Beyond Carbohydrate Counting:
What Else Matters?
Lorraine Anderson RD, CDE
Senior Clinical Manager, Animas Canada
2015 CWD Friends for Life Canada Conference – Niagara Falls
Disclosures
 Employee, Animas Canada.
 No other conflicts to disclose.
Objectives
 Discuss the importance of post-meal blood
glucose management and strategies for children
with type 1 diabetes.
 Review the latest literature regarding the roles of
carbohydrate, fat and protein in diabetes
management.
 Review strategies for practical application in day
to day practice.
Optimizing Post-meal Blood Glucose
 Why?
 How?
Optimizing Post-meal Blood Glucose
 Insulin:Carb (I:C) ratio
 Is it correct?
 Insulin Sensitivity Factor (ISF)/Correction Factor
 Does it work?
 Target BG/Duration of Insulin Action (pumps)
 Matching Insulin to Food (quantity and quality)
 Carb Counting
 Glycemic Index
 Fat and Protein Content
 Others?
 Timing, Exercise, Stress, Alcohol, More
Recommended Glycemic Targets for Children and
Adolescents with Type 1 Diabetes
* Postprandial monitoring is rarely done in young children except for those
on pump therapy for whom targets are not available.
Wherrett D et al. Can J Diabetes 37 (2013) S153-S162.
“It’s not just about the carbs”
Carbohydrate
 Greatest glycemic impact (time and magnitude)
 Carbohydrates don’t affect blood glucose equally
 Some of the potential variables effecting glycemic impact:
 Type and amount of CHO (starch, i.e. Basmati rice vs. short
grain)
 Fiber (soluble vs. insoluble)
 Sugar alcohols
 Physical form of the food
 Acidity
 Temperature
 Processing
 Cooking method – degree of gelatinization i.e. al dente pasta
Franz M. Carbohydrate and Diabetes: Is the Source or the Amount of More Importance? Current Diabetes Reports 2001. 1:177-186.
Carbohydrate Counting
 Beyond the Basics - 15g carbohydrate exchanges
Carbohydrate Counting Tools
How accurate are we?
 Smart CE et al. 102 children, 8-18 years and 110 caregivers
estimated CHO content of 17 standardized meals (8-90g)
 Most of the time (73%), we estimate to within 10-15 g.
 The larger the carb content of the meal, the greater the
inaccuracy in carb counting.
 Large meals are commonly underestimated whereas snacks
are commonly overestimated.
 Foods in non-standard servings sizes such as rice, pasta, cereal
and fruit most often inaccurately estimated.
 The longer the children had been carb counting, the greater
the percentage error – need ONGOING education.
Smart, CE et al. Diabet. Med 2009; 26: 279-285.
Carbohydrate Counting
 Two “inputs” when determining meal insulin
dose, both have risk of error
 Carb counting
 Meter accuracy
 And don’t forget adjustment for activity (↑↓),
alcohol, stress, high fat, high protein meals…
Smart, CE et al. Diabet. Med 2009; 26: 279-285.
Carbohydrate Counting
 Inaccurate carbohydrate counting is associated
with higher daily blood glucose variability.
 Though accuracy within 10-20g is NOT correlated
to higher A1C or significant postprandial glucose
excursion.
 Of all the “inputs” when determining meal insulin
dose, which has the greatest risk of error?
Smart, CE et al. Diabet. Med 2009; 26: 279-285.
Checking the I:C Ratio
 Fix the basal first
 Test the ratio when the pre-meal blood glucose is in target
 Try to do this when it has been at least 4 hours since the last
bolus
 No recent lows or exercise
 Eat a low-fat meal when you know the exact carb count
(i.e. Lean Cuisine, or use Salter scale)
 Test with ~ 1 g carbohydrate/kg body weight
 Test pre-meal, at 2 hr and 4 hr after meals
Checking Insulin:Carb Ratios
 What is an acceptable increase in BG at 2 hrs?
Insulin:Carbohydrate Ratio
 If set right, the I:C ratio should keep the BG rise
between 2.2 and 4.4 mmol/L, 2 hours later
 Should bring the BG back close to target at 4-5 hrs.
 If adjusting, do so by 1 or 2 g at a time
Walsh J. Pumping Insulin, 5th Ed. San Diego: Torrey Pines Press; 2012.
Evaluating Carb Bolus
14
too little
11
Test before meal,
every 1-2hr after and
before next meal.
8
dose just right
5.5
too much
meal
1 hour
2 hours
3 hours
4 hours
Adapted - John Walsh
Checking the Insulin Sensitivity Factor (ISF)
 When a correction bolus is injected/programmed,
how quickly should the BG return to target?
Checking the Insulin Sensitivity Factor (ISF)
 BG should return to target 4-5 hours LATER
 Should not cause hypoglycemia afterwards
Walsh J. Pumping Insulin, 5th Ed. San Diego: Torrey Pines Press; 2012.
Matching Insulin to Food
 The carbohydrate quantity causes the rise in
blood glucose after a meal and determines the
bolus size.
 The carbohydrate quality affects the rate at
which blood glucose rises and determines the
type of bolus to be used.
Evelyne Pytka 2008
Types of Boluses
normal/standard bolus
extended or square wave bolus
combination or dual-wave bolus
Advanced Bolus Features
 Normal bolus
 Entire bolus delivered immediately
 Extended bolus
 Bolus delivered over an extended period of time
 Combination bolus
 Portion of bolus is delivered immediately and portion is
extended over time
 Bolus mimics physiological insulin delivery – “first phase
and second phase delivery”
Why Use a Combination Bolus?
 Prevents early post meal hypoglycemia (from insulin
peaking before blood glucose rises)
 Prevents late post-meal high blood sugars (from not
having insulin to “cover” the late rise in glucose from
carbohydrate)
 The more rapidly-absorbed carbohydrate is
“covered” now, and the more slowly absorbed
carbohydrates are “covered” later
Why Combo Bolus?
 Unpredictable eaters, such as young children
 Gastroparesis (also pre-meal hyperglycemia slows
gastric emptying)
 Nutrient composition of meal
Ryan-Turek T. Variable Bolus Features on Insulin Pumps and Practical Applications for Use. On The Cutting Edge. 2005 26:4:16-18.
Wolpert H. Smart Pumping: A Practical Approach to Mastering the Insulin Pump. Virginia: ADA; 2002: 128.
Walsh J. Pumping Insulin, 5th Ed. San Diego: Torrey Pines Press; 2012.
Nutrient Composition of Meal
 “Slow carbs” – low GI, high fat
 “Fast carbs” – high GI, little or no fat
 High protein/High fat effect
 Independent and additive
Smart CE et al. Diabetes Care December 2013 vol. 36.12: 3897-3902.
How to Determine a Combination Bolus
Starting point:
 Split the bolus: 50% now, 50% over 3-5 hours (maybe longer?)
 Check blood glucose at 2, 4, and 6 hours after eating
 If “on the low side” at 2 hours, but “on the high side” 4-6
hours later, take less of the bolus up front, and spread more of
the bolus over time
 Adjust based on individual response
 What about injectors?
Adapted from Wolpert H, Smart Pumping, Alexandria VA: American Diabetes Association, 2003,p. 134.
Challenge your knowledge – Missed Boluses
Question 1:
True or False
 Missing the occasional meal bolus does not
impact A1C.
Missed meal boluses
 TAKING the bolus is important!!!
 “Forgetting” is very common – average of 2 missed meal boluses
per week among 7-20 year olds
Burdick, J. et al. Pediatrics Vol. 113, No. 3, March 2004, e221-224.
Forgot to Bolus?
 2 missed boluses per week  A1C increased 0.5%
 4 missed boluses per week  A1C increased 1.0%
 Most common reason: “forgetting”
Burdick, J. et al. Pediatrics Vol. 113, No. 3, March 2004, e221-224.
Missed meal boluses
 TAKING the bolus is important!!!
 “Forgetting” is very common – average of 2 missed meal boluses
per week among 7-20 year olds
 Reasons?
 Privacy/discretion
 Low pre-meal, decided to wait to bolus
 “Just forgot”
Burdick, J. et al. Pediatrics Vol. 113, No. 3, March 2004, e221-224.
Bottom Line
 MISSED MEAL DOSES ARE A MAJOR
REASON FOR SUBOPTIMAL
GLYCEMIC CONTROL
Challenge your knowledge – Bolus Timing
Question 2:
True or False
 Optimal glycemic control can be achieved when
meal-time insulin is given during or after the
meal.
Studies examining bolus timing

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Jovanovic et al. 2004 Clin Ther. Sep; 26(9):1492-7.
Cobry et al. 2010 Diab Tech Ther:12:173-7.
Scaramuzza et al. 2010 Diab Tech Ther;12:149-52.
De Palma et al. 2011 Diab Tech Ther;13(4):483-7
Danne et al. 2003 Diabetes Care;26:2359-64.
Ratner et al. 2011 Diabetes Obes Metab. 13(12): 1142-8.
Luijf et al. 2010 Diabetes Care; 33(10): 2152-5.
Ryan et al. 2008 Diabetes Care;31(8): 1485-90.
Liberty, I. et al. Practical Diabetes 2012; 29(3): 98–102.
When to bolus
 Cobry et al. 2010
 23 subjects aged 12-30, crossover study with
three treatment arms:
 Delivering a bolus 20 min prior to meal (PRE)
 Immediately before the meal
 20 minutes after the meal
Pre-meal vs start of meal vs post-meal bolusing
 20 minutes pre-meal
significantly better than start
of meal or 20 minutes after
Cobry E, et al. Diab Technol & Therapeutics, 2010
TiBoDi Study – Scaramuzza et al. 2010
 30 pts, T1 DM X 8.07 +/- 4.1 years, 6-20 years of age,
on pump therapy
 Compared glucose response to a standard meal
when bolus was given 15 min before, immediately
before or immediately after the meal.
 Results: No difference if the bolus is given 15 min or
immediately before meal HOWEVER, there is a
significant rise when the bolus is administered after
the meal, even if the BG was in the hypo range premeal.
TiBoDi Study – Scaramuzza et al. 2010
 If low pre-meal, correct the hypoglycemia, inject the
bolus, then eat.
 When bolus was given 15 min pre-meal, average post
meal levels never exceeded 7.8 mmol/L.
 15 min pre-meal bolus best option because it is
associated with smallest standard deviation (SD).
Bottom Line
 NO STUDIES FAVOUR POST-MEAL BOLUSING*
 If uncertain of the quantity to be eaten:
 give correction + grams carb likely to eat
 i.e. 20 g for child, 40 g for adolescent or adult
 The higher the pre-meal BG, the earlier the bolus should
be given.
 Timing is important.
Challenge your knowledge
Question 3:
True or False
 Although carbohydrate is the primary stimulus for
insulin secretion, it is not the only one.
Protein
 Many people eat double the recommended amounts
for protein
 How protein impacts blood glucose is controversial
 BG effect difficult to predict
 Up to 50-60% can be converted to glucose (TAG
theory)
 Common to see rise in BG 3-5 hours later, after
significantly larger than normal portions are
consumed.
Franz, M., ed. Diabetes Management Therapies: A Core Curriculum for Diabetes Education, 5h edition.
Chicago: American Association of Diabetes Educators, 2001.
*Bao et at. Am J Clin Nutr 2009;90:986-92.
Protein
 In people without diabetes:
 Protein ingestion stimulates the endogenous
production of both insulin and glucagon
 In people with type 1 diabetes:
 No endogenous insulin production
 Production of endogenous glucagon
 Protein causes a slow rise in BG; 3-5 hours after
eating
 Occurs after the peak of rapid-acting insulin analogs
 Cannot be included in meal bolus
Nutall FQ et al. 1984
Fat
 Effects on BG
 Delayed stomach emptying
 Decreased insulin sensitivity
 May last for several hours after eating
 Minimal fat actually converted to glucose (<10%)
 Individual’s response needs to be evaluated
Wolpert H. Smart Pumping: A Practical Approach to Mastering the Insulin Pump. Virginia: ADA; 2002: 128.
Funnell M., et al. Life with Diabetes: A Series of Teaching Outlines by the Michigan Diabetes
Research and Training Center. Alexandria: American Diabetes Association; 2004.
The ‘Warsaw School Program’ for dosing
mealtime insulin
 Bolusing for Fat and Protein
 100 kcal of fat/protein = 1 FPU = “10 g carb equivalent”
 Delivered as extended bolus




1 FPU is extended over 3 hours
2 FPU extended over 4 hours
3 FPU extended over 5 hours
> 3 FPU extended over 8 hours
 For example, a Hot Dog meal
 30 g of CHO, 16 g of PRO, 28 g of FAT
 How many FPU?
 I:C ratio is 1 unit per 10 g of CHO
Hot Dog Example
 Answer:
 30 g of CHO/10 g per unit = 3.0 units
Hot Dog Example
 Answer:
 30 g of CHO/10 g per unit = 3.0 units
 3 FPU ≈ “30 g carb equivalents” = 3.0 units
Hot Dog Example
 Answer:
 30 g of CHO/10 g per unit = 3.0 units
 3 FPU ≈ “30 g carb equivalents” = 3.0 units
 Therefore, 3 units as a normal bolus and 3 units
extended over 5 hours
RESULTS
 Pts with A1C < 7.5% (n=295) used this method more
often than those with A1C >7.5%
 19.5 +/- 18.4 times in 2 weeks vs 12.4 +/- 14.3 times in 2 weeks
 For patients using less than 14 S-W boluses during a
2-wk period, basal insulin requirement was 34.3+/15.8%, and respectively, in patients using more than
1 S-W bolus/d, the % basal insulin was 27.7+/10.2%.
 Also minimum of 6 boluses per day found to meet
A1C goal.
Wolpert et al (2013):
 7 adult patients with type 1 diabetes
 Compared 2x 18-h periods of closed-loop
glucose control after high fat (HF) and low fat
(LF) dinners
 Identical carbohydrate and protein in each
dinner
 10g fat in LF dinner and 60g fat in HF
dinner
 15 minute ‘meal priming bolus’ given before
each meal
Wolpert et al. Diabetes Care. April 2013; 36: 810-816.
Wolpert et al (2013):
 High fat dinner required more insulin than low fat
dinner (12.6 vs. 9.0 units) (ICR 1:9 vs 1:13)
 Still more hyperglycemia vs. low fat dinner
 No hypoglycemia
 These findings highlight limitations of carb
counting method.
Wolpert et al. Diabetes Care. April 2013; 36: 810-816.
Wolpert et al (2013):
 HF dinner increased mean insulin requirement
42%
 Marked inter-individual responses (-17% to
108%)  ?differences in FFA concentrations,
gastric emptying rates, glucagon, incretins
 Therefore need food records and must evaluate
based on a case by case basis.
 Dietary fat intake is an IMPORTANT consideration
for type 1’s striving for tight control.
Wolpert et al. Diabetes Care. April 2013; 36: 810-816.
Wolpert et al (2013) Conclusions:
 Adults with type 1 diabetes require more insulin
coverage for higher fat meals than for lower fat
meals with identical carbohydrate content
Wolpert et al. Diabetes Care. April 2013; 36: 810-816.
Fat and Protein ↑ Blood Glucose
 33 kids age 8-17 years
 4 test breakfasts – same amount of carb
1.
2.
3.
4.
Low fat, low protein
Low fat, high protein
High fat, low protein
High fat, high protein
Fat and Protein ↑ Blood Glucose
 What did they find?
Smart CE et al. Results Fat and Protein
 HP and HF significantly higher 180-300 min than
LP/LF meal.
 This late effect was increased and sustained with
HP/HF meal.
 HF meal alone reduced glycemic excursion first 90
minutes (likely due to delayed gastric emptying)
 However addition of protein prevented this
(suggesting that protein may have a protective
effect in early pp hypoglycemia)
Smart CE et al. Conclusions
 Cause of late, sustained hyperglycemia with HP/HF has been
postulated but is currently unknown.
 Protein may lead to delayed hyperglycemia by gluconeogenesis and ↑
glucagon secretion.
 Fat  FFA impair insulin sensitivity and enhancement of hepatic
glucose production, also delayed gastric emptying
 HP/HF (40 g pro, 35g fat) are commonly consumed.
 Hyperglycemia 3-5 hours after the meal  dual/combo
 Most important with evening meal as potential for prolonged
hyperglycemia vs daytime when awake to correct.
Smart CE et al. Conclusions
 Other studies suggest normal bolus for CHO and
square wave bolus of supplemental insulin for fat
and protein
 Reduced postprandial hyperglycemia however the
rate of hypoglycemia using this method is
unacceptably high (33-35%).
 So need further research for appropriate
algorithm.
But what about “real life”?
The day-to-day realities….
Received on Tuesday March 18th, 2014
“Hi Lorraine, Are you still coming to the Tues. April 29 meeting
as our guest speaker on Pump Tips and Tricks? I was in
Mississauga yesterday and saw ________ from the Trillium
Centre. Our group is going to the JDRF dinner at Boston
Pizza in May. I never eat there...too many carbs, fats and
calories!!!! _______ said to go and enjoy. It's a treat
dinner.”
Example 1: Boston Pizza Lasagna
Example 1: Boston Pizza Lasagna
Patient has an I:C Ratio of 1:10g and is having 1 order of the lasagna.




CHO: 62g
Fat: 49g
x 9 kcal/g = 441 kcal
Protein: 57g x 4 kcal/g = 228 kcal
TOTAL: 669 kcal  6 FPUs  equivalent to 60g additional ‘carbs’
Insulin Dose:
 Normal Bolus: 62/10  6.2 units
 Extended Bolus: 60 /10  6.0 units x 8h
Final thoughts…
Thank you! Questions?
Lorraine Anderson RD, CDE
Senior Clinical Manager, Animas Canada
landerso@its.jnj.com
416-303-0996
Animas® is a trademark of Animas Corporation.
All other trademarks are property of their respective owners.
© 2015 LifeScan Canada Ltd. AW105-076A 10/2015
22.2
16.7
16.7
11.1
11.1
5.6
BG (mmol /L)
22.2
Adapted from John Walsh, 2004
http://www.diabetesnet.com/diabetes_technology/super_bolus.php
5.6
BG (mmol /L)
Super Bolus
What are we aiming for?
“In all the work with diabetes technology I’ve done, I’ve
worn CGM for long periods of time. I don’t have diabetes,
but I’ll eat a dessert and go up to 200 mg/dl (11.1 mmol/L).
I’ll also drop down to 50 (2.8 mmol/L) or 60 mg/dl (3.3
mmol/L). People with diabetes are comparing themselves
to a false standard. The pancreas, for all of the advantages
it has, still allows big excursions. It’s crazy to think it’s ideal.”
-Dr. Steven Russell (Massachusetts General Hospital, Boston, MA) urging people with
diabetes not to be too hard on themselves at the 14th North American Conference on
Diabetes and Exercise in San Diego, CA, August 17-18.