An observational study in Obesity, Morbid and Gastric Bypass, sponsored by VA Office of Research and Development. Completed at 1 site in United States. Open to participants aged 25 Years to 70 Years. Per ClinicalTrials.gov, last updated 2019-03-15.
Sponsored by VA Office of Research and Development · Observational
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.
922 studies on the registry are indexed under Obesity, Morbid; 172 are open to participants now.
This study's enrollment of 55 is below the median of 78 across 306 observational studies indexed under Obesity, Morbid.
Browse Obesity, Morbid studies →VA Office of Research and Development is the lead sponsor of 1,733 studies on the registry; 396 are open to participants now.
Of its 206 completed or terminated interventional studies of FDA-regulated products, 180 (87%) have results posted.
Counted across the registry records on this site, refreshed daily.
Men and women 25 to 70 years old scheduled to undergo gastric bypass surgery
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:
Obese men and women undergoing gastric bypass surgery
Change in Intestinal Calcium Absorption
Change in fractional calcium absorption, determined by dual stable isotope method. Fractional calcium absorption is the fraction of ingested calcium that is absorbed, which is expressed here as the percentage of ingested calcium that is absorbed. The 6-month change is the mean difference in percentage absorption between time points. For example, if fractional calcium absorption were to decrease from 30% preoperatively to 25% at the 6-month postoperative time point, the change in fractional calcium absorption would be -5%.
Time frame: 6 months (between baseline and 6 months)
Areal Bone Mineral Density (BMD) at the Femoral Neck
Areal BMD at the femoral neck by dual-energy X-ray absorptiometry (DXA). The 12-month change is the percentage change between the 12 month and baseline time points.
Time frame: 12 months post-operatively (between baseline and 12 months)
Trabecular Number at the Tibia
Trabecular number at the tibia by high-resolution peripheral quantitative computed tomography (HR-pQCT). The 12-month change is the percentage change between the 12 month and baseline time points. HR-pQCT images were analyzed using the manufacturer's standard clinical evaluation protocol, with trabecular structure extracted using a threshold-based binarization process.
Time frame: 12 months post-operatively (between baseline and 12 months)
Women and men 25-70 years of age were recruited from two academic bariatric surgery centers (the University of California, San Francisco and the San Francisco Veterans Affairs Medical Center), where surgeons used the same standardized surgical approach to Roux-en-Y gastric bypass.
| Milestone | Gastric Bypass Surgery Patients |
|---|---|
| Started | 55 |
| Completed | 48 |
| Not completed | 7 |
| Withdrew: Withdrawal by subject | 4 |
| Withdrew: No longer eligible (sleeve gastrectomy) | 3 |
Change in fractional calcium absorption, determined by dual stable isotope method. Fractional calcium absorption is the fraction of ingested calcium that is absorbed, which is expressed here as the percentage of ingested calcium that is absorbed. The 6-month change is the mean difference in percentage absorption between time points. For example, if fractional calcium absorption were to decrease from 30% preoperatively to 25% at the 6-month postoperative time point, the change in fractional calcium absorption would be -5%.
| % of ingested calcium that is absorbed | Gastric Bypass Surgery Patients |
|---|---|
| Change in Intestinal Calcium Absorption | -25.8 ± 15.3 |
Areal BMD at the femoral neck by dual-energy X-ray absorptiometry (DXA). The 12-month change is the percentage change between the 12 month and baseline time points.
| percent of baseline value | Gastric Bypass Surgery Patients |
|---|---|
| Areal Bone Mineral Density (BMD) at the Femoral Neck | -8.0 ± 4.9 |
Trabecular number at the tibia by high-resolution peripheral quantitative computed tomography (HR-pQCT). The 12-month change is the percentage change between the 12 month and baseline time points. HR-pQCT images were analyzed using the manufacturer's standard clinical evaluation protocol, with trabecular structure extracted using a threshold-based binarization process.
| percent of baseline value | Gastric Bypass Surgery Patients |
|---|---|
| Trabecular Number at the Tibia | -4.6 ± 8.4 |
Collected over 12 months. Non-serious events are listed at a 1.82% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Gastric Bypass Surgery Patients | — | 1/55 (1.8%) | 3/55 (5.5%) |
| Event | Gastric Bypass Surgery Patients |
|---|---|
| NephrolithiasisRenal and urinary disorders | 1/55 |
| Event | Gastric Bypass Surgery Patients |
|---|---|
| DyspepsiaGastrointestinal disorders | 2/55 |
| ConstipationGastrointestinal disorders | 1/55 |
| NephrolithiasisRenal and urinary disorders | 1/55 |
| Age, Continuous(years) | Gastric Bypass Surgery Patients |
|---|---|
| Mean | 45.8 ± 11.2 |
| Sex: Female, Male(Participants) | Gastric Bypass Surgery Patients |
|---|---|
| Female | 44 |
| Male | 11 |
| Ethnicity (NIH/OMB)(Participants) | Gastric Bypass Surgery Patients |
|---|---|
| Hispanic or Latino | 6 |
| Not Hispanic or Latino | 49 |
| Unknown or Not Reported | 0 |
| Race (NIH/OMB)(Participants) | Gastric Bypass Surgery Patients |
|---|---|
| American Indian or Alaska Native | 1 |
| Asian | 3 |
| Native Hawaiian or Other Pacific Islander | 2 |
| Black or African American | 12 |
| White | 37 |
| More than one race | 0 |
| Unknown or Not Reported | 0 |
| Region of Enrollment(participants) | Gastric Bypass Surgery Patients |
|---|---|
| United States | 55 |
| Menopausal status(participants) | Gastric Bypass Surgery Patients |
|---|---|
| Premenopausal | 30 |
| Postmenopausal | 14 |
| N/A (Men) | 11 |
| Weight(kg) | Gastric Bypass Surgery Patients |
|---|---|
| Mean | 122.7 ± 19.3 |
| Body mass index(kg/m2) | Gastric Bypass Surgery Patients |
|---|---|
| Mean | 44.2 ± 7.0 |
4 further baseline measures are reported on the registry.
This study is completed, as verified in Feb 2019. You cannot join it, but the record below documents what was studied.
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