Diabetes Update: Living
Life after Lente
Stacey B. Hoffman, DACVIM
November 4, 2010
ProZinc Insulin (Boehringer)
 Protamine zinc insulin (PZI), human
recombinant product (4 aa difference)
 Replaces PZI Vet (Idexx), beef/pork
source insulin no longer manufactured
 Pilot studies suggest that both products
have similar potency, onset & duration of
action (PZI onset 1-4 hrs, duration 9-10
hrs)
Treatment of diabetic cats with
ProZinc, Norsworthy et al (Vet Therapeutics 10(12): Spring-Summer 2009
 50 diabetic cats, on PZI Vet > 90 days
 No change in diet or insulin dose,
converted to ProZinc at PZI Vet dose
 47 cats completed study, 38/47 did not
have any change in dose over 30 days
 Evaluated weight, fructosamine, clinical
signs @ 15 days (dose change < 2 units)
Long-acting insulin analogues
 Synthetic human products: detemir
(Levemir®) , glargine (Lantus®)
 “Peakless” in humans, continuous basal
insulin concentrations
 Glargine: very efficacious in cats,
unpredictable serum levels in dogs
Use of insulin detemir in dogs, Ford
et al (ACVIM Forum 2010)
 Prospective study 13 dogs
 Most (10/13) previously txd with NPH or
Vetsulin- poor response
 All dogs monitored with home blood
glucose monitoring
Use of detemir in dogs
 Initial dose: 0.1-0.2 U/kg BID (thought to
be about 4x more potent than prev.
insulins)
 Improved glycemic control all dogs
 Biochemical hypoglycemia more
common small dogs
 Not a first choice (particularly small dogs)
but could be option for refractory cases
Use of insulin glargine in DKA cats
 I.V. glargine lowers blood glucose like
regular insulin (humans)
 Adding SQ glargine to CRI regular insulin
lead to faster resolution DKA in kids (1
study)
 Two recent studies using glargine DKA
cats
Glargine administered IM effective
for tx feline DKA (Marshall, et al ACVIM 2010)
 Retrospective 15 cats, substituted IM
glargine for IM regular insulin
 1-2 U glargine IM +/- 1-3 U glargine SQ
 Continue SQ glargine q. 12 hours,
additional IM doses 2-22 hours later until
glucose 180-250 mg/dl
IM glargine DKA cats
 All cats survived to discharge (historical
survival rate ~ 80%) after 2-5 days hosp.
 Half of cats that received both IM and SQ
glargine (6/12) able to be managed SQ
insulin only after 18 hours
Intermittent insulin protocol
improves acidosis faster than CRI
(Buob et al, ACVIM 2010)
 16 ketoacidotic cats: 8 CRI regular insulin
sliding scale, 8 SQ glargine + intermittent
regular insulin IM
 Intermittent protocol: 0.25 U/kg glargine
SQ BID plus 1 U regular insulin IM up to
q. 8 hours
 Primary endpoint: time to resolution
acidosis
Intermittent insulin protocol vs. CRI
DKA cats
 No differences between groups at
baseline
 11/16 cats survived to discharge (6/8 CRI
cats, 5/8 intermittent cats)
 Time to resolution of metabolic acidosis:
16 hours (intermittent) vs. 38 hours (CRI)
Modified feline DKA protocol using
insulin glargine
 All cats receive SQ glargine 0.25 U/kg
BID (small cat= 1U, larger cat= 2U)
 Supplemental 1-2 unit IM glargine
injections q. 8 hours (monitor BG)
 Less technical monitoring, can use 1
bottle insulin
 Resolution of ketoacidosis not resolution
of illness!
Continuous glucose monitoring
in ketoacidotic diabetics
 Glucose of interstitial fluid mimics blood
glucose concentrations several species
 DKA patients often have rapid changes in
blood glucose (compromised
homeostasis, therapeutics)
 Continuous interstitial glucose monitoring
systems (CGMS) allow semicontinuous
estimates of BG concentration
Continuous blood glucose
monitoring
 Interstitial fluid equilibrates 10-12 minutes
following glucose bolus
 Correlates well with blood glucose (dog,
cat)
 Record data q. 5 minutes (288 times/day)
Accuracy of CGMS in DKA patients
Reineke et al (JVECC 20(3): 2010)
 23 patients, prospective study (13 dogs,
11 cats)
 Data collected min. 3 days (8 days max)
 Monitor calibrated q.8-12 hours with
portable BG monitor
 Interpatient variability, but no difference
in accuracy between dogs and cats
Accuracy of CGMS in DKA
 Good correlation between CGMS
measurements and lab BG
measurements (r=0.86)
 Based on error grid measurements, 9799% of readings clinically acceptable (no
change in treatment recommendation)
 Not real-time monitoring
Real-time Continuous Glucose
Monitoring in Cats (JVIM 2010: 24: 120-126)
 Guardian REAL-Time system, provides
instantaneous interstitial glucose conc.
 Initial report: used in one diabetic cat,
identified hypoglycemia due to insulin
overdose
 Studied 32 diabetics, 2 insulinoma
suspects, 5 healthy cats
Continuous glucose monitoring cats
 Clinically accurate in euglycemic and
hyperglycemic cats (less in
hypoglycemia)
 Delay after IV glucose administration to
increased interstitial glucose= 11 min.
 Advantages: real time info, patient
doesn’t have to wear monitor (just
sensor/transmitter)
Uses of Guardian REAL-Time CGMS
 Inpatient monitoring: ketoacidosis,
hypoglycemia
 Outpatient monitoring: continuous blood
glucose curves
 Advantages: reduces stress, collects
information up to 3 days
 Disadvantages: glucose range 40-400
mg/dL, needs calibration 2x/day
Any questions?