Maenne Okunola
Pharm D Candidate:
University of Georgia
June 3, 2012
Preceptor Dr. Ali Rahimi
Level of Evidence
Intervention to Decrease
Glyburide Use in Elderly Patients
With Renal Insufficiency
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Authors: Aspinall, Zhao, Good, Stone, Boresi,
Cox, Bartholomew, Jansen, Guterman, Patino,
Rivera-Miranda, Burlingame, Frazer, Sellers,
Steele, Witt, Cunningham
The American Journal of Geriatric
Pharmacotherapy 2011; 9:58-68
This study examines the changes in
prescribing of glyburide in elderly patients
with decreased renal function and the
adverse effects of discontinuing therapy
Background Information
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Sulfonylureas have an increased rate of hypoglycemia
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Predisposing factors include renal insufficiency, advanced
age, dose, concomitant medications, and beginning new
therapy
Glyburide is not recommended in patients with CrCl
less than 50ml/min
Reason for study: Veterans Affairs Center for
Medication Safety received a report of severe
hypoglycemia associated with glyburide use and the
majority of the patients were elderly and renally
impaired
Design
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Uncontrolled observational study
4368 targeted outpatient Veterans and 1886 nontargeted Veterans in the comparison group
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Targeted Veteran Cohort: SrCr ≥ 2 and age ≥ 65 with
prescription of glyburide during April 1- June 30
Non-targeted Veteran Cohort: SrCr ≥ 2 and age ≥ 65 with
prescription of glyburide during July 1 to September 3
Duration of study: The date they met requirements
of the study to March 31, 2008. (longest duration
April 1,2007-March 3,2008)
Patient Demographics
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Targeted group: 77
years, male,
Caucasian, 2.5 SrCr,
3.8 Charlson
comorbidity index
score
Non-targeted group:
77 years, male,
Caucasian, 2.3 SrCr,
3.5 Charlson
comorbidity score
Design
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Information given to Pharmacy Executives in 21 VA
geographic areas on September 4,2007:
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Compiled collected data from April 1, 2007- June 30 of
patients age over 65 and SCr of >2 (targeted Veterans)
Data on the risk of risk of hypoglycemia of glyburide
compared to other sulfonylureas
Data on the risk of hypoglycemia of glyburide in patients
with renal failure
Dosing and monitoring suggestions for patients converted to
glipizide
Instructions to pharmacy executives to contact
providers and inform them of the risk with glyburide
and encourage a change in therapy
Data Evaluated
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Monthly glyburide incidence rate ratios of
discontinuation in targeted versus
nontargeted groups
Variability of glyburide discontinuation rates
by geographic area
Medication to replace glyburide
Patient specific factors associated with
stopping glyburide
Comparisons of hypoglycemia in patients with
and without more severe renal insufficiency
Clinical Endpoints
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Primary endpoint
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Changes in glyburide prescribing comparing
targeted groups to non-targeted groups
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A new prescription for a sulfonylurea or no new
prescriptions for glyburide 135 days after the prescription
date
Secondary endpoint:
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Change in HbA1c after stopping glyburide
Comparison of of hypoglycemia before and after
discontinuing glyburide
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Hospitalization or ER visit
Results
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IRR
95%
CI
Sep.
2.1
1.7-2.5
Oct.
1.3
1.1-1.6
Nov.
1.4
1.1-1.7
Primary Endpoints
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-
Incidence rate ratios (IRR)
for discontinuing glyburide
was statistically
significantly elevated in the
months of September,
October, and November for
the targeted group
compared with the nontargeted group
Remainder of the study the
discontinuation rates were
not significant
Results
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Overall glyburide discontinued in 71.5% of
targeted cohort and 56% of the non-targeted
cohort
Glyburide most commonly switched to
glipizide
African-American race, SCr, Charlson
comorbity score, new glyburide use and the
VA regions were all associated with physician
discontinuation
Results
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Secondary endpoints
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For patients in the targeted group who
discontinued glyburide
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Baseline HbA1c: 7.17%
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After discontinuation HbA1c: 7.22%
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Baseline - most recent value within 3 months of index date
Value 3-9 months after discontinuing glyburide
Baseline hypoglycemia rates/1000 person-days: 0.093
(p-value 0.36)
After discontinuation Hpoglycemia: 0.070 (p-value 0.10)
Results- Renal Comparison
SCr ≥
3mg/dL
SrCr 2-3
3mg/dL
Pre intervention
hypoglycemia
rate
0.169/1000
person days
0.081/1000
person days
Postintervention
hypoglycemia
rate
0.039/1000
person days
0.075/1000
person days
Conclusion
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This intervention to target elderly
patients with proposed renal
insufficiency decreased glyburide use
over 3 months without compromising
glucose control and without major
detrimental effects
Limitations
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Uncontrolled observational study
SrCr was the marker for renal function instead of
creatinine clearance
Information sent to the targeted group could have
had profound effects on the prescribing for the nontargeted group because information could have
spread
Only looked at the first time glyburide was
discontinued although it might have been re-started
Hypoglycemia codes may be more strict within the VA
versus outside the VA
Importance to Health Care
Professionals
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Continued research to decrease
glyburide use in elderly patients with
renal insufficiency
Risk of hypoglycemia more prevalent in
the elderly taking sulfonylurea