Long-term hypovitaminosis D and secondary hyperparathyroidism outcomes of the Roux-en-Y gastric bypass: a systematic review

Obes Rev. 2017 May;18(5):560-566. doi: 10.1111/obr.12525. Epub 2017 Mar 8.


Introduction: Pre-operative Vitamin D deficiency is markedly prevalent in prospective bariatric surgery patients. While bariatric surgery leads to significant weight loss, it can exacerbate or prolong Vitamin D deficiency. We systematically reviewed the literature to assess whether secondary hyperparathyroidism is maintained in the medium to long term in patients following the Roux-en-Y gastric bypass.

Methods: A comprehensive literature search was conducted through Medline, Embase, Scopus, Web of Science, Dare, Cochrane library and HTA database. The search terms used were bariatric surgery, gastric bypass and hyperparathyroidism.

Results: Fourteen studies were included (n = 2688 subjects). Parathyroid hormone levels rose gradually from a mean pre-operative level of 5.69 ± 1.2 pmol/L to 6.36 ± 0.77 pmol/L, 7.59 ± 0.73 pmol/L and 8.29 ± 1.41 pmol/L at 2 years, between 2 and 5 years, and beyond 5 years, respectively. Vitamin D levels slowly fell to a mean of 20.50 ± 4.37 ng/mL and 20.76 ± 3.80 ng/mL between follow-up intervals 2-5 years and beyond 5, respectively.

Conclusion: It appears that hyperparathyroidism persists at 5-year follow-up after gastric bypass, despite most patients being supplemented with calcium and Vitamin D.

Keywords: Gastric bypass; hyperparathyroidism; hypovitaminosis D; long-term outcomes.

Publication types

  • Review
  • Systematic Review

MeSH terms

  • Gastric Bypass / adverse effects*
  • Humans
  • Hyperparathyroidism, Secondary / blood*
  • Hyperparathyroidism, Secondary / epidemiology
  • Non-Randomized Controlled Trials as Topic
  • Randomized Controlled Trials as Topic
  • Time Factors
  • Vitamin D Deficiency / blood*
  • Vitamin D Deficiency / epidemiology