Hyperparathyroidism and vitamin D deficiency after laparoscopic gastric bypass

Am Surg. 2008 Jun;74(6):469-474; discussion 474-5.


Hyperparathyroidism (HPT) can occur after gastric bypass because of the alteration in vitamin D and calcium absorption. Adequate serum vitamin D concentrations have not been clearly defined in this patient population. Vitamin D (Vit D) and parathyroid hormone (PTH) were assessed 1 year after laparoscopic gastric bypass (LGB). The prevalence of HPT and Vit D deficiency were determined and their association was evaluated using Fisher's exact test. Ninety-three patients (aged 44 +/- 1.1 years, 49.6 +/- 0.67 Kg/m2 body mass index, 79.6% female, 69.6% white) were evaluated. The prevalence of Vit D deficiency (less than 20 ng/mL) and HPT (greater than 65 pg/mL) was 23.6 per cent (n = 22) and 25.7 per cent (n = 28), respectively. Among patients with HPT, only eight of 28 (28.6%) had Vit D deficiency, and of those with Vit D deficiency, only eight of 22 (36.4%) had HPT. There was a weak inverse correlation (r = -0.37) between PTH and Vit D. Blacks are at higher risk for Vit D deficiency. There was no significant association between Vit D deficiency and HPT, Vit D deficiency and Roux limb length, or HPT and Roux limb length. After LGB, Vit D deficiency and hyperparathyroidism occur commonly. Body mass index and Roux limb length are not associated with these two conditions, but racial differences do exist. There is a weak inverse correlation between Vit D and PTH. Further research is needed to elucidate the causes, treatments, and significance of HPT after LGB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Chi-Square Distribution
  • Female
  • Gastric Bypass / methods*
  • Humans
  • Hyperparathyroidism, Secondary / epidemiology
  • Hyperparathyroidism, Secondary / etiology*
  • Laparoscopy*
  • Male
  • Obesity, Morbid / surgery*
  • Parathyroid Hormone / blood
  • Postoperative Complications / epidemiology
  • Prevalence
  • Prospective Studies
  • Vitamin D / blood
  • Vitamin D Deficiency / epidemiology
  • Vitamin D Deficiency / etiology*


  • Parathyroid Hormone
  • Vitamin D