Skeletal Health in Bariatric Surgery Patients

Study Overview
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Brief Summary
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The investigators propose a prospective cohort trial that will help to understand the impact of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) in pre- and post-menopausal female bariatric patients.

Detailed Description
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While highly effective both RYGB and SG may lead to increased bone resorption, decreased bone mass, and increased risk of some fractures. Very few studies have compared the effects of the RYGB and the SG on changes skeletal health and findings have been inconsistent. Furthermore, few studies have investigated the short- or long-term consequences of bariatric surgery on bone mineral density in pre- and post-menopausal women. To what extent and how bariatric surgery impacts the skeleton largely remains undetermined. Because estrogen is protective against osteoporosis and fractures, the majority of fractures occur in postmenopausal women. It is important that women have higher rates of obesity (38.3%) compared to men (34.3%) and that ≥67% of bariatric patients are women. Therefore, women may be at a significantly increased risk of developing osteoporosis. These data may help establish clinical guidelines to assess, maintain, and promote skeletal health in the preoperative and postoperative care of bariatric patients; and it may help to determine the appropriate bariatric procedure for women at risk of osteoporosis and fractures.

Official Title
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Skeletal Health in Bariatric Surgery Patients

Conditions
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Premenopause, Bariatric Surgery, Osteoporosis, Fractures, Bone, Roux En-Y Gastric Bypass, Sleeve Gastrectomy, Menopause

Intervention / Treatment
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* Procedure: Roux en Y Gastric Bypass Pre-menopausal
* Procedure: Roux en Y Gastric Bypass Post-menopausal
* Procedure: Sleeve Gastrectomy Pre-menopausal
* Procedure: Sleeve Gastrectomy Post-menopausal


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult females ≥ 19 years scheduled to undergo bariatric surgery (Roux en Y Gastric Bypass or Gastric Sleeve Surgery) Class II (BMI 35-39.9 kg/m2). Class III obesity (BMI ≥ 40 kg/m2). Scheduled to undergo bariatric surgery with the ability to provide informed consent. Exclusion Criteria: Patients with a history of thyroid disorders, thyroidectomy and levothyroxine use. Patients with a history of known osteoporosis, steroid-induced osteoporosis, current or previous use of medications for osteoporosis. Patients with a history of gastrointestinal malabsorption. Patients with a history of renal diseases. Patients with a history of current or previous use of corticosteroids. Patients who have used tobacco products within a year of study enrollment. Patients with surgically-induced menopause e.g. bilateral salpingo-oophorectomy. Patients with a history of breast cancer, who have had or are currently on hormonal therapy or anti-hormonal therapy.

Ages Eligible for Study
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Minimum Age: 19 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Roux en Y Gastric Bypass Pre-menopausal<br>Pre-menopausal women undergoing Roux en Y Gastric Bypass | Procedure: Roux en Y Gastric Bypass Pre-menopausal<br>* The investigator aims to determine changes in skeletal health after Roux en Y Gastric Bypass in pre-menopausal women. Dual-energy x-ray absorptiometry (DXA) will be used to assess bone mineral density (BMD), including assessment for fracture risk (FRAX). Trabecular Bone Score (TBS) software will be used to adjust FRAX scores for bone microstructure and an enhanced fracture risk probability. Biochemical markers of bone metabolism and calcium homeostasis including serum bone alkaline phosphatase (BALP), osteocalcin, type 1 procollagen (P1NP), c-terminal telopeptide (CTX), calcium, albumin, parathyroid hormone (PTH), and 25-OH vitamin D will be assayed.<br>|
| Roux en Y Gastric Bypass Post-menopausal<br>Post-menopausal women undergoing Roux en Y Gastric Bypass | Procedure: Roux en Y Gastric Bypass Post-menopausal<br>* The investigator aims to determine changes in skeletal health after Roux en Y Gastric Bypass in post-menopausal women. Dual-energy x-ray absorptiometry (DXA) will be used to assess bone mineral density (BMD), including assessment for fracture risk (FRAX). Trabecular Bone Score (TBS) software will be used to adjust FRAX scores for bone microstructure and an enhanced fracture risk probability. Biochemical markers of bone metabolism and calcium homeostasis including serum bone alkaline phosphatase (BALP), osteocalcin, type 1 procollagen (P1NP), c-terminal telopeptide (CTX), calcium, albumin, parathyroid hormone (PTH), and 25-OH vitamin D will be assayed.<br>|
| Sleeve Gastrectomy Pre-menopausal<br>Pre-menopausal women undergoing Sleeve Gastrectomy | Procedure: Sleeve Gastrectomy Pre-menopausal<br>* The investigator aims to determine changes in skeletal health after Sleeve Gastrectomy in pre-menopausal women. Dual-energy x-ray absorptiometry (DXA) will be used to assess bone mineral density (BMD), including assessment for fracture risk (FRAX). Trabecular Bone Score (TBS) software will be used to adjust FRAX scores for bone microstructure and an enhanced fracture risk probability. Biochemical markers of bone metabolism and calcium homeostasis including serum bone alkaline phosphatase (BALP), osteocalcin, type 1 procollagen (P1NP), c-terminal telopeptide (CTX), calcium, albumin, parathyroid hormone (PTH), and 25-OH vitamin D will be assayed.<br>|
| Sleeve Gastrectomy Post-menopausal<br>Post-menopausal women undergoing Gastric Sleeve | Procedure: Sleeve Gastrectomy Post-menopausal<br>* The investigator aims to determine changes in skeletal health after Sleeve Gastrectomy in post-menopausal women. Dual-energy x-ray absorptiometry (DXA) will be used to assess bone mineral density (BMD), including assessment for fracture risk (FRAX). Trabecular Bone Score (TBS) software will be used to adjust FRAX scores for bone microstructure and an enhanced fracture risk probability. Biochemical markers of bone metabolism and calcium homeostasis including serum bone alkaline phosphatase (BALP), osteocalcin, type 1 procollagen (P1NP), c-terminal telopeptide (CTX), calcium, albumin, parathyroid hormone (PTH), and 25-OH vitamin D will be assayed.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determine and quantify changes in bone mineral density after bariatric surgery (Roux en Y vs. Gastric Sleeve) in pre- and post-menopausal women. | Dual-energy x-ray absorptiometry (DXA) will be used to assess bone mineral density, BMD (in g/cm2) of the lumbar spine (L1-L4), total hip, femoral neck, distal radius, sub-total whole body (excluding only the head), and whole body. T scores will be evaluated and Z scores will be evaluated. T-scores between +1 and -1 is considered normal or healthy, T-scores between -1 and -2.5 indicates that you have low bone mass, although not low enough to be diagnosed with osteoporosis, T-scores of -2.5 or lower indicates that you have osteoporosis. For premenopausal women under the age of 50, the Z-score is used for diagnosis. Using the criteria defined by the International Society for Clinical Densitometry: If the Z-score is -2.0 or lower, the result will be below the expected range for age. If the Z score is above -2.0, the result is will be defined as within the expected range for age. | Baseline | 
| Determine and quantify changes in bone mineral density after bariatric surgery (Roux en Y vs. Gastric Sleeve) in pre- and post-menopausal women. | Dual-energy x-ray absorptiometry (DXA) will be used to assess bone mineral density, BMD (in g/cm2) of the lumbar spine (L1-L4), total hip, femoral neck, distal radius, sub-total whole body (excluding only the head), and whole body. T scores will be evaluated and Z scores will be evaluated. T-scores between +1 and -1 is considered normal or healthy, T-scores between -1 and -2.5 indicates that you have low bone mass, although not low enough to be diagnosed with osteoporosis, T-scores of -2.5 or lower indicates that you have osteoporosis. For premenopausal women under the age of 50, the Z-score is used for diagnosis. Using the criteria defined by the International Society for Clinical Densitometry: If the Z-score is -2.0 or lower, the result will be below the expected range for age. If the Z score is above -2.0, the result is will be defined as within the expected range for age. | Baseline to 12 months | 
| Determine and quantify changes in bone mineral density after bariatric surgery (Roux en Y vs. Gastric Sleeve) in pre- and post-menopausal women. | Dual-energy x-ray absorptiometry (DXA) will be used to assess bone mineral density, BMD (in g/cm2) of the lumbar spine (L1-L4), total hip, femoral neck, distal radius, sub-total whole body (excluding only the head), and whole body. T scores will be evaluated and Z scores will be evaluated. T-scores between +1 and -1 is considered normal or healthy, T-scores between -1 and -2.5 indicates that you have low bone mass, although not low enough to be diagnosed with osteoporosis, T-scores of -2.5 or lower indicates that you have osteoporosis. For premenopausal women under the age of 50, the Z-score is used for diagnosis. Using the criteria defined by the International Society for Clinical Densitometry: If the Z-score is -2.0 or lower, the result will be below the expected range for age. If the Z score is above -2.0, the result is will be defined as within the expected range for age. | Baseline to 24 months | 
| Fracture risk assessment in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | Assessment of fracture risk using the WHO Fracture Risk Assessment Tool (FRAX) will be used to assess the 10-year fracture risk probability (in %) | Baseline | 
| Fracture risk assessment in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | Assessment of fracture risk using the WHO Fracture Risk Assessment Tool (FRAX) will be used to assess the 10-year fracture risk probability (in %) | Baseline to 12 months | 
| Fracture risk assessment in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | Assessment of fracture risk using the WHO Fracture Risk Assessment Tool (FRAX) will be used to assess the 10-year fracture risk probability (in %) | Baseline to 24 months | 
| TBS adjustment of FRAX scores for an enhanced fracture risk probability in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | The Trabecular Bone Score (TBS) is derived from the texture of the DXA image and has been shown to be related to fracture risk. Trabecular Bone Score (TBS) software will be used to adjust fracture risk (FRAX) scores to obtain TBS scores (in gradient risk). FRAX adjusted TBS scores (in gradient of risk) ranges from 1.1% -1.9% coefficient of variation (C.V.) | Baseline | 
| TBS adjustment of FRAX scores for an enhanced fracture risk probability in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | The Trabecular Bone Score (TBS) is derived from the texture of the DXA image and has been shown to be related to fracture risk. Trabecular Bone Score (TBS) software will be used to adjust fracture risk (FRAX) scores to obtain TBS scores (in gradient risk). FRAX adjusted TBS scores (in gradient of risk) ranges from 1.1% -1.9% coefficient of variation (C.V.) | Change from baseline to 12 months | 
| TBS adjustment of FRAX scores for an enhanced fracture risk probability in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | The Trabecular Bone Score (TBS) is derived from the texture of the DXA image and has been shown to be related to fracture risk. Trabecular Bone Score (TBS) software will be used to adjust fracture risk (FRAX) scores to obtain TBS scores (in gradient risk). FRAX adjusted TBS scores (in gradient of risk) ranges from 1.1% -1.9% coefficient of variation (C.V.) | Change from baseline to 24 months | 
| TBS assessment of bone microstructure in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | The Trabecular Bone Score (TBS) is derived from the texture of the DXA image and has been shown to be related to bone microarchitecture. Trabecular Bone Score (TBS) software will be used to assess bone microstructure. TBS ≤1.2 defines degraded microarchitecture, TBS between 1.20 and 1.35 is partially degraded microarchitecture, and TBS ≥1.35 is considered normal. | Baseline | 
| TBS assessment of bone microstructure in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | The Trabecular Bone Score (TBS) is derived from the texture of the DXA image and has been shown to be related to bone microarchitecture. Trabecular Bone Score (TBS) software will be used to assess bone microstructure. TBS ≤1.2 defines degraded microarchitecture, TBS between 1.20 and 1.35 is partially degraded microarchitecture, and TBS ≥1.35 is considered normal. | Change from baseline to 12 months | 
| TBS assessment of bone microstructure in pre and post-menopausal women undergoing bariatric surgery (Roux en Y vs. Gastric Sleeve). | The Trabecular Bone Score (TBS) is derived from the texture of the DXA image and has been shown to be related to bone microarchitecture. Trabecular Bone Score (TBS) software will be used to assess bone microstructure. TBS ≤1.2 defines degraded microarchitecture, TBS between 1.20 and 1.35 is partially degraded microarchitecture, and TBS ≥1.35 is considered normal. | Change from baseline to 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Serum bone alkaline phosphatase (BALP in U/L) will be assayed | Baseline | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Serum bone alkaline phosphatase (BALP in U/L) will be assayed | Baseline to 6 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Serum bone alkaline phosphatase (BALP in U/L) will be assayed | Baseline to 12 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Serum bone alkaline phosphatase (BALP in U/L) will be assayed | Baseline to 24 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Osteocalcin (in ng/mL) will be assayed. | Baseline | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Osteocalcin (in ng/mL) will be assayed. | Baseline to 6 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Osteocalcin (in ng/mL) will be assayed. | Baseline to 12 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Osteocalcin (in ng/mL) will be assayed. | Baseline to 24 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Type 1 procollagen (P1NP, in mcg/L) will be assayed. | Baseline | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Type 1 procollagen (P1NP, in mcg/L) will be assayed. | Baseline to 6 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Type 1 procollagen (P1NP, in mcg/L) will be assayed. | Baseline to 12 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Type 1 procollagen (P1NP, in mcg/L) will be assayed. | Baseline to 24 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | C-terminal telopeptide (CTX, in pg/mL) will be assayed. | Baseline | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | C-terminal telopeptide (CTX, in pg/mL) will be assayed. | Baseline to 6 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | C-terminal telopeptide (CTX, in pg/mL) will be assayed. | Baseline to 12 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | C-terminal telopeptide (CTX, in pg/mL) will be assayed. | Baseline to 24 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Calcium (in mg/dL), albumin (in, g/dL) will be assayed. | Baseline | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Calcium (in mg/dL), albumin (in, g/dL) will be assayed. | Baseline to 6 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Calcium (in mg/dL), albumin (in, g/dL) will be assayed. | Baseline to 12 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Calcium (in mg/dL), albumin (in, g/dL) will be assayed. | Baseline to 24 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Parathyroid hormone (PTH, in pg/mL) will be assayed. | Baseline | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Parathyroid hormone (PTH, in pg/mL) will be assayed. | Baseline to 6 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Parathyroid hormone (PTH, in pg/mL) will be assayed. | Baseline to 12 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | Parathyroid hormone (PTH, in pg/mL) will be assayed. | Baseline to 24 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | 25-OH vitamin D (in ng/mL) will be assayed. | Baseline | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | 25-OH vitamin D (in ng/mL) will be assayed. | Baseline to 6 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | 25-OH vitamin D (in ng/mL) will be assayed. | Baseline to 12 months | 
| Determine and quantify changes in biochemical markers of bone metabolism and calcium homeostasis. | 25-OH vitamin D (in ng/mL) will be assayed. | Baseline to 24 months |