BACKGROUND: Insulin is a common therapy in the treatment of diabetes mellitus type 1 and 2. With the advent of intermediate-acting and long-acting insulin products, basal insulin therapy has become a common practice usually utilized to reduce the number of injections needed to administer or in combination with a short-acting insulin product in the basal–bolus insulin regimens.
The original insulins created to have longer durations of action were the NPH insulins which utilized a crystalline complex between the insulin and protamine.2 In more recent years, newer basal insulins such as Levemir and Lantus have come onto the market which do not rely on the use of protamine-insulin complexes and also claim to last longer (possibly up to single dose a day administration) with no peak activity. The lack of peak activity promises to reduce hypoglycemia risk and to provide a more basal-like dosing.1,3 The original insulins used as bolus insulin therapy were isolated from either animal or human sources. Today, the standard of isolated insulin therapies is regular human insulin. Like the long acting insulin products, recent years have seen the emergence of rapid acting insulin analogues. These rapid insulins promise to have higher efficacy and safety due to rapid onset (for meal time administration) and shorter duration of action.1,4,5
While the newer insulin products claim to have benefits of duration of action and less risk of hypoglycemia, they come at a higher cost than the regular human insulin and NPH insulin products. The average patient admitted to hospice care usually does not have insulin therapy related to the terminal diagnosis — with some obvious exceptions such as pancreatic cancer. The following is an analysis of the benefits and claimed convenience of the newer designer insulin analogues and how they could be substituted with regular human insulin and NPH insulin.
COMPARATIVE ANALYSIS: All three insulins (glarginine, detemir, and NPH) appear to have an onset of 1 to 2 hours. Peak efficacy of Levemir is at a narrow range of 6 to 8 hours (in graphic data in package insert; the analysis section states that there is “no pronounced peak”) versus a more unpredictable reported peak between 3 and 12 hours of Humulin N. Lantus appears to have the most data to support the assertion that there is no pronounced peak of activity with full onset occurring around 4-5 hours after administration and remaining constant throughout the duration of the trials. Duration of action appears to be similar between NPH and Levemir treatments which officially list their durations of action in package inserts as “up to 24 hours.”2,3 Lantus claims to have a constant level up to 24 hours as well, however all data collection ended at 24 hours demonstrating that it could have a greater than 24 hours duration.15
The variable ranges of duration of action and time to peak pharmacodynamic response could be affected by multiple factors such as patient metabolism, site of administration, administration technique, storage conditions of the product, etc. It appears that the NPH insulin (Humulin N) would be more prone to administration technique errors due to the necessity to remember to resuspend the crystalline suspension dosage form by rolling the vials prior to administration. While Lantus has no particularly documented half-life, Levemir has a similar but slightly greater half-life than NPH which could be the result of its being albumin bound which protects some of the insulin from clearance.6,7 There does not appear to be data readily available on the effects of insulin detemir in patients with hypoalbuminemia which is a common condition as a patient's nutritional status declines in end-of life care.
For hypoglycemia risk, the current American Diabetes Association guidelines state that NPH insulin has a higher risk of hypoglycemia over the newer basal insulins Levemir and Lantus. However, in comparative trials, only one case of severe hypoglycemia will be prevented for every thirty-seven patients treated with Levemir than if all thirty-seven patients were to receive NPH. In the case of non-severe hypoglycemia, the risk was similar between Levemir and NPH.3 In trials of Lantus vs NPH both combined with regular human insulin as a bolus, Lantus would need to be used in 97 patients than if they were treated with NPH in order to prevent only one case of severe hypoglycemia.15
RESULTS: Given the similar onset, peak, and duration, Humulin N properly dosed twice daily could be used as a treatment alternative to Levemir or Lantus as a basal insulin alternative. While the newer insulins have a significantly less pronounced peak than NPH insulin,2,3,15 Humulin N has a long enough duration of action to be utilized as a longer acting insulin replacement therapy. It appears that hypoglycemia risk is similar between all three insulin therapies. However, it should be noted that Levemir and Lantus have been shown to have a more predictable pharmacodynamic profile over NPH insulin — not more effective6 — and that NPH insulin has the potential for hypersensitivity to the protamine. Regardless, all three insulin therapies can be considered equiefficacious (not equipotent) and can be utilized as basal insulin supplementation.
CONCLUSIONS: The choice between any of the available insulin products appears to be mostly based on clinical safety instead of clinical efficacy. The data suggests that any basal-bolus regimen can be considered equiefficacious if properly managed. The selection on which agents to use for outpatient therapy may need to take into account some of those minute differences in safety or dosing depending on individual patient factors. While true, once a day dosing of Lantus or Levemir may seem appealing since it reduces the number of invasive injections during palliative care, the need for basal insulin therapy decreases as nutritional intake declines. In addition, the existence of mixed human insulin products (Novolin 70/30 and Humulin 70/30) may increase convenience since they can provide both bolus coverage and basal insulin in only one or two administrations a day and can be more easily adjusted for changes in intake than the pure basal therapies. Utilization of the older human insulin products can be beneficial from a cost-effectiveness potential especially in the hospice industry since regular human and NPH insulin are available as a lower cost alternative. The cost-effectiveness of human insulin products can be significant since most hospices will not usually have sufficient insulin utilization for purchasing power as some larger health care institutions.
1. American Diabetes Association. Standards of medical care in diabetes–2014. Diabetes Care. 2014;37 Suppl 1:S14-80.
2. Eli Lilly . Humulin N [package insert] 2013.
3. Novo Nordisk. Levemir [package insert] 2013.
4. Novo Nordisk. Novolog [package insert] 2014.
5. Sanofi-Aventis. Apidra [package insert] 2014.
6. Heise T, Nosek L, Rønn BB, et al. Lower within-subject variability of insulin detemir in comparison to nph insulin and insulin glargine in people with type 1 diabetes. Diabetes. 2004;53:1614-20.
7. Brunner GA, Sendhofer G, Wutte A, et al. Pharmacokinetic and pharmacodynamic properties of long-acting insulin analogue nn304 in comparison to nph insulin in humans. Exp Clin Endocrinol Diabetes. 2000;108:100-5.
8. American Diabetes Association . Insulin administration. Diabetes Care. 2004;27 Suppl 1:S106-9.
9. Goldman-Levine JD, Lee KW. Insulin detemir–a new basal insulin analog. Ann Pharmacother. 2005;39:502-7.
10. Eli Lilly . Humulin R [package insert] 2013.
11. Novo Nordisk. Novolin R [package insert] 2013.
12. Ratner R, Wynne A, Nakhle S, Brusco O, Vlajnic A, Rendell M. Influence of preprandial vs. postprandial insulin glulisine on weight and glycaemic control in patients initiating basalbolus regimen for type 2 diabetes: a multicenter, randomized, parallel, open-label study (nct00135096). Diabetes Obes Metab. 2011;13:1142-8.
13. Meyer C, Boron A, Plummer E, Voltchenok M, Vedda R. Glulisine versus human regular insulin in combination with glargine in noncritically ill hospitalized patients with type 2 diabetes: a randomized double-blind study. Diabetes Care. 2010;33:2496-501.
14. Umpierrez GE, Hor T, Smiley D, et al. Comparison of inpatient insulin regimens with detemir plus aspart versus neutral protamine hagedorn plus regular in medical patients with type 2 diabetes. J Clin Endocrinol Metab. 2009;94:564-9.
15. Sanofi . Lantus [package insert] 2013.