Bariatric Surgery and Reactive Hypoglycemia
Bariatric Surgery and Reactive Hypoglycemia
Bariatric surgery has long been recognized as an effective treatment for grade 3 or grade 2
 obesity associated with complications. Among the bariatric surgical procedures, roux-en-y
 gastric bypass (RYGB) was shown to account for 41% of all bariatric operations at least in
 the United Sates. Sleeve gastrectomy (SG), that was conceived as the first step before
 performing a RYGB or a biliopancreatic diversion with duodenal switch in patients who were
 super-obese, has recently emerged as a new restrictive bariatric procedure.

 Reactive hypoglycemia is a late complication affecting up to 72% of RYGB patients although it
 seems to occur also after SG, in about 3% of the cases. However, until now no prospective
 studies have investigated the incidence of hypoglycemia after RYGB nor randomized studies
 have been undertaken to compare the effect of SG to that of RYGB in terms of incidence of
 hypoglycemic episodes.

 The primary aim of the present study is to conduct a 1-year randomized trial to compare the
 incidence of hypoglycemia after RYGB or SG.
INTRODUCTION Geltrude Mingrone,Simona Panunzi, Andrea De Gaetano, Caterina Guidone, Celestino
 Pio Lombardi, Marco Raffaelli,Rocco Bellantone Departments of Internal Medicine, Surgery and
 Biomathematics of the Catholic University of Rome, Italy

 The overall prevalence of grade 2 and 3 adult obesity (BMI> 35 kg/m2) derived from the
 2009-2010 National Health and Nutrition Examination Survey (NHANES) exceeded 15% and grade 3
 obesity (BMI > 40 kg/m2) accounted for 6.3% (1). The dietary approach is modestly
 satisfactory in the short term and weight regain is practically the rule in the long run as a
 consequence of the scarce compliance to the diet shown by the obese subjects. In fact, in a
 recent study (2) where different types of diets were assigned to a population of overweight
 and obese subjects (BMI from 25 to 40 kg/m2), an average of 6 kg, corresponding to 7% of the
 initial body weight, was lost in the first 6 months, but the weight was regained after 1 year
 and at 2 years, only 31-37% of the participants had lost 5% of their initial weight.

 Bariatric surgery has long been recognized as an effective treatment for grade 3 or grade 2
 obesity associated with complications (3) and, accordingly, the number of bariatric
 operations in the United States is growing over time from ca. 10,000 in the early 1990s to
 103,000 in 2003 (4).

 Bariatric surgery allows to type 2 diabetes remission (5,6) while improving several other
 serious comorbidities (7). Among the bariatric surgical procedures, roux-en-y gastric bypass
 (RYGB) was shown to account for 41% of all bariatric operations at least in the United Sates
 (8). Sleeve gastrectomy (SG), that was conceived as the first step before performing a RYGB
 or a biliopancreatic diversion with duodenal switch in patients who were super-obese (9), has
 recently emerged as a new restrictive bariatric procedure (10). It was noticed that SG
 determines a weight loss similar to that achieved after RYGB (11) and larger than that
 following laparoscopic adjustable gastric banding (12,13).

 Reactive hypoglycemia is a late complication of RYGB although it seems to occur also after
 SG.

 After RYGB insulin secretion is enhanced early after an oral glucose tolerance test (OGTT)
 (14) or a meal (15,16) and might explain the later reactive hypoglycemia. An increasing
 number of reports highlight the occurrence of severe hypoglycemia after RYGB including
 neuroglycopenia that is attributed to nesidioblastosis (17-20). Roslin et al (21) found that
 72%, i.e. 26 out of 36 patients operated of RYGB 6 months earlier, had reactive hypoglycemia
 at 2 hours after an OGTT (100 g of glucose), which was defined as "an absolute serum glucose
 level ≤60 mg/dL, or a drop of 100 mg/dL in serum glucose level in 1 h".

 As compared with RYGB, SG seems to have a much lower occurrence of reactive hypoglycemia, ca.
 3%, i.e. 1 out of 31 patients studied at 6 weeks after the operation (22).

 Fortunately, the frequency of severe hypoglycemia or related symptoms requiring
 hospitalization after RYGB is pretty low, the adjusted hazard ratios were in fact 2.7 for
 hypoglycemia, 2.8 for confusion, 4.9 for syncope, 3.0 for epilepsy and 7.3 for seizures (23)
 in a Swedish cohort study based on national registries with 5,040 operated persons (23).

 However, until now no prospective studies have investigated the incidence of hypoglycemia
 after RYGB nor randomized studies have been undertaken to compare the effect of SG to that of
 RYGB in terms of incidence of hypoglycemic episodes.

 The primary aim of the present study is to conduct a 1-year randomized trial to compare the
 incidence of hypoglycemia after RYGB or SG.

 STUDY OBJECTIVE

 Primary objective The primary objective of the study is to verify whether SG decrease the
 percentage of patients presenting with reactive hypoglycemia with respect to RYGB within 1
 years after the bariatric operation.

 Secondary objectives

 -  To quantify the relative contribution of changes in insulin sensitivity and insulin
 secretion measured after an OGTT to the glycemic effect of bariatric surgery and to
 determine if differences exist between the two surgical treatments.

 -  To determine whether treatment is associated with body weight, BMI and abdominal
 circumference loss and with body composition, as assessed by DEXA, as well as with lipid
 profile and cardiovascular system abnormalities.

 -  To assess the occurrence of severe hypoglycemia or related symptoms (shakiness,
 sweating, dizziness or light-headedness, confusion, difficulty speaking, weakness,
 confusion, syncope, epilepsy, seizures) within 5 years after the operation and determine
 whether SG decrease its incidence.

 EXPERIMENTAL DESIGN Study End-points

 Primary End-point The Primary Endpoint of the study is the incidence reactive hypoglycemia at
 1 year after the bariatric surgery.

 Secondary End-points

 -  Changes at 1 year of insulin sensitivity and insulin secretion measured after an OGTT.

 -  Changes at 1 year of body weight, BMI, abdominal circumference, body composition, lipid
 profile and cardiovascular system abnormalities.

 -  the incidence of severe hypoglycemia or related symptoms (shakiness, sweating, dizziness
 or light-headedness, confusion, difficulty speaking, weakness, confusion, syncope,
 epilepsy, seizures) within 5 years after the operation.

 Experimental plan This is a monocentric prospective controlled randomized clinical trial
 designed to investigate if the SG reduces the incidence of reactive hypoglycemia with respect
 to RYGB within 1 years after the bariatric operation.

 At the moment of the Screening visit subjects will be randomized to be undergone either the
 SG or the RYGB surgical procedure.

 Study Design diagram

 The diagram of the study plan is as follows:

 Screening Visit (-18 weeks) Baseline Visit (-4 weeks) Follow-up Visit (+1 month) Follow-up
 Visit (+3 months) Follow-up Visit (+6 months) Follow-up Visit (+9 months) Follow-up Visit
 (+12 months) Written informed consent Demographic Data Medical and surgical history Physical
 examination† Height weight, BMI waist and hip circumference DEXA blood pressure and heart
 rate ECG laboratory assessments OGTT adverse events recording concomitant medication An
 overview of all planned blood samples, including volumes and purpose is provided in Table 2.

 Study duration

 Subjects will be studied from the time of Screening Visit to 1 year after the surgical
 procedure and will undergo four distinct phases:

 -  Screening visit (week -18)

 -  Baseline visit (week -4)

 -  A follow-up period after the surgical treatment (1 year of duration, month 1, 3, 6, 9,
 12)

 -  A further follow-up period after study conclusion (4 years of duration)

 Screening Visit At week -18, eligible patients are identified and the Written informed
 consent is obtained. Demographic data, anthropometric measures, physical examination and
 information about medical history, concomitant medication and variables related to inclusion
 criteria are collected.

 Basal Visit At week -4 patients at the screening visit will be asked to return for the
 baseline visit and they will be asked to give their informed consent to randomization. Study
 compliance will be assessed during the screening and baseline periods using attendance at
 appointments and completion of questionnaires. Baseline anthropometric measures, body
 composition, blood pressure, and biochemical data (levels of fasting plasma glucose, glycated
 hemoglobin [HbA1c], C-peptide, and serum insulin, lipid profile and oral glucose tolerance
 test) are measured.

 Follow-up Period One month after the bariatric surgery and each 3 months until 1 year after
 the surgical treatment (month 1, 3, 6, 9, 12) all the collected variables at baseline will be
 recorded and an OGTT will be performed. Adverse events will be recorded at each follow-up
 visit.

 Study conclusion and a further follow-up period At the conclusion of the a study a conclusion
 form will be filled in and patients will be followed up to 5 years after the surgical
 treatment.

 STUDY POPULATION

 Sample size The sample size depends on the magnitude of the difference in reactive
 hypoglycemia incidence as derived from previous studies (21) and (22). The study is designed
 to detect a more conservative absolute difference in the occurrence of hypoglycemia of 50%,
 expecting an incidence of 70% in the RYGB group versus an incidence of 20% in the SG group. A
 sample size of 19 patients per group would be required for this clinical trial to detect an
 improvement data significance level of 0.05 and a power of 0.90. Considering an attrition
 rate of 25% over the course of the study a total of 50 subjects (25 for each group) will be
 enrolled.

 An amendment to enlarge the number of patients to 120, 60 in each arm, was approved by the
 Ethical Committee on November 2012. For a more conservative estimate in fact, we have reduced
 the percent difference between the two groups from 50% to 30% considering the incidence of
 reactive hypoglycemia to be 50% in RYGB and to 20% in SG instead of 70% and 20% respectively.
 In this way, the number of patients to be allocated in each arm is 50 with a power of 90%.
 Considering an attrition rate of 20% the number of patients in each group will be 60 and,
 thus, overall 120. Secondary endpoints for CGM and insulin sensitivity and secretion are
 evaluated in a subset of 50 patients, 25 in each Group, but can be also extended to entire
 sample.

 Selection study population Patients will be recruited from the Outpatient Clinics and Day
 Hospital of Obesity of the Catholic University of Rome, Italy. The study will be subject to
 revision and approval by the Ethical Committee of the above institution in accordance with
 the guidelines of the National Health Ministry and the Helsinki Declaration, as revised in
 2000. All participants will provide written informed consent to participate in the study.
 Additional written informed consent will be obtained prior to the surgical procedure.

 Inclusion Criteria Patients are eligible if aged between 25 and 65 years, have a body mass
 index of 35 (in presence of complications as sleep apnea, severe coxarthritis or
 gonarthritis, severe hypertension) to 50 kg/m2, and are able to understand and comply with
 the study process.

 Exclusion Criteria

 -  History of type 1 diabetes or secondary diabetes;

 -  Previous bariatric surgery;

 -  History of medical problems such as mental impairment;

 -  Major cardiovascular disease;

 -  Major gastrointestinal disease;

 -  Major respiratory disease;

 -  Hormonal disorders;

 -  Infection;

 -  History of drug addiction and/or alcohol abuse;

 -  Internal malignancy;

 -  Pregnancy;

 -  Impaired glucose tolerance;

 -  Suspected or confirmed poor compliance;

 -  Informed consents; Participants will be excluded if they did not attend at least 2
 initial information visits.

 TREATMENT

 Surgical Program Within 1 month of randomization the patients will undergo RYGB or SG.

 Roux-en-Y Gastric Bypass This laparoscopic operation includes the division of the stomach in
 two parts. A proximal, smaller pouch (20-25 cc volume), is connected to the rest of the
 gastrointestinal tract through a gastro-jejunal anastomosis, whereas the distal gastric pouch
 is left behind but excluded from the transit of food.

 An entero-entero anastomosis, with a Roux-en-Y type of reconstruction, allows the bile and
 pancreatic juices to mix with the nutrients at about 100-150 cm from the gastro-jejunal
 connection.

 Sleeve gastrectomy Laparoscopic SG involves a longitudinal resection of the stomach on the
 greater curvature from the antrum starting opposite of the nerve of Latarjet up to the angle
 of His The final gastric volume is about 100 mL.

 Randomization Process Automatic dynamic allocation of the treatment to the patients will be
 performed via a Web-based software. The randomization procedure via Internet is an automatic
 and flexible mechanism that on one hand guarantees random allocation and on the other hand
 reduces imbalance with respect to the two treatment groups over the two considered
 stratification factors: gender and age (18-40 and 40-60). The mechanism may be accessed from
 any web-connected computer; it clears the user for data access (userid/password); it requires
 the user to specify the screening number of the subject about to be randomized; it verifies
 inclusion/exclusion criteria and acquires stratification information; it finally assigns the
 subject to a treatment, and delivers the corresponding unique randomization number. The
 procedure optimizes the overall balance of treatments among each stratification cell. The
 allocation algorithm will be verified by the responsible statistician for the study, who will
 have continuing access to the randomization statistics throughout the duration of the study.

 Criteria for discontinuation and/or withdrawal

 Criteria for discontinuation:

 -  Withdrawal of informed consent

 -  Subject uncooperative

 -  Safety reasons as judged by principal investigator

 -  Non-compliance to the protocol

 -  Incorrect enrolment

 -  Subjects who could not be operated laparoscopically

 -  Conditions requiring medication that could interfere with the outcome of the study
 except those for intercurrent illnesses or adjustment of anti-hypertensive therapy as
 judged by the principal investigator

 -  Subjects with severe complications due to the surgery as judged by the principal
 investigator

 -  Bleedings related to surgery that make it impossible to draw blood samples

 Subjects may be discontinued from the study at any time, at the discretion of the
 investigator. Subjects are free to discontinue their participation in the study at any time.
 Subjects who discontinue from the study should always be asked about the reason(s) for the
 discontinuation. If possible, they should always be seen and assessed by an investigator.
 Adverse events will be followed up according to national requirements.

 If a subject discontinues participation in the study, then his enrolment number cannot be
 issued to another subject.

 EFFICACY EVALUATION

 In order to evaluate the effect of the sleeve gastrectomy versus the Roux-en-Y Gastric bypass
 on the glycemic control the following parameters will be considered:

 Primary endpoint Primary Endpoint: incidence of reactive hypoglycemia at 1 year after the
 bariatric surgery.

 Secondary End-points

 -  Changes at 1 year of insulin sensitivity and insulin secretion measured by means of an
 OGTT.

 -  Changes at 1 year of body weight, BMI, abdominal circumference, body composition and
 lipid profile.

 -  the incidence of severe hypoglycemia or related symptoms (shakiness, sweating, dizziness
 or light-headedness, confusion, difficulty speaking, weakness, confusion, syncope,
 epilepsy, seizures) within 5 years after the operation.

 Evaluation methods and timing

 During the experimental study the following clinical evaluations will be performed:

 1. Demographic Data (week -18)

 -  Date of birth

 -  Gender

 -  Ethnicity

 2. Medical and Surgical History (week -18, week -4)

 3. Anthropometric measurements (week -18, week -4, month 1, 3, 6, 9 and 12)

 -  Body Weight (will be measured to the nearest 0.1 kg on a balanced beam scale in the
 morning before breakfast after a visit to the lavatory in their underwear's).

 -  Height (will be measured to the nearest 0.5 cm using a stadiometer)

 -  Waist circumference (will be measured at the part of the trunk midway between the
 most caudal part of the lateral costal arch and the iliac crest in the morning
 before breakfast, after lavatory visit with the person standing with feet about
 25-30 cm apart. The measurer will stand beside the individual and fit the tape
 snugly, without compressing any underlying soft tissues. The circumference will be
 measured to the nearest 0.5 cm, at the end of a normal expiration.

 -  Hip circumference (will be measured as the maximal circumference over the buttocks)

 -  BMI (will be computed as weight (kg) / height (m2))

 4. Physical examination (week -18, week -4, month 1, 3, 6, 9 and 12)

 -  General appearance

 -  Skin

 -  Head and neck

 -  Lymph nodes

 -  Thyroid

 -  Cardiovascular system

 -  Respiratory systems

 -  Abdomen

 -  Other

 5. Cardiovascular Parameters (week -18, week -4, month 1, 3, 6, 9 and 12)

 -  Blood pressure

 -  Heart rate (blood pressure and heart rate will be measured in sitting position in
 duplicate after 15 min rest)

 -  ECG (recorded under resting condition. It will be performed according to standard
 routine at bariatric surgery)

 6. Biochemical analysis (week -18, week -4, month 1, 3, 6, 9 and 12)

 -  Fasting plasma glucose

 -  Fasting plasma insulin

 -  Fasting plasma C-peptide

 -  HbA1c

 -  Total cholesterol

 -  HDL-cholesterol

 -  Triglycerides

 -  Hematology profile

 -  Chemistry panel

 7. Oral Glucose Tolerance Test (OGTT) (week -18, month 1, 3, 6, 9 and 12) At 8:00-9:00
 a.m., after a 12-h overnight fast, an intravenous catheter is placed in one antecubital
 vein to draw blood samples. An OGTT (75 g of glucose) is performed in 10 minutes maximum
 and blood samples obtained at -20, -5, 5, 10, 20, 30, 40, 60, 80, 100, 120, 140, 160 and
 180 min relative to the start of the OGTT. Samples are placed in chilled tubes, and
 plasma is separated within 20 min and stored at -70°C.

 Analytical Methods Plasma glucose will be measured by the glucose-oxidase method
 (Beckman, Fullerton, CA). Plasma insulin will be assayed by microparticle-enzyme
 immunoassay (Abbott, Pasadena, CA) with a sensitivity of 1 μU/ml and an intra-assay CV
 of 6.6%.

 C-peptide will be assayed by radioimmunoassay (MYRIA; Technogenetics, Milan, Italy):
 minimal detectable concentration =17 pmol/l and inter- and intra-assay CVs of 3.3-5.7
 and 4.6 -5.3, respectively.

 Mathematical modeling: to be detailed.

 8. DEXA variables (week -4, month 6, 9 and 12) (Body composition is measured by DEXA (Lunar
 Prodigy), which provides results on total and regional (trunk, arms, legs, pelvis) fat
 mass, fat free mass, and bone mass)

 -  Total body bone mineral density

 -  Lean body mass

 -  Fat mass

 -  Percent weight body fat

 9. Concomitant medication (week -18, week -4, month 1, 3, 6, 9 and 12)

 SAFETY AND TOLERANCE EVALUATION AND ASSESSMENT The safety of the surgical procedures will be
 evaluated at the end of the study analyzing all the information recorded in the Case Report
 Form suitably designed for the study, according to the timing and modalities described in
 other sections of the present protocol.

 Information to assess the safety will include: objective exam, patient's symptoms related to
 the operation, occurrence of adverse events.

 Safety parameters Adverse Events

 The clinical tolerability will be evaluated by recording of the occurrence of adverse events
 as reported by the patient or observed by the medical investigator. Any adverse event
 occurred after the surgical treatment will have to be recorded in the Case Report Form.

 Definitions

 An adverse event (AE) is any untoward medical occurrence in a patient or clinical
 investigation subject undergone a treatment and which does not necessarily have a causal
 relationship with this treatment. An AE can therefore be any unfavorable and unintended sign,
 symptom, or disease temporally associated with the use of a medicinal product, or related to
 the surgical procedure. Pre-existing events, which increase in frequency or severity, or
 change in nature during or as a consequence of use of a drug in human clinical trials, will
 also be considered as AEs.

 A serious adverse event (SAE) is defined as any adverse event regardless of causality that

 led to a death, led to a serious deterioration in the health of the subject that resulted in
 a life-threatening illness or injury, resulted in a permanent impairment of a body structure
 or a body function, required in-patient hospitalization or prolongation of existing
 hospitalization, results in medical or surgical intervention to prevent permanent impairment
 to body structure or a body function.

 led to fatal distress or fatal death.

 A serious adverse device effect (ADE) is a serious adverse event related to the adopted
 device (in the specific case the surgical procedures) that results in any of the consequences
 characteristic of a serious adverse event or that might led to any of these consequences if
 suitable action is not taken or intervention is not made or if circumstances are less
 opportune.

 Adverse Event and adverse device effect Reporting Procedures If the investigator identifies
 the occurrence of an AE, SAE or of an ADE report form must be completed and sent by fax to
 the Coordinating Investigator within 24 hours of the investigator's knowledge of the event.
 This form will be part of the study documentation. Any fatal or life-threatening event should
 be reported immediately to Coordinating Investigator by telephone. These preliminary reports
 will be followed within 24 hours by detailed descriptions that will include a completed
 SAE/ADE form, copies of hospital case reports, autopsy reports, and other documents, when
 requested and applicable.

 Minimal information should include:

 An identifiable subject or patient The type of surgical treatment the patient was undergone
 An identifiable reporting source All related adverse events All medications used Follow-up of
 SAE/ADEs that occur during the study will continue until satisfactory resolution or
 stabilization, with a maximum of six months, upon judgment of the investigator. The
 coordinating investigator may request that certain adverse events to be followed until
 resolution.

 If/ when supplementary information is available, a follow-up SAE/ADE Report Form must be
 completed by the investigator and delivered within 24 hours to the coordinating investigator.

 Once faxed, the SAE/ADE form and accompanying documentation should be placed in the SAE/ADE
 section of the investigator's file. If supplementary information on a SAE/ADE has to be sent,
 the SAE/ADE form has to be used marked as "follow-up report".

 The coordinating investigator must inform the Ethics Committee if the serious adverse event
 is likely to affect the safety of the subjects or the conduct of the study.

 Moreover will be responsibility of the Coordinating Investigator of informing in writing all
 clinical investigators about all serious adverse events and all serious adverse device
 effects occurring during the study. This information shall be sent to the clinical
 investigators based on perceived risk.

 DIRECT ACCESS TO ORIGINAL DOCUMENTATION The Investigator will have to allow the national
 Regulatory Authority, and the staff designed by the Independent Ethical Committee or by
 coordinating investigator direct access to the complete original documentation - and its
 verification - including informed consent, signed by the enrolled patients or by their Legal
 Representatives, and the clinical records or outpatient registers. People who have direct
 access to this documentation will have to take all reasonable precautions in order to
 maintain the patient identity and all information which is property of the Coordinating
 Investigator, in compliance with applicable laws.

 QUALITY ASSURANCE PROCEDURES The Organization, Monitoring and Quality Assurance of the
 present study will be under the responsibility of the Coordinating Investigator.

 Clinical Monitoring The clinical monitoring will be carried out by qualified persons assigned
 by the Coordinating Investigator and will be conducted according to the guidelines of the ISO
 Standard 14155-1. Additionally the monitoring activities will include the verification of the
 correct filling of the CRFs and, when applicable, the consistence between source documents
 and the electronic stored data used for the randomization procedures. The coordinating
 investigator will ensure the practical training for the personal involved in the study on the
 surgical and medical techniques and on filling the CRFs.

 Data Review and Audits Data Review and Audits will be carried out by qualified persons
 assigned by the Coordinating Investigator.

 The CRFs will be periodically reviewed. Financing of the study No financial aspect must be
 taken into account because no funding is foreseen for the present study.

 Table 1 Variables recorded during the Physical examination and included in DEXA

 PHYSICAL EXAMINATION Appearence general Skin Head and neck Lymph nodes Thyroid Cardiovascular
 system Respiratory systems Abdomen Concomitant medication Other DEXA Total body bone mineral
 density Lean body mass Fat mass Percent weight body fat
Inclusion Criteria:

 -  Patients are eligible if aged between 25 and 65 years, have a body mass index of 35
 (in presence of complications as sleep apnea, severe coxarthritis or gonarthritis,
 severe hypertension) to 50 kg/m2, and are able to understand and comply with the study
 process.

 Exclusion Criteria:

 -  History of type 1 diabetes or secondary diabetes;

 -  Previous bariatric surgery;

 -  History of medical problems such as mental impairment;

 -  Major cardiovascular disease;

 -  Major gastrointestinal disease;

 -  Major respiratory disease;

 -  Hormonal disorders;

 -  Infection;

 -  History of drug addiction and/or alcohol abuse;

 -  Internal malignancy;

 -  Pregnancy;

 -  Impaired glucose tolerance;

 -  Suspected or confirmed poor compliance;

 -  Informed consents.