Clinical trial NCT02169050: Association Between Vitamin D and Inflammation and Diabetes Risk in Morbidly Obese Pre-Menopausal Women
Official title: Vitamin D, Inflammation, and Relations to Insulin Resistance in Morbidly Obese Pre-Menopausal Women
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Insulin Sensitivity
Keywords: Vitamin D deficiency
Inflammation
Obesity
Lead sponsor: University of Illinois at Chicago
Sponsor class: OTHER
First posted: 2014-06-20
Enrollment: 76
Sex: FEMALE
Minimum age (years): 21
Maximum age (years): 49
Standard ages: ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Study subjects are drawn from women seeking surgical treatment for their morbid obesity at the University of Illinois at Chicago Medical Center (UICMC) Bariatric surgery clinics.

Brief summary: Obesity is associated with low-grade inflammation, insulin resistance and low vitamin D status. Vitamin D has traditionally been known to involve in calcium homeostasis and prevent rickets; however, recently it has been recognized to inversely associate with many non-skeletal diseases and conditions including obesity and type 2 diabetes (T2DM). In vitro studies have demonstrated that vitamin D possesses anti-inflammatory properties. It remains unknown if the effect of vitamin D on insulin sensitivity is mediated by suppressing inflammation in human adipose tissues. The main objective of this study was to assess the association between vitamin D and insulin sensitivity and inflammation in morbidly obese pre-menopausal women. Obese women (n=76) were recruited from the University of Illinois at Chicago (UIC) Nutrition and Wellness Center and the UIC medical center bariatric surgery clinics. Insulin sensitivity/resistance was assessed by (1) Oral glucose insulin sensitivity (OGIS) index, derived from dynamic oral glucose tolerance test (OGTT), and (2) Homeostasis model of insulin resistance (HOMA-IR), calculated from fasting steady-state glucose and insulin. Also, to better understand the potential mechanism and the role circulating vitamin D (25OHD) plays in adipose tissue inflammation, we assessed messenger ribonucleic acid (mRNA) expression of vitamin D receptor (VDR) and various inflammatory genes in visceral (VAT) and subcutaneous adipose tissues (SAT) of obese women that underwent a restrictive bariatric procedure. We hypothesized that subjects with higher serum vitamin D levels would be less inflamed and more insulin sensitive and have increased expression of VDR and pro-inflammatory markers compared to those with lower serum vitamin D levels.


Eligibility criteria: Inclusion Criteria:

* Premenopausal women between the age of 21 and 49 years old
* BMI \>=35(kg/m2)
* Not pregnant
* English speaking
* Approved for a bariatric surgery

Exclusion Criteria:

Subjects with:

* Diabetes
* Cancer
* Kidney disease
* Liver disease
* Gallbladder disease
* Rheumatoid arthritis
* HIV/AIDS
* Crohn's disease or inflammatory bowel disease
* Subjects taking anti-inflammatory medications

Primary outcomes:
measure: Oral Glucose Insulin Sensitivity (OGIS)
timeFrame: 2 hour, 1-5 weeks before bariatric surgery
Secondary outcomes:
measure: Adipose tissue mRNA Expression of Vitamin D Receptors and Inflammation Markers
timeFrame: 10-20 minutes, during bariatric surgery
measure: Inflammatory markers in plasma
timeFrame: 3-15 minutes, 1-5 weeks before bariatric surgery
Other outcomes:
Locations:
city: Chicago
country: United States
facility: University of Illinois at Chicago
state: Illinois
Study officials:
affiliation: University of Illinois at Chicago
name: Carol Braunschweig, PhD
role: PRINCIPAL_INVESTIGATOR
References: