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CompletedNCT01330251Updated Nov 1, 2017

The Effect of Gastric Bypass Surgery on Diabetes

An observational study in Type II Diabetes, sponsored by University of Oulu. Completed at 1 site in Finland. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2017-11-01.

Sponsored by University of Oulu · Observational

Study type
Observational
Model
Case-control
Time perspective
Prospective
Enrollment
41
Ages
18 Years to 65 Years
Sex
All
01

Study summary

This study will investigate the effects of gastric bypass surgery on type II diabetes. The study will recruit patients with type II diabetes having Roux-en-Y gastric bypass, patients without type II diabetes having Roux-en-Y gastric bypass, and control subjects (patients having gastroscopy, but no surgery). Targeted enrollment is 30 patients per group. Samples of intestine are taken prior to surgery in gastroscopy, during surgery, and 6 months after surgery during gastroscopy. Meal test with incretin measurements, and feces and blood samplings are performed before and after surgery

Hypotheses are:

  • The pathogenesis of type II diabetes is linked to changes in the expression of intestinal endocrine cells
  • The changes in the incretine excretion after the gastric bypass surgery partly explain the amelioration of type II diabetes
  • The oxidation of lipoprotein is diminished after the gastric bypass surgery slowing the development of atherosclerosis
  • The immunologic functions of the intestine are changed by the gastric bypass surgery attenuating systemic inflammation
  • The gastric bypass surgery changes cholesterol and bile acid metabolism
  • The gastric bypass surgery changes the fecal microbiota

Primary end points are:

  • Changes in the amounts of endocrine cells in ventricle, duodenum and jejunum
  • Changes in the incretine secretion studied with liquid meal test
  • Changes in the oxidation of lipoproteins
  • Changes in the immunologic markers in ventricle, duodenum and jejunum
  • Changes in the amounts of phytosterols, cholesterol metabolites and bile acids
  • Changes in fecal microbiota
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Conditions studied

  • Type II Diabetes
03

In context

Diabetes Mellitus, Type 2

9,589 studies on the registry are indexed under Diabetes Mellitus, Type 2; 1,332 are open to participants now.

This study's enrollment of 41 is below the median of 300 across 1,622 observational studies indexed under Diabetes Mellitus, Type 2.

Browse Diabetes Mellitus, Type 2 studies →

Lead sponsor

University of Oulu is the lead sponsor of 141 studies on the registry; 22 are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Non-probability sample

Study population

All patients are recruited from Oulu University Hospital

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Patients having Roux-en-Y gastric bypass (according to clinical guidelines)
  • Age: 18-65 years

Inclusion Criteria (control patients without surgery):

  • Patients having gastroscopy (for various clinical reasons)

Exclusion criteria

Exclusion Criteria:

  • Diabetes (applies for control patients)
  • BMI over 30 (applies for control patients)
  • Insulin treatment
  • Oral corticosteroid treatment
  • Chronic inflammatory disease
  • Coeliac disease
  • Malignant disease
05

Study design

Observational model
Case-control
Time perspective
Prospective
Enrollment
41 participants (actual)
Biospecimen retention
Samples with dna

Groups and cohorts

  • Patients with diabetes having Roux-en-Y gastric bypass
  • Patients without diabetes having Roux-en-Y gastric bypass
  • Control subjects (patients having gastroscopy, no surgery)
06

What researchers measure

Primary outcomes

  1. Changes in the amounts of endocrine cells in ventricle, duodenum and jejunum

    Samples of intestine are taken prior to surgery in gastroscopy, during surgery, and 6 months after surgery during gastroscopy

    Time frame: baseline to 6 months

  2. Changes in the incretine secretion studied with liquid meal test

    Samples of intestine are taken prior to surgery in gastroscopy, during surgery, and 6 months after surgery during gastroscopy

    Time frame: baseline to 6 months

  3. Changes in the oxidation of lipoproteins

    Samples of intestine are taken prior to surgery in gastroscopy, during surgery, and 6 months after surgery during gastroscopy

    Time frame: baseline to 6 months

  4. Changes in the immunologic markers in ventricle, duodenum and jejunum

    Samples of intestine are taken prior to surgery in gastroscopy, during surgery, and 6 months after surgery during gastroscopy

    Time frame: baseline to 6 months

  5. Changes in the amounts of phytosterols, cholesterol metabolites and bile acids

    Samples of intestine are taken prior to surgery in gastroscopy, during surgery, and 6 months after surgery during gastroscopy

    Time frame: baseline to 6 months

  6. Changes in fecal microbiota

    Samples of intestine are taken prior to surgery in gastroscopy, during surgery, and 6 months after surgery during gastroscopy

    Time frame: baseline to 6 months

07

Study locations

1 site
  • Oulu University Hospital
    Oulu, 90220, Finland
08

References and documents

Publications

  • Rahunen R, Merikallio H, Rinne V, Savolainen MJ, Hukkanen J. Hypertension in Overweight and Obesity: Sex-Specific Role of 4beta-Hydroxycholesterol. J Am Heart Assoc. 2026 Mar 3;15(5):e043913. doi: 10.1161/JAHA.125.043913. Epub 2026 Feb 26. PubMed 41744113 ↗
  • Zhao S, Horkko S, Savolainen MJ, Koivukangas V, Makinen VP, Ala-Korpela M, Hukkanen J. Short-Term Metabolic Changes and Their Physiological Mediators in the Roux-en-Y Gastric Bypass Bariatric Surgery. Obes Surg. 2024 Feb;34(2):625-634. doi: 10.1007/s11695-023-07042-y. Epub 2024 Jan 9. PubMed 38191968 ↗
  • Rahunen R, Kummu O, Koivukangas V, Hautajarvi H, Hakkola J, Rysa J, Hukkanen J. Pregnane X Receptor-4beta-Hydroxycholesterol Axis in the Regulation of Overweight- and Obesity-Induced Hypertension. J Am Heart Assoc. 2022 Mar 15;11(6):e023492. doi: 10.1161/JAHA.121.023492. Epub 2022 Mar 1. PubMed 35229613 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Nov 1, 2017, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT01330251
Lead sponsor
University of Oulu
Collaborators
Oulu University Hospital
Responsible party
Sponsor
First posted
Apr 6, 2011
Start date
Jan 2011
Primary completion
Dec 2016
Completion
Dec 2016
Last update
Nov 1, 2017

Study contacts

Vesa Koivukangas, MD, PhD
principal investigator · Oulu University Hospital

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Oct 2017. You cannot join it, but the record below documents what was studied.

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