(A) Freestyle Libre - SUDES Fellows.pptx

FreeStyle Libre

1. Diabetes Technology Flash Glucose monitoring (Free Style Libre ) Dr.Altayeb Abdalaziz MBBS (Hons), MRCP(UK), MRCP(London) Queen Elizabeth hospital Fri 25 .06.2021

2. 01 Technology progress over the years 02 TiR & the new diabetes languauge 03 What is FSL and what is the evidence 04 How to interpret the data 05 Practical tips 06 Questions

3. What we have covered in previous sessions: Freestyle Libre 02 CGM Overview 01 Insulin pump 03 Practice Practice Practice practice 04 Insulin

4. Glucose testing over the years:

5. The  Ames Reflectance Meter  was the first blood glucose meter developed by Anton Herbert “Tom” Clemens on September 14, 1971. The meter weighed about 1.2 Kg and sold for about $500. It was initially marketed to physician's offices, not patients, One man with diabetes ,   Richard K. Bernstein , managed to buy one because his wife was a physician and his whole reason [for going to medical school] was ‘’because I couldn't get published’’. The first published paper about SMBG was by a doctor in Pittsburgh, Pennsylvania [   Danowski TS and Sunder JH.  Jet injections of insulin during self-monitoring of blood glucose. Diabetes Care 1:27-33, 1978.] The first glucometer:

6. Glucose testing over the years: More reliable, precise dose delivery (0.05u compared to 0.5u), automatic dose calculation & accurate boluses.

7. Evolution of glucometers:

8. Healthcare Across Borders - September 2003 Convergence Toward Automation HCP Self Management Automation 1922 Insulin & syringes 1979 Pumps 1983 Pens Connectivity 1926 Clinic Monitoring 1971 Home Monitors Data Management Advice/Feedback Open Loop Closed Loop We are here Adapted courtesy Roche/Disetronic Continuous Monitors There is Insulin delivery Glucose monitoring

9. Why do need to achieve a good control? The United Kingdom Prospective Diabetes Study ( UKPDS ) and the Diabetes Chronic Complications Trial ( DCCT ) are two landmark trials that convincingly demonstrated that tight glycemic control has beneficial effects on microvascular end points. These studies also revealed a “ legacy effect” which is a sustained benefit with respect to cardiovascular disease outcomes seen long after the conclusion of the trial. However this is associated with significant increased risk of hypoglycemia . FreeStyle Libre (FSL) is a flash glucose monitoring ( FGM ) system which provides on-demand near continuous glucose levels and changes in the interstitial fluid compartment and has been shown to reduce time spent in hypoglycemia.

10. Healthcare Across Borders - September 2003 Why We Do It Better Control Reduces Complications 55.0 29.8 23.9 5.1 13.4 13.0 7.9 16.4 5.0 2.5 10 20 30 40 50 60 Retinopathy Progression Laser Rx 1 Micro- albuminuria 2 Albuminuria 2 Clinical Neuropathy 3 Conventional Intensive 76% Risk Reduction 59% Risk Reduction 39% Risk Reduction 54% Risk Reduction 64% Risk Reduction Cumulative Incidence (%) DCCT Research Group, Ophthalmology. 1995;102:647-661 DCCT Research Group, Kidney Int. 1995;47:1703-1720 DCCT Research Group. Ann Intern Med. 1995;122:561-568.

11. Healthcare Across Borders - September 2003 Less Damage With Lower A1cs Better

12. Diabetes control is more than just HbA1c:

13. Variability & time in range are the new language of diabetes care:

14. The width of the area shaded dark blue represents usual variability. The width of the area shaded light blue represents occasional variability. The area under the median line represents the same as the average. The estimated A1c is calculated from this. Smart devices should reduce glucose exposure and glucose variability How does variability differ from exposure?

15. Healthcare Across Borders - September 2003 Exposure And Variability One day’s tests every 30-60 min with usual meals and insulin Exposure or Average Variability or Swing

16. What does variability look like on the AGP? Non-diabetic Good control

17. Healthcare Across Borders - September 2003 Exposure And Variability Are Different Glucose variability (SD) and A1cs in two individuals: Top : A1c = 6.6% SD = 20 mg/dl (1.1 mmol ) Bottom : A1c = 6.7% SD = 61 mg/dl (3.4 mmol ) R. Derr et al: Diabetes Care, 26: 2728-33, 2003

18. Healthcare Across Borders - September 2003 Exposure And Variability Are Unrelated These 256 consecutive meter downloads found no relation between glucose exposure (A1c) and glucose variability (SD) SD varied from very stable at 8.1 mg/dl (0.4 mmol) to very unstable at 152.5 mg/dl (8.4 mmol) Average SD was 63.3 mg/dl (3.5 mmol) Take home: Keep SD below 65 Comparison of A1c and meter downloads from 256 subjects at Johns Hopkins R. Derr et al: Diabetes Care, 26: 2728-33, 2003

19. Consequences of wide glucose variability:

20. TIR target recommendation for mot patients:

21. What about pregnancy? Fingerstick capillary blood glucose (CBG) targets (NICE 2015): Fasting CBG <5.3 mmol /l. 1 hour after meals CBG <7.8 mmol /l 2 hours after meals CBG <6.4 mmol /l And to maintain CBG >4 mmol /l Continuous glucose monitoring (CGM) targets: Sensor glucose 3.5-7.8 mmol /l at least 70% of the time. Sensor glucose >7.8 mmol /l less than 25% of the time. Sensor glucose <3.5 mmol /l less than 4% of the time. -including sensor glucose <3.0 mmol /L less than 1% of the time.

22. Flash glucose monitoring system (FSL):

23. What is FSL ? Flash glucose monitoring system which measures glucose level in interstitial fluid , r esults can be obtained through clothing. Glucose levels lag about 5-10 minutes behind blood glucose levels. Stores a glucose reading in 15 minutes blocks, holds only the last 8 hours data and has trend arrows. The sensor lasts up to 14 days then need to be replaced . Libre2 has more accuracy and has an alarm features added to it. LibreLink app on smartphones sync automatically to LibreView to connect with HCP, family … etc. On Drug Tariff from Nov 2017

24. CGM/FSL- How does it work? Interstitial glucose measurements in intervals of 1 to 5 minutes. Comprehensive assessment of glycemic control in real time. Alerts and trend arrows for glucose trends allows influences treatment decisions. Continue to become easier to use, more accurate, and more access.

25. Plasma/sensor lag effect: Lag times are longest when the glucose is changing direction from down to up or up to down. (mimicking the train car effect)

26. FSL getting started tutorial:

27. Get familiar with the FSL device:

28. What does the evidence shows:

29. Our own experience with FSL:

30. What dose our real-world data show: Objectives : To evaluate the efficacy and impact of FSL on glycemic control and hypoglycemia in adults with Type 1 diabetes. Method : Patients with type 1 diabetes under CDDFT care with either: poor glycaemic control, recurrent hypoglycaemia, pregnancy and/or excessive capillary glucose testing were offered a trial of FSL for a period of 12 months and their control was monitored using the FSL downloads. Data was expressed as average ±SD and difference was assessed using paired student T-test.

31. Our local data analysis results: 115 patients with type 1 diabetes (55% female) were followed for one year (age 45 ± 13 years). Baseline HbA1c was 71 ± 19mmol/ mol which dropped to an average of 61.7 ± 13mmol/ mol in three months’ time and remained stable at an average of 63.6 ± 17 mmol / mol and 61.2 ± 10 mmol / mol in 9 and 12 months respectively ( p<0.05 ) without a noticeable increase in their hypoglycaemia. There was a sustainable reduction (9± SD mmol / mol ) in HbA1c at 12 months (Figures 1).

32. Results:

33. What did our patients say about it: My fingers are still thanking me for this wonderful new painless scanning ! They can also test my levels at nights without waking me up!

34. Our onclusion : Our data revealed a rapid improvement in HbA1c which was sustained over the 12 months’ period of the study among patients who used the FSL reflecting the benefit of technology in improving the patients’ outcome. Hypoglycaemic episodes appears also to be reduced ( still analysing the data to assess whether this is statistically significant). Most of the patients expressed their satisfaction about the FSL.

35. What is the cost of FSL ? FreeStyle Libre was added to the Drug Tariff on 01/11/17. Cost = £50 per sensor , which last 2 weeks. FreeStyle Libre is available to buy on line and some patients have chosen to self fund. Water-resistant, Can be worn while bathing, showering, swimming (up to 1 meter , 30 min), and exercising. There are currently NICE recommendations for this system. Now accepted by the DVLA.

36. Cost calculation for a flash glucose monitoring system for UK adults with type 1 diabetes mellitus receiving intensive insulin treatment: The flash monitoring system has a modest impact on glucose monitoring costs for the UK NHS for patients with T1DM using intensive insulin. For people requiring frequent tests, flash monitoring may be cost saving , especially when taking into account potential reductions in the rate of severe hypoglycaemia . Diabetes Research and Clinical Practice , Volume 138 , April 2018, Pages 193-20

37. Who should receive it?

38. FGM -Who is eligible? The Regional Medicines Optimization Committee (RMOC)that supports the use of flash in people with : T1D who undertake intensive monitoring (>8 times) daily. Those who fit the current NICE criteria for insulin pump therapy (HbA1c >8.5%) or disabling hypoglycemia (NICE TA151 ). Those who have recently developed impaired awareness of hypoglycemia. If frequent (>2/year) admission with diabetic ketoacidosis or hypoglycemia. Those who require third-party assistance to carry out recommended monitoring . https :// www.sps.nhs.uk/articles/regional medicines optimisation committee freestyle libre position statement/

39. 1. People with Type 1 diabetes OR with any form of diabetes on hemodialysis and on insulin treatment who, in either of the above, are clinically indicated as requiring intensive, as demonstrated on a meter download/review over the past 3 months OR with diabetes monitoring >8 times daily associated with cystic fibrosis on insulin treatment . 2. Pregnant women with Type 1 Diabetes - 12 months in total inclusive of post-delivery period. 3.People with Type 1 diabetes unable to routinely self-monitor blood glucose due to disability who require carers to help with glucose monitoring and insulin management. 4. People with Type 1 diabetes for whom the specialist diabetes MDT determines have occupational (e.g. working in insufficiently hygienic conditions to safely facilitate finger-prick testing) or psychosocial circumstances that warrant a 6-month trial of Libre with appropriate adjunct support. NHSE Criteria for Flash Glucose Monitoring Funding:-

40. 5 . Previous self-funders of Flash Glucose Monitors with Type 1 diabetes where those with clinical responsibility for their diabetes care are satisfied that their clinical history suggests that they would have satisfied one or more of these criteria prior to them commencing use of Flash Glucose Monitoring had these criteria been in place prior to April 2019 AND has shown improvement in HbA1c since self-funding. 6. For those with Type 1 diabetes and recurrent severe hypoglycemia or impaired awareness of hypoglycemia, NICE suggests that Continuous Glucose Monitoring with an alarm is the standard. Other evidence-based alternatives with NICE guidance or NICE TA support are pump therapy , psychological support, structured education, islet transplantation and whole pancreas transplantation . However, if the person with diabetes and their clinician consider that a Flash Glucose Monitoring system would be more appropriate for the individual’s specific situation, then this can be considered . 7 . People with Type 1 diabetes or insulin treated Type 2 diabetes who are living with a learning disability and recorded on their GP Learning Disability register. NHSE Criteria for Flash Glucose Monitoring Funding:-

41. 1. Education on Flash Glucose Monitoring has been provided (online or in person). 2. Agree to scan glucose levels no less than 8 times per day and use the sensor >70% of the time. 3. Agree to regular reviews with the local clinical team. 4. Previous attendance, or due consideration given to future attendance, at a Type 1 diabetes structured education programme (DAFNE or equivalent if available locally). Other requirements:

42. Ambulatory Glucose Profile (AGP):One Report to Rule Them All Learning to read the CGM reports:

43. As much of the blue shape as possible should fit inside the ”target range Box between 4 and 10mmol/L This means there can’t be either too much variability or instability.

44. Knowing the direction of change allows the user to make more informed decision about action to take prospectively rather than retrospectively. What do the arrows mean?

45. Insulin on Board (IOB): knowing which insulin is working will help avoid problematic blood glucose levels and reduce variability. Adequate BI Too much BI Too little BI Too much QA Correction after low

46. FSL-Benefits of the arrows:

47. Dose calculations are designed for pre-meal glucose levels. 1 -Hour glucose tells you about the timing of the insulin –did you take it early enough (BM rise by an average of 8-10mmol/l if you take insulin very close to the meal compared to only 3-5mmol/l if you take insulin 20minute pre-meal). +2-hour glucose tells you more about if you did take enough ( and if too much, is a common time to hypo) or if you need to take a correction dose. You should think about scanning between 2-3 hours post meal –that is the time when you may want to make a decision around carbs or insulin based on the results . Best time for scanning:

48. Postprandial Glucose bolus at (- 20/0/+20 )mins:

49. Understand the post meal change:

50. So interpret numbers in the context of its trend:

51. 1 ½ hour after breakfast glucose is now 18.1 and has just stopped rising What should you do? Correction dose? Wait and see? Example of meal effect on blood sugar: 4 hours post meal glucose is back in range

52. Adjusting for arrows: Consider Anticipated Glucose In 30 Minutes (assumes steady ROC * )

53. Adjusting bolus dose based on the arrows:

54. Adjusting bolus dose based on the arrows:

55. Adjusting bolus dose based on the arrows:

56. Examples for dose correction based on the rrows :

57. Examples for dose correction based on the rrows :

58. As you can see they all give slightly different results, and none of these are an exact science. Differences are a little larger for larger meals and those who are less insulin sensitive. For simplicity, we advise using the ISF (+ 0.5 or + 1.0) method. So which method to use?

59. Suggested approach to Libre view: 2 . Can you see any hypo Get rid of hypo first 1. Check the targets ,TIR & variability 5. Make the change putting in mind the IOB Assess + readjust 4. What are behaviour surrounding that time Exercise, diet, ICR, injection time/ techique 3. Look at the AGP first then individual days Identify single area for improvement

60. Case 1: 25 year old male T1DM for last 10 years on Lantus 20 units nocte and NR 1:10g CHO with every meal. How would you interpret this report? Any area for improvement? What are you going to tell him? Practice scenarios:

61. Case 2: 46 year old lady T1DM for last 10 years on Lantus 20 units nocte and NR 1:10g CHO with every meal. How would you interpret this report? Any area for improvement? What are you going to tell him? Scenarios practice:

62. Case 3: 62 year old male T1DM for last 10 years on Lantus 20 units nocte and NR 4+4+4 How would you interpret this report? Any area for improvement? What are you going to tell him? Scenarios practice:

63. Eeeeeeh, I See ….

64. Case 4: 56 year old lady T1DM for last 10 years on Lantus 20 units nocte and NR 4+4+4 How would you interpret this report? Any area for improvement? What are you going to tell him? Scenarios practice:

65. End aim: Stop hypos first - Importance of avoiding extreme hyper-and dangerous hypoglycemia. Reducing variability and increasing TiR is often the first step to improving overall control. Improvement in time in range significantly reduced retinopathy and nephropathy. Measuring A1c alone provides no information on glucose variability.

66. How to read the glucose downloads: See how much of the time is CGM/sensor being worn ? Review CGM download together with the patient, explain what you are observing. Goal Setting: Focus on the biggest problem and address solutions. Glycemic Metrics –Estimated A1c, mean, glucose variability/SD, time in various ranges. Look at trends not just individual values ! Great if consistent trends show up on the AGP but if it doesn’t help, look at several of the individual days . Don’t over-react to data – Avoid frequent between meal corrections until pattern is clear.

67. Future expectations:

68. Now you are Libre expert, Well done !

69. Thanks! Do you have any questions ? [email protected] [email protected] [phone] Please keep this slide for attribution.