- Email: [email protected]
Pen Needle Preference in a Population of Canadians with Diabetes: Results from a Recent Patient Survey
Can J Diabetes xxx (2015) 1e4
Contents lists available at ScienceDirect
Canadian Journal of Diabetes journal homepage: www.canadianjournalofdiabetes.com
Original Research
Pen Needle Preference in a Population of Canadians with Diabetes: Results from a Recent Patient Survey Lori Berard RN, CDE *, Brett Cameron BSc, Vincent Woo MD, FRCPC Winnipeg Regional Health Authority, Health Sciences Centre, Winnipeg Diabetes Research Group, Department of Medicine, Section of Endocrinology, University of Manitoba, Winnipeg, Manitoba, Canada
a r t i c l e i n f o
a b s t r a c t
Article history: Received 20 June 2014 Received in revised form 29 September 2014 Accepted 29 September 2014 Available online xxx
Objective: To evaluate the safety and efficacy of insulin injections in patients using 8 mm 31 gauge vs. 5 mm 31 gauge pen needles, as determined by A1C results and to measure individual patient satisfaction and compare overall satisfaction regarding the use of the 2 needles. Methods: The study was completed as a substudy of a single-site, open-label, randomized, 6-month comparative study consisting of 66 obese patients. Prior to the study, all individuals had treated their diabetes with either long-acting insulin glargine or insulin detemir. At the onset of the study, patients were randomized 1:1 to either insulin glargine or neutral protamine Hagedorn insulin. All patients used an 8 mm pen needle for the first 3 months and a 5 mm pen needle for the remaining 3 months. At the conclusion of the trial, patients completed a questionnaire regarding pen needle satisfaction. Results: The 5 mm needle was preferred by 41.8% of study subjects, while the 8 mm needle was preferred by 27.9% of subjects. For other attributes (i.e. overall injection comfort, pain when inserting the needle into the skin and length of needle), the 5 mm needle scored higher than the 8 mm needle and higher also than the percentage of individuals who indicated no preference. Conclusions: In patients with insulin-treated type 2 diabetes with a mean single-injection volume dose of basal insulin of 50.2 units, the 5 mm needle was generally preferred over the 8 mm needle. The shorter needle was more comfortable and easier to use while being equally effective in delivering insulin. Ó 2015 Canadian Diabetes Association
Keywords: diabetes education insulin patient satisfaction pen needles
r é s u m é Mots clés : enseignement sur le diabète insuline satisfaction des patients aiguilles pour stylo
Objectif : D’après les résultats de l’A1c, évaluer l’innocuité et l’efficacité des injections d’insuline chez les patients utilisant des aiguilles pour stylo de 8 mm à pointe de calibre 31 par rapport aux aiguilles pour stylo de 5 mm à pointe de calibre 31, puis mesurer la satisfaction personnelle des patients et comparer la satisfaction globale concernant l’utilisation des 2 aiguilles. Méthodes : L’étude était réalisée en tant que sous-étude d’un seul site, une étude comparative de 6 mois, ouverte et à répartition aléatoire, consistant en 66 patients obèses. Avant l’étude, tous les individus avaient traité leur diabète soit par insuline glargine ou par insuline détémir à action prolongée. Au début de l’étude, les patients étaient répartis de manière aléatoire selon un ratio 1:1, soit ceux traités par insuline glargine ou ceux traités par insuline NPH (Neutral Protamin Hagedorn). Tous les patients utilisaient une aiguille pour stylo de 8 mm au cours des 3 premiers mois et une aiguille pour stylo de 5 mm au cours des 3 mois restants. À la fin de l’étude, les patients remplissaient un questionnaire évaluant leur satisfaction à propos des aiguilles pour stylo. Résultats : Quarante et un et huit dixièmes pour cent (41,8 %) des sujets de l’étude préféraient l’aiguille de 5 mm, tandis que 27,9 % des sujets préféraient l’aiguille de 8 mm. Pour ce qui est des autres caractéristiques (c.-à-d. le confort global lors de l’injection, la douleur pendant l’insertion de l’aiguille dans la peau et la longueur de l’aiguille), l’aiguille de 5 mm a obtenu un score plus élevé que celui de l’aiguille de 8 mm, ainsi qu’un score plus élevé que le pourcentage des individus qui n’indiquaient aucune préférence. Conclusions : Les patients diabétiques de type 2 traités par insuline selon une dose moyenne d’insuline basale en injection unique de 50,2 unités préféraient généralement l’aiguille de 5 mm à l’aiguille de 8
* Address for correspondence: Lori Berard, RN, CDE, Winnipeg Regional Health Authority, Health Sciences Centre Winnipeg, Diabetes Research Group, University of Manitoba, 838-715 McDermot Avenue, Winnipeg, Manitoba R3E 3P4, Canada. E-mail address: [email protected] 1499-2671/$ e see front matter Ó 2015 Canadian Diabetes Association http://dx.doi.org/10.1016/j.jcjd.2014.09.008
2
L. Berard et al. / Can J Diabetes xxx (2015) 1e4
mm. L’aiguille la plus courte offrait un meilleur confort lors de l’injection et était plus facile à utiliser, tout en offrant la même efficacité d’administration d’insuline. Ó 2015 Canadian Diabetes Association
Introduction Despite advances in needle technology, there has been some hesitance among diabetes healthcare professionals and patients alike regarding the use of shorter needles. In a 2009 publication regarding diabetes products, the Canadian Diabetes Association (1) recommended that people who are obese or who require large doses of insulin should not use shorter pen needles. The following study was completed in 2010, at which time the standard needle lengths were 8 mm, 12 mm and 12.7 mm. Shorter and finer insulin pen needles (i.e. 5 mm and 6 mm long) had recently been introduced to the diabetes market. Today, even shorter 4 mm pen needles are available and suitable for use by all patients (2). This study was undertaken to counter the popular belief amongst healthcare providers that longer needles are more effective than shorter, finer needles. The study seeks to show that shorter, finer needles could in fact be safe and effective and perhaps improve injection quality for people with diabetes. Recent studies have shown that regardless of age, sex and weight, skin thickness varies minimally among individuals, and the average skin thickness at injection sites is between 0.9 mm and 2.4 mm (3,4). Thus, shorter needles are long enough to penetrate through the skin and reach the subcutaneous tissue in order to administer insulin in the proper area. Moreover, a number of studies have demonstrated that shorter needles (i.e. 5 mm or 6 mm) are equally effective in maintaining glycemic control as longer needles (i.e. 8 mm or 12.7 mm) (5e8). Shorter needles have also been associated with reduced pain, no difference in insulin leakage (5,8) and improved patient satisfaction (5,6). Methods Study design and sample population In conjunction with a substudy of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, an investigatorinitiated single-site study was performed to compare 8 mm 31 gauge pen needles to 5 mm 31 gauge pen needles in an openlabel nonrandomized design. The aim of the study was to determine the appropriate needle length for insulin injection in obese people with diabetes. The trial evaluated the safety and efficacy of treatment, as determined by glycated hemoglobin (A1C) results. Individual satisfaction as well as overall satisfaction regarding the use of both needles was measured and compared. Procedures and instruments All patients participating in the 6-month trial used an 8 mm pen needle for the first 3 months and a 5 mm pen needle for the remaining 3 months. The needles used were exactly the same, save for the difference in length. Subjects did not receive any additional counselling on injection technique at this time. At the conclusion of the trial, patients completed a questionnaire regarding pen-needle satisfaction. The questionnaire consisted of 3 parts: 8 mm penneedle satisfaction, 5 mm pen-needle satisfaction and a comparative section. The questionnaire scored items on a scale from “not at all satisfied” to “extremely satisfied.” The questionnaire also contained open-ended questions, allowing participants to state their thoughts regarding needle satisfaction. Information regarding
weight, A1C and fasting plasma glucose was obtained from the switch trial.
Statistical analysis Analysis of covariance, with treatment as a fixed effect and baseline value for the variable being analyzed, was used to analyze changes from baseline for the secondary variables.
Results Demographics The baseline, midpoint and endpoint clinical characteristics of the study group are presented in Table 1. As noted, the patients in the trial experienced no significant changes in weight, A1C or fasting plasma glucose.
Insulin dosage Subjects entered into the main trial on either basal insulin alone or basal bolus. For the purpose of this article, we concentrated on basal insulin-dose volume. At study entry, single-injection volumes of basal insulin ranged from 7 to 150 units, with a mean of 50.2 units. Data obtained at the end of the trial for largest singledose volume from the subjects indicated that 18.0% of subjects’ largest doses were between 1 and 20 units of insulin; 24.6% were between 21 and 40 units; 21.3% were between 41 and 60 units; and 36.1% were more than 60 units. In the study population, the highest proportion of patients had a single-injection insulin dose above 60 units.
Preferred pen attributes Data for the preferred pen attributes are presented in Table 2. Patients were asked to indicate their preferred pen needle for the attributes listed. If the participants found no difference between needles, the “no preference” option was selected. The 5 mm needle was preferred by 41.8% of study subjects, whereas the 8 mm needle was preferred by 27.9% of subjects. For other attributes (i.e. overall injection comfort, pain when inserting the needle into the skin and length of needle), the 5 mm needle scored higher than the 8 mm needle and also higher than the percentage of individuals who indicated no preference. Furthermore, when excluding individuals who had no preference for each attribute listed, the highest percentage of patients still preferred the 5 mm pen needle.
Table 1 Study population (n¼66)* Characteristic
Baseline
Month 3
Month 6
Weight (kg) A1C (%) FPG (mmol/L)
101.419.8 8.11.2 8.02.3
102.920.4 8.01.03 8.22.4
102.620.6 7.91.0 7.32.0
A1C, Glycated hemoglobin; FPG, fasting plasma glucose; kg, kilograms; SD, standard deviation. * Data given as mean SD.
L. Berard et al. / Can J Diabetes xxx (2015) 1e4 Table 2 Preferred pen attributes
3
Table 4 5 mm and 8 mm needle attribute scores
Variable
5 mm 8 mm No needle (%) needle (%) preference (%)
Characteristic
5 mm needle
8 mm needle
Preferred pen needle Overall injection comfort Quality from needle to needle Ease of inserting needle into skin Ease of putting needle onto the pen Least pain when inserting needle into the skin Least pain when delivering the insulin Gauge of needle Needle length
41.8 48.8 35.0 40.0 30.5 44.4
27.9 26.8 15.0 16.4 11.9 13.0
30.3 24.4 50.0 43.6 57.6 42.6
37.3 38.2 40.0
20.3 14.5 28.0
42.4 47.3 32.0
Injection comfort Needle quality Ease of inserting needle into skin Ease of putting needle on the pen Least pain when inserting needle into the skin Least pain when delivering insulin Needle gauge Needle length Overall satisfaction
4.10.8 4.20.7 4.20.7 4.30.8 4.30.9 4.21.0 4.30.9 4.01.3 3.91.1
3.71.2 4.01.0 3.91.1 4.30.8 / / 3.91.0 3.61.4 3.80.9
Injection-related issues Questions regarding injection-related issues are shown in Table 3. Each patient answered 3 questions regarding both the 5 and 8 mm pen needles. Data derived from responses indicate that the majority of individuals, whether they were delivering insulin with the 5 or 8 mm pen needle, experienced few issues with insulin delivery. Needle breakage during insulin delivery was the least frequent issue noted in both the 5 and 8 mm groups (1.9% and 3.3%, respectively). The largest discrepancy in results between the treatment groups was associated with insulin leakage at the injection site: while using the 5 mm pen needle, only 33.9% of individuals experienced leakage, whereas 41.0% using the 8 mm needle experienced leakage.
5 mm and 8 mm needle attribute scores Attribute scores for the 5 and 8 mm needles are shown in Table 4. Subjects completed a questionnaire regarding needle characteristics specific to either the 5 mm or the 8 mm pen needle. Individuals rated the needle attributes using a Likert scale, whereby “not at all satisfied” scored 1 point, while “extremely satisfied” scored 5 points. The majority of the 8 mm pen needle scores were in the upper range of the category “somewhat satisfied.” The 5 mm pen needle attribute scores were in the lower range of the “very satisfied” category.
Discussion In this study, the authors compared the effects of insulin administration between an 8 mm pen needle, and a 5 mm pen needle. The study consisted of obese individuals with poorly controlled diabetes, the majority of whom were injecting >40 units in a single dose, with a significant percentage delivering >60 units in a single injection. Based on common beliefs, it would be assumed that this study group would require, and indeed prefer, a longer pen
Table 3 Injection-related questions Variable Did you notice any insulin leakage at the injection site? Yes, n (%) No, n (%) Did you notice any bending of the needle? Yes, n (%) No, n (%) Did the needle break during injection? Yes, n (%) No, n (%)
5 mm needle
8 mm needle
19 (33.9) 37 (66.1)
25 (41.0) 36 (59.0)
9 (15.5) 48 (84.5)
12 (19.7) 49 (80.3)
1 (1.9) 52 (98.1)
2 (3.3) 59 (96.7)
needle. However, our study showed that individuals preferred the shorter pen needle. The attribute scores from the questionnaires revealed that the majority of patients experienced either no difference in pain or less pain when using shorter needles. Study subjects also found shorter needles to be the least painful upon insertion and delivery of insulin. In our study, the 5 and 8 mm pen needles used by the patients had identical features, including needle gauge (i.e. 31 gauge). Previous studies have shown that a larger needle diameter is associated with a greater frequency of painful injections (9). Because all needle characteristics were the same in this study, it can be inferred that the differences in pain reported were associated with needle length. Despite the higher doses of insulin used, there was no observed difference in insulin leakage between groups. This finding is supported by information gathered from a recent study that assessed the effectiveness of the 5 mm pen needle (10), and it found minimal leakage associated with the 5 mm pen needle in insulin doses up to 60 units. The 5 and 8 mm pen needles were equally effective in maintaining glycemic control. During both the first half of the study (when the 8 mm pen needle was used) and the second half of the study (when the 5 mm pen needle was used), both groups experienced a similar decrease in A1C. Based on the attribute scores, the 5 mm pen needle was preferred over the 8 mm pen needle. For each attribute compared, subjects revealed either greater or equivalent satisfaction with the 5 mm pen needle. The data obtained revealed a significant difference between groups with respect to injection comfort and ease of inserting the needle into skin. However, comparison of the overall preference category scores showed little difference between groups. In a similar study, which compared 6 mm needles (31 gauge) with 12.7 mm needles (29 gauge) in obese individuals, 89% of study subjects preferred the shorter needle (6). Study limitations included an open-label nonrandomized design starting all subjects at 8 mm pens for 3 months followed by 5 mm pens for 3 months. Unfortunately, this flawed method resulted from a late initiative to attempt to trial 5 mm needles in this population. The late addition to this trial of the ongoing protocol led to the questionnaires’ all being completed after 5 mm use. It is interesting to note that many subjects had not even detected a change in needle length. It is also important to note that we were able to determine the safety and efficacy in maintaining glycemic control with use of the shorter, finer needle, addressing the hesitation of healthcare providers. Conclusions The study revealed that in insulin-treated patients with type 2 diabetes using a mean single-injection volume of 50.2 units of basal insulin, the 5 mm needle was generally preferred to the 8 mm
4
L. Berard et al. / Can J Diabetes xxx (2015) 1e4
needle. The shorter needle was more comfortable and easier to use, while being equally effective in delivering insulin, as determined by A1C levels. Moreover, there were fewer reports of insulin leakage with the 5 mm needle, compared with the 8 mm needle. Author Disclosures Lori Berard is a paid consultant for BD Canada. No funding was received by the authors to create, deliver, analyze or report this survey. BD Canada supported the research through provision of free pen needles. Author Contributions Lori Berard and Brett Cameron contributed substantially to the design and analysis of the data and drafted the article. Vincent Woo contributed substantially to the design and analysis of the data and reviewed the article for intellectual content. References 1. Canadian Diabetes Association. 2009e10 Guide to Diabetes Products and Diabetes Medications. Toronto: Canadian Diabetes Association. Accessed, www. diabetes.ca.
2. Berard L, Desrochers F, Husband A, et al. FIT Forum for Injection Technique Canada: Recommendations for Best Practice in Injection Technique. http:// www.bd.com/resource.aspx?IDX¼25063. Accessed May 13, 2014. 3. Gibney MA, Arce CH, Byron KJ, Hirsch LJ. Skin and subcutaneous adipose layer thickness in adults with diabetes at sites used for insulin injections: Implications for needle length recommendation. Curr Med Res Opin 2010;26: 1519e30. 4. Laurent A, Mistretta F, Bottigioli D, et al. Echographic measurement of skin thickness in adults by high-frequency ultrasound to assess the appropriate microneedle length for intradermal delivery of vaccines. Vaccine 2007;25: 6423e30. 5. Hirsch LJ, Gibney MA, Albanese J, et al. Comparative glycemic control, safety and patient ratings for a new 4 mm 32 G insulin pen needle in adults with diabetes. Curr Med Res Opin 2010;26:1531e41. 6. Schwartz S, Hassman D, Shelmet J, et al. A multicenter, open-label, randomized, two-period crossover trial comparing glycemic control, satisfaction, and preference achieved with a 31 gauge 6 mm needle versus a 29 gauge 12.7 mm needle in obese patients with diabetes mellitus. Clin Ther 2004;26:1663e78. 7. Strauss K, Hannet I, McGonigle J, et al. Ultra-short (5 mm) insulin needles: Trial results and clinical recommendations. Pract Diabetes Int 1999;16:218e22. 8. G1 Kreugel, Keers JC, Kerstens MN, Wolffenbuttel BH. Randomized trial on the influence of the length of two insulin pen needles on glycemic control and patient preference in obese patients with diabetes. Diabetes Technol Ther 2011;13:737e41. 9. Arendt-Nielsen L, Egekvist H, Bjerring P. Pain following controlled cutaneous insertion of needles with different diameters. Somatosens Mot Res 2006;23: 37e43. 10. Hofman PL, Derraik JG, Pinto TE, et al. Defining the ideal injection techniques when using 5-mm needles in children and adults. Diabetes Care 2010;33: 1940e4.
Contents lists available at ScienceDirect
Canadian Journal of Diabetes journal homepage: www.canadianjournalofdiabetes.com
Original Research
Pen Needle Preference in a Population of Canadians with Diabetes: Results from a Recent Patient Survey Lori Berard RN, CDE *, Brett Cameron BSc, Vincent Woo MD, FRCPC Winnipeg Regional Health Authority, Health Sciences Centre, Winnipeg Diabetes Research Group, Department of Medicine, Section of Endocrinology, University of Manitoba, Winnipeg, Manitoba, Canada
a r t i c l e i n f o
a b s t r a c t
Article history: Received 20 June 2014 Received in revised form 29 September 2014 Accepted 29 September 2014 Available online xxx
Objective: To evaluate the safety and efficacy of insulin injections in patients using 8 mm 31 gauge vs. 5 mm 31 gauge pen needles, as determined by A1C results and to measure individual patient satisfaction and compare overall satisfaction regarding the use of the 2 needles. Methods: The study was completed as a substudy of a single-site, open-label, randomized, 6-month comparative study consisting of 66 obese patients. Prior to the study, all individuals had treated their diabetes with either long-acting insulin glargine or insulin detemir. At the onset of the study, patients were randomized 1:1 to either insulin glargine or neutral protamine Hagedorn insulin. All patients used an 8 mm pen needle for the first 3 months and a 5 mm pen needle for the remaining 3 months. At the conclusion of the trial, patients completed a questionnaire regarding pen needle satisfaction. Results: The 5 mm needle was preferred by 41.8% of study subjects, while the 8 mm needle was preferred by 27.9% of subjects. For other attributes (i.e. overall injection comfort, pain when inserting the needle into the skin and length of needle), the 5 mm needle scored higher than the 8 mm needle and higher also than the percentage of individuals who indicated no preference. Conclusions: In patients with insulin-treated type 2 diabetes with a mean single-injection volume dose of basal insulin of 50.2 units, the 5 mm needle was generally preferred over the 8 mm needle. The shorter needle was more comfortable and easier to use while being equally effective in delivering insulin. Ó 2015 Canadian Diabetes Association
Keywords: diabetes education insulin patient satisfaction pen needles
r é s u m é Mots clés : enseignement sur le diabète insuline satisfaction des patients aiguilles pour stylo
Objectif : D’après les résultats de l’A1c, évaluer l’innocuité et l’efficacité des injections d’insuline chez les patients utilisant des aiguilles pour stylo de 8 mm à pointe de calibre 31 par rapport aux aiguilles pour stylo de 5 mm à pointe de calibre 31, puis mesurer la satisfaction personnelle des patients et comparer la satisfaction globale concernant l’utilisation des 2 aiguilles. Méthodes : L’étude était réalisée en tant que sous-étude d’un seul site, une étude comparative de 6 mois, ouverte et à répartition aléatoire, consistant en 66 patients obèses. Avant l’étude, tous les individus avaient traité leur diabète soit par insuline glargine ou par insuline détémir à action prolongée. Au début de l’étude, les patients étaient répartis de manière aléatoire selon un ratio 1:1, soit ceux traités par insuline glargine ou ceux traités par insuline NPH (Neutral Protamin Hagedorn). Tous les patients utilisaient une aiguille pour stylo de 8 mm au cours des 3 premiers mois et une aiguille pour stylo de 5 mm au cours des 3 mois restants. À la fin de l’étude, les patients remplissaient un questionnaire évaluant leur satisfaction à propos des aiguilles pour stylo. Résultats : Quarante et un et huit dixièmes pour cent (41,8 %) des sujets de l’étude préféraient l’aiguille de 5 mm, tandis que 27,9 % des sujets préféraient l’aiguille de 8 mm. Pour ce qui est des autres caractéristiques (c.-à-d. le confort global lors de l’injection, la douleur pendant l’insertion de l’aiguille dans la peau et la longueur de l’aiguille), l’aiguille de 5 mm a obtenu un score plus élevé que celui de l’aiguille de 8 mm, ainsi qu’un score plus élevé que le pourcentage des individus qui n’indiquaient aucune préférence. Conclusions : Les patients diabétiques de type 2 traités par insuline selon une dose moyenne d’insuline basale en injection unique de 50,2 unités préféraient généralement l’aiguille de 5 mm à l’aiguille de 8
* Address for correspondence: Lori Berard, RN, CDE, Winnipeg Regional Health Authority, Health Sciences Centre Winnipeg, Diabetes Research Group, University of Manitoba, 838-715 McDermot Avenue, Winnipeg, Manitoba R3E 3P4, Canada. E-mail address: [email protected] 1499-2671/$ e see front matter Ó 2015 Canadian Diabetes Association http://dx.doi.org/10.1016/j.jcjd.2014.09.008
2
L. Berard et al. / Can J Diabetes xxx (2015) 1e4
mm. L’aiguille la plus courte offrait un meilleur confort lors de l’injection et était plus facile à utiliser, tout en offrant la même efficacité d’administration d’insuline. Ó 2015 Canadian Diabetes Association
Introduction Despite advances in needle technology, there has been some hesitance among diabetes healthcare professionals and patients alike regarding the use of shorter needles. In a 2009 publication regarding diabetes products, the Canadian Diabetes Association (1) recommended that people who are obese or who require large doses of insulin should not use shorter pen needles. The following study was completed in 2010, at which time the standard needle lengths were 8 mm, 12 mm and 12.7 mm. Shorter and finer insulin pen needles (i.e. 5 mm and 6 mm long) had recently been introduced to the diabetes market. Today, even shorter 4 mm pen needles are available and suitable for use by all patients (2). This study was undertaken to counter the popular belief amongst healthcare providers that longer needles are more effective than shorter, finer needles. The study seeks to show that shorter, finer needles could in fact be safe and effective and perhaps improve injection quality for people with diabetes. Recent studies have shown that regardless of age, sex and weight, skin thickness varies minimally among individuals, and the average skin thickness at injection sites is between 0.9 mm and 2.4 mm (3,4). Thus, shorter needles are long enough to penetrate through the skin and reach the subcutaneous tissue in order to administer insulin in the proper area. Moreover, a number of studies have demonstrated that shorter needles (i.e. 5 mm or 6 mm) are equally effective in maintaining glycemic control as longer needles (i.e. 8 mm or 12.7 mm) (5e8). Shorter needles have also been associated with reduced pain, no difference in insulin leakage (5,8) and improved patient satisfaction (5,6). Methods Study design and sample population In conjunction with a substudy of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, an investigatorinitiated single-site study was performed to compare 8 mm 31 gauge pen needles to 5 mm 31 gauge pen needles in an openlabel nonrandomized design. The aim of the study was to determine the appropriate needle length for insulin injection in obese people with diabetes. The trial evaluated the safety and efficacy of treatment, as determined by glycated hemoglobin (A1C) results. Individual satisfaction as well as overall satisfaction regarding the use of both needles was measured and compared. Procedures and instruments All patients participating in the 6-month trial used an 8 mm pen needle for the first 3 months and a 5 mm pen needle for the remaining 3 months. The needles used were exactly the same, save for the difference in length. Subjects did not receive any additional counselling on injection technique at this time. At the conclusion of the trial, patients completed a questionnaire regarding pen-needle satisfaction. The questionnaire consisted of 3 parts: 8 mm penneedle satisfaction, 5 mm pen-needle satisfaction and a comparative section. The questionnaire scored items on a scale from “not at all satisfied” to “extremely satisfied.” The questionnaire also contained open-ended questions, allowing participants to state their thoughts regarding needle satisfaction. Information regarding
weight, A1C and fasting plasma glucose was obtained from the switch trial.
Statistical analysis Analysis of covariance, with treatment as a fixed effect and baseline value for the variable being analyzed, was used to analyze changes from baseline for the secondary variables.
Results Demographics The baseline, midpoint and endpoint clinical characteristics of the study group are presented in Table 1. As noted, the patients in the trial experienced no significant changes in weight, A1C or fasting plasma glucose.
Insulin dosage Subjects entered into the main trial on either basal insulin alone or basal bolus. For the purpose of this article, we concentrated on basal insulin-dose volume. At study entry, single-injection volumes of basal insulin ranged from 7 to 150 units, with a mean of 50.2 units. Data obtained at the end of the trial for largest singledose volume from the subjects indicated that 18.0% of subjects’ largest doses were between 1 and 20 units of insulin; 24.6% were between 21 and 40 units; 21.3% were between 41 and 60 units; and 36.1% were more than 60 units. In the study population, the highest proportion of patients had a single-injection insulin dose above 60 units.
Preferred pen attributes Data for the preferred pen attributes are presented in Table 2. Patients were asked to indicate their preferred pen needle for the attributes listed. If the participants found no difference between needles, the “no preference” option was selected. The 5 mm needle was preferred by 41.8% of study subjects, whereas the 8 mm needle was preferred by 27.9% of subjects. For other attributes (i.e. overall injection comfort, pain when inserting the needle into the skin and length of needle), the 5 mm needle scored higher than the 8 mm needle and also higher than the percentage of individuals who indicated no preference. Furthermore, when excluding individuals who had no preference for each attribute listed, the highest percentage of patients still preferred the 5 mm pen needle.
Table 1 Study population (n¼66)* Characteristic
Baseline
Month 3
Month 6
Weight (kg) A1C (%) FPG (mmol/L)
101.419.8 8.11.2 8.02.3
102.920.4 8.01.03 8.22.4
102.620.6 7.91.0 7.32.0
A1C, Glycated hemoglobin; FPG, fasting plasma glucose; kg, kilograms; SD, standard deviation. * Data given as mean SD.
L. Berard et al. / Can J Diabetes xxx (2015) 1e4 Table 2 Preferred pen attributes
3
Table 4 5 mm and 8 mm needle attribute scores
Variable
5 mm 8 mm No needle (%) needle (%) preference (%)
Characteristic
5 mm needle
8 mm needle
Preferred pen needle Overall injection comfort Quality from needle to needle Ease of inserting needle into skin Ease of putting needle onto the pen Least pain when inserting needle into the skin Least pain when delivering the insulin Gauge of needle Needle length
41.8 48.8 35.0 40.0 30.5 44.4
27.9 26.8 15.0 16.4 11.9 13.0
30.3 24.4 50.0 43.6 57.6 42.6
37.3 38.2 40.0
20.3 14.5 28.0
42.4 47.3 32.0
Injection comfort Needle quality Ease of inserting needle into skin Ease of putting needle on the pen Least pain when inserting needle into the skin Least pain when delivering insulin Needle gauge Needle length Overall satisfaction
4.10.8 4.20.7 4.20.7 4.30.8 4.30.9 4.21.0 4.30.9 4.01.3 3.91.1
3.71.2 4.01.0 3.91.1 4.30.8 / / 3.91.0 3.61.4 3.80.9
Injection-related issues Questions regarding injection-related issues are shown in Table 3. Each patient answered 3 questions regarding both the 5 and 8 mm pen needles. Data derived from responses indicate that the majority of individuals, whether they were delivering insulin with the 5 or 8 mm pen needle, experienced few issues with insulin delivery. Needle breakage during insulin delivery was the least frequent issue noted in both the 5 and 8 mm groups (1.9% and 3.3%, respectively). The largest discrepancy in results between the treatment groups was associated with insulin leakage at the injection site: while using the 5 mm pen needle, only 33.9% of individuals experienced leakage, whereas 41.0% using the 8 mm needle experienced leakage.
5 mm and 8 mm needle attribute scores Attribute scores for the 5 and 8 mm needles are shown in Table 4. Subjects completed a questionnaire regarding needle characteristics specific to either the 5 mm or the 8 mm pen needle. Individuals rated the needle attributes using a Likert scale, whereby “not at all satisfied” scored 1 point, while “extremely satisfied” scored 5 points. The majority of the 8 mm pen needle scores were in the upper range of the category “somewhat satisfied.” The 5 mm pen needle attribute scores were in the lower range of the “very satisfied” category.
Discussion In this study, the authors compared the effects of insulin administration between an 8 mm pen needle, and a 5 mm pen needle. The study consisted of obese individuals with poorly controlled diabetes, the majority of whom were injecting >40 units in a single dose, with a significant percentage delivering >60 units in a single injection. Based on common beliefs, it would be assumed that this study group would require, and indeed prefer, a longer pen
Table 3 Injection-related questions Variable Did you notice any insulin leakage at the injection site? Yes, n (%) No, n (%) Did you notice any bending of the needle? Yes, n (%) No, n (%) Did the needle break during injection? Yes, n (%) No, n (%)
5 mm needle
8 mm needle
19 (33.9) 37 (66.1)
25 (41.0) 36 (59.0)
9 (15.5) 48 (84.5)
12 (19.7) 49 (80.3)
1 (1.9) 52 (98.1)
2 (3.3) 59 (96.7)
needle. However, our study showed that individuals preferred the shorter pen needle. The attribute scores from the questionnaires revealed that the majority of patients experienced either no difference in pain or less pain when using shorter needles. Study subjects also found shorter needles to be the least painful upon insertion and delivery of insulin. In our study, the 5 and 8 mm pen needles used by the patients had identical features, including needle gauge (i.e. 31 gauge). Previous studies have shown that a larger needle diameter is associated with a greater frequency of painful injections (9). Because all needle characteristics were the same in this study, it can be inferred that the differences in pain reported were associated with needle length. Despite the higher doses of insulin used, there was no observed difference in insulin leakage between groups. This finding is supported by information gathered from a recent study that assessed the effectiveness of the 5 mm pen needle (10), and it found minimal leakage associated with the 5 mm pen needle in insulin doses up to 60 units. The 5 and 8 mm pen needles were equally effective in maintaining glycemic control. During both the first half of the study (when the 8 mm pen needle was used) and the second half of the study (when the 5 mm pen needle was used), both groups experienced a similar decrease in A1C. Based on the attribute scores, the 5 mm pen needle was preferred over the 8 mm pen needle. For each attribute compared, subjects revealed either greater or equivalent satisfaction with the 5 mm pen needle. The data obtained revealed a significant difference between groups with respect to injection comfort and ease of inserting the needle into skin. However, comparison of the overall preference category scores showed little difference between groups. In a similar study, which compared 6 mm needles (31 gauge) with 12.7 mm needles (29 gauge) in obese individuals, 89% of study subjects preferred the shorter needle (6). Study limitations included an open-label nonrandomized design starting all subjects at 8 mm pens for 3 months followed by 5 mm pens for 3 months. Unfortunately, this flawed method resulted from a late initiative to attempt to trial 5 mm needles in this population. The late addition to this trial of the ongoing protocol led to the questionnaires’ all being completed after 5 mm use. It is interesting to note that many subjects had not even detected a change in needle length. It is also important to note that we were able to determine the safety and efficacy in maintaining glycemic control with use of the shorter, finer needle, addressing the hesitation of healthcare providers. Conclusions The study revealed that in insulin-treated patients with type 2 diabetes using a mean single-injection volume of 50.2 units of basal insulin, the 5 mm needle was generally preferred to the 8 mm
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needle. The shorter needle was more comfortable and easier to use, while being equally effective in delivering insulin, as determined by A1C levels. Moreover, there were fewer reports of insulin leakage with the 5 mm needle, compared with the 8 mm needle. Author Disclosures Lori Berard is a paid consultant for BD Canada. No funding was received by the authors to create, deliver, analyze or report this survey. BD Canada supported the research through provision of free pen needles. Author Contributions Lori Berard and Brett Cameron contributed substantially to the design and analysis of the data and drafted the article. Vincent Woo contributed substantially to the design and analysis of the data and reviewed the article for intellectual content. References 1. Canadian Diabetes Association. 2009e10 Guide to Diabetes Products and Diabetes Medications. Toronto: Canadian Diabetes Association. Accessed, www. diabetes.ca.
2. Berard L, Desrochers F, Husband A, et al. FIT Forum for Injection Technique Canada: Recommendations for Best Practice in Injection Technique. http:// www.bd.com/resource.aspx?IDX¼25063. Accessed May 13, 2014. 3. Gibney MA, Arce CH, Byron KJ, Hirsch LJ. Skin and subcutaneous adipose layer thickness in adults with diabetes at sites used for insulin injections: Implications for needle length recommendation. Curr Med Res Opin 2010;26: 1519e30. 4. Laurent A, Mistretta F, Bottigioli D, et al. Echographic measurement of skin thickness in adults by high-frequency ultrasound to assess the appropriate microneedle length for intradermal delivery of vaccines. Vaccine 2007;25: 6423e30. 5. Hirsch LJ, Gibney MA, Albanese J, et al. Comparative glycemic control, safety and patient ratings for a new 4 mm 32 G insulin pen needle in adults with diabetes. Curr Med Res Opin 2010;26:1531e41. 6. Schwartz S, Hassman D, Shelmet J, et al. A multicenter, open-label, randomized, two-period crossover trial comparing glycemic control, satisfaction, and preference achieved with a 31 gauge 6 mm needle versus a 29 gauge 12.7 mm needle in obese patients with diabetes mellitus. Clin Ther 2004;26:1663e78. 7. Strauss K, Hannet I, McGonigle J, et al. Ultra-short (5 mm) insulin needles: Trial results and clinical recommendations. Pract Diabetes Int 1999;16:218e22. 8. G1 Kreugel, Keers JC, Kerstens MN, Wolffenbuttel BH. Randomized trial on the influence of the length of two insulin pen needles on glycemic control and patient preference in obese patients with diabetes. Diabetes Technol Ther 2011;13:737e41. 9. Arendt-Nielsen L, Egekvist H, Bjerring P. Pain following controlled cutaneous insertion of needles with different diameters. Somatosens Mot Res 2006;23: 37e43. 10. Hofman PL, Derraik JG, Pinto TE, et al. Defining the ideal injection techniques when using 5-mm needles in children and adults. Diabetes Care 2010;33: 1940e4.