Calcium - I found the perfect one for me.

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DOI: 10.1089

301

underexposure to solar ultraviolet radiation, and

malabsorption. However, the prevalent cause of

pre-op vitamin D deficiency among WLS patients

is thought to bedecreased availability of vitaminD

due to increased fat mass.

Given the higher risk for calcium and vitamin

D deficiency among people with severe

obesity, it has been suggested that pre-op lab

testing include vitamin D and PTH levels. If

vitamin D deficiency is found, a possible dose

could be 50,000 IU of ergocalciferol (oral) weekly

for about 8 weeks.

Suggestions for Calcium and Vitamin D

Supplementation Post-Op WLS

Based upon the current research, in accordance

with my team at Johns Hopkins Bayview

Medical Center, I recommend the following

general guidelines, with the need to always individualize

the treatment plan based upon labs,

comorbidities, such as chronic kidney disease

(CKD) and any other factors that may influence

the risk for calcium and

Calcium

Adjustable gastric banding

bypass.

at 1500mg

600mg for optimal absorption; taken separately

from multivitamin

Duodenal switch.

2400mg

600mg at a time; apart from multivitamin

minerals and

Exception:

take calcium citrate (per the National Kidney

Foundation’s Kidney Disease Outcomes Quality

Initiative [K

.org for details), since this is contraindicated due

to the increased risk for aluminum toxicity.

Calcium acetate is not pH-dependent and thus

is recommended in place of calcium citrate, with

doses of elemental calcium same as above. No

standard multivitamin (MVI) for these patients,

but rather renal MVI

fat-soluble vitamin toxicity (vitamin A) risk.

Vitamin D

Vitamin D intake of approximately 2000 IU

may be achieved with proper selection of calcium

and multivitamin supplements. As mentioned

earlier, low vitamin D levels may be

supplemented with 50,000 IU per week for approximately

8 weeks, although much higher doses,

and much longer supplementation regimen,

may be required for duodenal switch patients,

which has been found throughmyclinical practice

and corroborated by colleagues with extensive

experience with duodenal switch patients.

Conclusion

Although there have beenmany studies looking

at calcium and vitamin D levels and needs, both

pre- and post-op among individuals seeking

weight loss surgery, more research needs to be

completed,amongall the surgeries, tomore clearly

delineate whether additional calcium supplementation

can attenuate bone resorption, and at

what level calcium supplementation might be

harmful, such as among patients with CKD or at

risk for it. VitaminDsupplementation seems to be

helpful and indicated for many patients, both preand

post-op, but additional research may further

elucidate the mechanisms of deficiency among

those with severe obesity, and how best to decrease

the risk forbonedisease amongourpatients.

References

1. Coates PS, Fernstrom JD, Fernstrom MH, Schauer PR,

Greenspan SL. Gastric bypass surgery for morbid

obesity leads to an increase in bone turnover and a

decrease in bone mass. J Clin Endocrinol Metab 2004;

89:1061–1065.

2. Recker RR. Calcium absorption and achlorhydria.

N Engl J Med 1985;313:70–73.

3. Kenny AM,

loading with calcium citrate or calcium carbonate on

bone turnover in postmenopausal women. Osteoporos

Int 2004;4:290–294.

4. Sakhaee K,

a comparison of calcium citrate with calcium

carbonate. Am J Ther 1999;6:313–321.

5. Goode LR,

effects of dietary calcium and vitamin D. Obes Res

2004;12:40–47.

6. Collazo-Clavell ML,

Y gastric bypass. Endocr Pract 2004;10:195–198.

7. Hamoui N,

parathyroid hormone in patients with morbid obesity

and after bariatric surgery. Arch Surg 2003;138:891–897.

8. Buffington CK,

morbidly obese. Obes Surg 1993;3:421–424.

9. Bell NH,

D-endocrine system in obese subjects. J Clin Invest

1985;76:370–373.

302 CLINICAL Q&A

Bariatric Nursing, vol. 3, no. 4, 2008

10. Compston JE,

in gross obesity. Am J Nut 1981;34:

2359–2363.

11. Wortsman J,

D in obesity. Am J Nutr 2000;72:690–693.

12. Hey H,

and changes in circulating vitamin D metabolism following

jejunoileal bypass. Int J Obes 1982;6:473–479.

13. Flancbaum L,

of patients undergoing Roux-en Y gastric bypass for

morbid obesity. J Gastrointest Surg 2006;10:1033–1037.

Margaret Furtado, MS, RD, LDN

Johns Hopkins Bayview Medical Center

Answer 2

Vitamin D deficiency is common in morbid

obesity and is frequently found after weight

loss surgery. Vitamin D is a fat-soluble vitamin,

and as such it deposits in fatty tissues. It

may be less available to the body by morbidly

obese persons because of the deposition in fatty

tissues, leading to less bioavailability to the

body. Slightly greater than half of preoperative

weight loss surgery patients may have a deficit

of vitamin D before bariatric surgery.

After bypass surgery, patients consume an

average of only 50% of the RDA for vitamin D

in the postoperative diet. The recommended

daily supplementation levels are 1500–1700mg

calcium citrate and 800 IU vitamin D daily.

Combined with a decreased calcium absorption

after surgery, bone demineralization begins at

a slow pace thatmaytakemanyyears to manifest

from a clinical standpoint, revealing osteoporosis

or secondary hyperparathyroidism.

Vitamin D is responsible for calcium homeostasis,

required for preservation of bone mineralization

and prevention of osteopenia and

osteoporosis. Vitamin D regulates calcium absorption

in the gut and resorption by the

kidney and regulates bone remodeling. There

are two main sources of vitamin D: ergocalciferol

and cholecalciferol. Ergocalciferol is

available in food and is absorbed through the

small intestine as a fat-soluble vitamin. Foods

high in vitamin D include fatty fish, liver,

and egg yolks, as well as fortified foods such

as milk, juice, margarine, butter, cereal, and

pasta. Vitamin D absorption occurs in the

proximal small intestine. Cholecalciferol is produced

in the skin by ultraviolet radiation of 7-

dehydrocholesterol.

Patients whose vitamin D levels are in the

lower end of the normal range may already be

deficient in the vitamin.

25(OH) vitamin D level should be kept above

30 ng

are similar to hyperparathyroidism. Patients

may present with moderately severe musculoskeletal

pain, proximal symmetric muscle weakness,

and muscle wasting.

We recommend blood work to assess for

adequacy of vitamin D levels be performed

preoperatively and annually after surgery. Deficiencies

reveal reduced 25(OH) vitamin D,

calcium, and phosphate levels, increased parathyroid

levels, normal serum creatine kinase

(CK) and possible increased alkaline phosphatase

levels. Bone density scans may reveal decreased

bone density. Treatment of vitamin D

deficiency is accomplished with administration

of oral calciferol 50,000 IU once weekly

for 8 weeks, followed by repeat blood work and

maintenance therapy.

References

1. Nelson ML, Bolduc LM, Toder ME, Clough DM, Sullivan

SS. Correction of vitamin D deficiency after Roux

en Y gastric bypass surgery. Surg Obes Relat Dis 2007

Jul-Aug;3(4):434–437.

2. Parkes E. Nutritional management of patients after

bariatric surgery. Am J Med Sci 2006:331(4):207–213.

3. Haney RP. Functional indices of vitamin D status and

ramifications of vitamin D deficiency. Am J Clin Nutr

2004:80(Suppl):1706–1709.

Hilary S. Blackwood, RN, ACNP-CS

Duke Weight Loss Surgery Center

Address reprint requests to:

Hilary S. Blackwood, RN, ACNP-CS

Duke Weight Loss Surgery Center

3116 N. Duke Street

Durham, NC 27704

E-mail:

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