Obesity, Bariatric Surgery, and Vitamin D

The high prevalence of obesity is a worldwide problem associated with multiple comorbidities, including cardiovascular diseases. Vitamin D deficiency with secondary hyperparathyroidism is common in obese individuals and can be aggravated after bariatric surgery. Moreover, there is no consensus on the optimal supplementation dose of vitamin D in postbariatric surgical patients. We present new data on the variability of 25(OH)D response to supplementation in postmenopausal obese women. It is important to recognize and treat vitamin D deficiency before bariatric surgery to avoid postoperative complications, such as metabolic bone disease with associated high fracture risk. The objective of this article is to discuss the bone metabolism consequences of vitamin D deficiency after bariatric surgery.

The Clinical Utility of Vertebral Fracture Assessment in Predicting Fractures

Vertebral fracture (VF) is the most common type of osteoporotic fracture. VFs are associated with diminished quality of life and high morbidity and mortality. The presence of a VF, especially a recent one, is an important risk factor for developing another fracture. However, most VFs are not clinically recognized. VF assessment by dual-energy X-ray absorptiometry is a convenient, low-cost, low-radiation, reliable method to identify VFs during bone mineral density measurement. The finding of a previously unrecognized VF may change the diagnostic classification, assessment of fracture risk, and treatment strategies. This paper focuses on the utility of VF assessment in clinical practice.

A randomized, parallel group, double-blind, multicentre study comparing the efficacy and safety of Avandamet (rosiglitazone/metformin) and metformin on long-term glycaemic control and bone mineral density after 80 weeks of treatment in drug-naïve type 2 diabetes mellitus patients

AIM

The purpose of this study was to evaluate if superior glycaemic control could be achieved with Avandamet® (rosiglitazone/metformin/AVM) compared with metformin (MET) monotherapy, and if glycaemic effects attained with AVM are durable over 18 months of treatment. Bone mineral density (BMD) and bone biomarkers were evaluated in a subgroup of patients.

METHODS

This was a phase IV, randomized, double-blind, multi-centre study in 688, drug naÏve, male and female patients who had an established clinical diagnosis of type 2 diabetes mellitus (T2DM). Patients were randomized in a 1 : 1 ratio either to AVM or MET.

RESULTS

As initial therapy in patients with T2DM, AVM was superior to MET in achieving statistically significant reductions in glycated haemoglobin (HbA1c) (p < 0.0001) and fasting plasma glucose (FPG) (p < 0.001), with more patients reaching recommended HbA1c and FPG targets for intensive glycaemic control. The glycaemic effects attained with AVM compared to MET monotherapy were durable over 18 months of treatment. In the bone substudy, AVM was associated with a significantly lower BMD in comparison with MET at week 80 in the lumbar spine and total hip (p < 0.0012 and p = 0.0005, respectively). Between-treatment differences were not statistically significant for distal one-third of radius BMD, femoral neck BMD or total BMD.

CONCLUSION

Superior glycaemic control was achieved with AVM compared with MET monotherapy. The superior glycaemic effects were shown to be durable over 18 months of treatment. AVM was associated with a significantly reduced BMD in comparison with MET at week 80 in the lumbar spine and total hip.