How long should insulin be used once a vial is started?

Converting short-acting insulin into thermo-stable longer-acting insulin using multi-layer detachable microneedles

The detachable dissolving microneedles (DDMNs) feature an array of needles capable of being separated from the base sheet during administration. Here they were fabricated to address delivery efficiency and storage stability of insulin. The constructed insulin-DDMN is multi-layered, with 1) a hard tip cover layer; 2) a layer of regular short-acting insulin (RI) mixed with hyaluronic acid (HA) and sorbitol (Sor) which occupies the taper tip region of the needles; 3) a barrier layer situated above the RI layer; and 4) a fast-dissolving layer connecting the barrier layer to the base sheet. RI entrapped in DDMNs exhibited enhanced thermal stability; it could be stored at 40°C for 35 days without losing significant biological activity. Differential scanning calorimetric analysis revealed that the HA-Sor matrix could improve the denaturation temperature of the RI from lower than room temperature to 186°C. Tests in ex vivo porcine skin demonstrated RI delivery efficiency of 91±1.59%. Experiments with diabetic rats revealed sustained release of RI, i.e., when compared to subcutaneous injection with the same RI dose, RI-DDMNs produced slower absorption of insulin into blood circulation, delayed onset of hypoglycemic effect, longer serum insulin half-life, and longer hypoglycemic duration.

Refrigerated multi-dose insulin vials remain sterile through 6 months of use

OBJECTIVES

To evaluate sterility in refrigerated multi-dose insulin vials through 6 months of routine aspiration.

MATERIALS AND METHODS

Twelve vials of insulin, six of insulin glargine U100 (Lantus®, 10 mL multi-dose vial, Sanofi, Bridgewater, NJ) containing the preservative metacresol, and six of protamine zinc insulin U40 (ProZinc®, 10 mL multi-dose vial, Boehringer Ingelheim, Duluth, GA) containing the preservative phenol, were refrigerated and aspirated twice daily for 6 months, using a new insulin syringe each time. Three vials of each insulin type were wiped with a single-use alcohol swab before sampling. Three times weekly, aspirated samples were inoculated in Tryptic Soy Broth enrichment media and incubated for evidence of microbial growth. Positive broth was cultured and speciated. Endpoints were microbial vial contamination (defined as three consecutive positive cultures of the same organism) and completion of the six-month study period.

RESULTS

Microbial contamination was not identified in any vial throughout the study period. A total of 454 aspirated samples were cultured, one of which exhibited non-repeatable growth of Staphylococcus epidermidis. This vial was prematurely lost to breakage after 59 culture samples (29 after the positive growth).

CLINICAL SIGNIFICANCE

Refrigerated phenol- and metacresol-containing multi-dose insulin products carry minimal risk for iatrogenic infection through 6 months of use, regardless of alcohol swab preparation.

Thermal stability and storage of human insulin

BACKGROUND

Health authorities stress the temperature sensitivity of human insulin, advising protection from heat and freezing, with manufacturers suggesting low-temperature storage for intact vials, and once opened, storage at room temperature for four to six weeks, though usage time and maximum temperature recommendations vary. For human insulin, the recommendations of current shelf life in use may range from 10 to 45 days, and the maximum temperature in use varies between 25 °C and 37 °C. Optimal cold-chain management of human insulin from manufacturing until the point of delivery to people with diabetes should always be maintained, and people with diabetes and access to reliable refrigeration should follow manufacturers' recommendations. However, a growing segment of the diabetes-affected global population resides in challenging environments, confronting prolonged exposure to extreme heat due to the climate crisis, all while grappling with limited access to refrigeration.

OBJECTIVES

To analyse the effects of storing human insulin above or below the manufacturers' recommended insulin temperature storage range or advised usage time, or both, after dispensing human insulin to people with diabetes.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 12 July 2023.

SELECTION CRITERIA

We included clinical and laboratory studies investigating the storage of human insulin above or below manufacturers' recommended temperature storage range, advised usage time, or both.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We used GRADE to assess the certainty of evidence for the clinical study. Most information emerged from in vitro studies, mainly from pharmaceutical companies. There is no validated risk of bias and certainty of evidence rating for in vitro studies. We thus presented a narrative summary of the results.

MAIN RESULTS

We included 17 eligible studies (22 articles) and additional information from pharmaceutical companies. Pilot clinical study One pilot clinical study investigated temperature conditions for insulin stored for six weeks in an unglazed clay pot with temperatures ranging between 25 °C and 27 °C. The mean fall in plasma glucose in eight healthy volunteers after clay pot-stored insulin injection was comparable to refrigerator-stored insulin injection (very low-certainty evidence). In-vitro studies Nine, three and four laboratory studies investigated storage conditions for insulin vials, insulin cartridges/pens and prefilled plastic syringes, respectively. The included studies reported numerous methods, laboratory measurements and storage conditions. Three studies on prefilled syringes investigating insulin potency at 4 °C up to 23 °C for up to 28 days showed no clinically relevant loss of insulin activity. Nine studies examined unopened vials and cartridges. In studies with no clinically relevant loss of insulin activity for human short-acting insulin (SAI), intermediate-acting insulin (IAI) and mixed insulin (MI) temperatures ranged between 28.9 °C and 37 °C for up to four months. Two studies reported up to 18% loss of insulin activity after one week to 28 days at 37 °C. Four studies examined opened vials and cartridges at up to 37 °C for up to 12 weeks, indicating no clinically relevant reduction in insulin activity. Two studies analysed storage conditions for oscillating temperatures ranging between 25 °C and 37 °C for up to 12 weeks and observed no loss of insulin activity for SAI, IAI and MI. Four studies, two on vials (including one on opened vials), and two on prefilled syringes, investigated sterility and reported no microbial contamination. Data from pharmaceutical companies Four manufacturers (BIOTON, Eli Lilly and Company, Novo Nordisk and Sanofi) provided previously unreleased human insulin thermostability data mostly referring to unopened containers (vials, cartridges). We could not include the data from Sanofi because the company announced the permanent discontinuation of the production of human insulins Insuman Rapid, Basal and Comb 25. BIOTON provided data on SAI after one, three and six months at 25 °C: all investigated parameters were within reference values, and, compared to baseline, loss of insulin activity was 1.1%, 1.0% and 1.7%, respectively. Eli Lilly and Company provided summary data: at below 25 °C or 30 °C SAI/IAI/MI could be stored for up to 25 days or 12 days, respectively. Thereafter, patient in-use was possible for up to 28 days. Novo Nordisk provided extensive data: compared to baseline, after three and six months at 25 °C, loss of SAI activity was 1.8% and 3.2% to 3.5%, respectively. Loss of IAI activity was 1.2% to 1.9% after three months and 2.0% to 2.3% after six months. Compared to baseline, after one, two and three months at 37 °C, loss of SAI activity was 2.2% to 2.8%, 5.7% and 8.3% to 8.6%, respectively. Loss IAI activity was 1.4% to 1.8%, 3.0% to 3.8% and 4.7% to 5.3%, respectively. There was no relevant increase in insulin degradation products observed. Up to six months at 25 °C and up to two months at 37 °C high molecular weight proteins were within specifications. Appearance, visible particles or macroscopy, particulate matter, zinc, pH, metacresol and phenol complied with specifications. There were no data for cold environmental conditions and insulin pumps.

AUTHORS' CONCLUSIONS

Under difficult living conditions, pharmaceutical companies' data indicate that it is possible to store unopened SAI and IAI vials and cartridges at up to 25 °C for a maximum of six months and at up to 37 °C for a maximum of two months without a clinically relevant loss of insulin potency. Also, oscillating temperatures between 25 °C and 37 °C for up to three months result in no loss of insulin activity for SAI, IAI and MI. In addition, ambient temperature can be lowered by use of simple cooling devices such as clay pots for insulin storage. Clinical studies on opened and unopened insulin containers should be performed to measure insulin potency and stability after varying storage conditions. Furthermore, more data are needed on MI, insulin pumps, sterility and cold climate conditions.

The Effect of high temperature on the stability of basal insulin in a pen: a randomized controlled, crossover, equivalence trial

INTRODUCTION

Insulin is an essential medicine in the management of diabetes. When stored at high temperatures(HTs), its efficacy could rapidly decline. Therefore, appropriate storage of in-use insulin is necessary to achieve its maximum therapeutic effects. However, the ambient temperature in tropical countries is normally relatively high. This study aimed to compare the efficacies of basal insulin in a pen previously kept at 37°C for 21 days and basal insulin in a refrigerated pen (2°C-8°C). Continuous glucose monitoring (CGM) was used to evaluate daily mean glucose levels (MGLs).

RESEARCH DESIGN AND METHODS

This randomized controlled, crossover, equivalence trial recruited adults with type 2 diabetes mellitus and glycated hemoglobin levels <8% who had used insulin glargine for >3 months. Subjects were randomized for sequential use of refrigerated basal insulin followed by basal insulin kept at HT, with a 2-week washout between phases. The HT insulin pens were stored in a 37°C incubator for 21 days before use, while the refrigerated insulin pens were stored at 2°C-8°C. Study patients received 7-day CGM. The primary outcome was the difference in the groups' MGLs. The secondary outcome parameters were glucose variability represented by the standard deviation (SD), mean amplitude of glycemic excursion (MAGE), and percentage of time in range (TIR). The remaining quantity of insulin was evaluated by ultrahigh-performance liquid chromatography (UHPLC) assay.

RESULTS

Forty patients completed the study. The MGLwas 158.7±30.5 mg/dL and 157.0±40.9 mg/dL in the HT and refrigerated insulin pen groups, respectively (p=0.72). The groups had no significant differences in MAGE_7day, SD, percentage of TIR, carryover period, or treatment effects (all p>0.05). There was also no significant difference in the remaining quantity of insulin evaluated by UHPLC (p=0.97).

CONCLUSIONS

HT basal insulin pens retain their potency and have biological activity comparable to that of refrigerated pens.Trial registration number TCTR20210611002.

Formation of subvisible particles in commercial insulin formulations

The conformation and assembly of insulin are sensitive to physical and chemical variables. Insulin can misfold and form both amorphous and amyloid aggregates. Localized cutaneous amyloidosis due to insulin usage has been reported, and question remains regarding its stability in the original flasks due to storage and handling. Here we report the evaluation of the formation of aggregates in insulin formulations upon once-weekly handling and storage of the in-use cartridges at 4 °C or 37 °C for 5 weeks. Electrospray ionization mass spectrometry showed no obvious chemical decomposition. No major changes in oligomeric distribution were observed by size-exclusion chromatography. Dynamic light scattering allowed the identification of particles with high hydrodynamic radius formed during storage at 4 °C and 37 °C. Transmission electron microscopy analysis revealed the formation of amorphous material, with no clear evidence for amyloid material up to 28 days of incubation. These data support evidences for the formation of subvisible and submicrometer amorphous particulate matter in insulin formulations shortly upon use.

Thermal stability and storage of human insulin

This is a protocol for a Cochrane Review (prototype). The objectives are as follows:

To analyse the effects of storing human insulin above or below the manufacturers' recommended insulin temperature storage range or advised usage time, or both, after dispensing human insulin to people with diabetes.

Practical aspects of usage of insulin in India: Descriptive review and key recommendations

BACKGROUND AND AIMS

Insulin therapy is an integral part of diabetes management. However, reliable and easily accessible information on a number of basic facts concerning insulin therapy, including storage of insulin, managing insulin therapy during travel, nuances of insulin use while driving, and dose adjustments during sick days is lacking. This document aims to make readily available, reliable, and easy to implement information on these essential but relatively less discussed aspects of insulin therapy.

METHOD

Literature search was performed using PubMed and Cochrane Library from inception till 1^st of July 2019. The relevant topics were reviewed by a panel of 5 specialists and 23 contributing physicians and endocrinologists, who had assembled at Bengaluru, India for the 13th National Insulin Summit. After a thorough review of the literature, and following detailed discussions, the committee arrived at these recommendations.

RESULTS

Unopened vials and cartridges of insulin should be stored at 2 °C-8 °C in a refrigerator and protected from direct sunlight. For opened vials and in-use cartridges, manufacturer's instructions must be followed at all times. While traveling by air, dose adjustments are required only when flying across more than five time zones in the east or west directions. Insulin therapy should not be omitted or stopped during an acute illness; rather the doses need careful adjustments based on self-monitoring of blood glucose.

CONCLUSION

Recommendations and guidelines, covering many common aspects of insulin therapy are readily available. This consensus document aims to make recommendations for those essential aspects of insulin therapy that are crucial for its success but are relatively less known and less discussed.

Heat-stability study of various insulin types in tropical temperature conditions: New insights towards improving diabetes care

Strict storage recommendations for insulin are difficult to follow in hot tropical regions and even more challenging in conflict and humanitarian emergency settings, adding an extra burden to the management of people with diabetes. According to pharmacopeia unopened insulin vials must be stored in a refrigerator (2-8°C), while storage at ambient temperature (25-30°C) is usually permitted for the 4-week usage period during treatment. In the present work we address a critical question towards improving diabetes care in resource poor settings, namely whether insulin is stable and retains biological activity in tropical temperatures during a 4-week treatment period. To answer this question, temperature fluctuations were measured in Dagahaley refugee camp (Northern Kenya) using log tag recorders. Oscillating temperatures between 25 and 37°C were observed. Insulin heat stability was assessed under these specific temperatures which were precisely reproduced in the laboratory. Different commercialized formulations of insulin were quantified weekly by high performance liquid chromatography and the results showed perfect conformity to pharmacopeia guidelines, thus confirming stability over the assessment period (four weeks). Monitoring the 3D-structure of the tested insulin by circular dichroism confirmed that insulin monomer conformation did not undergo significant modifications. The measure of insulin efficiency on insulin receptor (IR) and Akt phosphorylation in hepatic cells indicated that insulin bioactivity of the samples stored at oscillating temperature during the usage period is identical to that of the samples maintained at 2-8°C. Taken together, these results indicate that insulin can be stored at such oscillating ambient temperatures for the usual four-week period of use. This enables the barrier of cold storage during use to be removed, thereby opening up the perspective for easier management of diabetes in humanitarian contexts and resource poor settings.

Insulin Storage: A Critical Reappraisal

Insulin, as a peptide hormone drug, is susceptible to changes in stability when exposed to environmental factors under storage. Proper storage according to the manufacturer's recommendations is important to maintain its potency and enable precise dosing for people with diabetes (PwD). While it is reasonable to assume that transport conditions and temperature are well controlled during the supply chain, little is known about insulin storage after dispensing and insulin potency at the moment of administration. Insulin is exposed to various environmental factors when carried by PwD and storage recommendations are often not met when it is stored in household refrigerators. It is difficult to assess changes in insulin potency in clinical practice, and there is a gap in the current scientific literature on insulin stability. Package leaflet recommendations only give limited information on the impact of improper storage conditions on insulin stability and guidelines by health organizations are inconsistent. Given the importance of precise dosing in diabetes care, there is a need for more transparency on insulin stability, awareness for proper storage among health care professionals and PwD as well as clear guidelines and practical storage recommendations from manufacturers and health organizations.

Commercially Available Insulin Products Demonstrate Stability Throughout the Cold Supply Chain Across the U.S

OBJECTIVE

A recent publication questioned the integrity of insulin purchased from U.S. retail pharmacies. We sought to independently validate the method used, isotope dilution solid-phase extraction (SPE) liquid chromatography mass spectrometry (LC-MS), and expand analysis to two U.S. Pharmacopeia (USP) methods (high-performance LC with ultraviolet detection and LC-MS).

RESEARCH DESIGN AND METHODS

Each method was used to evaluate nine insulin formulations, purchased at four pharmacies, within five geographic locations in the U.S.

RESULTS

All human and analog insulins measured by the USP methods (n = 174) contained the expected quantity of active insulin (100 ± 5 units/mL). When using isotope dilution SPE-LC-MS, units-per-milliliter values were well below product labeling due to unequal recovery of the internal standard compared with target insulin.

CONCLUSIONS

Insulin purchased from U.S. pharmacies is consistent with product labeling.

Wilderness Medical Society Clinical Practice Guidelines for Diabetes Management

The Wilderness Medical Society convened an expert panel in 2018 to develop a set of evidence-based guidelines for the treatment of type 1 and 2 diabetes, as well as the recognition, prevention, and treatment of complications of diabetes in wilderness athletes. We present a review of the classifications, pathophysiology, and evidence-based guidelines for planning and preventive measures, as well as best practice recommendations for both routine and urgent therapeutic management of diabetes and glycemic complications. These recommendations are graded based on the quality of supporting evidence and balance between the benefits and risks or burdens for each recommendation.

The Effects of High Altitude on Glucose Homeostasis, Metabolic Control, and Other Diabetes-Related Parameters: From Animal Studies to Real Life

Exposure to high altitude activates several complex and adaptive mechanisms aiming to protect human homeostasis from extreme environmental conditions, such as hypoxia and low temperatures. Short-term exposure is followed by transient hyperglycemia, mainly triggered by the activation of the sympathetic system, whereas long-term exposure results in lower plasma glucose concentrations, mediated by improved insulin sensitivity and augmented peripheral glucose disposal. An inverse relationship between altitude, diabetes, and obesity has been well documented. This is the result of genetic and physiological adaptations principally to hypoxia that favorably affect glucose metabolism; however, the contribution of financial, dietary, and other life-style parameters may also be important. According to existing evidence, people with diabetes are capable of undertaking demanding physical challenges even at extreme altitudes. Still, a number of issues should be taken into account, including the increased physical activity leading to changes in insulin demands and resistance, the performance of measurement systems under extreme weather conditions and the potential deterioration of metabolic control during climbing expeditions. The aim of this review is to present available evidence in the field in a comprehensive way, beginning from the physiology of glucose homeostasis adaptation mechanisms to high altitudes and ending to what real life experience has taught us.

Prevalence of insulin glargine vial use beyond 28 days in a Medicaid population

OBJECTIVES

Insulin glargine, one of the most commonly prescribed drugs for diabetes, has a 28-day limit on the use of a 10-mL (1000 units) multiple-dose vial once the bottle is punctured. If patients who are using smaller doses or are not adherent continue to use insulin glargine beyond the 28-day window, it can result in questionable stability and sterility of the product. The aim of this study was to determine the proportion of patients who used each insulin glargine vial for more than 28 days, the mean number of days the vial was used after 28 days, the reason for the extended use, and whether that use had any association with diabetes control and injection site infection.

METHODS

The study was conducted in 2 phases. Phase I was a retrospective database analysis of insulin glargine 10-mL vial use by the adult Medicaid population with type 2 diabetes served by Molina Healthcare to determine the proportion of patients who used each vial beyond 28 days. Phase II was a cross-sectional telephone interview to identify the reasons for the extended use.

RESULTS

Of the 269 patients identified, 81% used it for more than 28 days, with a mean of 43 days. Of the interviewed patients, 60% did not discard the vials after 28 days because of a lack of awareness. Patients who were aware of the 28-day limit were informed by a pharmacist or diabetes educator.

CONCLUSION

A large proportion of Medicaid patients were found to use insulin glargine past the recommended 28-day limit. More work is needed with a larger sample size to determine whether reasons besides lack of awareness affect the use of insulin glargine beyond its expiration and the role of pharmacists and diabetes educators in improving adherence to disposing of the drug after 28 days.

Insulin storage in hot climates without refrigeration: temperature reduction efficacy of clay pots and other techniques

AIM

Insulin loses potency when stored at high temperatures. Various clay pots part-filled with water, and other evaporative cooling devices, are used in less-resourced countries when home refrigeration is unavailable. This study examined the cooling efficacy of such devices.

METHODS

Thirteen devices used in Sudan, Ethiopia, Tanzania, Mali, India, Pakistan and Haiti (10 clay pots, a goat skin, a vegetable gourd and a bucket filled with wet sand), and two identical commercially manufactured cooling wallets were compared. Devices were maintained according to local instructions. Internal and ambient temperature and ambient humidity were measured by electronic loggers every 5 min in Khartoum (88 h), and, for the two Malian pots, in Bamako (84 h). Cooling efficacy was assessed by average absolute temperature difference (internal vs. ambient), and % maximal possible evaporative cooling (allowing for humidity).

RESULTS

During the study period, mean ambient temperature and humidity were 31.0°C and 32.0% in Khartoum and 32.9°C and 39.8% in Bamako. All devices reduced the temperature (P < 0.001) with a mean (sd) reduction from 2.7 ± 0.5°C to 8.3 ± 1.0°C, depending on the device. When expressed as % maximal cooling, device efficacy ranged from 20.5% to 71.3%. On cluster analysis, the most efficacious devices were the goat skin, two clay pots (from Ethiopia and Sudan) and the suspended cooling wallet.

CONCLUSIONS

Low-cost devices used in less-resourced countries reduce storage temperatures. With more efficacious devices, average temperatures at or close to standard room temperature (20-25°C) can be achieved, even in hot climates. All devices are more efficacious at lower humidity. Further studies are needed on insulin stability to determine when these devices are necessary.

How long can a vial of insulin be used after it is started: where are we 10 years later?

In August 2003, I wrote a commentary entitled "How Long Can a Vial of Insulin be Used After It Is Started." The commentary included comments from each of the 3 insulin manufacturers, as well as the American Diabetes Association. Anyone reading the article quickly realized that there was little agreement among the insulin manufacturers and just as little clarity to this question. Over the ensuing 10 years, there has been little or no effort made by either the Food and Drug Administration (FDA) or the insulin manufacturers to clarify this issue of insulin storage after a bottle is started. Current package inserts list varying times from 28 to 42 days, while the latest recommendation from the American Diabetes Association gives a uniform 1-month time limit. I would therefore propose that insulin manufacturers begin putting on every insulin vial and pen, in addition to the expiration date, the amount of time that particular insulin should be used after it is started. In addition there should be a box for the patient to write the starting date directly onto the vial or pen. This would eliminate the need for uniformity of recommendations; all the patient would have to do is read the instructions written on the insulin vial or pen.

Economic impact of converting from 10-mL insulin vials to 3-mL vials and pens in a hospital setting

PURPOSE

The economic impact associated with the conversion from 10-mL vials of insulin to 3-mL vials and pens at a community hospital was assessed.

METHODS

Pharmacy purchasing and administrative data from Providence St. Vincent Hospital in Portland, Oregon, were used in this analysis. The hospital converted floor-stock 10-mL vials of insulin in October 2010 to individual patient supply (IPS) 3-mL vials and pens. Insulin acquisition costs from the nine-month preconversion period were compared with those during the nine-month postconversion period.

RESULTS

Before the conversion, total acquisition costs were $168,783 for 5,086,500 units of insulin. After the conversion, total acquisition costs were reduced by 8.6% (to $154,303) and units purchased were reduced by 33.1% (to 3,404,900 units of insulin). The analyses also examined the results of converting to 3-mL vials of rapid-, short-, or intermediate-acting insulin to 3-mL pens of long-acting insulin analog. Conversion from 10- to 3-mL vials was associated with a 37.6% reduction in units of insulin and a 23.5% reduction in acquisition costs. In contrast, switching from 10-mL vials to 3-mL pens was associated with a 10.1% increase in costs, despite the fact that there was a 11.5% reduction in units purchased.

CONCLUSION

Conversion from floor-stock 10-mL insulin vials to IPS 3-mL insulin vials or pens reduced the number of units of insulin purchased and expenditures for insulin. The overall cost savings was driven by the conversion from 10- to 3-mL vials, whereas cost increased for the conversion of 10-mL vials to 3-mL pens for long-acting insulin analogs.

Physical activity at altitude: challenges for people with diabetes: a review

BACKGROUND

A growing number of subjects with diabetes take part in physical activities at altitude such as skiing, climbing, and trekking. Exercise under conditions of hypobaric hypoxia poses some unique challenges on subjects with diabetes, and the presence of diabetes can complicate safe and successful participation in mountain activities. Among others, altitude can alter glucoregulation. Furthermore, cold temperatures and altitude can complicate accurate reading of glucose monitoring equipment and storage of insulin. These factors potentially lead to dangerous hyperglycemia or hypoglycemia. Over the last years, more information has become available on this subject.

PURPOSE

To provide an up-to-date overview of the pathophysiological changes during physical activity at altitude and the potential problems related to diabetes, including the use of (continuous) blood glucose monitors and insulin pumps. To propose practical recommendations for preparations and travel to altitude for subjects with diabetes.

DATA SOURCES AND SYNTHESIS

We researched PubMed, medical textbooks, and related Internet sites, and extracted human studies and data based on relevance for diabetes, exercise, and altitude.

LIMITATIONS

Given the paucity of controlled trials regarding diabetes and altitude, we composed a narrative review and filled in areas lacking diabetes-specific studies with data obtained from nondiabetic subjects.

CONCLUSIONS

Subjects with diabetes can take part in activities at high, and even extreme, altitude. However, careful assessment of diabetes-related complications, optimal preparation, and adequate knowledge of glycemic regulation at altitude and altitude-related complications is needed.

Administration Technique and Storage of Disposable Insulin Pens Reported by Patients With Diabetes

Purpose

The purpose of the study was to evaluate insulin injection technique and storage of insulin pens as reported by patients with diabetes and to compare correct pen use to initial education on injection technique, hemoglobin A1C, duration of insulin therapy, and duration of insulin pen.

Methods

Cross-sectional questionnaire orally administered to patients at a university-affiliated primary care practice. Subjects were patients with diabetes who were 18 years or older and prescribed a disposable insulin pen for at least 4 weeks. A correct usage score was calculated for each patient based on manufacturer recommendations for disposable insulin pen use. Associations were made between the correct usage score and certainty in technique, initial education, years of insulin therapy, duration of pen use, and hemoglobin A1C.

Results

Sixty-seven patients completed the questionnaire, reporting total use of 94 insulin pens. The 3 components most often neglected by patients were priming pen needle, holding for specific count time before withdrawal of pen needle from skin, and storing an in-use pen. For three-fourths of the insulin pens being used, users did not follow the manufacturer’s instructions for proper administration and storage of insulin pens. Correct usage scores were significantly higher if initial education on insulin pens was performed by a pharmacist or nurse.

Conclusions

The majority of patients may be ignoring or unaware of key components for consistent insulin dosing using disposable insulin pens; therefore, initial education and reeducation on correct use of disposable insulin pens by health care professionals are needed.

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

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

Experiences of patients with insulin-treated diabetes in conscript military service

AIMS

To determine how young adults with insulin therapy manage daily care of diabetes during the physically demanding conditions of conscript military service, and to evaluate the effects of military service on glycaemic control and on the incidence of acute diabetic complications.

METHODS

An observational study of 47 young male volunteer conscripts receiving insulin therapy was carried out at the Signal Regiment in Riihimäki from January 2001 to July 2005. Outcome measures were drop-out rate from service, management of diabetes care, glycaemic control, and occurrence of severe hypoglycaemia or ketoacidosis during service.

RESULTS

Forty (85%) diabetic conscripts completed service, with service time ranging from 180 to 362 days, and seven (15%) interrupted service. One-third of conscripts reported difficulties during military training with insulin injections and blood glucose testing. The mean HbA(1c) during service increased by 0.6% units (P = 0.007) from baseline. Five events of severe hypoglycaemia in three conscripts (overall incidence rate 0.15 per patient-year) and one ketoacidosis event occurred. Diabetic conscripts were chosen for leadership training more often than non-diabetic conscripts.

CONCLUSIONS

Our data suggest that selected and motivated adolescents on insulin therapy can manage the daily care of diabetes and maintain appropriate glycaemic control during service, although the risk of severe hypoglycaemia exists.

A Critical Appraisal of the Role of Insulin Analogues in the Management of Diabetes Mellitus

Insulin is one of the oldest and best studied treatments for diabetes mellitus. Despite many improvements in the management of diabetes, the nonphysiological time-action profiles of conventional insulins remain a significant obstacle. However, the advent of recombinant DNA technology made it possible to overcome these limitations in the time-action profiles of conventional insulins. Used as prandial (e.g. insulin lispro or insulin aspart) and basal (e.g. insulin glargine) insulin, the analogues simulate physiological insulin profiles more closely than the older conventional insulins. If rapid-acting insulin analogues are used in the hospital, healthcare providers will need a new mind-set. Any error in coordination between timing of rapid-acting insulin administration and meal ingestion may result in hypoglycaemia. However, guidelines regarding in-hospital use of insulin analogues are few. The safety profile of insulin analogues is still not completely established in long-term clinical studies. Several studies have shown conflicting results with respect to the tumourigenic potential of this new class of agents. The clinical implications of these findings are not clear. Although novel insulin analogues are promising 'designer drugs' in our armamentarium to overcome some of the limitations of conventional insulin therapy, cost may be a limiting factor for some patients.