Elsevier

Nutrition

Volume 25, Issues 11–12, November–December 2009, Pages 1150-1156
Nutrition

Applied nutritional investigation
Prevalence of nutrient deficiencies in bariatric patients

https://doi.org/10.1016/j.nut.2009.03.012Get rights and content

Abstract

Objective

The aims of this study were to determine the prevalence of nutrient deficiencies in patients who present for bariatric surgery, assess nutritional status after surgery, and compare these with preoperative levels.

Methods

A retrospective study was conducted to identify preoperative and 1-year postoperative nutrition deficiencies in patients undergoing bariatric surgery. The screening included serum ferritin, vitamin D, vitamin B12, homocysteine, folate, red blood cell folate, and hemoglobin. Results were available for 232 patients preoperatively and 149 patients postoperatively. Two-tailed χ2 tests and paired-sample t tests were used.

Results

Preoperatively, vitamin D deficiency was noted at 57%. The prevalence of abnormalities 1 year after roux-en-Y gastric bypass was higher compared with preoperative levels (P < .05). After surgery, anemia was detected in 17%, elevated homocysteine levels (women only) in 29%, low ferritin in 15%, low vitamin B12 in 11%, and low RBC folate in 12%. Mean hemoglobin, ferritin, and RBC folate levels deteriorated significantly but remained well within normal ranges. The prevalence of vitamin D deficiencies decreased, but not significantly. In sleeve gastrectomy patients, mean ferritin levels decreased (P < .05), without any patient developing a deficiency.

Conclusion

Vitamin D deficiency is common among morbidly obese patients seeking bariatric surgery. Because the prevalence of micronutrient deficiencies persists or worsens postoperatively, routine nutrition screening, recommendation of appropriate supplements, and monitoring adherence are imperative in this population.

Introduction

Bariatric surgery has been recognized to be the most effective long-term treatment for the morbidly obese (body mass index [BMI]  40 kg/m2), with demonstrated significant and durable weight loss, resolution or improvement of comorbidities [1], [2], and subsequent reduction in mortality [3], [4].

Bariatric procedures produce changes in the gastrointestinal anatomy and physiology. As a consequence, there is a change in the quantity and quality of diet, which may result in vitamin and mineral deficiencies [5]. Studies examining preoperative and postoperative nutritional status are few, and the reported prevalence of these deficiencies varies widely because of varying definitions of deficiency, patient populations, surgical techniques, supplement protocols, and lengths and completion of patient follow-up [5]. Furthermore, studies have shown that calcium, vitamin D, and iron deficiencies, as well as hyperparathyroidism, are prevalent among the morbidly obese before bariatric surgery [6]. Given the paucity of data exploring nutritional status among bariatric populations and the likely elevated risk for nutritional deficiencies, nutrition screening and treatment protocols appear important. These protocols will need to vary depending on the chosen bariatric procedure.

The 3 types of bariatric surgery done at our hospital are adjustable gastric banding (AGB), Roux-en-Y gastric bypass (RYGB), and sleeve gastrectomy (SG). Nutrition screening is carried out routinely before surgery, as well as 6 months, 9 months, and 1 year after surgery. The aims of this study were to determine the prevalence of nutrient deficiencies in patients who present for bariatric surgery and to assess nutritional parameters 1 year after surgery and compare these with preoperative levels.

Section snippets

Materials and methods

A retrospective study was carried out on 244 consecutive patients who had undergone laparoscopic bariatric surgery by a single surgeon (J.J.) at St. George Hospital (Sydney, Australia) between February 2005 and June 2007. There were 55 AGB, 124 RYGB, and 65 SG surgeries. All patients are seen by a dietitian for routine nutrition assessment and counseling before and after surgery. The postoperative protocol involved instructing all patients to take a liquid, effervescent, or chewable

Results

Subjects' characteristics are shown in Table 1. The majority of patients (64%) were women, mostly aged 30 to 60 years (mean age, 46 ± 11 years). Nearly all patients had BMIs  35 kg/m2. In 10 patients (6 of whom underwent RYGB), BMIs were between 30 and 34.9 kg/m2, and the indication for surgery was the treatment of insulin resistance or diabetes mellitus. Percentage excess weight loss was not one of the key outcome measures in this study, so it is reported only for patients who had biochemical

Preoperative abnormalities

In patients presenting for bariatric surgery, vitamin D deficiency was the only consistent deficiency identified. More than half the patients had vitamin D deficiencies. Our findings are consistent with those of other studies, which reported vitamin D deficiencies in 60% [7] to 80% [8] of patients preoperatively. Furthermore, a quarter of the patients experienced elevated iPTH levels. Hyperparathyroidism has been observed in 25% [9] to 48% [7] in the morbidly obese.

Although an association

Conclusion

Vitamin D deficiency is common among morbidly obese patients seeking bariatric surgery. Because the prevalence of micronutrient deficiencies persists or worsens postoperatively, to ensure optimal nutrition status, routine nutrition screening, the recommendation of appropriate supplements, and monitoring adherence is imperative in this population.

Acknowledgments

We would like to thank the staff of St. George Bariatric Unit and Kelly Lambert and Karen Walton of the University of Wollongong for their invaluable support and guidance.

References (42)

  • M.A. Maggard et al.

    Meta-analysis: surgical treatment of obesity

    Ann Intern Med

    (2005)
  • L. Sjostrom et al.

    Effects of bariatric surgery on mortality in Swedish obese subjects

    N Engl J Med

    (2007)
  • N.V. Christou et al.

    Surgery decreases long-term mortality, morbidity, and health care use in morbidly obese patients

    Ann Surg

    (2004)
  • R.F. Kushner

    Micronutrient deficiencies and bariatric surgery

    Curr Opin Endocrinol Diabetes

    (2006)
  • R.D. Bloomberg et al.

    Nutritional deficiencies following bariatric surgery: what have we learned?

    Obesity Surg

    (2005)
  • J. Ybarra et al.

    Unchanged hypovitaminosis D and secondary hyperparathyroidism in morbid obesity after bariatric surgery

    Obesity Surg

    (2005)
  • N. Hamoui et al.

    Calcium metabolism in the morbidly obese

    Obesity Surg

    (2004)
  • S.J. Parikh et al.

    The relationship between obesity and serum 1,25-dihydroxy vitamin D concentrations in healthy adults

    J Clin Endocrinol Metab

    (2004)
  • N.H. Bell et al.

    Evidence for alteration of the vitamin D-endocrine system in obese subjects

    J Clin Invest

    (1985)
  • E.M. Ross

    Evaluation and treatment of iron deficiency in adults

    Nutr Clin Care

    (2002)
  • A.K. Madan et al.

    Vitamin and trace mineral levels after laparoscopic gastric bypass

    Obesity Surg

    (2006)
  • Cited by (249)

    • Nutrition in Surgery: An Orthopaedic Perspective

      2023, Journal of Bone and Joint Surgery
    View all citing articles on Scopus
    View full text