Effect of DPP-IV Inhibitor on Glycemic Control and Autonomic Neuropathy in Adult Patients With Diabetes Mellitus

Study Overview
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Brief Summary
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Rocca et al. reported first that the secretion of incretins, particular GLP-1 in rat is regulated by the enteric nervous system, the afferent and efferent vagus nerves [1]. Further, Kazakos et al. [2] reported that autonomic nerve disturbance (AND) in patients with T2DM impaired the incretin effect owing to decreased GLP-1 secretion. However, Toft-Nielsen et al. [3] reported that the decreased GLP-1 responses in the patients with type 2 diabetes mellitus (T2DM) are unlikely to be related to the AND and, thus, did not support the results of Rocca et al. and Kazakos et al. Recently, Yabe at al. [4] also observed the same observations in Japanese patients with T2DM. Meanwhile, Jin et al. reported that administration of DPP-IV inhibitor recovered the disturbance of diabetic nerve dysfunction in rat [5]. However, it is unknown whether the administration of DPP-IV inhibitor effects on the AND in human, although many studies are performed to investigate the effect of the DPP-IV inhibitors on glycemic control. Accordingly, it is significant to reinvestigate an effect of DPP-IV inhibitor on glycemic control and autonomic neuropathy in diabetic patients.

Detailed Description
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Autonomic nerve disturbance (AND) is estimated to use coefficient of variance of electrocardiographic beat-to-beat intervals (C.V. R-R). Maximal change of the C,V. R-R with from usual breathing to deep breathing at the resting was used for the evaluation of AND. Less than 2.0 % of the maximal value is estimated to have a positive to AND. Glycemic control is estimated to measure change of HbA1c value once three months per year.

Official Title
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Effect of DPP-IV Inhibitor on Glycemic Control and Autonomic Neuropathy in Adult Patients With Diabetes Mellitus

Conditions
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Type 2 Diabetes Mellitus

Intervention / Treatment
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* Drug: Sitagliptin, 50 mg once per day per os


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: type 1 and 2 diabetes mellitus patients Patients who have AND determined by C.V. R-R. Outpatients regularly visiting hospital Patients 20 years old (gender is disregarded) Exclusion Criteria: Patients with a serious complication in the heart, liver or kidney Pregnant or possibly pregnant patients, or lactating patients Patients complicated with a malignant tumor at present. Patients participating in other clinical study. Other than the above, patients judged inappropriate as the subjects of this study by the investigator

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 95 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| DPP-IV inhibitor<br> | Drug: Sitagliptin, 50 mg once per day per os<br>* Before and one year after treatment with DPP-IV inhibitor in diabetic patients with AND.<br>* Other names: Nothing;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Glycemic control | As marker of HbA1c | For one year after treatment wih DPP-IV inhibitor | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| autonomic nerve disturbance | Before and after measurment with R-R CV in ECG at rest and respiratory deeping | Before and one year after treatment with DPP-IV inhibitor |