Karen Basfi-Fer

University of Santiago, Chile, Santiago, Region Metropolitana de Santiago, Chile

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Publications (8)30.06 Total impact

  • Source
    Article: Heme- and nonheme-iron absorption and iron status 12 mo after sleeve gastrectomy and Roux-en-Y gastric bypass in morbidly obese women.
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    ABSTRACT: The effect of bariatric surgery on iron absorption is only partially known. The objective was to study the effects of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGBP) on heme- and nonheme-iron absorption and iron status. Fifty-eight menstruating women were enrolled in this prospective study [mean (±SD) age: 35.9 ± 9.1 y; weight: 101.7 ± 13.5 kg; BMI (in kg/m(2)): 39.9 ± 4.4]. Anthropometric, body-composition, dietary, and hematologic indexes and heme- and nonheme-iron absorption-using a standardized meal containing 3 mg Fe-were determined before and 12 mo after surgery. Forty-three subjects completed the 12-mo follow-up. Iron supplements were strictly controlled. Heme-iron absorption was 23.9% before and 6.2% 12 mo after surgery (P < 0.0001). Nonheme-iron absorption decreased from 11.1% to 4.7% (P < 0.0001). No differences were observed by type of surgery. Iron intakes from all sources of supplements were 27.9 ± 6.2 mg/d in the SG group and 63.2 ± 21.1 mg/d in the RYGBP group (P < 0.001). Serum ferritin and total-body iron decreased more after RYGBP than after SG. Iron (heme and nonheme) absorption is markedly reduced after SG and RYGBP. The magnitude of the decrease in heme-iron absorption is greater than that of nonheme iron. The amounts suggested as iron supplements may need to be increased to effectively prevent iron-status impairment. This trial was registered at controlled-trials.com as ISRCTN31937503.
    American Journal of Clinical Nutrition 09/2012; 96(4):810-7. · 6.67 Impact Factor
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    Article: Changes in ghrelin concentrations one year after resective and non-resective gastric bypass: associations with weight loss and energy and macronutrient intakes.
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    ABSTRACT: Ghrelin is a potent stimulator of appetite and synthesized in the stomach. Its role in weight loss after gastric bypass (GBP) is still controversial. The aim of this study was to evaluate the relation between weight loss and food intake and between weight loss and changes in serum ghrelin concentrations 1 y after GBP with resection of the bypassed stomach (R-GBP) and without resection (NR-GBP). Of 50 women (37.6 ± 10.2 y old, body mass index 43.8 ± 4.8 kg/m²) with GBP, 26 had R-GBP and 24 had NR-GBP. Body weight, body composition (dual energy x-ray absorptiometry), food intake, and serum ghrelin at baseline and 12 mo after GBP were measured. The percentage of excess weight loss was 68.9 ± 12.8% at 12 mo after GBP. At 12 mo, the decrease of serum ghrelin was greater in the R-GBP group (-25.3 ± 22.5%) compared with the NR-GBP group (+11.2 ± 50.9%, P < 0.005). After adjustment by the baseline excess of body weight, there was a greater percentage of excess weight loss in the R-GBP group only at 6 mo (61.8% versus 54.9%, P = 0.011). After controlling for the baseline intake, a significant lower carbohydrate intake was observed in the R-GBP group 6 mo after surgery (P < 0.05). A greater decrease in ghrelin levels was observed only in patients who underwent R-GBP at 12 mo after surgery. This difference was not associated with differences in dietary intakes or weight loss at the same time point. Therefore, the small gastric pouch is probably more important than decreased ghrelin levels in producing long-term weight loss after R-GBP.
    Nutrition 02/2012; 28(7-8):757-61. · 3.03 Impact Factor
  • Article: Zinc absorption and zinc status are reduced after Roux-en-Y gastric bypass: a randomized study using 2 supplements.
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    ABSTRACT: Micronutrient deficiencies are common in patients undergoing gastric bypass. The effect of this type of surgery on zinc absorption and zinc status is not well known. The objective was to evaluate the effects of Roux-en-Y gastric bypass (RYGBP) on zinc status and zinc absorption at different stages after surgery. We hypothesized that zinc status would be significantly impaired after surgery and that this impairment would be less severe in subjects receiving increased supplemental zinc. We also hypothesized that zinc absorption would be lower after surgery. Anthropometric and body-composition variables and dietary and biochemical indexes of zinc status and zinc absorption were determined in 67 severe and morbidly obese women [mean (±SD) age: 36.9 ± 9.8 y; BMI (in kg/m(2)): 45.2 ± 4.7] who underwent RYGBP. The subjects were randomly assigned to 1 of 2 vitamin-mineral supplementation groups. Measurements were made before and 6, 12, and 18 mo after surgery. Fifty-six subjects completed the 18-mo follow-up. Mean plasma zinc, erythrocyte membrane alkaline phosphatase activity, and the size of the rapidly exchangeable zinc pool decreased after RYGBP. Percentage zinc absorption decreased significantly from 32.3% to 13.6% at 6 mo after RYGBP and to 21% at 18 mo after surgery. No effect of supplement type was observed. Zinc status is impaired after RYGBP, despite the finding that dietary plus supplemental zinc doubled recommended zinc intakes in healthy persons. Zinc absorption capacity is significantly reduced soon after RYGBP, with no major changes until 18 mo after surgery.
    American Journal of Clinical Nutrition 08/2011; 94(4):1004-11. · 6.67 Impact Factor
  • Article: [Quality of the diet of women with severe and morbid obesity undergoing gastric bypass and sleeve gastrectomy].
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    ABSTRACT: The objective of this study was to evaluate the changes of dietary intake and quality of the diet in patients undergoing gastric bypass and sleeve surgery. In 36 women with severe and morbid obesity it was assessed their nutrient intakes and dietary quality before and 6 months after bariatric surgery through three-day food records. Vitamin and mineral intakes from supplements were strictly controlled. Energy and nutrient intakes were significantly decreased 6 months after surgery bypass compared to the pre-surgery period with the exceptions of calcium and vitamin C. No differences were observed between groups. The Dietary quality index was also similar in both groups. Dietary intakes of calcium, iron, zinc, copper, folic acid, vitamin C, and vitamin E were below 100% of adequacy from at the 6th month after the surgery. Nevertheless, by considering both diet and supplements supply, nutrient adequacy of all but calcium and folic acid was above 100% in both groups. Gastric bypass patients presented greater values. In conclusion, these patients present an important reduction of their energy and nutrient intakes, with no major impact of the type of surgery. Supplement characteristics are crucial to cover nutritional needs.
    Archivos latinoamericanos de nutrición 03/2011; 61(1):28-35. · 0.23 Impact Factor
  • Article: Trace element status and inflammation parameters after 6 months of Roux-en-Y gastric bypass.
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    ABSTRACT: Knowledge about the practical consequences of the nutritional status of Fe, Zn, and Cu and inflammation in obesity is limited. The objective of this study was to evaluate changes on trace element status and their potential associations with selected inflammation parameters in patients after Roux-en-Y gastric bypass (RYGBP). Sixty-three women (mean age, 36.9 ± 9.2 years, body mass index, 43.8 ± 4.3 kg/m²) were evaluated at baseline and 6 months after RYGBP. Anthropometric (weight, waist circumference), body composition (fat mass and fat-free mass), dietary (nutrient intakes), and metabolic and inflammation (glucose, insulin, HOMA-IR, adiponectin, HDL-cholesterol, LDL-cholesterol, triglycerides, hs-CRP, leukocytes, polymorphonuclear neutrophils (PMN)) parameters were determined in addition to selected indices of Fe, Zn, and Cu status. All but one (HDL-cholesterol) metabolic and inflammation parameters had significant differences when compared before and after RYGBP. Hemoglobin, serum ferritin, the size of the rapidly exchangeable zinc pool, and plasma copper decreased after RYGBP. Plasma and hair zinc, as well as zinc protoporphyrin increased. The change in Hb was significantly associated (p < 0.05) to the change in leukocytes (r = 0.33) and adiponectin (r = -0.44). Zinc protoporphyrin change was associated to the change in PMN (r = 0.32) and HDL-cholesterol (r = -0.29). No other associations between the changes of the rest of Fe, Zn, and Cu parameters with the changes of any of the metabolic and inflammation parameters were observed. RYGBP produced significant weight and fat mass losses, with improvement of metabolic and inflammation parameters. Iron, zinc, and copper status were impaired after the surgery.
    Obesity Surgery 02/2011; 21(5):561-8. · 3.29 Impact Factor
  • Article: Iron absorption and iron status are reduced after Roux-en-Y gastric bypass.
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    ABSTRACT: Iron deficiency and iron deficiency anemia are common in patients who undergo gastric bypass. The magnitude of change in iron absorption is not well known. The objective was to evaluate the effects of Roux-en-Y gastric bypass (RYGBP) on iron status and iron absorption at different stages after surgery. We hypothesized that iron absorption would be markedly impaired immediately after surgery and would not improve after such a procedure. Anthropometric, body-composition, dietary, hematologic, and iron-absorption measures were determined in 67 severe and morbidly obese women [mean age: 36.9 +/- 9.8 y; weight: 115.1 +/- 15.6 kg, body mass index (BMI: in kg/m(2)); 45.2 +/- 4.7] who underwent RYGBP. The Roux-en-Y loop length was 125-150 cm. Determinations were carried out before and 6, 12, and 18 mo after surgery. Fifty-one individuals completed all 4 evaluations. The hemoglobin concentration decreased significantly throughout the study (repeated-measures analysis of variance). The percentage of anemic subjects changed from 1.5% at the beginning of the study to 38.8% at 18 mo. The proportion of patients with low serum ferritin increased from 7.5% to 37.3%. The prevalence of iron deficiency anemia was 23.9% at the end of the experimental period. Iron absorption from both a standard diet and from a standard dose of ferrous ascorbate decreased significantly after 6 mo of RYGBP to 32.7% and 40.3% of their initial values, respectively. No further significant modifications were noted. Iron absorption is markedly reduced after RYGBP with no further modifications, at least until 18 mo after surgery.
    American Journal of Clinical Nutrition 08/2009; 90(3):527-32. · 6.67 Impact Factor
  • Article: [Evolution and quality of the diet of women with severe and morbid obesity undergoing gastric bypass].
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    ABSTRACT: Evolution and quality of the diet of women with severe and morbid obesity undergoing gastric bypass. The objective of this study was to evaluate the changes of dietary intake and quality of the diet in patients undergoing gastric bypass. In forty-four women with severe and morbid obesity it was assessed their nutrient intakes before and 6, 12, and 18 months after gastric bypass by using three-day food records. Vitamin and mineral intakes from supplements were strictly controlled though personalized records. With the exceptions of calcium and vitamin A, energy and nutrient intakes were significantly decreased at 6, 12, and 18 month after bypass compared to the pre-surgery period. Dietary intakes of calcium, iron, zinc, copper, folic acid, vitamin C, and vitamin E were below 100% of adequacy from the 6th month after the surgery and thereafter. This situation is reverted when nutrient intakes supplied by supplements are taken into account. Although a "U" shape trend was observed in the nutrient intakes results during the experimental period, in most cases the differences between the observed values at month 12 and 18 were not significant. In conclusion, these patients had important reductions of their energy and nutrient intakes as result of gastric bypass. Routine supplements may correct this situation, nevertheless, the anatomical alterations inherent to this type of surgery may cause that total nutrient intakes reaching adequacy values slightly above 100%, may not necessarily be able to avoid the development of nutritional deficiencies.
    Archivos latinoamericanos de nutrición 04/2009; 59(1):7-13. · 0.23 Impact Factor
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    Article: Changes in bone mineral density, body composition and adiponectin levels in morbidly obese patients after bariatric surgery.
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    ABSTRACT: Gastric bypass surgery (GBP) is increasingly used as a treatment option in morbid obesity. Little is known about the effects of this surgery on bone mineral density (BMD) and the underlying mechanisms. To evaluate changes on BMD after GBP and its relation with changes in body composition and serum adiponectin, a longitudinal study in morbid obese subjects was conducted. Forty-two women (BMI 45.0 +/- 4.3 kg/m(2); 37.7 +/- 9.6 years) were studied before surgery and 6 and 12 months after GBP. Percentage of body fat (%BF), fat-free mass (FFM), and BMD were measured by dual-energy X-ray absorptiometry and serum adiponectin levels by RIA. Twelve months after, GBP weight was decreased by 34.4 +/- 6.5% and excess weight loss was 68.2 +/- 12.8%. Significant reduction (p < 0.001) in total BMD (-3.0 +/- 2.1%), spine BMD (-7.4 +/- 6.8%) and hip BMD (-10.5 +/- 5.6%) were observed. Adiponectin concentration increased from 11.4 +/- 0.7 mg/L before surgery to 15.7 +/- 0.7 and 19.8 +/- 1.0 at the sixth and twelfth month after GBP, respectively (p < 0.001). Thirty-seven percent of the variation in total BMD could be explained by baseline weight, initial BMD, BF reduction, and adiponectin at the twelfth month (r (2) = 0.373; p < 0.001). Adiponectin at the twelfth month had a significant and positive correlation with the reduction of BMD, unrelated to baseline and variation in body composition parameters (adjusted correlation coefficient: r = 0.36). GBP induces a significant BMD loss related with changes in body composition, although some metabolic mediators, such as adiponectin increase, may have an independent action on BMD which deserves further study.
    Obesity Surgery 08/2008; 19(1):41-6. · 3.29 Impact Factor