Insulin Pumps: A Better “Shot”at Diabetes Care

1. Insulin Pumps: A Better “Shot”at Diabetes Care The 32nd Annual School Health Conference Thursday, May 20, 2010

2. Overview • Epidemiology • Pathogenesis • Insulin Therapy • Importance of Control • Insulin Types/ Delivery Systems • Pump Basics • Pump Brands • Infusion Sets • Pump Candidates • Starting on a Pump • Hypoglycemia • Hyperglycemia • Case Scenarios

3. Type 1 Diabetes Mellitus • Previously referred to as insulin-dependent or juvenile diabetes • Polygenic, multifactorial, autoimmune disease • Most commonly occurs in the young

4. Epidemiology • In 2004, 3 million Americans were estimated to have type 1 diabetes. • There is a 3% increase in incidence per year. • Approximately 1 in every 400-500 children has type 1 Diabetes. • Diabetes is second most common chronic disease in childhood after asthma.

5. Epidemiology • Peak ages at onset: 5-7 and early puberty • 30% of cases onset 18 - 40 years of age • There is a genetic association in regards to the risk of developing diabetes.

6. Risk for Type 1 DiabetesBy Family Member with Diabetes

7. Pathogenesis of T1DM • T-cell mediated process directed at pancreatic  cell. • Pancreatic islet cell destruction results in absence of insulin. • Absence of insulin causes chronic hyperglycemia.

8. Natural History of Type 1 Diabetes Genetic Predisposition Immunological Abnormalities Beta-cell Mass (% max) Normal insulin release Impaired insulin release 100 Overt diabetes 50 “Honeymoon” period 0 Birth Time (years)

9. What does insulin do? • Insulin is a hormone secreted by the -cells of the pancreas in response to rising glucose levels. • Insulin is a “key” that allows peripheral tissues to open and allow glucose to enter.

10. What does insulin do?

11. Absence of Insulin • Absence of insulin causes the body to act in fasting state, despite being fed. • Serum glucose cannot be used by peripheral tissues because of dependence on insulin. • Stimulation of hepatic glycogenolysis and gluconeogenesis cause further hyperglycemia. • All of the above cause serum glucose levels to exceed the renal threshold (180 mg/dl) and glucose is spilled into the urine.

12. Glycemic Controlin Type 1 Diabetes

13. Changes in Diabetes Management The Effect of Intensive Treatment of Diabetes on the Development and Progression of Long Term Complications in Insulin Dependent Diabetes Mellitus The Diabetes Control and Complications Trial Research Group NEJM 1993 Sep 30;329(14):977-86.

14. Diabetes Control and Complications Trial (DCCT) 10.0 9.5 9.0 8.5 Hemoglobin Conventional 8.0 Intensive A1c 7.5 7.0 6.5 6.0 Adults Adolescents

15. Risks & Benefits of Intensive Diabetes Therapy (DCCT) • Decreased Risk (%) • Progressive retinopathy 60 • Microalbuminuria 40 • Neuropathy 60 • Increased Risk (%) • Severe hypoglycemia 300

16. Glycemic Control in Pediatrics • Controversy remains about the level of glycemic control that should be targeted for children despite the findings of fewer complications with better control. • Concerns exists given the high risk of hypoglycemia and what hypoglycemia can do to the developing brain.

17. Glycemic Control in Pediatrics • Consensus Statement from the American Diabetes Association targets the following goals: Diabetes Care 2009; 32: S13-S62.

18. How is glycemic control achieved? Insulin Therapy

19. 2 3 4 5 6 7 8 9 12 13 14 15 16 17 18 19 20 21 22 23 24 0 1 10 11 Action Profiles of Insulins Aspart, glulisine, lispro 4–5 hours Regular 6–8 hours Plasma insulin levels NPH 12–16 hours Detemir ~14 hours Ultralente 18–20 hours Glargine ~24 hours Hours Burge MR, Schade DS. Endocrinol Metab Clin North Am. 1997;26:575-598; Barlocco D. Curr Opin Invest Drugs. 2003;4:1240-1244; Danne T et al. Diabetes Care. 2003;26:3087-3092

20. How can insulin be delivered? • Draw up from vial and administer with syringe • Insulin pens • Insulin pumps

21. Insulin via Syringe • Insulin is drawn from a vial into a 28-31 gauge insulin syringe • Used for all patients who are newly diagnosed with diabetes as insulin doses are being adjusted daily

22. Doses are “dialed up” Administer like insulin injection via syringe and hold down back of pen Benefits: Faster than syringe injections Drawbacks: Less fine tuning of doses due to increments and pre-mixed pens come in specified dosages (70/30 or 75/25) Insulin Pens

23. 0600 1800 0800 0600 1200 2400 3 Injections a day Aspart, glulisine, or lispro U/mL NPH at bedtime 100 NPH B L D 80 60 Normal pattern 40 20 Time of day B=breakfast; L=lunch; D=dinner

24. 0600 1800 0800 0600 1200 2400 3 injections a day Aspart, glulisine, or lispro U/mL 100 Levemir B L D 80 NPH 60 Normal pattern 40 20 Time of day B=breakfast; L=lunch; D=dinner

25. 0600 1800 0800 0600 1200 2400 4 + Injections a day Aspart, glulisine, or lispro U/mL 100 Glargine or Levemir B L D 80 60 Normal pattern 40 20 Time of day B=breakfast; L=lunch; D=dinner

26. First Outcome Study of Pumps in Pediatrics Reduction to normal of plasma glucose in juvenile diabetes by subcutaneous administration of insulin with a portable infusion pump WV Tamborlane, RS Sherwin, M Genel, and P Felig NEJM 1979; 300:573-8

27. The Development of the Insulin Pump Autosyringe AS2C Used 50mL syringe Had only one basal rate No memory Slightly noticeable when worn

28. NEJM 1979; 300:573-8

29. Barriers to Pump Use Pre-DCCT • SIZE • Technical Limitations of early pumps • Fear of hypoglycemia • Fear of weight gain • Psychosocial Issues • Lack of commitment to intensive therapy • Patients • Parents • PHYSICIANS

30. Barriers to Pump Use Pre-DCCT Many pediatric endocrinologists were reluctant to use pumps to treat patients with type 1 diabetes. A lack of data about pump use in children was often cited.

31. Therefore, studies on the benefits of pump therapy in pediatric patients were completed.

32. p=.89 (NS) p = .03 Changes in HbA1c Levels 8.5 8 A1c (%) 7.5 Pump 7 MDI 6.5 Baseline 4 wks 8 wks 12 wks 16 wks

33. Average Pre-Meal Glucose Levels 230 P<0.001 210 MDI 190 CSII 170 150 130 110 90 Breakfast Lunch Dinner Bedtime

34. Improved Control With CSII DCCT Adol HbA1c Age Ahern, et al. Pediatric Diabetes 2002

35. Reduced Risk of Severe Hypoglycemia DCCT Adol 40 35 30 seizure or coma events per 100 pt yrs. 25 20 15 10 5 0 12 Months Pre-Pump 12 Months Pump Rx

36. Glycemic control Pre and post pump therapy in children <7 years Pediatrics 2004;114:1601-1605

37. Improvement on Pumps Pediatric Diabetes 2006; 7 (Suppl 4) 15-19.

38. Change in Hemoglobin A1c Pediatric Diabetes 2006; 7 (Suppl. 4): 20-24.

39. Advances to Pumps • Smaller size (roughly the size of a pager) • Multiple basal rates • Temporary basal rates • Direct glucose entry from meter or continuous monitor • Able to check history • Reminders and alerts • Ability to disconnect infusion sets • Bolus wizard availability • Preprogrammed carbohydrate ratios and correction factors • Glucose targets • Duration of insulin action

40. Pump Basics

41. Pump Basics • External, programmable pump • Continuously delivers insulin via indwelling subcutaneous catheter • Requires input from wearer • About the size of a cell phone/pager • Operates on a AAA battery • Hold up to 300 units of insulin

42. Pump Basics: Insulin Delivery • Uses only Rapid Acting insulin (NovoLog®, Humalog®, Apidra®) • Patient no longer uses long acting insulin • Insulin delivered in 2 ways • Basal • Bolus

43. Pump Basics: Basal Rates • Continuous “background” level of insulin • Basal rates are programmed in units/hr • Pump breaks down hourly insulin delivery rate into drips delivered every few minutes

44. Pump Basics: Basal Rates Background insulin released slowly throughout the day. Lantus or Levemir Pump 2:00 7:00 12:00 16:00 20:00 24:00 7:00 Time Basal insulin delivery from a pump provides a better and faster match for life’s needs

45. Pump Basics: Temporary Basal Rate • Temporary adjustment to basal pattern • Set in response to change in usual activity • Exercise (lower the usual basal pattern) • Sick Day (increase the usual basal pattern) • Programmed by • Duration • % of Basal • Example: Temporary rate at 200% for 3 hrs • Pump automatically returns to usual basal pattern at completion of temporary rate

46. Pump Basics: Bolus Insulin • “Burst” of insulin programmed at the time it needs to be delivered. • 2 Types of Boluses • Correction Bolus • Meal Bolus

47. Correction Bolus • Dose of insulin given to “fix” a BG that is outside of target range • Dose is based on: • Correction Factor (pre-programmed in the pump) • Target BG (pre-programmed in the pump) • Actual BG (entered into the pump by the user) • Corrections should not be given more frequently than every 2 hours • Giving corrections more frequently risks “stacking” the corrections • “Stacking” causes low BG levels 4-6 hours later

48. How to Calculate a Correction Dose 1. Need: Correction Factor, Target BG, and Actual BG 2. Subtract Target BG from Actual BG 3. Divide Answer from # 2(above) by Correction Factor Example: Correction Factor – 1 unit per 125 mg/dL Target BG – 100 mg/dL Actual BG – 295 mg/dL 295-100 = 195/125 = 1.6units

49. Meal Bolus • Dose of insulin given to “cover” the carbs in a meal • Dose is based on • Total grams of carbohydrates in meal • Insulin to Carbohydrate ratio (I/C) • Designed to bring BG back to where it started • Pre-meal BG is 235 mg/dL • 2hr PP BG will be around 235mg/dL • Bolus must be givenbeforemeal to limit after meal increase in BG levels

50. How to Calculate a Meal Bolus • Need: insulin to carb ratio, total # carbs in the meal • Divide total # Carbs by Insulin to carb ratio Example: Total # carbs = 95 grams I/C – 1 unit per 12 grams 95/12 = 7.9 units