Relationships Between Vitamin D Status and PTH over 5 Years After Roux-en-Y Gastric Bypass: a Longitudinal Cohort Study.

PURPOSE: Secondary hyperparathyroidism (SHPT) after obesity surgery may affect bone health. Optimal vitamin D levels have not been established to prevent SHPT postoperatively. We investigated whether SHPT differed across threshold levels of serum 25-hydroxyvitamin D (S-25(OH)D) from 6 months up to 5 years after Roux-en-Y gastric bypass (RYGB). MATERIALS AND METHODS: We included 554 patients at follow-up 5 years postoperatively. Blood samples were analysed for S-25(OH)D, ionized calcium (iCa) and parathyroid hormone (PTH) during follow-up. RESULTS: PTH and prevalence of SHPT increased from 6 months to 5 years postoperatively, while S-25(OH)D and iCa decreased (all P < 0.001). PTH and SHPT development are related with S-25(OH)D, and PTH differed between all subgroups of S-25(OH)D. SHPT occurred less frequently across all subgroups of S-25(OH)D ≥ 50 nmol/l during follow-up: odds ratio (OR) 0.44 (95% CI 0.36-0.54) in patients with S-25(OH)D ≥ 50 nmol/l, OR 0.38 (0.30-0.49) with S-25(OH)D ≥ 75 nmol/l and OR 0.19 (0.12-0.31) with S-25(OH) D ≥ 100 nmol/l, all compared with S-25(OH)D < 50 nmol/l. At 5 years, 208/554 patients (38%) had SHPT; SHPT was found in 94/188 patients (50%) with S-25(OH)D < 50 nmol/l, in 69/222 (31%) with S-25(OH)D 50-74 nmol/l, in 40/117 (34%) with S-25(OH)D 75-99 nmol/l and in 5/27 (19%) with S-25(OH)D ≥ 100 nmol/l. An interaction existed between S-25(OH)D and iCa. Bone alkaline phosphatase remained increased with SHPT. CONCLUSIONS: A significant relationship existed between S-25(OH)D and development of PTH and SHPT. The prevalence of SHPT was lower with threshold levels 25(OH)D ≥ 50 nmol/l and ≥ 75 nmol/l over the 5 years, and lowest with S-25(OH)D ≥ 100 nmol/l.

Relationships of serum 25-hydroxyvitamin D, ionized calcium and parathyroid hormone after obesity surgery.

OBJECTIVE: The high prevalence of secondary hyperparathyroidism (SHPT) after obesity surgery is a concern for long-term bone health. Limited knowledge exists about optimal vitamin D and suppression of parathyroid hormone (PTH) after these procedures. The aim of this study was to investigate the prevalence of SHPT and its relation to vitamin D status. DESIGN: A cross-sectional study at Oslo University Hospital, Norway. PATIENTS: A total of 502 consecutive patients, age 22-64 years, attending 2-year follow-up after Roux-en-Y gastric bypass. MEASUREMENTS: A serum intact PTH >7.0 pmol/L in the absence of elevated serum ionized calcium (iCa) was considered as SHPT. Vitamin D status was defined by serum concentrations of 25-hydroxyvitamin D (S-25(OH)D). RESULTS: Altogether, 171 patients (34%) had SHPT. The prevalence of SHPT varied across the range of S-25(OH)D (P < 0.001), being highest (71%) with S-25(OH)D < 25 nmol/L. Compared with S-25(OH)D < 50 nmol/L, the prevalence of SHPT was lower with S-25(OH)D ≥ 50 nmol/L (29.0%; RR = 0.64 (95%-CI:0.50-0.81)) and S-25(OH)D ≥ 75 nmol/L (27.7%; RR = 0.61 (95%-CI:0.44-0.84)). S-25(OH)D ≥ 100 nmol/L was associated with the lowest PTH and the lowest prevalence of SHPT (16.0%; RR = 0.35 (95%-CI:0.14-0.88) compared with S-25(OH)D < 50 nmol/L) and the most normal calcium distribution. These associations were most pronounced with iCa in the lower range. A synergistic association was found for S-25(OH)D and iCa on SHPT. CONCLUSIONS: Vitamin D deficient patients had the highest prevalence of SHPT 2 years after gastric bypass. PTH and the prevalence of SHPT were notably lower with S-25(OH)D ≥ 100 nmol/L, compared with lower target levels.

Vitamin status after gastric bypass and lifestyle intervention: a comparative prospective study.

BACKGROUND: Bariatric surgery can lead to vitamin deficiencies. We aimed to assess the changes in blood vitamin concentrations in patients who were taking predefined supplements after gastric bypass surgery. METHODS: A total of 29 patients underwent gastric bypass and 24 unmatched controls underwent lifestyle intervention in a prospective, nonrandomized trial. The patients in the surgical group received multivitamin, iron, calcium, vitamin D, and vitamin B(12) supplements. No supplements were prescribed to the lifestyle group. The median body mass index decreased from 46 to 32 kg/m(2) after surgery and from 40 to 39 kg/m(2) after lifestyle intervention. RESULTS: Of the 53 included patients, 50 completed the 1-year follow-up examination (94%). Compared with the lifestyle patients, the surgical patients had increased vitamin B(6), folic acid, vitamin B(12), and lipid-adjusted vitamin E (P <.02 for each) concentrations but decreased vitamin A concentrations (P <.01) during follow-up. No significant difference between the 2 groups was found for vitamin B(1), vitamin C, or 25-hydroxyvitamin D. Most surgical patients reported taking their supplements. CONCLUSION: Gastric bypass patients adhering to a set of dietary supplements had mostly stable or increased vitamin concentrations compared with both their baseline values and the changes in a nonsurgical control group.

[Pregnancy shortly after bariatric surgery]. / Svangerskap like etter fedmeoperasjon.

Bariatric surgery is increasingly used to treat morbidly obese patients. Fertility in women may be enhanced after these procedures, owing to substantial weight loss and possibly a decreased absorption of oral contraceptives. We report a pregnancy that occurred two months after biliopancreatic diversion with duodenal switch in a 32-year-old woman. She subsequently developed haemolysis, elevated liver enzymes and low platelets count (HELLP) syndrome and had a weight loss of 43 kg (from the bariatric procedure) until the infant was delivered preterm by caesarean section (due to low activity). The infant was small in relation to the gestational age, with a weight of less than 50 % of the expected (780 g at 29.6 weeks). Histological examination demonstrated a small placenta with insufficient spiral artery trophoblast infiltration, possibly caused either by severe preeclampsia or by maternal nutritional deficiencies. Severe metabolic aberrations may complicate pregnancies after malabsorptive bariatric surgery. Patient preparations before weight-loss operations should include information on fertility and birth control in the postoperative period. Protocols for monitoring of patients that become pregnant after bariatric surgery are needed.

Wernicke encephalopathy after bariatric surgery: a systematic review.

OBJECTIVE: To review the clinical essentials of Wernicke encephalopathy (WE) after bariatric surgery. SUMMARY BACKGROUND DATA: An estimated 205,000 bariatric surgical procedures were performed in the United States in 2007. Such procedures may potentially lead to severe nutritional complications. METHODS: Literature searches were performed in Medline, Embase, and abstract collections. Inclusion criteria were WE after bariatric surgery, diagnosed by the presence of two or more of the following signs: mental status changes, eye movement abnormalities, cerebellar dysfunction, and dietary deficiency. RESULTS: Of 104 reported cases of WE after bariatric surgery, 84 cases were included. Gastric bypass or a restrictive procedure had been performed in 80 cases (95%). Admission to hospital for WE occurred within 6 months of surgery in 79 cases (94%). Frequent vomiting was a risk factor in 76 cases (90%) and had lasted for a median of 21 days at admission. Intravenous glucose administration without thiamine was a risk factor in 15 cases (18%). Brain magnetic resonance imaging identified lesions characteristic of WE in 14 of 30 cases (47%). Incomplete recovery was observed in 41 cases (49%); memory deficits and gait difficulties were frequent sequela. The recent increase in the use of bariatric surgery in the United States was associated with an increase in reported WE cases. CONCLUSIONS: The number of WE cases after bariatric surgery is substantially higher than previously reported. Surgeons, allied health providers, and patients need to be aware of the predisposing factors and symptoms to prevent and optimize the management of this condition.