Diabetes Research and Clinical Practice 77 (2007) 231–236
`
`www.elsevier.com/locate/diabres
`
`Incidence of lipohypertrophy in diabetic patients and
`a study of influencing factors
`
`Bahar Vardar a, Sevgi Kızılcı b,*
`a Go¨zde Hospital, Malatya, Turkey
`b Dokuz Eylu¨l U¨ niversitesi, School of Nursing, Turkey
`
`Received 14 August 2006; received in revised form 14 November 2006; accepted 25 December 2006
`Available online 15 February 2007
`
`Abstract
`
`This study examines the incidence of lipohypertrophy in diabetic individuals as well as the factors that have an influence on
`causing this condition. In consideration of the period of development of lipohypertrophy, the research sampling consisted of 215
`diabetics who had been using insulin for at least 2 years. Observation and palpation techniques were used in assessing
`lipohypertrophy in these diabetics. Data were evaluated using percentages, x2 and logistic regression analysis. Results of the
`study established lipohypertrophy in 48.8% of the individuals comprising the sampling. It was seen that the incidence of
`lipohypertrophy in these individuals was affected by their level of education, the frequency that they changed needles, the frequency
`of changing their injection sites and the amount of time they had been using insulin, the difference proving to be statistically
`significant ( p < 0.05). In the logistic regression analysis, it was found that the amount of time insulin had been used ( p = 0.001), the
`frequency of changing injection sites ( p = 0.004) and the frequency of changing needles ( p = 0.004) had an influence on the
`development of lipohypertrophy. These results show that the amount of time insulin is used and the procedure for injection both
`affect the development of lipohypertrophy.
`# 2007 Elsevier Ireland Ltd. All rights reserved.
`
`Keywords: Lipodystrophy; Lipohypertrophy; Insulin management; Rotation of injection site
`
`1. Introduction
`
`With the technological advances creating changes in
`living conditions in the last 20 years, there has been an
`increase observed both in the number of patients
`diagnosed with diabetes and in the number of insulin
`users. With this rise in the subcutaneous use of insulin,
`dermatological complications related to treatment have
`come to the fore. One of
`these dermatological
`complications is lipohypertrophy, which is defined as
`
`* Corresponding author at: Dokuz Eylu¨l U¨ niversitesi, Hems¸irelik
`Yu¨ksekokulu, 35340 I˙nciraltı, I˙zmir Turkey.
`E-mail addresses: baharvardar@yahoo.com (B. Vardar),
`sevgi.kizilci@deu.edu.tr (S. Kızılcı).
`
`the changes that develop in the fat tissue caused by
`injections of insulin [1].
`The incidence of lipohypertrophy is so high as not to
`be ignored. In studies conducted on Type 1 diabetic
`patients, Kordonouri et al. [2] reports an incidence of
`48%, Partanen and Rissanen [3] an incidence of 34.5%,
`and Raile et al.
`[4] an incidence of 27.1% of
`lipohypertrophy in their patients. In addition, McNally
`et al. discloses an incidence of lipohypertrophy of 28%
`in Type 2 diabetic patients while Teft speaks of an
`incidence of lipohypertrophy of 57% in both Type 1 and
`Type 2 diabetics [5,6]. Hauner et al. as well have
`established an incidence of 28.7% in Type 1 diabetic
`patients, reporting at the same time that this proportion
`drops to 3.6% in Type 2 diabetics [7].
`
`0168-8227/$ – see front matter # 2007 Elsevier Ireland Ltd. All rights reserved.
`doi:10.1016/j.diabres.2006.12.023
`
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`232
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`B. Vardar, S. Kızılcı / Diabetes Research and Clinical Practice 77 (2007) 231–236
`
`A look into the literature reveals that lipohyper-
`trophy is mostly seen in Type 1 diabetics [2–4,6,7]. The
`factors influencing the development of lipohypertrophy
`have been cited as the amount of time insulin has been
`used, the number of daily injections, gender, body mass
`index (BMI), injection sites, rotation of sites, the use of
`pens as opposed to syringes, the length of the needle and
`the frequency needles are changed [2–10].
`Early diagnosis of lipohypertrophy is very important.
`Pain sensations diminish in areas where lipohypertrophy
`has formed and for that reason diabetic patients prefer to
`always administer their injections in the same site. As a
`result, lipohypertrophic tissue increases. Because insulin
`absorption is restricted in the area where lipohypertrophy
`has developed, the risk of hyperglycemia arises [8,9,11–
`13]. Partanen and Kordonouri have shown in their
`research that metabolic control is poor in patients with
`lipohypertrophy [2,3]. Since these diabetics with lipohy-
`pertrophy have poor metabolic control, they are at risk of
`developing complications. It has been established that
`when a portion of the insulin injected into an area with
`lipohypertrophy cannot be absorbed, not only will there
`be the danger of hyperglycemia but conversely, when the
`same dose of insulin is injected into an area without
`lipohypertrophy, the insulin will be completely absorbed
`and the risk of hypoglycemia will then emerge [5,13–15].
`It has been indicated that health-care providers and
`patients do not take this important problem seriously and
`consequently fail to have control over this situation
`[6,10]. It is very important in the treatment of diabetes
`that these complications be warded off through the
`correct application of insulin, the inevitable element in
`diabetic treatment. In the case of lipohypertrophy, it is
`vital that this condition is recognized so that the treatment
`can be readjusted. It is for this reason that diabetic care-
`providing nurses play a major role in treatment. Both
`healthcare personnel and diabetic individuals should be
`aware of the significance of lipohypertrophy, seek its
`early diagnosis and know what the risk factors involved
`are. Learning about how frequent lipohypertrophy is seen
`in patients and the factors that influence the condition will
`be valuable guidelines to follow for both diabetic patients
`and their nurses. So this study was planned as definitive
`research, designed to determine the incidence of
`lipohypertrophy in diabetic patients as well as the
`factors influencing the condition.
`
`2. Materials and methods
`
`2.1. Subjects and design
`
`The work was conducted during the period 5 August 2004–
`15 January 2005 at Dokuz Eylu¨l University Medical School
`
`Hospital and at the Ege University Medical School Hospital.
`The sampling comprised 215 diabetics who applied to the
`adult endocrinology polyclinics of these two university hos-
`pitals.
`Considering the period of development of lipohypertrophy,
`patients were chosen who had been using insulin for at least 2
`years and had consented voluntarily to be included in the
`research [7]. None of the diabetic individuals were using
`syringes; all of them were using insulin pens. The essential
`clinical characteristics are summarized in Table 1.
`Contact was made with the Endocrinology Departments
`of the Dokuz Eylu¨l University and Ege University Medical
`School Hospitals and the necessary permissions were
`obtained.
`Data were collected by the researcher through the method
`of face-to-face contact. The questionnaire was prepared after a
`study of relevant literature and following suggestions given by
`the advisor.
`
`Table 1
`Clinical characteristics of study populations (n = 215) [age (X = 59.6)]
`
`Number
`
`%
`
`Gender
`Women
`Men
`
`Education
`Elementary
`High School
`University
`
`BMI
`Normal
`Overweight
`Obese
`
`Needle change frequency
`At every injection
`At every two–three injections
`At every four–five injections
`When cartridge is finished
`
`Length of needle
`8 mm
`5 mm
`
`Change of site frequency
`A different site at every injection
`A week at each site
`Haphazardly
`Using only one site
`
`Duration of insulin use
`0–5 years
`6–10 years
`11–15 years
`16–20 years
`
`Diabetes type
`Type 1
`Type 2
`
`137
`78
`
`93
`86
`36
`
`72
`86
`57
`
`74
`82
`48
`11
`
`164
`51
`
`39
`126
`21
`29
`
`66
`59
`57
`33
`
`31
`184
`
`63.7
`36.3
`
`43.3
`40
`16.7
`
`33.5
`40
`26.5
`
`34.5
`38.1
`22.3
`5.1
`
`76.3
`23.7
`
`18.1
`58.6
`9.8
`13.5
`
`30.7
`27.4
`26.5
`15.4
`
`14.4
`85.6
`
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`B. Vardar, S. Kızılcı / Diabetes Research and Clinical Practice 77 (2007) 231–236
`
`233
`
`2.2. Variables of study
`
`The study’s dependent variable was the observation of
`lipohypertrophy in diabetic patients. Independent variables
`were gender, education, body mass index, frequency of needle
`change, needle length, frequency of changing site, and length
`of insulin use.
`
`2.3. Assesment of lipohypertrophy
`
`Observation and the palpation technique were used in
`assessing lipohypertrophy in diabetic individuals. Lipohyper-
`trophy was assessed as either ‘‘present’’ or ‘‘not present’’.
`Lipohypertrophy present: The presence of a noticeable or
`palpable/unpalpable lump on the injection site.
`Lipohypertrophy not present: No difference in the injection
`site [2,4].
`
`2.4. Statistical analysis
`
`Data were assessed using an SPSS package program.
`Clinical characteristics of study populations was evaluated
`using percentages. The factors influencing lipohypertrophy
`and the development of lipohypertrophy were evaluated using
`x2-test. Independent variables influencing the occurrence of
`lipohypertrophy was evaluated logistic regression analysis.
`
`3. Results
`
`The factors affecting lipohypertrophy and the status
`of lipohypertrophy in the 215 diabetics included in the
`study have been shown in Table 2.
`
`3.1. Influence of individual characteristics of
`diabetics on the development of lipohypertrophy
`
`3.1.1. Gender
`Of the cases diagnosed as lipohypertrophy, 50.45%
`were women and 44.9% were men. No statistically
`significant difference was found between the gender of
`diabetic individuals and the incidence of lipohyper-
`trophy ( p > 0.05).
`
`3.1.2. Education
`While the proportion of elementary school graduates
`with lipohypertrophy was 58.1%, 44.2% were high
`school graduates and only 33.3% were university
`graduates. The difference was found to be statistically
`significant ( p < 0.05). Advanced analysis showed that
`this difference stemmed from the elementary school
`graduate group that displayed the most incidence of
`lipohypertrophy. As the level of education increased it
`was found that the proportional incidence of developing
`lipohypertrophy fell. Logistical regression analysis,
`
`however, showed that education was a negligible factor
`in the development of lipohypertrophy.
`
`3.1.3. Body mass index
`Lipohypertrophy was found in 40.3% of individuals
`classified as having a normal body mass index. It was
`seen in 57% of overweight individuals and in 45.6% of
`those defined as obese. The difference between body
`mass index classification in diabetics and the incidence
`of lipohypertrophy was not found to be statistically
`significant ( p > 0.05).
`
`3.1.4. Needle change frequency
`While lipohypertrophy was observed in 20.3%
`of diabetics who changed their needle at every
`injection, this proportion was 51.2% in those who
`changed needles every two–three injections, 75% in
`those that changed every four–five injections and
`100% in those that changed only when the cartridge
`was finished. A statistically significant difference was
`seen between needle change frequency in diabetics
`lipohypertrophy ( p < 0.05).
`and the incidence of
`Advanced analysis
`showed that
`this difference
`stemmed from the group that changed needles at
`every injection, where lipohypertrophy was seen
`the least. It has thus been observed that using the
`same needle more than once increases the risk of
`lipohypertrophy.
`
`3.1.5. Length of needle
`Lipohypertrophy was seen in 47.6% of the 164
`diabetics in the study who were using an 8 mm needle
`and in 51% in the 51 diabetics who were using a 5 mm
`needle. No statistically significant difference was seen
`between the length of needle used by diabetics and the
`incidence of lipohypertrophy ( p > 0.05).
`
`3.1.6. Change of site frequency
`While lipohypertrophy was seen in 76.9% of the
`diabetics who changed injection sites at each injec-
`tion, the condition was seen in 86% of the persons who
`used only one injection site. Lipohypertrophy was also
`observed in 90.5% of persons who chose the injection
`site at random. Lipohypertrophy was seen in only
`23.8% of persons who rotated the injection site
`weekly. A statistically significant difference was seen
`( p < 0.05)
`in diabetic
`individuals between the
`occurrence of lipohypertrophy and the frequency of
`their changing the injection site. Advanced analysis
`showed that the difference stemmed from the group of
`patients that had been rotating the injection site
`weekly.
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`234
`
`B. Vardar, S. Kızılcı / Diabetes Research and Clinical Practice 77 (2007) 231–236
`
`Table 2
`Factors influencing lipohypertrophy and the status of lipohypertrophy
`
`Lipohypertrophy status
`
`Present
`
`Not present
`
`Total
`
`Number
`
`%
`
`Number
`
`%
`
`Number
`
`%
`
`Gender
`Women
`Men
`
`Education
`Elementary
`High School
`University
`
`BMI
`Normal
`Overweight
`Obese
`
`Needle change frequency
`At every injection
`At every two–three injections
`At every four–five injections
`When cartridge is finished
`
`Length of needle
`8 mm
`5 mm
`
`Change of site frequency
`A different site at every injection
`A week at each site
`Haphazardly
`Using only one site
`
`Duration of insulin use
`0–5 years
`6–10 years
`11–15 years
`16–20 years
`
`69
`35
`
`54
`38
`12
`
`29
`49
`26
`
`15
`42
`36
`11
`
`78
`26
`
`30
`30
`19
`25
`
`8
`24
`44
`28
`
`50.4
`44.9
`
`58.1
`44.2
`33.3
`
`40.3
`57
`45.6
`
`20.3
`51.2
`75
`100
`
`47.6
`51
`
`76.9
`23.8
`90.5
`86.2
`
`12.1
`40.7
`77.2
`84.8
`
`68
`43
`
`39
`48
`24
`
`43
`37
`31
`
`59
`40
`12
`–
`
`86
`25
`
`9
`96
`2
`4
`
`58
`35
`13
`5
`
`49.6
`55.1
`
`41.9
`55.8
`66.7
`
`59.7
`43
`54.4
`
`79.7
`48.8
`25
`–
`
`52.4
`49
`
`23.1
`76.2
`9.5
`13.8
`
`87.9
`59.3
`22.8
`15.2
`
`137
`78
`
`93
`86
`36
`
`72
`86
`57
`
`74
`82
`48
`11
`
`164
`51
`
`39
`126
`21
`29
`
`66
`59
`57
`33
`
`0.43837 ( p > 0.05)
`
`0.02520 ( p < 0.05)
`
`0.09965 ( p > 0.05)
`
`0.0000 ( p < 0.05)
`
`0.66954 ( p > 0.05)
`
`0.0000 ( p < 0.05)
`
`0.0000 ( p < 0.05)
`
`100.0
`100.0
`
`100.0
`100.0
`100.0
`
`100.0
`100.0
`100.0
`
`100.0
`100.0
`100.0
`100.0
`
`100.0
`100.0
`
`100.0
`100.0
`100.0
`100.0
`
`100.0
`100.0
`100.0
`100.0
`
`3.1.7. Duration of insulin use
`While lipohypertrophy was seen in only 12.1% of the
`diabetics in the study who had been using insulin for
`less than 5 years, this proportion was 40.7% in those
`who had been using insulin for 6–10 years, 77.2% in
`those using insulin for 11–15 years and 84.8% in users
`of 16–20 years. A statistically significant difference
`( p < 0.05) was
`seen between the occurrence of
`lipohypertrophy and the duration of use of insulin in
`diabetic individuals. Advanced analysis showed that the
`difference stemmed from the group that had been using
`insulin for 0–5 years.
`A logistic regression analysis was carried out to
`determine which of the four variables that proved to be
`significant in this study, conducted to establish the
`incidence of lipohypertrophy in diabetics and the
`factors having an influence on this condition, had an
`
`effect on the occurrence of lipohypertrophy (Table 3).
`The analysis showed that the effect of education was not
`statistically significant. The duration of insulin use
`( p = 0.001),
`the
`frequency of
`changing needles
`( p = 0.004) and the frequency of changing sites
`( p = 0.004), however, were found to be statistically
`significant.
`
`Table 3
`Logistic regression analysis of independent variables influencing the
`occurrence of lipohypertrophy
`
`Variables
`
`Education
`Frequency of needle change
`Frequency of site change
`Duration of insulin use
`
`B
`P
`OR
`95% CI
`0.345 0.333 0.709 0.353–1.424
`1.036 0.004 2.819 1.403–5.662
`1.303 0.004 3.682 1.531–8.855
`1.172 0.001 3.228 1.636–6.366
`
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`
`235
`
`4. Discussion
`
`The most common local complication seen in
`diabetic individuals treated with insulin is lipohyper-
`trophy. This study has revealed that
`the factors
`influencing the development of lipohypertrophy are
`the duration of insulin use, the frequency of changing
`needles, and the frequency of changing injection sites.
`As the duration of
`insulin use increases,
`the
`incidence of lipohypertrophy also rises. This might
`be explained by the fact
`that
`the growth inducing
`character of insulin has a multiplying effect on the fat
`tissue. Previous research has disclosed similar results
`[7,8]. Diabetes mellitus is a chronic disease. Treatment
`with insulin must be continued on a life-long basis.
`There is nothing that can be done for the length of the
`treatment; we can only control the other factors that
`have an effect on the development of lipohypertrophy.
`This study has found that two important controllable
`factors that influence the development of lipohyper-
`trophy are the frequency of changing injection sites and
`the frequency of changing needles.
`The literature indicates that in diabetics using insulin,
`not appropriately rotating sites is one of the main
`instigators of lipohypertrophy [7,15]. In our study, the
`incidence of lipohypertrophy in patients rotating their
`injection sites weekly was much lower than in the other
`groups. However, it was also found that the incidence of
`lipohypertrophy was high in patients rotating the
`injection site at each injection and at a percentage
`similar to those who did not engage in rotation. This
`finding is indicative of the importance of the form of
`rotation. If a diabetic uses at least six injection sites (right
`and left arms, abdomen, legs) and uses each injection site
`for 1 week, it will be 5 weeks before he/she returns to the
`same site. During this time the tissue is free from the
`effect of insulin, which is at the same time a growth
`hormone. The development of lipohypertrophy is in this
`way diminished because of the lessening effect of insulin
`in the area.
`the diabetic individuals comprising the
`All of
`sampling in this study were given training beforehand
`about how to rotate an area by using it exclusively for
`only 1 week. In spite of this, however, a significant
`portion of the group (41.4%) insisted on either using the
`same area, selecting an area haphazardly or using a
`different site at every injection. The reluctance to
`conform to the training may be explained in various
`ways. The first factor might be the form of training that
`was used. Literature indicates that classical diabetic
`education is not as effective as self-management
`education using behavioral and psycho-social strategies
`
`[16–18]. The individuals comprising the sampling in
`this research were taught with the classical education
`model. For this reason,
`instead of only providing
`information, we must have faith that training will be
`more effective if the educator is a good listener, if the
`patient’s needs can be assessed properly and if the
`patient can be taught how to make his/her own
`assessment. Another reason the diabetics in the study
`did not conform to correct rotation habits may be that
`the injection sites kept on being re-used since there was
`no pain sensation during the injection in those areas due
`to the development of lipohypertrophy [1,11,13].
`Another
`factor
`influencing the development of
`lipohypertrophy is the frequency of changing needles.
`In our study, the less frequently the needle was changed,
`the more frequently seen was
`the incidence of
`lipohypertrophy. This result is supported by previous
`studies [6,8,15]. Needle tips are now minutely cut and
`siliconed under methods of advanced technology in order
`to lessen pain and reduce damage to the tissue. The use of
`the same needle causes damage to the tip of the needle
`and leads to the loss of the silicone coating, preparing a
`foundation for tissue damage and subsequent develop-
`ment of lipohypertrophy [6,19–21]. For this reason, it can
`be said that using the same needle for more than one
`injection increases the risk of lipohypertrophy.
`All of the diabetics comprising the sampling in this
`study were using insulin pens. In the research studied, it
`was found that the incidence of lipohypertrophy in pen-
`users was higher than in those using syringes. The reason
`the diabetic individuals in the study had a high percentage
`of lipohypertrophy can be explained by the fact that by
`using the insulin pen, they were using the same needle
`more than once. These findings show that the issue of
`changing the needle on insulin pens frequently should be
`addressed. Because the healthcare institutions in our
`country do not provide diabetic patients with a separate
`needle for each injection, this matter must first be
`discussed with the health authorities.
`Our study showed that education, gender, body mass
`index and the length of needle did not have an influence
`on the development of lipohypertrophy. There are
`examples in literature that however indicate that these
`factors do in fact affect
`the development of
`the
`condition. At the same time, there are also studies that
`indicate that the same factors have no effect on the
`development of lipohypertrophy [2,5–8].
`
`5. Conclusions
`
`Our findings strengthen the studies that have been
`carried out on the subject of lipohypertrophy to date.
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`236
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`B. Vardar, S. Kızılcı / Diabetes Research and Clinical Practice 77 (2007) 231–236
`
`The incidence of lipohypertrophy increases as the
`period of insulin use increases. In addition, incorrect
`rotation and failure to change needles are two problems
`that have been established related to insulin injection
`techniques. In conclusion, more attention must be given
`to the care of persons who have used insulin for a long
`period of time. We must also see to it that diabetics
`rotate an injection site after using it for 1 week and that
`they change needles after every one or two injections.
`Furthermore, we must ensure that
`lipohypertrophy
`checks are part of the routine examination procedures of
`polyclinics and hospitals.
`The findings of our study at the same time bring out
`certain questions to be answered. These are questions
`such as ‘‘Why don’t diabetics follow the recommenda-
`tions for their injections? How can we ensure effective
`training?’’ As nurses, we must understand, listen to, and
`respect the personal characteristics of the patients to
`whom we provide care. Future studies may delve into
`the reasons why complications cannot be prevented
`during the treatment of diabetic patients.
`
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`[4] K. Raile, V. Noelle, H.P. Schawarz, Insulin antibodies are
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`[6] G. Teft, Lipohypertrophy: patient awareness and implications for
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