Bone Response to Weight Loss Following Bariatric Surgery

Abstract

Obesity is a global health challenge that warrants effective treatments to avoid its multiple comorbidities. Bariatric surgery, a cornerstone treatment to control bodyweight excess and relieve the health-related burdens of obesity, can promote accelerated bone loss and affect skeletal strength, particularly after malabsorptive and mixed surgical procedures, and probably after restrictive surgeries. The increase in bone resorption markers occurs early and persist for up to 12 months or longer after bariatric surgery, while bone formation markers increase but to a lesser extent, suggesting a potential uncoupling process between resorption and formation. The skeletal response to bariatric surgery, as investigated by dual-energy X-ray absorptiometry (DXA), has shown significant loss in bone mineral density (BMD) at the hip with less consistent results for the lumbar spine. Supporting DXA studies, analyses by high-resolution peripheral quantitative computed tomography (HR-pQCT) showed lower cortical density and thickness, higher cortical porosity, and lower trabecular density and number for up to 5 years after bariatric surgery. These alterations translate into an increased risk of fall injury, which contributes to increase the fracture risk in patients who have been subjected to bariatric surgery procedures. As bone deterioration continues for years following bariatric surgery, the fracture risk does not seem to be dependent on acute weight loss but, rather, is a chronic condition with an increasing impact over time. Among the post-bariatric surgery mechanisms that have been claimed to act globally on bone health, there is evidence that micro- and macro-nutrient malabsorptive factors, mechanical unloading and changes in molecules partaking in the crosstalk between adipose tissue, bone and muscle may play a determining role. Given these circumstances, it is conceivable that bone health should be adequately investigated in candidates to bariatric surgery through bone-specific work-up and dedicated postsurgical follow-up. Specific protocols of nutrients supplementation, motor activity, structured rehabilitative programs and, when needed, targeted therapeutic strategies should be deemed as an integral part of post-bariatric surgery clinical support.

Trabecular Bone Score Preceding and during a 2-Year Follow-Up after Sleeve Gastrectomy: Pitfalls and New Insights

“…We previously reported a decrease in total hip BMD but a stable LS BMD at 1 and 2 years after SG [12], compatible with the literature showing a consistent decrease in total hip BMD but not in LS BMD after bariatric surgery [7]. The impact of BS on bone microarchitecture has scarcely been evaluated, and few data have been published concerning the use of TBS in this context, despite it being a simple way to capture microarchitectural changes not seen in BMD.…”

“…Osteoporosis is associated with an increased risk of fractures due to the loss of bone strength secondary to low bone mineral density (BMD) and/or microarchitectural abnormalities [5,6]. Both these components of bone strength are impacted by bariatric surgery [7]. BMD, as evaluated via dual-energy X-ray absorptiometry (DXA), decreases significantly in the first few years after BS.…”

The Effectiveness of Nutritional Strategies in the Treatment and Management of Obesity: A Systematic Review

“…Other indirect disadvantages of weight loss may include complications of procedures adopted for weight loss, such as bariatric surgeries, for example, surgical and post-surgical complications, poor wound healing, and refeeding syndrome. However, due to the scarcity of data on the adverse effects of acute and chronic weight loss, further studies are needed to evaluate short and long-term complications related to acute or chronic weight loss [10,43,50,[71][72][73][87][88][89][90][91].…”