Bone Mineral Density and Nutritional Profile in Morbidly Obese Women

Trabecular Bone Score and Bone Mineral Density in Postmenopausal Women with Morbid Obesity-A Clinical Paradox

Obesity has long been considered to have a protective effect on bone, but specific complications in those with morbid obesity are known to have a detrimental impact on bone architecture. We aimed to study the bone microarchitecture (TBS—trabecular bone score) and bone mineral density (BMD) in postmenopausal women with morbid obesity compared to obese and non-obese age-matched women. Eighty-five consecutive postmenopausal women with morbid obesity (body mass index (BMI) ≥ 35 kg/m²) were enrolled and compared to age-matched obese (n = 80) and non-obese postmenopausal controls (n = 85). The BMD and TBS were assessed in all subjects using a Hologic-QDR 4500-W Discovery-A DXA scanner. The mean BMD (gm/cm²) at the femoral neck in women with morbid obesity was found to be significantly lower as compared to the age-matched postmenopausal obese controls (0.723 versus 0.762, p-value = 0.002). The BMD at the lumbar spine and hip showed similar trends but were not statistically significant. The bone microarchitecture was found to be significantly lower in those with morbid obesity (1.205) as compared to the other two groups (obesity 1.244; non-obese 1.228) (p < 0.013). Though obesity was associated with a better bone density and bone microarchitecture in postmenopausal women, a paradoxical lower value was seen in those with morbid obesity.

Association of Visceral and Subcutaneous Fat Mass With Bone Density and Vertebral Fractures in Women With Severe Obesity

INTRODUCTION

The aim of this study was to evaluate the association of visceral and subcutaneous adipose tissue with bone mineral density (BMD), geometric indices of femoral neck strength and vertebral fractures in pre- and postmenopausal women with severe obesity.

METHODS

A cross-sectional study was conducted with pre- (n = 37) and postmenopausal (n = 21) women with body mass index higher than 40 kg/cm². BMD at total body, lumbar spine, hip and forearm, presence of vertebral fractures, lean mass, visceral, and subcutaneous adipose tissue were assessed by DXA. Geometric indices of femoral neck strength were calculated by DXA. Serum bone turnover markers (CTX and osteocalcin) and 25(OH)D were also measured.

RESULTS

BMD at all studied sites was similar in pre- and postmenopausal women. In postmenopausal women, total subcutaneous adipose tissue was inversely associated with BMD at total femur (β = -0.009; 95% confidence interval [CI] -0.017; -0.002) and with strength index (β = -0.03; 95% CI -0.04; -0.01). In premenopausal women, visceral adipose tissue was inversely associated with cross-sectional moment of inertia (β = -0.95; 95%CI -1.89; -0.01). Vertebral fractures were highly prevalent in premenopausal (32%), and even more frequent among postmenopausal women (55%).

CONCLUSION

Taken together, our results suggest that both visceral and subcutaneous fat may be detrimental for bone health in pre- and postmenopausal women, and that severe obesity may increase the risk of vertebral fractures, even in young women.

Evaluation of Dietary Assessment Tools Used in Bariatric Population

Severe obesity is associated with major health issues and bariatric surgery is still the only treatment to offer significant and durable weight loss. Assessment of dietary intakes is an important component of the bariatric surgery process. Objective: To document the dietary assessment tools that have been used with patients targeted for bariatric surgery and patients who had bariatric surgery and explore the extent to which these tools have been validated. Methods: A literature search was conducted to identify studies that used a dietary assessment tool with patients targeted for bariatric surgery or who had bariatric surgery. Results: 108 studies were included. Among all studies included, 27 used a dietary assessment tool that had been validated either as part of the study per se (n = 11) or in a previous study (n = 16). Every tool validated per se in the cited studies was validated among a bariatric population, while none of the tools validated in previous studies were validated in this population. Conclusion: Few studies in bariatric populations used a dietary assessment tool that had been validated in this population. Additional studies are needed to develop valid and robust dietary assessment tools to improve the quality of nutritional studies among bariatric patients.

Vitamin D alteration associated with obesity and bariatric surgery

Obesity and severe obesity constitute growing serious health problems reaching epidemic proportion in most countries. Interactions and relationships between obesity and bone tissue and its metabolism are complex but are more and more studied and recognized. Obesity is associated with an altered hormonal profile including particularly bone-regulating hormones like vitamin D. Bariatric surgery procedures, thanks to their effectiveness to achieve therapeutic endpoints for comorbidities associated with obesity, have had an increasing success. However, these surgeries by producing mechanical restriction and or malabsorption syndrome lead to nutritional deficiencies including vitamin D. In this review, we aim to (1) discuss the nutritional deficiency of vitamin D in the obese, (2) to summarize the different surgical options in bariatric surgery and to present the evidence concerning these procedures and their associated profile in vitamin D post-operative insufficiency, (3) to present the different recommendations in clinical practice to prevent or treat vitamin D deficiencies or insufficiencies in patients treated by bariatric surgery and finally to introduce emerging assumptions on the relationship between vitamin D, microbiota composition and circulating bile acids. Impact statement Obesity and severe obesity constitute growing serious health problems reaching epidemic proportion in most countries with a prevalence increasing from 6.4 in 1975 to 14.9% in 2014. This present review summarizes currently available data on vitamin D deficiencies in the obese population before and after bariatric surgery. The important evidence emerging from our evaluation confirms that obese patients are at risk of multiple nutritional deficiencies, especially vitamin D deficiency, before bariatric surgery. Our survey confirms that the precise role of the gut microbiome and its associated changes on the vitamin D metabolism after the different bariatric surgery procedures has not yet been studied. Furthermore, whether differences in the microbiota may alter the therapeutic responses to vitamin D is not known.

Changes in bone mineral density in women following 1-year gastric bypass surgery

BACKGROUND

Roux-en-Y gastric bypass (RYGB) surgery is the gold standard surgical treatment for obesity. However, unintended nutritional deficiencies following this surgery are common, including changes in bone metabolism. We assessed changes in bone mineral density (BMD), nutritional compounds, and bone resorption markers before and 1 year following RYGB surgery.

METHODS

Our study included 22 female patients with class II/III obesity. A clinical questionnaire, a 24-h recall, blood and urine samples, and dual-energy X-ray absorptiometry were provided.

RESULTS

Mean age was 37.2 ± 9.6 years; 86 % were Caucasian and 77.2 % were premenopausal. Mean preoperative body mass index was 44.4 ± 5.0 and 27.5 ± 4.5 kg/m(2) at 1-year follow-up (p < 0.001). 25-OH-vitamin D-levels were similar in both periods [11.7 (9.7-18.0) vs. 15.7 (10.2-2.7) pg/dL, p = 0.327]. Serum N-telopeptide (16.3 ± 3.4 vs. 38.2 ± 7.0 nM BCE, p < 0.001) and parathyroid hormone (45.4 ± 16.7 vs. 62.7 ± 28.9 pg/mL, p = 0.026) increased after RYGB surgery, reflecting bone resorption. BMD decreased after RYGB surgery in the lumbar spine (1.13 ± 0.11 vs. 1.04 ± 0.09 g/cm(2), p = 0.001), femoral neck (1.03 ± 0.15 vs. 0.94 ± 0.16 g/cm(2), p = 0.001), and total femur (1.07 ± 0.11 vs. 0.97 ± 0.15 g/cm(2), p = 0.003).

CONCLUSIONS

Decreased BMD in the lumbar spine, femoral neck, and total femur is detectable in women 1 year after RYGB surgery. Calcium malabsorption, caused by vitamin D deficiency and increased bone resorption, is partially responsible for these outcomes and should be targeted in future clinical trials.

Assessment of dietary habits, nutritional status and blood biochemical parameters in patients prepared for bariatric surgery: a preliminary study

Introduction

Morbid obesity needs to be treated by bariatric procedures. Proper dietary preparation of patients before surgery conditions their postoperative status.

Aim

Assessment of dietary habits, nutritional status and biochemical parameters of the blood in patients being prepared for different bariatric procedures.

Material and methods

The study involved a group of 27 obese adults: 19 women (mean age: 40.4 ±13.9 years) and 8 men (mean age: 39.6 ±12.7 years) qualified for bariatric procedures. Body composition, dietary habits and selected biochemical parameters of blood were assessed. Statistical analysis of the results was conducted using Statistica 9.0.

Results

Daily food rations consumed by women provided 1910.6 ±915.9 kcal/day, and by men 2631 ±1463.2 kcal/day on average. In both groups, the consumption of major nutrients was found to be inadequate. In both groups, deficiency was observed in the dietary intake of folic acid and potassium. Additionally, there was a decrease in the intake of vitamin D₃, calcium and iron in women and magnesium in men. In the two groups, disturbances were noted in lipid and carbohydrate metabolism.

Conclusions

Our study indicates the necessity for dietary instructions in bariatric patients with regard to proper dietary habits and to reduce the risk of malnutrition before and after surgery.

Extraskeletal effects of vitamin D: facts, uncertainties, and controversies

Vitamin D was long viewed as a hormone acting chiefly to regulate calcium-phosphate metabolism and bone mineralization. Over the last decade, however, basic science and clinical researchers have produced a bewildering amount of information on the extraskeletal effects of vitamin D. This article is a review of the clinical and biological actions of vitamin D including effects on the immune system, auto-immune diseases, infections, cancer, metabolic syndrome, fall risk, cognitive function, and muscle function.