Healthy Body, Healthy Bones After Bariatric Surgery Trial

One in three adults in the United States suffers from obesity. Bariatric surgery is an increasingly utilized and effective treatment for obesity and obesity-related comorbidities, however, the massive weight loss associated with bariatric surgery adversely affects bone metabolism. Significant decreases in bone mineral density lead to an increased risk of fracture and subsequent reduction in physical function among bariatric surgery patients. Bisphosphonate medications, such as zoledronic acid, have been evaluated for safety and efficacy in combating bone loss in patients with osteoporosis, but their use in bariatric surgery-induced bone loss has not been explored. The primary goal of this study is to investigate whether bisphosphonate therapies are able to combat bone loss associated with surgical weight loss procedures. This research proposal is a 1-year, pilot randomized controlled trial (RCT) involving 30 adult sleeve gastrectomy patients randomized to receive either a one-time zoledronic acid infusion or placebo (n=15 per group). The investigators hypothesize that zoledronic acid, a standard treatment for low bone density, will be an effective intervention to reduce sleeve gastrectomy-induced bone loss. Bone loss is an unintended consequence of an otherwise life-saving procedure, with declining bone health potentially contributing to major morbidity in those undergoing a bariatric procedure. Identifying effective interventions to minimize bone loss is crucial for comprehensive treatment of patients who undergo bariatric surgery. Specific Aim 1: To determine the efficacy of zoledronic acid in preventing bone loss associated with sleeve gastrectomy (SG). Bone mineral density (BMD) and bone turnover markers will be measured at baseline and 9 months. The primary outcome is change in BMD as measured by Dual-energy x-ray absorptiometry (DXA). Secondary outcomes are change in BMD as measured by Quantitative Computed Tomography (QCT) and change in the serum bone turnover markers, urinary collagen type 1 cross-linked N-telopeptide (CTX; bone formation marker), serum type 1 procollagen N-terminal (P1NP; bone resorption marker), sclerostin, and osteocalcin. Specific Aim 2: To evaluate the feasibility of this trial in those who have undergone SG surgery. The feasibility will be assessed by documenting adverse events and compliance rates of the intervention at each study time point.

Inclusion criteria

• Subjects planning a sleeve gastrectomy procedure at the University of Nebraska Medical Center (UNMC) Bariatric Center
• Agreement to all study procedures and assessments
• Women must be postmenopausal (FSH blood level > 30 mIU/m), or incapable of child-bearing

Exclusion criteria

• Prior bariatric surgery
• < 19 years of age
• Weight ≥ 350lbs
• Liver or renal disease
• Hypercalcemia, hypocalcemia, or hypomagnesemia
• Serum 25-OH vitamin D < 20 ng/mL
• History of bone-modifying disorders
• Use of bone-active medications
• Known sensitivity to bisphosphonates
• Extensive dental work involving extraction or dental implant within the past 2 months or planned in the upcoming 6 months
• Current diagnosis of type 1 diabetes
• Current malignancy
• Autoimmune disease impacting bone (ex: Rheumatoid Arthritis)