Clinical trial NCT01330914: Effects of Gastric Bypass Surgery and Calcium Metabolism and the Skeleton
Official title: Effects of Gastric Bypass Surgery on Calcium Metabolism and the Skeleton
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Obesity, Morbid
Gastric Bypass
Keywords: Obesity, Morbid
Bariatric Surgery
Gastric Bypass
Calcium Metabolism Disorders
Vitamin D
Bone Density
Body Composition
Weight Loss
Lead sponsor: VA Office of Research and Development
Sponsor class: FED
First posted: 2011-04-07
Enrollment: 55
Sex: ALL
Minimum age (years): 25
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Men and women 25 to 70 years old scheduled to undergo gastric bypass surgery

Brief summary: Obesity is a chronic illness of staggering proportions. Because weight loss through diet and exercise is difficult to attain and maintain, there has been escalating interest in bariatric surgery, including Roux-en-Y gastric bypass. Gastric bypass surgery results in long-term weight loss, dramatic improvement in comorbidities such as diabetes, and decreased mortality. Emerging evidence suggests, however, that gastric bypass may have negative effects on bone health. Because of the serious consequences of osteoporosis and fracture, this is of great concern. This study of the effects of gastric bypass on calcium metabolism and the skeleton may positively impact the clinical care of gastric bypass patients by their surgeons, primary care providers, and endocrinologists. Further, the knowledge gained may inform future investigation into the relationships between obesity, weight loss, and bone biology.


Eligibility criteria: Inclusion Criteria:

Scheduled to undergo gastric bypass surgery. Please note that to be eligible, one must already be working with a bariatric surgeon and with plans in place to undergo gastric bypass. This study is unable to arrange or pay for gastric bypass surgery.

Exclusion Criteria:

* Perimenopausal women
* Known intestinal malabsorption
* Prior bariatric surgery
* Use of medications known to impact bone and mineral metabolism
* Disease known to affect bone
* Illicit drug use or alcohol use \>3 drinks/day
* Serum calcium \>10.2 mg/dL
* Calculated creatinine clearance \<30 mL/min
* Weight \>350 pounds
* Wrist circumference \>12 inches or calf circumference \>17 inches

Primary outcomes:
measure: Change in Intestinal Calcium Absorption
timeFrame: 6 months (between baseline and 6 months)
Secondary outcomes:
measure: Areal Bone Mineral Density (BMD) at the Femoral Neck
timeFrame: 12 months post-operatively (between baseline and 12 months)
measure: Trabecular Number at the Tibia
timeFrame: 12 months post-operatively (between baseline and 12 months)
Other outcomes:
Locations:
city: San Francisco
country: United States
facility: San Francisco VA Medical Center, San Francisco, CA
state: California
Study officials:
affiliation: San Francisco VA Medical Center, San Francisco, CA
name: Anne L Schafer, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Schafer AL, Weaver CM, Black DM, Wheeler AL, Chang H, Szefc GV, Stewart L, Rogers SJ, Carter JT, Posselt AM, Shoback DM, Sellmeyer DE. Intestinal Calcium Absorption Decreases Dramatically After Gastric Bypass Surgery Despite Optimization of Vitamin D Status. J Bone Miner Res. 2015 Aug;30(8):1377-85. doi: 10.1002/jbmr.2467. Epub 2015 May 21.
citation: Schafer AL, Li X, Schwartz AV, Tufts LS, Wheeler AL, Grunfeld C, Stewart L, Rogers SJ, Carter JT, Posselt AM, Black DM, Shoback DM. Changes in vertebral bone marrow fat and bone mass after gastric bypass surgery: A pilot study. Bone. 2015 May;74:140-5. doi: 10.1016/j.bone.2015.01.010. Epub 2015 Jan 17.