Vagal Blocking Improves Glycemic Control and Elevated Blood Pressure in Obese Subjects with Type 2 Diabetes Mellitus

<jats:p><jats:italic>Background</jats:italic>. An active device that downregulates abdominal vagal signalling has resulted in significant weight loss in feasibility studies.<jats:italic>Objective</jats:italic>. To prospectively evaluate the effect of intermittent vagal blocking (VBLOC) on weight loss, glycemic control, and blood pressure (BP) in obese subjects with DM2.<jats:italic>Methods</jats:italic>. Twenty-eight subjects were implanted with a VBLOC device (Maestro Rechargeable System) at 5 centers in an open-label study. Effects on weight loss, HbA<jats:sub>1c</jats:sub>, fasting blood glucose, and BP were evaluated at 1 week to 12 months.<jats:italic>Results</jats:italic>. 26 subjects (17 females/9 males,<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mn>51</mml:mn><mml:mo>±</mml:mo><mml:mn>2</mml:mn></mml:math>years, BMI<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mn>37</mml:mn><mml:mo>±</mml:mo><mml:mn>1</mml:mn></mml:math> kg/m<jats:sup>2</jats:sup>, mean ± SEM) completed 12 months followup. One serious adverse event (pain at implant site) was easily resolved. At 1 week and 12 months, mean excess weight loss percentages (% EWL) were<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mn>9</mml:mn><mml:mo>±</mml:mo><mml:mn>1</mml:mn></mml:math>% and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M4"><mml:mn>25</mml:mn><mml:mo>±</mml:mo><mml:mn>4</mml:mn></mml:math>% (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M5"><mml:mi>P</mml:mi><mml:mo><</mml:mo><mml:mn>0</mml:mn><mml:mo>.</mml:mo><mml:mn>0001</mml:mn></mml:math>), and HbA<jats:sub>1c</jats:sub>declined by<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M6"><mml:mn>0.3</mml:mn><mml:mo>±</mml:mo><mml:mn>0.1</mml:mn></mml:math>% and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M7"><mml:mn>1.0</mml:mn><mml:mo>±</mml:mo><mml:mn>0.2</mml:mn></mml:math>% (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M8"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0</mml:mn><mml:mo>.</mml:mo><mml:mn>02</mml:mn></mml:math>, baseline<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M9"><mml:mn>7.8</mml:mn><mml:mo>±</mml:mo><mml:mn>0.2</mml:mn></mml:math>%). In DM2 subjects with elevated BP (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M10"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn>15</mml:mn></mml:math>), mean arterial pressure reduced by<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M11"><mml:mn>7</mml:mn><mml:mo>±</mml:mo><mml:mn>3</mml:mn></mml:math> mmHg and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M12"><mml:mn>8</mml:mn><mml:mo>±</mml:mo><mml:mn>3</mml:mn></mml:math> mmHg (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M13"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.04</mml:mn></mml:math>, baseline<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M14"><mml:mn>100</mml:mn><mml:mo> ± </mml:mo><mml:mn>2</mml:mn></mml:math> mmHg) at 1 week and 12 months. All subjects MAP decreased by<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M15"><mml:mn>3</mml:mn><mml:mo> ± </mml:mo><mml:mn>2</mml:mn></mml:math> mmHg (baseline<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M16"><mml:mn>95</mml:mn><mml:mo> ± </mml:mo><mml:mn>2</mml:mn></mml:math> mmHg) at 12 months.<jats:italic>Conclusions</jats:italic>. VBLOC was safe in obese DM2 subjects and associated with meaningful weight loss, early and sustained improvements in HbA<jats:sub>1c</jats:sub>, and reductions in BP in hypertensive DM2 subjects. This trial is registered with ClinicalTrials.gov<jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://clinicaltrials.gov/ct2/show/NCT00555958">NCT00555958</jats:ext-link>.</jats:p>