Effect of Glycemic Variability on Autonomic Tone in Hospitalized Patients With Type 2 Diabetes

Type 2 Diabetes Clinical Trial

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01409239
• Other study ID #: CCTS869
• Status: Completed
• Phase: Phase 4
• First received: August 2, 2011
• Last updated: November 11, 2013
• Start date: July 2011
• Est. completion date: December 2012

Study information

• Verified date: November 2013
• Source: Ohio State University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Food and Drug AdministrationUnited States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

Glycemic variability has been associated with mortality in hospitalized patients with hyperglycemia. However, it is unknown how modulation of glycemic variability would impact outcomes. One possibility is that glycemic variability could impact autonomic tone. In particular, heart rate variability (HRV) measurement is a sensitive marker for measuring autonomic tone, and aberrations in HRV have been associated with mortality. The current randomized pilot study will compare the effects of continuous intravenous (IV) insulin and subcutaneous basal bolus insulin on glycemic variability and autonomic tone in hospitalized non-critically ill patients with diabetes. Non-critically ill patients who are hyperglycemic or are requiring at least 20 units of insulin per day will be included. Patients with conditions that preclude accurate HRV readings (such as atrial fibrillation or paced rhythms) will be excluded. Patients randomized to intravenous insulin will receive the therapy for 24 hours according to our standard hospital guideline. Patients randomized to subcutaneous (SQ) insulin will receive basal bolus therapy using insulin analogues. All therapies will begin between 8 and 10 AM. Patients will undergo repeated heart rate variability recordings during the 24 hour period. Blood draws will be collected at baseline and at 24 hours for measurement of catecholamines, insulin, and c-peptide. Glycemic variability will be measured using a continuous subcutaneous glucose monitor and reported as coefficient of variation. The primary outcome measure is low frequency-to-high frequency power spectrum ratio of heart rate variability.

1. Glycemic variability is associated with unfavorable changes in autonomic tone, as assessed by low frequency (LF)/high frequency (HF) HRV ratio, independent of changes in overall glycemia.

2. Short-term increases in glycemic variability, followed by more prolonged glycemic stability are observed in generalized hospitalized patients treated with intravenous insulin compared to standardized basal bolus therapy. LF/HF HRV differs among subjects receiving intravenous compared to subcutaneous insulin.

3. Glycemic variability differs among subjects receiving intravenous compared to subcutaneous insulin

Recruitment information / eligibility

• Status: Completed
• Enrollment: 42
• Est. completion date: December 2012
• Est. primary completion date: June 2012
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Age 18 and above

• Admitted to a general medicine or medicine subspecialty service

• Insulin use (>20 units/day) or hyperglycemia. Hyperglycemia is defined as glucose greater than 180 mg/dL on at least 2 occasions separated by at least 4 hours apart.

Exclusion Criteria:

• Type 1 diabetes

• Hospital stay expected less than 48 hours

• Inability to consent

• Pregnancy

• Prisoners

• Previous participation

• Autonomic neuropathy

• Conditions that preclude accurate heart rate variability monitoring: atrial fibrillation, frequent ectopy, congestive heart failure, paced heart rhythms

• Conditions which require lower dose insulin algorithms: end stage renal or liver disease

Study Design

Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Diabetes Mellitus, Type 2
• Inpatient
• Type 2 Diabetes

Intervention

Drug:
• Intravenous insulin
24 hr IV insulin administered according to hospital guideline
• Subcutaneous Insulin
basal bolus insulin using carb counting technique and insulin analogues

Locations

Country	Name	City	State
United States	The Ohio State University	Columbus	Ohio

Sponsors (1)

Lead Sponsor	Collaborator
Kathleen Dungan

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Difference Between Heart Rate Variability Between Intravenous and Subcutaneous Group	difference in mean low frequency/high frequency heart rate variability (LF/HF HRV)at 6 hour. 2 patients were excluded who did not have usable LF/HF HRV data at 6 hours. These patients remained in the study as they did have other measures.	6 hour	No