Phosphocalcic Metabolism after Biliopancreatic Diversion

Biliopancreatic diversion requires multiple vitamin and micronutrient adjustments within 2 years of surgery

BACKGROUND

Malabsorptive bariatric procedures require multiple vitamin supplements, especially regarding fat-soluble vitamins. The exact amount required to maintain normal serum concentrations is still largely unknown. Based on the initial postoperative prescription, we assessed the number of adjustments and the amount of vitamins/micronutrients to normalize the biological markers 2 years after the biliopancreatic diversion with duodenal switch (BPD/DS).

METHODS

A total of 112 consecutive patients had a laparoscopic BPD/DS between February 2007 and November 2010 for a body mass index of 53.1±5.9 kg/m² at a private hospital. Complete blood checks with vitamin status were obtained at each of the 3-month interval visits during the 1(st) postoperative year as well as twice during the 2(nd) year.

RESULTS

Initially, all of the patients were prescribed daily 25,000 International units (IU) of vitamin A, 1000 mg of calcium, multivitamins, and 1900 IU of vitamin D3. Significant adjustments were necessary 3.6±1.1 times during this period. A total of 80% of the patients required added vitamin A, vitamin D, as well as calcium, zinc, and iron. After 2 years,≥20% of patients exhibited vitamin A and iron deficiency with low prealbumin or micropenic anemia. Seventy percent had vitamin D deficiency and 50% secondary hyperparathyroidism.

CONCLUSION

The initial prescription was insufficient to cover the requirements after BPD/DS. At least 3000 mg of calcium with 7000 IU of vitamin D, 50,000 IU of vitamin A, 40 mg of zinc, and 200 mg of iron must be prescribed to start with. The trend toward a decrease in 25 OH vitamin D and hyperparathyroidism remains difficult to control although it can result from increased bone turnover during the early postoperative period.

Vitamin D status and supplementation in morbid obesity before and after bariatric surgery

Interest in vitamin D has increased recently because of its role on multiple biologic mechanisms and the high prevalence of deficits, particularly in obese individuals. The epidemic of morbid obesity has led to a growing number of bariatric surgical procedures, the only therapeutic modality with a reasonable chance of success on a long-term basis. Vitamin D status following bariatric surgery depends on several interacting factors and should be monitored carefully. We review vitamin D, calcium and parathyroid hormone dynamics following the main types of bariatric surgery and the guidelines for the postoperative periodic assessment and therapy.

Effect of a single 'megadose' intramuscular vitamin D (600,000 IU) injection on vitamin D concentrations and bone mineral density following biliopancreatic diversion surgery

BACKGROUND

Vitamin D (VitD) deficiency is common following biliopancreatic diversion (BPD). We conducted a prospective open-label study to evaluate the efficacy of a single intramuscular injection with 600,000 IU of cholecalciferol in an arachis oil depot formulation (VitD3, Arachitol Solvay Pharmacia) as an adjunct to regular oral VitD supplementation (Citrical+D) for a period of 12 months following BPD surgery.

METHODS

Some 29 patients who had undergone BPD during 2000-2005 were recruited and received a single injection of 600,000 IU of cholecalciferol. Venous blood VitD, parathyroid hormone (PTH), alkaline phosphatase (ALP), ionised calcium and urinary N-telopeptide (NTX) were assessed at baseline and at 1.5, 3, 6, 9 and 12 months post-injection. Bone mineral density (BMD) was determined at baseline and 12 months post-injection.

RESULTS

VitD concentrations (mean +/- SD) were significantly increased from baseline values (61.5 +/- 18.8 nmol/L) at 1.5 months (92.4 +/- 21.5, p < 0.001), 3 months (100.5 +/- 24.4, p < 0.001) and 6 months (79.1 +/- 20.9, p = 0.014) post-injection, with non-significant elevations at 9 months (73.3 +/- 15.1, p = 0.248) and 12 months (73.4 +/- 17.3, p = 0.278). The proportion of patients with 'normalised' VitD levels was significantly higher at all post-injection time points (range, 93-100%) compared with baseline (71.4%; p < 0.01). Ionised calcium and ALP remained within normal levels at baseline and all follow-up time points, although ionised calcium decreased by 3.4% (p = 0.015) and ALP increased by 14.6% (p = 0.021) at 12 months compared with baseline. No significant change in PTH, NTX or BMD was observed.

CONCLUSIONS

Intramuscular cholecalciferol injection, as an adjunct to oral supplementation, appears a safe and effective method to increase and maintain VitD levels after BPD.

Mineral metabolism in obese patients following vertical banded gastroplasty

BACKGROUND

Bone disease has been described in patients after surgical treatment for obesity, but few studies have dealt with the impact of vertical banded gastroplasty on mineral metabolism. We have examined bone mineral metabolism in morbidly obese patients before and after 3 months after vertical banded gastroplasty without vitamin D supplementation.

METHODS

Sixteen morbidly obese patients (14 women, 2 men) with a mean (+/-SD) age of 38 +/- 9 years and a body mass index (BMI) of 47.1 +/- 8.1 kg/m2 were studied. No vitamin D supplementation was given. Body weight, fat mass, calcium, 25OHD, iPTH, bone remodeling markers, and leptin levels were measured at baseline and after weight loss.

RESULTS

Mean weight loss was 28 +/- 11 kg; BMI and body fat mass decreased by 20 and 35%, respectively. Bone resorption markers and albumin-corrected serum calcium increased after operation, whereas iPTH fell. Serum 25OHD levels rose. Leptin levels decreased. Serum iPTH was positively correlated with weight, BMI, and fat mass before operation (p < 0.05), and its decline after weight reduction was negatively associated with the increase in bone resorption markers (p < 0.01). Leptin concentration was correlated with BMI and body fat mass (p < 0.05) both before and after surgery.

CONCLUSIONS

Weight reduction obtained in morbidly obese subjects 3 months after vertical banded gastroplasty increases bone turnover markers and decreases PTH secretion. Serum 25OHD levels rose. Therefore, no reasons for a metabolic bone disease related to hypovitaminosis D were readily apparent. However, an increase in bone turnover, which is generally regarded as a potential risk factor for osteoporosis, was observed. Further work is needed to clarify the importance of this turnover increase in the long run.