Preoperative Nutritional Status of Patients Undergoing Roux-en-Y Gastric Bypass for Morbid Obesity

The link between obesity and low circulating 25-hydroxyvitamin D concentrations: considerations and implications

“…The observation that obesity is associated with below-normal serum 25-hydroxyvitamin D concentrations and/or overt deficiency is not new; however, as obesity prevalence has grown, so have the number of reports in the literature regarding this phenomenon. [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] Some of the most recent information about low vitamin D status and obesity comes from studies in bariatric surgery patients, reporting low preoperative circulating levels of 25-hydroxyvitamin D. [21][22][23][24][25][26][27][33][34][35][36][37][38] In fact, a recent systematic review of 14 studies with about 1500 patients undergoing bariatric surgical procedures confirmed that obese individuals have serum 25-hydroxyvitamin D levels below 80 nmol l À1 preoperatively. 39 Other investigators have reported that body mass index (BMI) 25,26,[40][41][42][43][44][45][46] and body fat 20,45,…”

Nutritional Implications of Obesity: Before and After Bariatric Surgery

“…Flancbaum et al in their retrospective analysis of 379 patients undergoing Roux-en-Y gastric bypass were able to identify vitamin D deficiency in 68%, iron deficiency in 44%, and thiamin deficiency in 29% of their patients. 30 Contrasting evidence on the relationship between 25OHD, PTH, and BMI exist. In fact, although some authors were able to demonstrate that the hyperparathyroidism found in morbidly obese individuals is mostly secondary to vitamin D deficiency, others have suggested that excess PTH production can determine weight gain by promoting lipogenesis.…”

“…40 Preoperative deficiencies of this vitamin have been reported to be as high as 29% in certain series, and it is higher in African American and Hispanic patients. 30 The alteration of micronutrients in obese patients, such as vitamin A, can have end-organ consequences. This is the case for nonalcoholic steatohepatitis (NASH), which can progress from steatosis to steatohepatitis, fibrosis, and cirrhosis.…”

Deficiências de micronutrientes no pré-operatório de cirurgia bariátrica

“…In this context, Flancbaum et al 9 retrospectively analyzed the preoperative serum calcium, albumin, 25-OH vitamin D, iron, ferritin, hemoglobin, vitamin B12 and thiamine values of 379 consecutive patients (320 women and 59 men, with mean body mass index of 51.8 ± 10.6 kg/ m 2 ). Deficiencies in iron (43.9%), ferritin (8.4%), hemoglobin (22% in women and 19.1% men), thiamine (29%), and 25-OH vitamin D (68.1 %) were observed.…”