The main objective of the proposed study is to investigate the effect of a VLCKD on body composition in patients undergoing bariatric surgery, and to compare this with a standard VLCD.
ID
Source
Brief title
Condition
- Other condition
- Appetite and general nutritional disorders
Synonym
Health condition
obesitas
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The reduction in FFM expressed in percentages in proportion to total body
weight loss, from baseline to 2 weeks after start of the diet, as confirmed by
multifrequency (MF) BIA and by Dual-energy X-ray Absorptiometry (DXA).
Secondary outcome
• Weight, measured by MF-BIA and DXA
• Body composition (FM, LBM and RMR)
• Total body weight loss
• Muscle strength, measured by handgrip peak strength
• Compliance, side effects and food intake, measured by self-reported
questionnaires and interviews
• Surgical outcomes including surgical time, hospital stay, complications and
re-admissions occurring within 30 days postoperative
• Biochemical tests including B-hydroxybutyrate, albumin, electrolytes (sodium,
potassium), liver function (AST = Aspartate Aminotransferase, ALT = Alanine
Transaminase, GGT = gamma glutamyl transpeptidase), kidney function
(creatinine, urea, eGFR), iron and hemoglobin, metabolic profile (total
cholesterol, LDL = low-density lipoprotein, HDL= HDL*high-density lipoprotein,
triglycerides), calcium, glucose.
• Physical activity, measured by International Physical Activity Questionnaire
(IPAQ)
• Patient satisfaction (5-point Likert scale: not at all satisfied, slightly
satisfied, neutral, very satisfied and extremely satisfied)
Background summary
Bariatric surgery is considered the most effective treatment for severe obesity
as it promotes significant long-term weight loss and improves or even resolves
obesity-related comorbidities. Preoperative weight loss is frequently advised
to overcome technical challenges during surgery. It may furthermore improve
short-term outcomes like surgical time, blood loss, hospital stay and
postoperative complications, as well as long-term outcomes like weight loss.
Preoperative weight loss can be realised by dietary regimens, like low-calorie
diets (LCD) (800-1500 kcal/day) and very low-calorie diets (VLCD) (<800
kcal/day). Downfalls of such diets are a loss of metabolically active fat free
mass (FFM), in continuing presence of an excessive fat mass, and some patients
may not tolerate a (V)LCD regime due to side-effects leading to poor compliance
and subsequently poor weight loss outcomes. Very low-calorie ketogenic diets
(VLCKD) have been proposed as a new diet for patients undergoing bariatric
surgery. VLCKD is characterized by a very low carbohydrate content (<50
g/daily), a low fat content (15-30 g fat/daily) and a high amount of proteins
(1-1.5 g protein/kg ideal body weight). The beneficial effect of VLCKDs
compared to (V)LCDs is the aimed preservation of FFM and therefore resting
metabolic rate, while still reducing fat mass. In addition, the compliance of
patients might be improved by VLCKDs, possibly thanks to the anorexigenic
effect and hunger reduction of ketone bodies. In our current care pathway
patients will start the VLCD two weeks prior to their scheduled RYGB. Only a
few small studies addressed the role of VLCKDs prior to bariatric surgery.
Therefore, we propose a randomised controlled trial to establish the efficacy
of a VLCKD compared to the standard VLCD.
Study objective
The main objective of the proposed study is to investigate the effect of a
VLCKD on body composition in patients undergoing bariatric surgery, and to
compare this with a standard VLCD.
Study design
An open trial with an hypothesised sample size of 46 patients.
Intervention
Control group:
The control group will receive the regular VLCD (standard care), two weeks
prior to their scheduled RYGB
Intervention group:
The intervention group will receive the VLCKD, two weeks prior to their
scheduled RYGB
Study burden and risks
Burden:
- A burden that patients may experience from this research is that their
appointments in the hospital can take longer. Carrying out body composition
studies takes time, and filling in the questionnaires also takes time. They
will be in the hospital approximately 45 minutes longer because of this.
Patients will receive up to 3 extra check-ups for which they will have to fill
in questionnaires several times. Patients do not have to visit the hospital
extra for this, as these coincide with the standard hospital visits already
planned or these questionnaires can be completed from home.
- Additional blood test are needed. In our current care path, patients only
need to undergo one blood test. In this study there will be an additional blood
test necessary.
Risks:
- The diet to be studied may have side effects. Side effects that patients may
experience from the ZLCKD diet include bad breath, headache, dry mouth,
dizziness, low blood sugars (hypoglycemia) and decreased energy and
hyperuricemia. These side effects can also occur with normal diets. Another
side effect that can occur, which is very rare, but should be mentioned, is
that a patient has a slightly increased risk of kidney stones and possible gout
attacks.
Due to the ZLCKD diet, the patient ensures that the blood sugar remains at a
more stable level and will not experience highs and lows, because patients eat
almost no carbohydrates, but the metabolism depends on fats and proteins. This
could mean that patients can endure a slightly higher chance of a hypoglycemia.
Dominee Theodor Fliednerstraat 1
Eindhoven 5631 BM
NL
Dominee Theodor Fliednerstraat 1
Eindhoven 5631 BM
NL
Listed location countries
Age
Inclusion criteria
In order to be eligible to participate in this study, a subject must meet all
of the following criteria: Patients with the age of 18-65 years are included if
they are scheduled for a primary laparoscopic Roux-en-Y gastric bypass (RYGB)
because of severe obesity. The latter is classified as a body mass index (BMI)
of >=35 kg/m2 with obesity-related comorbidities, or a BMI of >=40 kg/m2 with or
without comorbidities
Exclusion criteria
• Weighing over 150kg because this amount is a limitation by the DXA device
• Diabetes mellitus type 1
• Allergic to milk proteins
• A recent history of a heart attack (< 12 months), heart failure or cardiac
arrhythmias
• Kidney and/or liver failure (creatinine levels >1.3 mg/dl or liver enzyme
levels (AST, ALT, GGT) less than three times over the upper normal threshold
• Current infectious, sepsis or malignant disease
• Rare condition like galactosemia, phenylketonuria or porphyria
• Persistent diarrhoea
• Hypokalaemia, chronic therapies with diuretics as furosemide and
hydrochlorothiazide
• Pregnancy or plans to get pregnant in the coming months
• Patients who did not meet criteria to be eligible for bariatric surgery (BMI
<35, psychological or unstable psychiatric disorders, inadequate dietary
regimen or inadequate exercise pattern which can*t be resolved in the upcoming
6 months)
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL81550.015.22 |