This site is intended for health professionals only

A modern approach to insulin therapy

Susan Chisholm
RGN BA PostGradCertPractEd CertDiabetes PrimaryCare
Diabetes Specialist Nurse
Diabetes Centre
Perth Royal Infirmary
Perth

Diabetes mellitus is one of the most common chronic conditions in the western world. It is associated with considerable morbidity and mortality due to complications that arise through poor glycaemic control. Intensive treatment regimens can significantly reduce the risks of developing complications. Some of the recommendations made by the National Diabetes Frameworks state that a more individualised, empowering approach to insulin therapy should be adopted.(1,2)
Insulin therapy was first introduced in the early 1920s by the famous pioneers Banting and Best. Over the years, researchers have struggled with limiting technology to try and create an insulin regimen that mimics the normal function of the pancreas. Interestingly, insulin delivery devices did not change from wide bore glass syringes and large needles to pen devices until the 1990s.(3)
Although insulin was hailed as a "cure" for diabetes in the 1920s, it has since become apparent that the development of insulin therapy and delivery devices did little to reduce the complications associated with diabetes.(4) The advent of new analogue insulin, developments in oral therapy and novel insulin delivery devices have expanded the "diabetes toolkit" of treatments. This toolkit could potentially meet the challenge of developing an individualised, empowering approach to insulin therapy that will also reduce complications associated with diabetes.(3,4)

Modern approaches
The new analogue insulin has been developed to closely mimic the function of the normal pancreas. For comparisons with the older style of insulin please refer to Table 1.(3)

[[nip36_30_table1]]

Highlighted in Table 2 are a variety of more modern insulin delivery devices.(5)

[[nip36_32_table2]]

Insulin therapy is a life-sustaining treatment for individuals with type 1 diabetes. Alternatively, whether insulin therapy is effective in treating individuals with type 2 diabetes has been widely debated.(8)
Insulin therapy for those with type 2 diabetes should include a weight control strategy, as intensive insulin therapy can induce weight gain due to the anabolic effect of high doses of insulin, increased appetite and increased freedom to eat. Insulin-induced weight gain can be a problem for many, in particular it will be a problem for those who are overweight or obese before commencing insulin therapy.
Interventions promoting dietary changes and increasing activity should be initiated early in the management of type 2 diabetes and continued throughout the duration of all treatment regimens. Positive lifestyle interventions can delay the need for insulin therapy for those with type 2 diabetes by improving the effect of the individual's own insulin or reducing the effects of insulin resistance.(8)
One of the most commonly used strategies to limit insulin-induced weight gain is to combine metformin with insulin. Metformin is an oral preparation that reduces glucose processing in the liver and speeds up the utilisation of glucose. Loss of appetite and gastrointestinal discomfort, caused by the "speeding up" process, have been identified as the main reasons why metformin successfully limits weight gain.
Some studies have considered other weight loss medications and treatments such as bariatric surgery (gastric bypass surgery) that could be potentially more successful in providing a longer-term solution to insulin resistance in type 2 diabetes. While bariatric surgery has proved successful for those severely obese (body mass index [BMI] > 40), further research is required for those with a lesser degree of obesity.(8)
Even though new modern approaches to insulin therapy and treatment regimens are available for people with type 1 and type 2 diabetes, tight glycaemic control seems to be an elusive target for many. Personal barriers to insulin therapy have been identified that explain why some of these new approaches have been unsuccessful.(4,5)
Personal barriers to insulin therapy include:

  • Fear of needles or multiple injections.
  • Competency or dose adjustment.
  • Hypoglycaemia.
  • Weight gain.
  • Personal failure or denial.
  • Frequent monitoring.

Intensive group education and peer support can alleviate some patient barriers to insulin therapy. Collaborative empowerment strategies are recommended to facilitate the individual's ability to adapt and integrate diabetes into their life in a positive manner. The individual's perspective of diabetes should be considered when tailoring insulin therapy and delivery devices to meet their needs.(9) Table 3 highlights the more modern educational approach to insulin initiation.(10)

[[nip36_32_table3]]

Approaching insulin therapy
The following two case scenarios represent realistic challenges when considering an individualised, empowering approach to insulin therapy.

Case one: Mrs Green
Situation: Mrs Green has type 2 diabetes, Hba1c 10%. She has osmotic symptoms and has been taking glicazide 160 mg twice daily for the past year, but is intolerant of metformin. Her BMI is 38 and she has evidence of cardiovascular disease.
Background: She is 50 years old, and has not coped well since her husband died a year ago, but has recently started meeting up with old friends again

Case two: Alec
Situation: Alec has type 1 diabetes, Hba1c 14%. He fears hypoglycaemia at work, but doesn't always take his morning dose of mixed insulin, as he hates needles.
Background: Alec is 18 years old and has had diabetes for five years. He left school at 16 and now works as an apprentice plumber. He lived with his girlfriend until he discovered that she was pregnant with his best friend's baby. He has since moved back home with his parents.

What treatment regimens could you consider?
Below are some examples of an individualised approach to insulin therapy. Arguably, an individualised, empowering approach may not correlate with national guidelines.1,2,6,7

Case one: Mrs Green

  • Twice-daily premixed insulin. This has been the most common firstline treatment. It will alleviate symptoms quickly but significant weight gain often occurs and therefore it is not necessarily the best treatment option for this patient.
  • Once-daily long-acting analogue insulin with current and other oral hypoglycaemic agents plus lifestyle modification. This will alleviate symptoms and the patient may be motivated to lose weight and reduce insulin resistance.
  • Motivational interviewing and lifestyle coaching to instigate diet changes and increased activity. This may alleviate symptoms over time and if weight loss is achieved insulin resistance may be reduced.
  • Mrs Green may prefer gastric bypass surgery to avoid the need for insulin and injections.

Case two: Alec

  • Once-daily long-acting analogue using jet injector. This option is needle-free but the patient should be advised to take some quick-acting insulin with food.
  • Once-daily long-acting analogue with inhaled insulin at meals. This option is flexible but the patient may be more likely to take quick-acting insulin.
  • Attend an intensive insulin management course. This should encourage the patient to enhance self-management skills).
  • Alec may feel that the best option for him is an insulin pump (flexible, tight control, reduced hypoglycaemia).


Conclusion

Even though there have been advances in insulin therapy, tight glycaemic control seems to be an elusive target for many. Variable lifestyles, as illustrated in both case studies, can contribute to the challenge of developing an individualised approach to insulin therapy that will assist in reducing complications associated with diabetes.
The ever-expanding "diabetes toolkit" can enable the healthcare professional to tailor insulin therapies and delivery devices to support the individual's efforts in optimising their glycaemic control. The greatest test for the healthcare professional is designing a treatment regimen that complies with the individual's own perspective of diabetes, not the other way around.

[[nip36_34_pp]]

References

  1. Scottish Executive. Scottish diabetes framework action plan. Edinburgh: Scottish Executive Publications; 2006.
  2. Hall G. The NSF and GMS: a marriage made in heaven? Diabetes Primary Care, 2005;7 Suppl:33.
  3. Garg S, Ulrich H. Achieving goal glycosylated hemoglobin levels in type 2 diabetes mellitus: practical strategies for success with insulin therapy. Insulin 2006;1:109-21.
  4. Verge D. Innovative solutions for diabetes therapy. Diabetes Res Clin Pract 2006;74:148-51.
  5. Flood T. Advances in insulin delivery systems and devices: beyond the vial and syringe. Insulin 2006;1: 99-108.
  6. NICE. Inhaled insulin for the treatment of diabetes (types 1 and 2). NICE technology appraisal guidance 113. London: NICE; 2006.
  7. NICE. Continuous subcutaneous insulin infusion for diabetes. NICE technology appraisal guidance 57. London: NICE; 2003.
  8. Heller S. Weight gain during insulin therapy in patients with type 2 diabetes mellitus. Diabetes Res Clin Pract 2004;65:23-7.
  9. Samson J. Exploring young people's perceptions of living with type 1 diabetes. J Diabetes Nurs 2006;10:351-8.
  10. Wallymahmed M. Insulin therapy in the management of type 1 and type 2 diabetes. Nurs Stand 2006;21:50-6.

Resources
Diabetes UK
W: www.diabetes.org.uk

European Association for the Study of Diabetes
W: www.easd.org

Tayside Diabetes Network
W: www.diabetes-healthnet.ac.uk
Forthcoming events in Scotland
Health Professional Conference
13 November 2007; Dunblane Hydro, Dunblane

Diabetes UK - annual professional conference
1-3 March 2008; SECC, Glasgow