Alice Y.Y. Cheng, MD FRCPC Peter Lin, MD CCFP Insulin Initiation and Titration for Family Physicians: Case Study #1: William Alice Y.Y. Cheng, MD FRCPC Peter Lin, MD CCFP

Case Study #1: William Patient history and presentation 59-year-old male stockbroker Type 2 diabetes x 8 years Weight = 90 kg A1C = 7.9% He is on metformin, an insulin secretagogue and a TZD – he is at the maximum dose of all three oral agents You have been proposing that he start insulin during the past few visits in the last year, and he is now becoming more agreeable to the idea William is a 59-year-old male stockbroker. Given his career, his lifestyle and eating patterns may be erratic. William has had type 2 diabetes for 8 years. His weight is 90 kg, and his A1C is 7.9%. He is on metformin, an insulin secretagogue and a TZD – he is at the maximum dose of all three oral agents. His physician has been proposing that he start insulin during his past few appointments over the last year, and he is now becoming more agreeable to the idea.

William’s SMBG Logbook Breakfast Lunch Dinner Before After Bedtime Sunday 9.7 9.2 7.5 Monday 9.4 10.0 6.9 Tuesday 9.0 8.6 7.8 Wednesday 9.1 8.9 Thursday 8.8 8.5 William’s SMBG logbook is  shown on this slide. According to the Canadian Diabetes Association clinical practice guidelines, his target pre-meal blood glucose should be between 4.0 and 7.0 millimoles per litre.1 However, as shown above, William’s blood glucose readings are higher than target throughout the day, and are particularly high in the morning. Reference Canadian Diabetes Association Clinical Practice Guidelines Expert Committee. Canadian Diabetes Association clinical practice guidelines for the prevention and management of diabetes in Canada. Can J Diabetes. 2008;32(suppl 1):S1-S201.

Case Study #1: William (cont’d) Case review William has suboptimal glycemic control, according to the guidelines He is maxed out on oral agents He continues to have high BG levels, particularly in the morning What insulin regimen would you prescribe? Clearly, William has suboptimal glycemic control, according to the guidelines. He is maxed out on oral agents, but continues to have high BG levels, particularly in the morning. What insulin regimen would be appropriate for a clinician to prescribe?

Type 2 Diabetes: Insulin Categories Basal Basal plus bolus Pre-mixed twice daily Here are the three categories of insulins.

Case Study #1: William (cont’d) The easiest insulin to start would be basal insulin at bedtime, which has the advantage of a single injection – so it is easy to remember At this point, the TZD should be discontinued (to minimize risk of edema); however, the metformin and insulin secretagogue can both be continued Since William has predominantly high fasting blood glucose levels, the easiest insulin regimen to start would be basal insulin at bedtime, which has the advantage of a single daily injection. William’s TZD medication should be discontinued to minimize the risk of edema, but the metformin and insulin secretagogue should be continued.

CHOOSE AN INSULIN CATEGORY CHOOSE A BRAND DOSING SEE REVERSE FOR TIPS Using the Ontario College of Family Physicians Insulin Prescription Tool: The first step is to choose an insulin category; we have selected basal insulin. The next step is to choose an insulin brand. Finally, complete the dosing and titration information for the basal insulin selected.

The back side of the Ontario College of Family Physicians Insulin Prescription Tool describes how to initiate and titrate basal insulin.   William will likely require 50 units of basal insulin daily, given his weight. However, per the instructions, he should be started at a low dose of 10 units, and then William will titrate accordingly.

Basal Insulin Dosing and Titration 10 1 1 4.0–7.0

Case Study #1: William Three Years Later William had achieved an A1C <7.0% over the past few years with basal insulin plus metformin and an insulin secretagogue However, in the past 6 months his A1C has started to climb; it is now 7.5% He is currently on 50 units of basal insulin daily William was achieving an A1C of less than 7.0% over the past few years with basal insulin plus metformin plus a secretagogue. However, in the past 6 months his A1C has started to climb, and is now 7.5%. He is currently on 50 units of basal insulin daily.

William’s SMBG Logbook Breakfast Lunch Dinner Before After Bedtime Sunday 6.5 12.4 10.2 11.5 8.0 Monday 5.9 13.1 7.9 6.9 Tuesday 5.7 11.2 8.1 6.7 Wednesday 5.8 12.8 Thursday 5.5 8.5 William’s SMBG logbook is  shown on this slide. According to the Canadian Diabetes Association clinical practice guidelines, his target pre-meal blood glucose should be between 4.0 and 7.0 millimoles per litre.1 However, as shown above, William’s blood glucose readings are higher than target throughout the day, and are particularly high in the morning. Reference Canadian Diabetes Association Clinical Practice Guidelines Expert Committee. Canadian Diabetes Association clinical practice guidelines for the prevention and management of diabetes in Canada. Can J Diabetes. 2008;32(suppl 1):S1-S201. 11

CHOOSE AN INSULIN CATEGORY DOSING SEE REVERSE FOR TIPS CHOOSE A BRAND Select a bolus insulin. Usually, when adding another insulin, the clinician should select the same brand as the insulin the patient is already taking, to maintain consistency of the device. Next, complete the dosing and titration section for the bolus insulin chosen.

To determine the dosage of bolus insulin required, one could consult the back side of Ontario College of Family Physicians Insulin Prescription Tool. This section contains suggestions regarding how to dose insulin in a basal/bolus regimen. The formal method of calculating bolus insulin is suggested in the highlighted paragraph. Alternatively, a simpler way to add bolus insulin would be to add 10% of the basal dose; because William is at 50 units of basal insulin per day, that means he would start at 5 units of bolus insulin and increase it by one unit, until he reaches the target postprandial BG level of 5 to 10 mmol/L.

Bolus Insulin Dosing and Titration 5 Although at this time William only requires 5 units of bolus insulin at breakfast, this dose will be inadequate. He will need to titrate the dose up until he has reached postprandial glycemic targets. Over time, his postprandial glycemic control will also decline at lunch and dinner. At that time, he will need to add bolus insulin at those meals.

Bolus Insulin Dosing and Titration (cont’d) 10 10 10