poorly understood. Here, we develop a biphasic large-deformation chemomechanical model that accounts for the components of the extracellular matrix that govern solid deformation and fluid flow within the subcutaneous tissue: interstitial fluid, collagen fibers and negatively charged proteoglycan aggregates. We use this model to build a high-fidelity representation of a virtual patient performing a subcutaneous injection of mAbs. We analyze the impact of the pinch and stretch methods on the injection dynamics and the use of different handheld autoinjector devices. The results suggest that autoinjector base plates with a larger device-skin contact area cause significantly lower tissue mechanical stress, fluid pressure and fluid velocity during the injection process. Our simulations indicate that the stretch technique presents a higher risk of intramuscular injection for autoinjectors with a relatively long needle insertion depth.

Ultrasound Detected Subcutaneous Changes in a Pediatric Cohort After Initiation of a New Insulin Pump or Glucose Sensor

Objective: This study examined subcutaneous tissue changes at sites used by continuous subcutaneous insulin infusion (CSII) and continuous glucose monitoring (CGM), and tested whether these changes, if any, were associated with glycated hemoglobin (HbA1c). Research Design and Methods: This prospective study investigated recently used CSII or CGM sites in 161 children and adolescents during the first year after initiation of a new diabetes device. Subcutaneous changes such as echogenicity, vascularization, and the distance from the skin surface to the muscle at CSII and CGM sites were assessed by ultrasound. Results: The distance from skin surface to muscle fascia at both the upper arm and abdomen was influenced by age, body mass index z-score, and sex. Especially in boys and the youngest, the depth of many devices outreached the mean distance. The mean distance for boys at the abdomen and upper arm ranged from 4.5-6.5 mm and 5-6.9 mm for all ages, respectively. Hyperechogenicity at CGM sites was 4.3% after 12 months. The frequency of subcutaneous hyperechogenicity and vascularization at CSII sites increased significantly over time (41.2% to 69.3% and 2% to 16% respectively, P < 0.001 and P = 0.009). Hyperechogenicity in the subcutis was not a predictor of elevated HbA1c (P = 0.11). Conclusion: There is large variation in the distance from the skin surface to the muscle fascia and many diabetes devices reach even deeper. Hyperechogenicity and vascularization increased significantly over time at CSII sites, but not CGM sites. The importance of hyperechogenicity for insulin absorption is unclear and further investigations are needed. Clinical Trial Registration number: NCT04258904.

Investigation of appropriate needle length considering skin thickness with the real injection posture for insulin injections in diabetic patients

BACKGROUND

Insulin treatment is widely used not only for type 1 but also for type 2 diabetes patients. Insulin must be injected into the subcutaneous tissue to be effective. The needle length has been shortened for safety and efficiency. However, whether patients use an appropriate needle length is unclear.

METHODS

Skin thickness was measured by ultrasound with patients in their usual posture during injection. Furthermore, the effect of the intervention in which the needle length was changed was investigated.

RESULTS

Thirty-eight percent of the patients had fluid leakage and injected the needle intradermally. The average skin thickness was 3.3 mm while sitting, which was greater than that in a previous report including measurements taken while lying down. Consequently, the skin thickness was > 4 mm in 9.5% of the patients who used 4-mm needles. Cases of leakage and intradermal injection decreased when the needle length was changed.

CONCLUSIONS

This study identified that the needle length should be considered in patients with thick skin or a lower body mass index due to possibility of intradermal injection.

Motor point heatmap guide for neuromuscular electrical stimulation of the quadriceps muscle

PURPOSE

To create an anatomical chart that indicates the probability of finding a motor point (MP) in different areas of the quadriceps muscle.

METHODS

On 31 healthy adults, the individual anatomy of the vastus medialis (VM), rectus femoris (RF) and vastus lateralis (VL) was determined using ultrasound. Thereafter, a 3 Hz neuromuscular electrical stimulation (NMES) MP-search with a MP-pen was performed. The thigh anatomy was normalized and divided into 112 (8x14) 3x3cm areas, and the probability of finding a MP in the different areas was calculated to create a MP heat-map.

RESULTS

The heat-map displayed the two best 3x3cm areas, over VL and VM respectively, each with a probability greater than 50% of finding a MP and a higher probability compared to all other areas (p <.05). RF exhibited two areas with a 29% probability of finding a MP. A higher number of MPs on the quadriceps, mean (±SD) 9.4 ± 1, was in regression analysis found to be significantly associated with two independent factors higher physical activity level and lower body fat (R² = 0.42, p=<.0001).

CONCLUSION

Large inter-individual variations in location, and number of MPs were found, but the heat-map displayed areas with higher probability of finding a MP and can be used to facilitate NMES-application.

Imaging of large volume subcutaneous deposition using MRI: exploratory clinical study results

Subcutaneous (SC) delivery is a preferred route of administration for biotherapeutics but has predominantly been limited to volumes below 3 mL. With higher volume drug formulations emerging, understanding large volume SC (LVSC) depot localization, dispersion, and impact on the SC environment has become more critical. The aim of this exploratory clinical imaging study was to assess the feasibility of magnetic resonance imaging (MRI) to identify and characterize LVSC injections and their effect on SC tissue as a function of delivery site and volume. Healthy adult subjects received incremental injections of normal saline up to 5 mL total volume in the arm and up to 10 mL in the abdomen and thigh. MRI images were acquired after each incremental SC injection. Post-image analysis was performed to correct imaging artifacts, identify depot tissue location, create 3-dimensional (3D) SC depot rendering, and estimate in vivo bolus volumes and SC tissue distention. LVSC saline depots were readily achieved, imaged using MRI, and quantified via subsequent image reconstructions. Imaging artifacts occurred under some conditions, necessitating corrections applied during image analysis. 3D renderings were created for both the depot alone and in relation to the SC tissue boundaries. LVSC depots remained predominantly within the SC tissue and expanded with increasing injection volume. Depot geometry varied across injection sites and localized physiological structure changes were observed to accommodate LVSC injection volumes. MRI is an effective means to clinically visualize LVSC depots and SC architecture allowing assessment of deposition and dispersion of injected formulations.Trial Registration: Not applicable for this exploratory clinical imaging 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.

Transport and distribution of biotherapeutics in different tissue layers after subcutaneous injection

The subcutaneous injection is the main route of administration for monoclonal antibodies (mAbs) and several other biotherapeutics due to the patient comfort and cost-effectiveness. However, their transport and distribution after subcutaneous injection is poorly understood. Here, we exploit a three-dimensional poroelastic model to find the biomechanical response of the tissue, including interstitial pressure and tissue deformation during the injection. We quantify the drug concentration inside the tissue. We start with a single-layer model of the tissue. We show that during injection, the difference between the permeability of the solvent and solute will result in a higher drug concentration proportional to the inverse permeability ratio. Then we study the role of tissue layered properties with primary layers, including epidermis, dermis, subcutaneous (SQ), and muscle layers, on tissue biomechanical response to injection and drug transport. We show that the drug will distribute mainly in the SQ layer due to its lower elastic moduli. Finally, we study the effect of secondary tissue elements like the deep fascia layer and the network of septa fibers inside the SQ tissue. We use the Voronoi algorithm to create random geometry of the septa network. We show how drugs accumulate around these tissue components as observed in experimental SQ injection. Next, we study the effect of injection rate on drug concentration. We show how higher injection rates will slightly increase the drug concentration around septa fibers. Finally we demonstrate how the concentration dependent viscosity will increase the concentration of biotherapeutics in the direction of septa fibers. .

Repeated insulin injection without site rotation affects skin thickness - ultrasonographic and histological evaluation

AIMS/INTRODUCTION

The influence of repeated insulin injection on subcutaneous tissue is known, but its impact on the skin is unclear. Therefore, this study aimed to elucidate the impact of repeated insulin injections on the skin.

MATERIAL AND METHODS

The properties of the skin and the subcutaneous tissue were evaluated in 52 insulin-treated adult patients with diabetes with abnormal findings at the site of self-injection (36 with subcutaneous nodules, 16 with suspected subcutaneous tissue induration) by ultrasonography. In all subjects, both normal and abnormal areas were examined. In addition, skin biopsies were performed in four subjects.

RESULTS

The skin thickness of the normal and abnormal skin sites was 1.95 (1.60, 2.50) and 2.80 (2.27, 3.30) mm, respectively (median (first quartile, third quartile)), (P < 0.001). The biopsy specimens revealed slightly thickened and tight bundles of collagen in the dermis. Three patients had amyloid deposits in the subcutaneous tissue, and one also showed these in the dermis. These were positively stained for insulin antibody.

CONCLUSIONS

Repeated insulin injection procedures result in skin thickening. Increased collagen fibers and possibly amyloid deposition in the dermis may be involved. The results reaffirmed the importance of appropriate site rotation in insulin injection and revealed the usefulness of ultrasonographic skin examination in evaluating the self-injection procedure.

Insulin induces a progressive increase in the resistance of subcutaneous tissue to fluid flow: Implications for insulin pump therapy

AIM

To determine the effect of insulin on the resistance of subcutaneous tissue to the flow of infusion fluids.

MATERIALS AND METHODS

Thirty subjects with type 1 diabetes wore two Accu-Chek Spirit Combo insulin pumps with Accu-Chek FlexLink infusion sets (Roche Diabetes Care, Mannheim, Germany) for 7 days. One pump was filled with insulin aspart (Novo Nordisk, Bagsvaerd, Denmark) and used for continuous subcutaneous insulin infusion (CSII). The other pump was filled with insulin diluting medium (IDM; Novo Nordisk) and used to deliver IDM subcutaneously at rates identical to those employed for CSII. Both infusion sites were assessed daily by measuring the pressure required to infuse various bolus amounts of IDM.

RESULTS

On day 1, maximum pressure (P_max ) and tissue flow resistance (TFR; calculated from measured pressure profiles) were similar for both infusion sites (P > 0.20). During the subsequent study days, the P_max and TFR values observed at the IDM infusion site remained at levels comparable to those seen on day 1 (P > 0.13). However, at the site of CSII, P_max and TFR progressively increased with CSII duration. By the end of day 7, P_max and TFR reached 25.8 */2.11 kPa (geometric mean */geometric standard deviation) and 8.64 */3.48 kPa*s/μL, respectively, representing a remarkable 3.5- and 20.6-fold increase relative to the respective P_max and TFR values observed on day 1 (P < 0.001).

CONCLUSION

Our results suggest that insulin induces a progressive increase in the resistance of subcutaneous tissue to the introduction of fluid; this has important implications for the future design of insulin pumps and infusion sets.

Leveraging Partnerships to Reduce Insulin Needlestick Injuries: Nurse-Led System-Wide Quality Improvement Project

BACKGROUND

Percutaneous injuries from needlesticks are a major occupational hazard for nurses.

LOCAL PROBLEM

Reducing subcutaneous insulin-related needlestick injuries was part of a nurse-led comprehensive sharps injury-reduction program at an integrated, not-for-profit health system.

METHODS

The incident rate of needlestick injuries was compared between 1 year before and 1 year after introducing this quality improvement project.

INTERVENTIONS

A system-wide educational program instituting changes in subcutaneous insulin administration practices was combined with supply chain standardization using a single type of safety-engineered insulin syringe.

RESULTS

The average monthly incidence of needlestick injuries per 10 000 subcutaneous insulin injections fell significantly from year to year (incidence rate ratio, 0.49; 95% CI, 0.30-0.80; Poisson regression P = .004). One-year cost savings for supplies totaled $3500; additional annual median savings were $24 875 (2019 US dollars) in estimated costs of needlestick injuries averted.

CONCLUSIONS

The effectiveness of this multifaceted project provides a practical template to reduce subcutaneous insulin-related needlestick injuries.

Lipohypertrophy Monitoring Study (LIMO): Effect of single use of 4 mm pen needles combined with education on injection site rotation on glycaemic control: Confirmation of an unpleasant truth

AIMS

To investigate whether single use of 4 mm needles combined with education about injection technique and lipohypertrophy affects HbA1c, hypoglycaemia and glucose variability.

METHODS

Insulin-injecting people with diabetes recruited from nine Belgian diabetes centres were prospectively followed for 6 months. They were provided 4 mm pen needles and education concerning injection technique using an online platform (BD and Me™) based on the international Forum for Injection Technique & Therapy Recommendations focused on avoidance of lipohypertrophy zones and reduction of needle reuse.

RESULTS

A total of 171 people with diabetes were included of which 146 completed the study. At baseline, lipohypertrophy was present in 63.0% of those who completed the study, with 51.4% injecting in zones of lipohypertrophy, 37.0% incorrectly rotating and 95.9% reusing needles. After the intervention, 7.5% still injected in a lipohypertrophy zone, 4.1% rotated incorrectly and needle reuse decreased to 21.2%. The number of participants with severe hypoglycaemias (from 15.8% to 4.1%, p < 0.001), unexplained hypoglycaemias (from 46.6% to 16.4%, p < 0.001) and high glucose variability (from 64.4% to 29.5%, p < 0.001) was significantly reduced. HbA1c and total daily insulin dose remained stable.

CONCLUSION

The combination of 4 mm pen needles and online education on injection techniques significantly reduced the number of people with severe hypoglycaemic episodes, unexplained hypoglycaemia and high glucose variability but did not improve HbA1c control nor lower insulin needs.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04659330.

Abdominal skin subcutaneous fat thickness over the gestational period in Korean pregnant women: a descriptive observational study

Purpose

Although insulin is usually injected into the abdominal subcutaneous fat, in pregnancy women tend to avoid abdominal injections due to concern about fetal damage. Prior studies have been limited to only measuring skin-subcutaneous fat thickness (S-ScFT) at one site at specific pregnancy points. This study aimed to measure S-ScFT across several abdominal sites and over the gestational period in Korean pregnant women. This can identify which site would be relatively safe for subcutaneous injection during pregnancy.

Methods

Healthy women over 24 weeks of pregnancy in Korea were invited to voluntarily participate in this descriptive study. For the 142 women, S-ScFT of 12 sites in the abdomen were measured by ultrasound, several times over the pregnancy. Each incidence was treated as a case and a total of 262 cases were analyzed.

Results

The mean S-ScFT during pregnancy was 1.14±0.47 cm (1.25±0.54 cm at 24⁺⁰–27⁺⁶ weeks; 1.17±0.48 cm at 28⁺⁰–31⁺⁶ weeks; 1.09⁺⁰.40 cm at 32⁺⁰–35⁺⁶ weeks; and 1.06±0.47 cm at 36⁺⁰–40 weeks of pregnancy). Most S-ScFT were thicker than 10 mm. But S-ScFTs in the lateral abdomen and some sites were suboptimal (<6 mm), especially in the pre-pregnancy underweight body mass index group, who had a high rate of suboptimal thickness (27.1% overall and 33.9% in the lateral side).

Conclusion

The whole abdomen seems to be appropriate for subcutaneous injection in most Korean women during pregnancy, with a 4 to 5-mm short needle. However, for the lateral abdomen, making the skin fold might be needed for fetal safety.

Novel cannula design improves large volume auto-injection rates for high viscosity solutions

A prototype reusable large-volume (2 mL) autoinjector (LVAI) was designed to compare injection performance of a novel 27 gauge ultra-thin wall (UTW) pre-filled syringe (PFS) cannula (8 mm external cannula length, 14.4 mm total needle length) against an existing 27 gauge special thin wall (STW) PFS cannula (12.7 mm external cannula length, 19 mm total needle length) across a range of injectate viscosities (2.3–30 cP) in a series of in vivo feasibility studies in swine. The UTW cannula had an approximately 30% greater cross-sectional lumen area than the STW cannula. The target exposed needle length was adjusted to ensure appropriate needle penetration depth and achieve injectate deposition in the subcutaneous (SC) tissue. Delivery time and volume, injection site leakage, injectate depot location, and local tissue effects were examined. The STW and UTW cannulae both provided effective SC delivery of contrast placebo solutions, and were able to accommodate injectate viscosity up to 30 cP without quantifiable leakage from the tissue and with minor tissue effects which resolved within 1–2 hours. Delivery times at each viscosity were significantly different between PFS types with the UTW PFS producing faster delivery times. In a histological substudy of the UTW cannula using injectate viscosities up to 50 cP, injection site reactions were rare and, when present, were of minimal severity. This series of studies demonstrates the feasibility of LVAI SC injection and informs autoinjector and PFS design considerations. Use of a UTW cannula may enable more rapid LVAI injections with minimal tissue effects, especially for higher viscosity formulations.

Transport and lymphatic uptake of monoclonal antibodies after subcutaneous injection

The subcutaneous injection has emerged to become a feasible self-administration practice for biotherapeutics due to the patient comfort and cost-effectiveness. However, the available knowledge about transport and absorption of these agents after subcutaneous injection is limited. Here, a mathematical framework to study the subcutaneous drug delivery of mAbs from injection to lymphatic uptake is presented. A three-dimensional poroelastic model is exploited to find the biomechanical response of the tissue by taking into account tissue deformation during the injection. The results show that including tissue deformability noticeably changes tissue poromechanical response due to the significant dependence of interstitial pressure on the tissue deformation. Moreover, the importance of the amount of lymph fluid at the injection site and the injection rate on the drug uptake to lymphatic capillaries is highlighted. Finally, variability of lymphatic uptake due to uncertainty in parameters including tissue poromechanical and lymphatic absorption parameters is evaluated. It is found that interstitial pressure due to injection is the major contributing factor in short-term lymphatic absorption, while the amount of lymph fluid at the site of injection determines the long-term absorption of the drug. Finally, it is shown that the lymphatic uptake results are consistent with experimental data available in the literature.

User experiences with second-generation 32-gauge × 4 mm vs. thinner comparator pen needles: prospective randomized trial

OBJECTIVE

Two similarly designed studies compared user experiences with a second-generation extra-thin-wall, 5-bevel 32 G × 4 mm pen needle (PN) with redesigned hub versus four thinner commercially available PNs.

METHODS

Adults (18-75 years old) with type 1 or type 2 diabetes and ≥3 months of experience with pen injectors qualified for single-visit, single-blinded randomized studies. The investigational 32 G PN was compared with three 33-34 G × 3.5-4 mm PNs in Study 1 and one 34 G × 4 mm PN in Study 2. Participants completed 12 abdominal injections of 0.3 mL sterile saline using insulin pens in 6 pairs, each comprising one investigational 32 G PN and one comparator PN in random order. After each injection pair, participants compared injection pain via relative 150 mm visual analog scale (VAS) and perceived dose delivery force via relative 5 point Likert scale. Adjusted models tested injection pain scores (primary endpoint) for noninferiority and, if met, then for superiority. ClinicalTrials.gov identifiers: NCT03878758 and NCT03878745.

RESULTS

The investigational 32 G PN met noninferiority as well as superiority criteria for less injection pain vs. each comparator (p < .01), with adjusted mean relative VAS scores 9.1-17.6 in Study 1 (n = 154) and 7.3 in Study 2 (n = 55). The investigational 32 G PN was also superior vs. each comparator PN in requiring less relative perceived force to deliver the dose (p < .01).

CONCLUSIONS

The investigational 32 G PN was associated with less participant-reported injection pain and less perceived dose delivery force compared with four thinner PNs, suggesting no additional pain reduction or force reduction benefit conferred by the thinner PNs.

Performance characterization of spring actuated autoinjector devices for Emgality and Aimovig

Objective: Autoinjectors are a convenient and efficient way to self-administer subcutaneous injections of biopharmaceuticals. Differences in device mechanical design can affect the autoinjector functionality and performance. This study investigates the performance differences of two single-spring-actuated autoinjectors.Methods: We compare the performance between Emgality (120 mg/mL) and Aimovig (140 mg/mL) autoinjector devices from an engineering point of view at two test conditions: room (25 C[Formula: see text]) and storage (5 C[Formula: see text]) temperatures. We employ a novel experimental procedure to simultaneously acquire the force and acoustic signals during operation, and high-speed imaging during the needle insertion and drug injection.Results: We perform 18 quantitative comparisons between Emgality and Aimovig, and we observe that 14 of these have statistically significant differences. For both test conditions, Emgality requires an 8 N activation force while Aimovig requires 14 N activation force, and the needle of Emgality has an insertion depth of 5 mm while Aimovig has an insertion depth of 7 mm. The injection speeds are significantly affected by temperature. Emgality has an injection speed of 0.40 mL/s and 0.28 mL/s at room and storage temperature condition, respectively; while Aimovig has an injection speed of 0.24 mL/s and 0.16 mL/s at those conditions. Lastly, confirmation "click" sound of Emgality occurs 0.75-1.53 s after dose completion, while in Aimovig, the confirmation "click" sound occurs 0.26-0.46 s before dose completion.Conclusions: This study revealed performance differences between Emgality and Aimovig autoinjector devices, despite the fact that the delivery principle of these single-spring-actuated autoinjectors are the same. These differences may result in different risk of intramuscular injection and premature device removal, both of which need to be further verified in clinical trials.

User experience for manual injection of 2 mL viscous solutions is enhanced by a new prefillable syringe with a staked 8 mm ultra-thin wall needle

OBJECTIVES

User experience was compared between a new pre-fillable 2.25 mL glass syringe equipped with an ultra-thin-wall (UTW) 8 mm staked needle and a marketed BD Neopak™ syringe equipped with a special-thin-wall (STW) 12.7 mm staked needle.

METHODS

Participants simulated subcutaneous injections with both syringes alone (formative Human Factors study) and in combination with a needlestick-prevention device (validation Human Factors study).

RESULTS

Usability results of both studies showed higher success rates for delivering the full dose of 2 mL viscous solution (30 cP) with the 8mmUTW syringe than with the 12.7mmSTW one (63% vs. 42% in the formative study). The use of the 8mmUTW syringe demonstrated also better ease of use and acceptance results and 72% of formative study participants preferred this new syringe over the current one when delivering the viscous solution. Using a shorter needle also showed a benefit in decreasing the injection-related anxiety. Besides, in the case of a non-recommended injection technique, the calculated risk of accidental intramuscular injection is reduced by 2 to 13 times with the 8mmUTW syringe.

CONCLUSION

Altogether, the results obtained demonstrated an improvement of the user experience with this new syringe compared to the current one in the manual delivery of 2 mL viscous solutions.

Evaluation of Antidiabetic Injectable Technique: Is There an Association between Accuracy and Health Literacy or Duration of Diabetes?

Introduction:

Effective diabetes pharmacotherapy often involves injectable medications, which if used inappropriately represents a type of unintentional medication nonadherence that leads to poor outcomes.

Objectives:

The primary objective of this study was to assess the percent of patients who accurately prepared, administered, stored, and disposed of their injectable diabetes medication. Secondary objectives included comparing the accuracy of injectable use among those with diabetes <5 years vs. ≥ 5 years duration and those with limited vs. proficient health literacy.

Methods:

This was a prospective analysis conducted on a convenience sample of patients who received a pilot pharmacist-led, quality improvement service at an urban, ambulatory care clinic. The service components included health literacy screening, using the Rapid Assessment of Adult Literacy in Medicine – Short Form (REALM-SF) tool, evaluation of injectable technique by use of a standardized questionnaire, and provision of medication education. Duration of diabetes was determined by patient self-report. Chi-square and Fisher’s exact tests were utilized to assess accuracy of injectable technique in two group comparisons: (1) patients with limited vs. proficient health literacy and (2) patients with diabetes <5 years vs. ≥5 years.

Results:

Thirty-five patients were included in the analysis. Despite the majority (71.4%) of patients reporting prior education on injectable use, 54.3% reported at least one error in product use. Significant findings noted were that those with limited health literacy had higher rates of accurately using the skin-fold technique and appropriate angle for injection vs. those with proficient health literacy (p<0.05 for both comparisons). Likewise, more patients in the cohort of diabetes duration ≥5 years accurately rotated the injection site vs. those with a duration <5 years (p=0.001).

Conclusion:

Errors in injectable technique were common in this study and spanned across health literacy levels and duration of diabetes. Patients prescribed injectable diabetes medications should be routinely educated on proper technique for use.

Improved insulin injection technique, treatment satisfaction and glycemic control: Results from a large cohort education study

•

The efficacy of insulin therapy in diabetes depends on proper injection technique.

•

Professional education can results in higher patients’ satisfaction.

•

Proper insulin injection is important to good glycemic control.

Objective

The aim of this study was to elucidate injection techniques, treatment satisfaction and glycemic control after education among patients with type 2 diabetes.

Methods

4513 insulin-treated diabetic patients enrolled in the observational study EGIDA II (Education and GensuPen In Diabetology II) filled out the questionnaire which focused on key insulin injection parameters, pain sensation scale and satisfaction of the treatment form before (visit 1) and after 3 months treatment with insulin injection (visit 2). The education was performed by trained healthcare professionals. To assess the utility and comfort during using new automatic injection system (GensuPen) we separated 2 groups: A – treated with GensuPen and B – treated with other pens.

Results

The education resulted in increased number of patients who properly remix cloudy insulin; inject insulin into skin; change every time the injection site; use the pen needle only once; prepare a pen for injection and store insulin. We noticed significant decrease in BMI and sensation of pain in both groups. Our study revealed that patients’ satisfaction with the treatment increased with each of the 5 items (type of the treatment, mood, physical activity, vital energy, a sense of control over the disease) using a 5-point scale, with greater increase in group A. The utility and comfort (weight, thickness, easiness in remove pen cap, cleaning, twisting, keeping in hand the pen, dial the dose, readable signaling of injected dose) during using the GensuPen significantly increased in group A. Finally the mean glucose level in self-control diary was significantly lower after 3 months of the treatment in both groups, however the difference between visit 1 and 2 was greater in group A.

Conclusion

The study showed that proper selection of pen and professional education can result in the improvement of insulin injection technique, higher patients’ satisfaction and better glycemic control.

Prevalence, Risk Factors, and Clinical Characteristics of Lipodystrophy in Insulin-Treated Patients with Diabetes: An Old Problem in a New Era of Modern Insulin

BACKGROUND

Lipodystrophy has been reported as a common complication in insulin-treated patients, which could lead to unexplained hypoglycemia and suboptimal glycemic control. This study aimed to determine the prevalence, associated risk factors, and clinical characteristics of insulin-induced lipodystrophy in Thai patients.

PATIENTS AND METHODS

This was a cross-sectional study involving insulin-treated patients at Theptarin Hospital, one of the largest diabetes centers in Thailand.

RESULTS

A total of 400 patients were studied (female 53.5%, T2DM 86%, mean age 65.6±15.4 years, duration of diabetes 23.0±10.2 years, median insulin treatment 10 years, usage of insulin analog 72.1%, A1C 7.9±1.6%) . The prevalence of lipohypertrophy (LH) in overall patients was 37.3% (T1DM 46.4% and T2DM 35.8%). The highest prevalence (57.5%) was observed in long-standing (≥10 years) T1DM patients. Multivariate analysis revealed that the duration of insulin use (≥10 years), use of human insulin, and incorrect rotation of injection sites were associated with LH. Patients with LH were found to have 7-times greater risk of unexplained hypoglycemia when compared with patients without LH. Lipoatrophy (LA) was found in only four cases (1.0%). All LA cases had a concurrence palpable area of LH.

CONCLUSION

Insulin-induced lipodystrophy is still an overlooked complication in the conundrum of diabetes care. The presence of lipodystrophy was significantly associated with the occurrence of unexplained hypoglycemia. It should be emphasized to recognize this condition by inspecting and palpating insulin injecting sites regularly, and educate patients to avoid the development of lipodystrophy.

Insulin-induced lypodistrophy in hemodialyzed patients: A new challenge for nephrologists?

Diabetes Mellitus (DM) is the most common cause of renal failure and ESRD all over the world, and often requires an individualized insulin treatment regimen. Malnutrition, depression-related eating behavior changes, high on-off-dialysis day-to-day glycemic variability and frequent hypoglycemic events occurring during or immediately after dialysis make it hard to identify best insulin dosage in hemodialyzed patients. This suggests a prudent attitude including non-stringent control, despite which repeated hypoglycemia quite often occurs in such patients. When looking for possible sources of hypoglycemia, health professionals too often overlook the identification of skin lipodystrophy (LD) due to an incorrect insulin injection technique. This mini-review focuses on the high frequency (57%) of LD in a cohort of 1004 insulin-treated people with DM on dialysis consecutively referring to our joint medical centers, and on its relationship with hypoglycemia and glycemic control/variability. When taking on such patients, care team members accept to face a complex disease burdened with several risk factors requiring high professional skills, and have to keep in mind also the possible presence of any LD areas eventually interfering with expected results. A timely educational intervention on the correct injection technique can help reduce the high risk of hypoglycemia and large glycemic variability in dialysed people with DM.

Subcutaneous Injection of Drugs: Literature Review of Factors Influencing Pain Sensation at the Injection Site

The subcutaneous administration route is widely used to administer different types of drugs given its high bioavailability and rapid onset of action. However, the sensation of pain at the injection site might reduce patient adherence. Apart from a direct effect of the drug itself, several factors can influence the sensation of pain: needle features, injection site, volume injected, injection speed, osmolality, viscosity and pH of formulation, as well as the kind of excipients employed, including buffers and preservatives. Short and thin needles, conveniently lubricated and with sharp tips, are generally used to minimize pain, although the anatomic injection site (abdomen versus thigh) also affects the sensation of pain. Large subcutaneous injection volumes are associated with pain. In this sense, the maximum volume generally accepted is around 1.5 ml, although volumes of up to 3 ml are well tolerated when injected in the abdomen. Injected volumes of up to 0.5–0.8 ml are not expected to increase substantially the pain produced by the needle insertion. Ideally, injectable products should be formulated as isotonic solutions (osmolality of about 300 mOsm/kg) and no more than 600 mOs/kg have to be used in order to prevent pain. A pH close to the physiological one is recommended to minimize pain, irritation, and tissue damage. Buffers are frequently added to parenteral formulations to optimize solubility and stability by adjusting the pH; however, their strength should be kept as low as possible to avoid pain upon injection. The data available recommend the concentration of phosphate buffer be limited to 10 mM and that the concentration of citrate buffer should be lower than 7.3 mM to avoid an increased sensation of pain. In the case of preservatives, which are required in multiple-dose preparations, m-cresol seems to be more painful than benzyl alcohol and phenol.

Funding: Sandoz SA.

The Injection Technique Factor: What You Don't Know or Teach Can Make a Difference

IN BRIEF To be consistently effective, insulin must be delivered into subcutaneous tissue. If insulin is delivered intramuscularly, its uptake and action become variably faster, leading to suboptimal, inconsistent glucose control. The best strategy to avoid intramuscular injection is to use the shortest needles available. Injection sites should be rotated systematically to prevent lipohypertrophy, which also substantially affects insulin uptake and action. New evidence-based insulin delivery recommendations are available, and awareness of them should lead to more effective use of insulin therapy, improved clinical outcomes, and considerable cost savings.

Evaluating the Impact of Human Factors and Pen Needle Design on Insulin Pen Injection

BACKGROUND

Limited published data exists quantifying the influence of human factors (HF) and pen needle (PN) design on delivery outcomes of pen injection systems. This preclinical in vivo study examines the impact of PN hub design and applied force against the skin during injection on needle penetration depth (NPD).

METHOD

To precisely locate injection depth, PN injections (20 µl; 2 IU, U-100 volume equivalent) of iodinated contrast agent were administered to the flank of Yorkshire swine across a range of clinically relevant application forces against the skin (0.25, 0.75, 1.25, and 2.0 lbf). The NPD, representing in vivo needle tip depth in SC tissue, from four 32 G × 4 mm PN devices (BD Nano^™ 2nd Gen and three commercial posted-hub PN devices; n = 75/device/force, 1200 total) was measured by fluoroscopic imaging of the resulting depot.

RESULTS

The reengineered hub design more closely achieved the 4 mm target NPD with significantly less variability ( P = .006) than commercial posted-hub PN devices across the range of applied injection forces. Calculations of IM (intramuscular) injection risk completed through in silico probability model, using NPD and average human tissue thickness measurements, displayed a commensurate reduction (~2-8x) compared to conventional PN hub designs.

CONCLUSIONS

Quantifiable differences in injection depth were observed between identical labeled length PN devices indicating that hub design features, coupled with aspects of variable injection technique, may influence injection depth accuracy and consistency. The reengineered hub design may reduce the impact of unintended individual technique differences by improving target injection depth consistency and reducing IM injection potential.

EADSG Guidelines: Insulin Storage and Optimisation of Injection Technique in Diabetes Management

To date, insulin therapy remains the cornerstone of diabetes management; but the art of injecting insulin is still poorly understood in many health facilities. To address this gap, the Forum for Injection Technique and Therapy Expert Recommendations (FITTER) published recommendations on injection technique after a workshop held in Rome, Italy in 2015. These recommendations are generally applicable to the majority of patients on insulin therapy, athough they do not explore alternative details that may be suitable for low- and middle-income countries. The East Africa Diabetes Study Group sought to address this gap, and furthermore to seek consensus on some of the contextual issues pertaining to insulin therapy within the East African region, specifically focusing on scarcity of resources and its adverse effect on the quality of care. A meeting of health care professionals, experts in diabetes management and patients using insulin, was convened in Kigali, Rwanda on 11 March 2018, and the following recommendations were made: (1) insulin should be transported safely, without undue shaking and exposure to high (> 32 °C) temperature environments. (2) Insulin should not be transported below 0 °C. (3) If insulin is to be stored at home for over 2 months, it should be stored at the recommended temperature of 2-8 °C. (4) Appropriate instructions should be given to patients while dispensing insulin. (5) Insulin in use should be kept at room temperature and should never be kept immersed under water. Immersing insulin under water after the vial has been pierced carries a high risk of contamination, leading to loss of potency and likelihood of causing injection abscesses. (6) The shortest available needles (4 mm for pen and 6 mm for insulin syringe) should be preferred for all patients. (7) In routine care, intramuscular injections should be avoided, especially with long-acting insulins, as it may result in severe hypoglycaemia. (8) The practice of slanting the needle excessively should be avoided as it results in sub-epidermal injection of insulin which leads to poor absorption and may cause "tattooing" of the skin and scarring. (9) In patients presenting in a wasted state, with "paper-like skin", injections should, if possible, be initiated with pen injection devices, so as to utilise the 4-mm needle without lifting a skin fold (pinching the skin); otherwise lifting of a skin fold is required, if longer needles are utilised. (10) Reuse of needles and syringes is not recommended. However, as the reuse of syringes and needles is practiced for various reasons, and by many patients, individuals should not be given alarming messages; and usage should be limited to discarding when injections become more painful; but at any rate not to exceed reusing a needle more than 5 times.

Similar Pharmacokinetics of the Adalimumab (Humira®) Biosimilar BI 695501 Whether Administered via Subcutaneous Autoinjector or Prefilled Syringe (VOLTAIRE®-AI and VOLTAIRE®-TAI): Phase 1, Randomized, Open-Label, Parallel-Group Trials

INTRODUCTION

BI 695501 has shown similar efficacy, safety, and immunogenicity to the adalimumab reference product, Humira®. We present two phase 1 studies comparing the pharmacokinetics, safety, and immunogenicity of BI 695501 delivered via autoinjector (AI) vs. prefilled syringe (PFS).

METHODS

Both trials were randomized, open-label, parallel-group studies undertaken in subjects aged ≥ 18-65 years. VOLTAIRE®-AI (NCT02606903) recruited healthy, Caucasian, male, non-athletic volunteers with BMI ≥ 18 to ≤ 30 kg/m2. VOLTAIRE®-TAI (NCT02899338) recruited healthy men and women with BMI > 17.5 to < 35 kg/m2. In both studies, a single dose of BI 695501 40 mg was administered via AI or PFS to the abdomen (VOLTAIRE®-AI) or thigh (VOLTAIRE®-TAI). The observation period was 43/57 days and the safety follow-up was 70 days. Co-primary endpoints were AUC0-1032 or AUC0-1368, Cmax, and AUC0-∞. Safety and immunogenicity were assessed.

RESULTS

Subjects (VOLTAIRE®-AI: N = 71; VOLTAIRE®-TAI: N = 162) were randomized to AI (n = 35; n = 81) or PFS (n = 36; n = 81). Baseline characteristics were balanced between treatment groups in each study. Total exposure of BI 695501 was similar for both groups; adjusted geometric mean ratios for AUC0-∞, AUC0-1032, and Cmax were 106.17, 104.09, and 114.83%, respectively, for VOLTAIRE®-AI; 103.19, 101.71 (AUC0-1368), and 100.11% for VOLTAIRE®-TAI. In both studies, similar immunogenicity was observed between groups in terms of frequency of binding and neutralizing anti-drug antibody-positive subjects. Incidence of adverse events was similar for both groups.

CONCLUSIONS

Pharmacokinetics and immunogenicity of BI 695501 delivered via AI were similar to administration using a PFS, independent of injection site. No differences are expected between AI and PFS use in clinical practice.

FUNDING

Boehringer Ingelheim.

Insulin Injection Technique in China Compared with the Rest of the World

INTRODUCTION

Approximately 9 million people in China use insulin but little is known of their injection techniques (IT). Our aim was to understand IT in China via direct examination and a detailed survey.

METHODS

Injection Technique Questionnaire (ITQ) results of 3853 patients from 20 representative centers in China were compared with the Rest of World (ROW).

RESULTS

Insulin pens are used by 92% of Chinese insulin injectors, with > 3/4 using 4- or 5-mm pen needles. This is consistent with Chinese BMI values (and thus subcutaneous fat thickness) being lower than in ROW, raising the risk of IM (intramuscular) injections with longer needles. Total daily insulin dose is ~ 33 IU in China vs. 45 IU elsewhere. Lipohypertrophy (LH) rates are lower than in ROW, but still found in at least 25% of Chinese patients. Patients apparently do not realize they have LH or are unaware of the hazards of injecting into LH since many of them do so, and those who do use a mean of 11 IU more of insulin than non-LH patients. This incremental insulin use possibly costs the Chinese health care service around 2 billion RMB annually. Needle reuse is also frequent in China (78% vs. 48% ROW), and the high cost of pen needles is the main reason patients cite for reusing (25% use a single needle > 10×).

CONCLUSION

This study reveals many areas in which Chinese professionals and patients can optimize injection practices and thereby improve outcomes and reduce costs. The official guidelines of the Chinese Diabetes Society, based on the FITTER recommendations, offer a roadmap for reaching this goal.

FUNDING

BD Diabetes Care. Plain language summary available for this article.

Turkish Insulin Injection Technique Study: Population Characteristics of Turkish Patients with Diabetes Who Inject Insulin and Details of Their Injection Practices as Assessed by Survey Questionnaire

INTRODUCTION

Over 7 million people in Turkey have diabetes. Of the 1 million who inject insulin little is known of their habits and injection techniques.

METHODS

We conducted an Injection Technique Questionnaire (ITQ) survey throughout Turkey that involved 1376 patients from 56 centers. Turkish values were compared with those from 41 other countries participating in the ITQ, known here as Rest of World (ROW).

RESULTS

The majority (50.4%) of Turkish insulin users give four injections/ day as opposed to ROW, where only 30.9% do. The abdomen is the most common injection site used by Turkish patients, but they also inject insulin in multiple body sites more often than do patients in ROW. Body mass index values in Turkey were 0.75 units higher than those in ROW as was the mean total daily dose (average daily dose [ADD]) of insulin (54.0 IU in Turkey vs. 47.4 IU in ROW). Mean glycated hemoglobin (HbA1c) in Turkey was 9.1%, which is higher than in ROW and possibly related to the higher BMI and ADD. Turkish patients use insulin analogs (short and long-acting) more frequently than do patients in ROW. The shortest pen needles (4 mm) are used by about one-third of patients in Turkey, but the longer ones (8 mm) are equally common. Needles are reused in Turkey at a rate of 3.4 injections/single needle. However, needle reuse, whether with pens or syringes, is lower in Turkey than ROW, as is the number of times a reused needle is used. More than 75% of used sharps in Turkey go into the rubbish, with nearly 6% having no protection of the tip.

CONCLUSION

The continued use of 8-mm needles raises the risk of intramuscular injections in Turkish patients. Despite full reimbursement, needle reuse still remains an important issue. More focus needs to be given to dwell times under the skin, reconstitution of cloudy insulant, correct use of skin folds and safe disposal of sharps.

FUNDING

BD Diabetes Care.

Optimizing insulin delivery for patients with diabetes

Management of diabetes for residents in long-term care settings is particularly challenging, due to the wide range of physical and mental limitations that bear on efficacy of their medications, as well as practical issues associated with the optimal administration of these medications. Foremost among the practical issues for residents requiring insulin injections, is the need to ensure that it is consistently delivered to the circulation at the target rate and dosage, thereby avoiding life-threatening episodes of hypoglycemia. Recent evidence from a multinational survey has elucidated principles of insulin injection technique, including optimal needle length and site rotation that can greatly improve consistency in delivering insulin to the subcutaneous compartment, while reducing pain, improving patient compliance, and limiting the total daily dosage. The present review consolidates these findings and highlights the most critical take-home messages for healthcare professionals working in this area.

Ultrasound-guided measurement of skin and subcutaneous tissue thickness in children with diabetes and recommendations for giving insulin injections

Aim

To measure skin thickness (ST) and skin + subcutaneous layer thickness (SCT) by ultrasound and estimate the risk of intramuscular injection (IM) with different needle lengths across injection sites according to age group.

Method

Children recruited between 1 and 18 years with type 1 and 2 diabetes on insulin injections and divided into three age groups: 1–6 years, 7–12 years and 13–18 years. A portable ultrasound was used to measure ST and SCT at four injection sites on the abdomen, arm, thigh and buttock.

Results

Total 153 children enrolled for the study. The mean (SD) measurement of ST & SCT at four sites on abdomen, arm, thigh & buttocks were as follows; 4.33 mm (±2.22), 5.55 mm (±2.26), 5.83 mm (±3.12), 6.48 mm (±3.47) in 1–6 years old; 7.11 mm (±3.68), 7.79 mm (±4.54), 7.17 mm (±3.62), 8.51 mm (±3.65) in 7–12 years old; 8.94 mm (±4.50), 8.42 mm (±5.00), 8.61 mm (±4.76), 9.76 mm (±4.38) in 13–18 years old. Young children, 1–6 years have the highest risk of IM injection with all needle lengths, i.e. 4, 5, 6, 8 & 12.7 mm, while older children 7–12 & 13–18 years have a lower risk with shorter needles (4, 5 and 6 mm) as compared to longer needles (8 and 12.7 mm).

Conclusions

Children with diabetes on insulin therapy should be advised on the appropriate needle length accordingly to their age and BMI.

Insulin Injection Technique Questionnaire: results of an international study comparing Brazil, Latin America and World data

BACKGROUND

In 2014-2015, the largest international survey of insulin injection technique in patients with diabetes taking insulin was conducted in 42 countries, totaling 13,289 participants. In Brazil, patients from five public health centers were included. This study aims to evaluate insulin injection technique in Brazilian patients and compare results with Latin America (LatAm) and World data.

METHODS

The insulin Injection Technique Questionnaire (ITQ) survey consisted of an initial patient section (questions applied by an experienced nurse), followed by observation of injection technique and examination of the injection sites by the health care professional.

RESULTS

In Brazil, 255 patients were evaluated: 25% had type 1 diabetes mellitus (T1DM) and 75% had T2DM. In this study, 79% of patients injected less than 4 times a day, and 17.3% used insulin pens, compared to 28% in LatAm and 86% worldwide. Syringes were used by 78% of patients in Brazil, compared to 65% in LatAm and 10% globally. Differences in needle length were substantial-nearly 64% in Brazil inject with 8 mm length needle compared to 48% in LatAm and 27% worldwide. Additionally, 48% of patients in Brazil skip doses, 80% reuse pen needles and 57% reuse syringes with 27% having lipohypertrophy by exam.

CONCLUSION

Brazilian patients use syringes more and pens less, inject with larger needles and have more lipohypertrophy when compared to Latin America and World data. Their re-use of needles and syringes is also high. This study showed that in Brazil, teaching of proper injection technique has to be more widespread, and more intensive during diabetes educational sessions, and the type of delivered supplies must be updated to smaller, shorter needles preferred by patients, in order to facilitate adherence to treatment. From the ITQ, we conclude that there are many aspects of insulin injection technique that may be improved in Brazil.

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.

A Randomized Controlled Trial to Assess the Impact of Proper Insulin Injection Technique Training on Glycemic Control

INTRODUCTION

Improper injection technique can negatively affect glycemic control and treatment tolerability. We assessed the impact of structured insulin injection training on glycemic control.

METHODS

We compared changes in glycated hemoglobin (A1C) and fasting plasma glucose following structured insulin injection training in a 6-month pilot study in patients with type 1 or 2 diabetes. Patients were recruited from mobile clinics in Moscow, Russia, and randomized into three groups. Groups 1 and 2 received structured injection training, and group 3 did not. Group 1 received 4-mm needles sufficient for each injection; groups 2 and 3 provided their own needle supply. Changes in insulin total daily dose (TDD), injection technique, needle reuse, and lipohypertrophy (LH) were assessed.

RESULTS

Of 120 patients enrolled, 116 were included in all analyses (group 1, n = 43; group 2, n = 35; group 3, n = 38). At 6 months, mean [95% CI] reductions in A1C were significant in groups 1 and 2 (- 1.00% [10.9 mmol/mol (- 1.3 to - 0.6)] and - 1.00% [10.9 mmol/mol (- 1.4 to - 0.7)], respectively; P < 0.001 for both), but not in group 3 (- 0.02% [0.2 mmol/mol (- 1.2 to 1.6)]). Increases in insulin TDD, however, were similar and significant across groups (approximately 6 IU; P < 0.05). Injection technique improved, and needle reuse and LH declined in groups 1 and 2, but not in group 3.

CONCLUSIONS

Little is known about the glycemic impact of insulin injection training. We found that structured training and the use of short pen needles can improve injection technique, leading to significant A1C reductions and decreased rates of LH.

An Effective Intervention for Diabetic Lipohypertrophy: Results of a Randomized, Controlled, Prospective Multicenter Study in France

BACKGROUND

Lipohypertrophy (LH) is highly prevalent and is potentially harmful to insulin-injecting patients.

METHODS

In this study, we assessed the impact of injection technique (IT) education, including use of a 4-mm pen needle on insulin-treated patients with clinically observed LH in a randomized, controlled, prospective multicenter study in France with follow-up of 6 months. Intensive education and between-visit reinforcement were given to the intervention group. Control patients received similar messages at study outset.

RESULTS

A total of 123 patients were recruited (age 52.1 ± 15.7 years; men 70.7%; body mass index >30 kg/m²: 34.2%; type 1: 53.7%; years with diabetes mellitus: 18.1 ± 10.5), of which 109 patients were included in the final analysis. The intervention group (n = 53) showed a significant decrease of total daily dose of insulin (average at baseline: 54.1 IU) at 3 months (T-3) and 6 months (T-6), reaching just over 5 IU versus baseline (P = 0.035). Corresponding, although not significant, decreases occurred in controls (n = 56); between-group differences were not significant. There were significant decreases in HbA1c (up to 0.5%) at T-3 and T-6 in both groups, with no significant differences between groups. A significant number of intervention patients improved their IT habits; about half achieved ideal IT habits by T-3 versus a quarter of control patients. By T-6, 2/3 of intervention patients achieved either ideal or acceptable IT habits, while only 1/3 of control patients did.

CONCLUSIONS

Our intervention was effective in both study arms, however, to a greater degree and more rapidly in the intervention group. Widespread application of this intervention could be highly cost-effective.

Forum for Injection Technique and Therapy Expert Recommendations, India: The Indian Recommendations for Best Practice in Insulin Injection Technique, 2017

Health-care professionals in India frequently manage injection or infusion therapies in persons with diabetes (PWD). Patients taking insulin should know the importance of proper needle size, correct injection process, complication avoidance, and all other aspects of injection technique from the first visit onward. To assist health-care practitioners in their clinical practice, Forum for Injection Technique and Therapy Expert Recommendations, India, has updated the practical advice and made it more comprehensive evidence-based best practice information. Adherence to these updated recommendations, learning, and translating them into clinical practice should lead to effective therapies, improved outcomes, and lower costs for PWD.

Indian Injection Technique Study: Population Characteristics and Injection Practices

INTRODUCTION

It was estimated that 3.2 million Indians with diabetes injected insulin in 2010, but little is known about the techniques used.

METHODS

In 2015 we conducted an injection technique questionnaire (ITQ) survey throughout India involving 1011 patients. Indian values were compared with those from 41 other countries participating in the ITQ, known here as rest of world (ROW).

RESULTS

Mean HbA1c was 8.6. BMI values in India were 1.5-3 units lower than in ROW depending on patient group, meaning the risk of intramuscular (IM) injections is high in India. The mean total daily dose (TDD) of insulin was lower in every category of Indian patient than in ROW, perhaps reflecting the lower BMI. Needle reuse, whether with pens or syringes, is much higher in India than ROW and so is the number of times the needle is used. The majority (56.8%) of Indian insulin users performed only 2 injections/day as opposed to ROW where 45% of patients performed at least 4 injections/day. Indian patients inject insulin in the thighs more often than patients in ROW, a site where IM injections are more risky. Many patients do not have proper access to sharps containers or have other risk factors that could lead to blood-borne pathogen spread. More than 60% of used sharps in India go into the rubbish, with nearly 12% not even having the minimum protection of a cap.

DISCUSSION

The shortest needles are very common in India; however, the level of needle reuse is high. Multiple daily injections therapy is not as common in India as ROW. More focus needs to be given to dwell times under the skin, reconstitution of cloudy insulins, skinfolds, and safe sharps disposal.

Exercise management in type 1 diabetes: a consensus statement

Type 1 diabetes is a challenging condition to manage for various physiological and behavioural reasons. Regular exercise is important, but management of different forms of physical activity is particularly difficult for both the individual with type 1 diabetes and the health-care provider. People with type 1 diabetes tend to be at least as inactive as the general population, with a large percentage of individuals not maintaining a healthy body mass nor achieving the minimum amount of moderate to vigorous aerobic activity per week. Regular exercise can improve health and wellbeing, and can help individuals to achieve their target lipid profile, body composition, and fitness and glycaemic goals. However, several additional barriers to exercise can exist for a person with diabetes, including fear of hypoglycaemia, loss of glycaemic control, and inadequate knowledge around exercise management. This Review provides an up-to-date consensus on exercise management for individuals with type 1 diabetes who exercise regularly, including glucose targets for safe and effective exercise, and nutritional and insulin dose adjustments to protect against exercise-related glucose excursions.

UK lipohypertrophy interventional study

INTRODUCTION

Lipohypertrophy (LH) is one of the most common complications of insulin therapy. We conducted a prospective study in 18 UK centres to assess the impact of a targeted LH intervention on a range of clinical, biological and socio-economic parameters.

METHODS

Seventy-five insulin-injecting patients were recruited randomly and were followed prospectively for 3-6months, with results compared to baseline values. Interventions included the use of an intensive education program and a switch to a 4mm pen needle.

RESULTS

At all injection sites LH decreased significantly by the end of the study, either disappearing completely or shrinking by approximately 50% from its original diameter. Injections into LH decreased by more than 75% by the end. Most patients were not correctly rotating injection sites at the beginning but by the end most were, by a 5-fold margin. Only 1/3 of our subjects used the 4mm needle at the beginning of the study, however, virtually all did by study end. The mean HbA1c improved by more than 4mmol/L and there were significantly lower levels of unexpected hypoglycaemia and glucose variability. Total daily doses of insulin dropped by an average of 5.6 IU by study end.

CONCLUSIONS

We believe the impressive clinical improvements seen with training to prevent LH can be achieved by wide adoption of the interventions outlined in this study.

Efficacy of a Novel Prefilled, Single-Use, Needle-Free Device (Zeneo®) in Achieving Intramuscular Agent Delivery: An Observational Study

BACKGROUND

It is recognized that, as a result of variation in tissue anatomy, current auto-injectors may have insufficient needle length to achieve successful intramuscular agent delivery in a number of patients. The Zeneo^® auto-injector is a novel prefilled, single-use, needle-free device currently in development for intradermal, subcutaneous, and intramuscular agent delivery across a variety of clinical indications. We aimed to evaluate delivery depth of the device calibrated at pressure appropriate for intramuscular (IM) administration.

METHODS

This was a prospective single-center study in healthy adult volunteers, in whom each received a single injection of saline into the anterolateral thigh. Using sequential MRI scans, we measured skin-to-muscle distance (STMD) agent delivery depth, and the success of IM agent penetration. Device dynamic pressure measurements were also recorded.

RESULTS

Results are reported for 37 subjects with evaluable MRI scans; 19 men, 18 women; mean age 38 years (range 20-58); mean BMI 27.0 kg/m² (range 21.2-30.8 kg/m²). Mean STMD values were 18.6 mm (range 13.4-23.6 mm) in women and 10.0 mm (range 5.0-21.7 mm) in men, with gender differences due primarily to greater subcutaneous thickness in women. A trend for greater STMD in subjects with BMI greater than 25 kg/m² was seen. Mean injectate penetration depths of 30.1 mm (range 20.2-45.6 mm) were observed with values similar in male and female subjects. Successful IM delivery was reported in 95% of subjects. When failure occurred, this was not due to inadequate injection depth. Device pressure (P _max) had the greatest influence on injectate muscle penetration.

CONCLUSION

Use of the Zeneo^® auto-injector achieves delivery depth that ensures intramuscular delivery in both men and women, regardless of BMI. Consistent with other reported data, STMD is greater in women.

FUNDING

Crossject.

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.

Worldwide Injection Technique Questionnaire Study: Population Parameters and Injection Practices

From February 1, 2014, through June 30, 2015, 13,289 insulin-injecting patients from 423 centers in 42 countries took part in one of the largest surveys ever performed in diabetes. The goal was to assess patient characteristics, as well as historical and practical aspects of their injection technique. Results show that 4- and 8-mm needle lengths are each used by nearly 30% of patients and 5- and 6-mm needles each by approximately 20%. Higher consumption of insulin (as measured by total daily dose) is associated with having lipohypertrophy (LH), injecting into LH, leakage from the injection site, and failing to reconstitute cloudy insulin. Glycated hemoglobin values are, on average, 0.5% higher in patients with LH and are significantly higher with incorrect rotation of sites and with needle reuse. Glycated hemoglobin values are lower in patients who distribute their injections over larger injection areas and whose sites are inspected routinely. The frequencies of unexpected hypoglycemia and glucose variability are significantly higher in those with LH, those injecting into LH, those who incorrectly rotate sites, and those who reuse needles. Needles associated with diabetes treatment are the most commonly used medical sharps in the world. However, correct disposal of sharps after use is critically suboptimal. Many used sharps end up in public trash and constitute a major accidental needlestick risk. Use of these data should stimulate renewed interest in and commitment to optimizing injection practices in patients with diabetes.

Can the upper inner side of the thigh become a new option for insulin injection?

OBJECTIVE

Sites for subcutaneous insulin injections include the upper arms, abdomen, buttocks and outer sides of the thigh. No similar study has explored the feasibility of using the inner side of the thigh for insulin injection, since the 4 mm pen needles were introduced for clinical use. This study aimed to determine whether the inner side of the thigh is suitable for insulin injection.

RESEARCH DESIGN AND METHODS

Seventy-five patients with diabetes under insulin therapy from the Inpatient Department of Endocrinology were recruited for this non-blinded, non-randomized observational study. Subcutaneous adipose layer thicknesses of the upper, middle and lower area of the inner and outer thighs of 35 patients were measured by ultrasound, distance from the skin surface to the femoral deep vessels in 20 patients was measured, and insulin was injected at the upper inner and outer sides of the thigh in 20 patients. Pain perception, bleeding or bruising, leakage at the injection sites, blood glucose changes after insulin injection, and preferred ratings of the patients were measured.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT02307968.

RESULTS

Subcutaneous adipose layer thicknesses at both the upper inner and outer thighs were more than 4 mm and the minimum distance was 10 mm. Among the 100 injections at the upper inner thigh, only three incidents of perceived pain occurred. No bleeding or bruising and leakage were observed from the inner or outer sides. Furthermore, the difference in blood glucose control between insulin injections at the inner side and outer sides was not statistically significant. Patient ratings for injections at the inner side were similar to injections at the outer side. The key limitation of this study was the small sample size of adult patients as well as the non-randomized controlled design of this study.

CONCLUSION

The upper inner thigh might be a new option for insulin injection rotation.

Safety and efficacy of insulin therapy delivered via a 4mm pen needle in obese patients with diabetes

OBJECTIVE

To determine whether insulin delivered via a 4-mm × 32-gauge pen needle (PN) provides equivalent glycemic control as 8-mm × 31-gauge and 12.7-mm × 29-gauge PNs in obese (body mass index ≥30) patients with diabetes.

PATIENTS AND METHODS

This prospective, multicenter, randomized, open-label, 2-period, crossover, equivalence, home-based study was conducted from October 26, 2010, through May 31, 2012. After a 3-week wash-in period, eligible patients aged 18 to 80 years with a hemoglobin A1c (HbA1c) level of 5.5% to 9.5% (37-80 mmol/mol) were randomized to compare either 4- vs 8-mm PNs or 4- vs 12.7-mm PNs, using each of the 2 assigned PNs for 12 weeks in random order. The primary outcome was change in HbA1c level, with equivalence limits of ±0.4%.

RESULTS

The 274 patients randomized (mean ± SD age, 56.7±11.0 years) had a mean ± SD body mass index of 37.0±6.1 (range, 29.1-59.9) and took up to 350 U of insulin daily; 226 patients were included in the modified intention-to-treat analysis. Mean (95% CI) changes in HbA1c levels with the 4-mm PN were -0.08% (-0.21 to 0.06) and -0.10% (-0.19 to 0.00) vs the 8- and 12.7-mm PNs, respectively, within equivalence margins. The 4-mm PN was less painful than the larger PNs (P<.05), with similar leakage rates reported (4.1%-4.3%). Patients preferred the 4-mm PN over the 12.7-mm PN (P<.05) but not significantly vs the 8-mm PN. There were no differences between PNs in insulin doses and hypoglycemic or hyperglycemic adverse event rates.

CONCLUSION

The 4-mm × 32-gauge PN provides equivalent glycemic control as 8- and 12.7-mm PNs in obese patients with diabetes, with less pain and no increase in leakage. Shorter PNs should be considered in all insulin-requiring patients with diabetes, including those who are obese.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01231984.