DRIVeS: Dietary Restriction in Vascular Surgery

Sponsor
Brigham and Women's Hospital (Other)
Overall Status
Completed
CT.gov ID
NCT04013412
Collaborator
(none)
19
1
2
15
1.3

Study Details

Study Description

Brief Summary

A randomized, controlled trial to evaluate patient compliance and biologic mechanisms of a short-term pre-operative Protein-Calorie Restriction (PCR) diet in comparison to a normal ad libitum diet for 4 days before elective vascular surgery involving a major operation. This study is a step in the long-term primary scientific objective to test the hypothesis that brief up regulation of endogenous H2S via pre-operative PCR in elective major surgery improves clinical outcomes in humans. After a successful pilot study of the PCR diet conducted inpatient before carotid endarterectomy, the investigators now aim to expand the study to at home diet among a variety of vascular surgery procedures.

Condition or Disease Intervention/Treatment Phase
  • Dietary Supplement: Protein-Calorie Restriction
N/A

Detailed Description

Hydrogen sulfide (H2S) has emerged as a critical gaseous signaling molecule with a role in multiple processes including ischemia-reperfusion (IR) injury, angiogenesis, intimal hyperplasia, and anti-inflammatory mechanisms. It even appears to hold anti-atherosclerotic properties. However, the gas is toxic with a half-life of minutes, and it can be rapidly oxidized. Furthermore, no clinically useful pharmacologic H2S donors have been developed to date. In a 2015 Cell paper, the study investigators link substantial upregulation of endogenous H2S to short-term manipulation of mammalian dietary intake: simple dietary restriction. The current project serves as the second phase in the accelerated translation of this important discovery toward clinical utility that may substantively impact the vascular patient at several levels: protection from IR injury, intimal hyperplasia, peri-procedural events such as stroke, cardiac dysfunction and myocardial infarction (MI), and promotion of angiogenesis.

Chronic protein and calorie dietary restriction (PCR; reduced food intake without malnutrition) is known for extending longevity in multiple species. PCR is also an established approach to positively impact metabolic fitness and resistance to multiple forms of acute stress. Despite these wide-ranging benefits, potential clinical applications have never been considered feasible in humans due to the practical difficulties associated with voluntary food restriction combined with the assumption that PCR benefits take a long time to accrue. Recent preclinical studies by the applicants reveal a rapid onset of PCR benefits against surgically induced traumatic inflammation, IR injury, and the fibroproliferative vascular response to injury in rodents. Mechanistically, rapid changes in adipose phenotype and associated adipokine profiles appear to underlie these benefits; but the key mediator appears to be endogenous H2S. This field thus stands poised to move to clinical utility, and vascular surgery offers an optimal risk/benefit ratio for translation of the PCR/H2S hypothesis.

For the current project the investigators will complete a randomized, controlled trial to evaluate patient compliance and biologic mechanisms of a short-term pre-operative PCR diet in comparison to a normal ad libitum diet for 4 days before elective major vascular surgery. Both Endpoints relate to the long-term primary scientific objective to test the hypothesis that brief upregulation of endogenous H2S via pre-operative PCR in elective major surgery improves clinical outcomes in humans. After a successful pilot study of the PCR diet conducted inpatient before carotid endarterectomy titled Short-Term Endogenous Hydrogen Sulfide Upregulation (NCT03303534), the investigators now aim to expand the study to at home diet among a variety of vascular surgery procedures.

Eighty subjects undergoing carotid artery endarterectomy, aortic aneurysm repair (open, and endovascular if groin cut down planned), open lower extremity arterial procedures (bypasses, aneurysm repair, arterial and bypass graft reconstructions), major amputation of the lower extremity (below knee and above knee amputations), or open hemodialysis access procedures for either symptomatic or asymptomatic disease will be recruited and enrolled at Brigham and Women's Hospital. Using a randomized (3:2), parallel design, patients will receive either the PCR diet (n=48; ScandiShake [any of 4 flavors] mixed with almond milk, calculated individually for a total daily volume to achieve 30% caloric restriction and 70% protein restriction, based on body weight and activity level), or continued routine ad libitum diet (n=32). Daily physical activity will be assessed by questionnaire to determine the activity factor for accurate calorie restriction calculations. Water intake is ad libitum for both cohorts, and both diets can be consumed throughout the day and night (except on the day of surgery). Patients will consume their assigned diets for the four days leading up to surgery until midnight the day of surgery when both cohorts will be fasted for the procedure (per standard clinical guidelines).

Study Design

Study Type:
Interventional
Actual Enrollment :
19 participants
Allocation:
Randomized
Intervention Model:
Parallel Assignment
Intervention Model Description:
3:2 randomization to short-term protein calorie restriction diet versus regular meals prior to elective major vascular surgery3:2 randomization to short-term protein calorie restriction diet versus regular meals prior to elective major vascular surgery
Masking:
None (Open Label)
Primary Purpose:
Prevention
Official Title:
Dietary Restriction in Vascular Surgery
Actual Study Start Date :
Dec 31, 2018
Actual Primary Completion Date :
Mar 31, 2020
Actual Study Completion Date :
Mar 31, 2020

Arms and Interventions

Arm Intervention/Treatment
Experimental: Protein-Calorie Restriction

Four day dietary intervention immediately before surgery of ScandiShake [any of 4 flavors] mixed with almond milk, calculated individually for a total daily volume to achieve 30% caloric restriction and 70% protein restriction, based on body weight and activity level.

Dietary Supplement: Protein-Calorie Restriction
Four day dietary intervention immediately before surgery of ScandiShake [any of 4 flavors] mixed with almond milk, calculated individually for a total daily volume to achieve 30% caloric restriction and 70% protein restriction, based on body weight and activity level.

No Intervention: Control

Ad libitum diet for four days immediately before surgery

Outcome Measures

Primary Outcome Measures

  1. Outpatient compliance with protein calorie restriction [1 Month]

    Patient compliance with the PCR diet will be assessed by food record analysis.

  2. Comparison of H2S and related biological markers of stress [1 Month]

    Biologic markers include: adipose phenotyping (quantification of adipokines, adipose derived hormones), leukocyte phenotyping and quantification via flow cytometry, and serum assays of IL-1beta, IL-6, IL-8, HGF, leptin, MCP-1, PAI-1, resistin, NGF, TNF, adiponectin, hydrogen sulfide (including production capacity) assays, insulin, lipid panels, FGF 21, pre-albumin, epinephrine, norepinephrine, dopamine, CBC with differential, basic metabolic panel including calcium. H2S and biologic markers will be compared at baseline, immediately before surgery, and the day after surgery.

Eligibility Criteria

Criteria

Ages Eligible for Study:
18 Years and Older
Sexes Eligible for Study:
All
Accepts Healthy Volunteers:
No

Inclusion Criteria

• Patients greater than 18 years old who present for one of the following elective procedures at Brigham and Women's Hospital

  • Carotid artery endarterectomy

  • Aortic/iliac aneurysm repair (open, and endovascular if groin cut down planned)

  • Open lower extremity arterial procedures (bypasses, aneurysm repair, arterial and bypass graft reconstructions)

  • Major amputation of the lower extremity (below knee and above knee amputations).

  • Open hemodialysis access procedures

Exclusion Criteria

  • Patient intolerance or allergy to any of the ingredients in the PCR diet

  • Active infection

  • Pregnancy

  • Malnutrition, based on abnormally low serum albumin (lower than 3 g/dL)

  • Uncontrolled diabetes (HgbA1c greater than 12%)

  • Substance dependency that could interfere with protocol adherence and assent as determined by the PI

  • Active non-cutaneous cancer under treatment with chemotherapeutics or radiation

  • Emergency surgery

  • Active participation in any another interventional or randomized study

  • Participation in the current study within the past 30 days

Contacts and Locations

Locations

Site City State Country Postal Code
1 Brigham and Women's Hospital Boston Massachusetts United States 02115

Sponsors and Collaborators

  • Brigham and Women's Hospital

Investigators

  • Principal Investigator: Charles K Ozaki, MD, Brigham and Women's Hospital

Study Documents (Full-Text)

More Information

Publications

Responsible Party:
C. Keith Ozaki, M.D., F.A.C.S., John A. Mannick Professor of Surgery, Brigham and Women's Hospital
ClinicalTrials.gov Identifier:
NCT04013412
Other Study ID Numbers:
  • 2018P002133
First Posted:
Jul 9, 2019
Last Update Posted:
Sep 25, 2020
Last Verified:
Sep 1, 2020
Individual Participant Data (IPD) Sharing Statement:
No
Plan to Share IPD:
No
Studies a U.S. FDA-regulated Drug Product:
No
Studies a U.S. FDA-regulated Device Product:
No
Additional relevant MeSH terms:

Study Results

No Results Posted as of Sep 25, 2020