Clinical trial NCT00836329: Improving Neurologic Outcomes in People With Diabetes Who Are Undergoing Heart Surgery
Official title: Improving Neurologic Outcomes in Diabetics Undergoing Cardiac Surgery
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE3
Conditions: Diabetes Mellitus
Cardiovascular Diseases
Keywords: Neurologic
Diabetes
Cardiac Surgery
Stroke
Lead sponsor: National Heart, Lung, and Blood Institute (NHLBI)
Sponsor class: NIH
First posted: 2009-02-04
Enrollment: 133
Sex: ALL
Minimum age (years): 35
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Preliminary studies have shown that people with diabetes who undergo heart surgery may have a higher risk of developing cognitive functioning problems, including memory problems, than people without diabetes who undergo heart surgery. Among people with diabetes, however, those who control their blood sugar levels in a more intensive way during and after heart surgery may have better neurological outcomes than those who use a standard method of controlling their blood sugar levels. This study will compare the effectiveness of using a traditional method of blood sugar control versus a more intensive method of blood sugar control during and after heart surgery for improving neurological outcomes in people with diabetes.

Detailed description: People with diabetes who undergo heart surgery have a greater risk of experiencing a stroke and developing cognitive functioning problems than people without diabetes who undergo heart surgery. There may be a connection between disturbances in glucose metabolism, endothelial dysfunction, and poor neurological outcomes after heart surgery. People with diabetes who receive more intensive blood glucose management during and after heart surgery may have better neurological outcomes than people who control their blood glucose levels in a standard way. The purpose of this study is to evaluate the effectiveness of using a traditional method of controlling blood glucose levels versus a tailored, more intensive method of glucose control on neurological outcomes in people with diabetes who are undergoing heart surgery. Researchers will also examine genetic factors that may be associated with insulin resistance and inflammation.

This study will enroll people undergoing heart surgery. On the day before surgery, participants will undergo a blood collection and neuropsychological testing. They will then be randomly assigned to either a traditional method of blood glucose control or an intensive, tailored method of blood glucose control. Participants following the traditional method of blood glucose control may receive insulin several times a day, based on the results of glucose monitoring. Participants following the intensive, tailored method of blood glucose control will undergo hourly measurements of their glucose levels and receive insulin adjustments as needed to maintain a glucose level of 100-140 mg/dL. During surgery, all participants will undergo an ultrasound of their neck to monitor blood vessel activity. Additional blood samples will be collected during surgery, 6 hours after surgery, 24 hours after surgery, and upon hospital discharge or 5 days after surgery.

One week after surgery or just before leaving the hospital, participants will undergo a magnetic resonance imaging (MRI) procedure and neuropsychological testing. Before leaving the hospital, participants will take part in a diabetes education session and nutrition counseling. Three to 6 weeks and 6 months after surgery, participants will undergo repeat neuropsychological testing. Once a month for 6 months, participants who received the intensive, tailored method of blood glucose control will attend study visits at which time study researchers will monitor their diabetes.

Eligibility criteria: Inclusion Criteria:

* History of diabetes, elevated fasting blood glucose, elevated hemoglobin A1c, or elevation of these variables during the current hospital admission
* Scheduled to undergo coronary artery bypass graft (CABG) surgery
* Scheduled to undergo aortic valve replacement (AVR), mitral valve replacement (MVR), or both
* Scheduled to undergo valve replacement with CABG

Exclusion Criteria:

* Undergoing emergent (i.e., urgent) procedures
* Alzheimer's disease or similar dementias
* Severe claustrophobia
* Kidney insufficiency, as defined by serum creatine levels greater than 2.0 mg/dL
* Cannot be expected to complete neuropsychological testing
* Recent extensive, life threatening acute myocardial infarction (AMI)

Primary outcomes:
measure: Proportion of participants with identifiable brain lesions detected by magnetic resonance imaging (MRI)
timeFrame: Measured 1 week after surgery
measure: Proportion of participants with new neuropsychological deficits (20% decline on two or more neuropsychological tests)
timeFrame: Measured 6 months after surgery
Secondary outcomes:
measure: Number of lesions, as measured by MRI
timeFrame: Measured 1 week after surgery
measure: Size of lesions, as measured by MRI
timeFrame: Measured 1 week after surgery
measure: Genetic analysis (i.e., predictive utility of haplotype assignment on primary outcomes)
timeFrame: Measured 6 months after surgery
measure: Neuropsychological deficits (i.e., predictive utility of neuropsychological performance on presence, number, and volume of lesions)
timeFrame: Measured 6 months after surgery
Other outcomes:
Locations:
city: Winston-Salem
country: United States
facility: Wake Forest Baptist Medical Center
state: North Carolina
Study officials:
affiliation: Wake Forest University Health Sciences
name: Edward H. Kincaid, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: Wake Forest University Health Sciences
name: Jorge Calles-Escandon, MD
role: STUDY_DIRECTOR
affiliation: Wake Forest University Health Sciences
name: Donald W. Bowden, PhD
role: STUDY_DIRECTOR
affiliation: Wake Forest University Health Sciences
name: David A. Stump, PhD
role: STUDY_DIRECTOR
References: