The effects of zinc supplementation on serum zinc concentration and protein catabolic rate in hemodialysis patients.
OBJECTIVE
To examine the effect of zinc sulfate supplementation on serum zinc concentrations and protein catabolic rate (PCR) in hemodialysis (HD) patients.


METHODS
Randomized, double-blind, before-after trial.


METHODS
Outpatient dialysis center in a large metropolitan city.


METHODS
Twenty-eight maintenance HD patients were selected. Twenty (15 women, 5 men) subjects completed the study. Subjects were identified for inclusion in the study by the following criteria: a history of low PCR (<0.09 g/kg body weight), HD treatment for a minimum of 6 months, no signs of gastrointestinal disorders, and no record of hospitalizations for reasons other than access complication within the last 3 months.


METHODS
Patients consumed 7.7 pmol zinc sulfate (2,200 microg) or a cornstarch placebo capsule daily for 90 days. In addition, patients completed a 2-day food record representative of 1 dialysis day and 1 nondialysis day.


METHODS
Fasting, predialysis serum samples were collected on days 0, 40, and 90 to determine serum zinc concentration and PCR. Dietary parameters including intake of zinc, protein, and energy were analyzed on Days 0 and 90.


RESULTS
Initial analysis at Day 0 of serum zinc concentration indicated subjects were below the normal range for serum zinc standards (12.2 micromol/L [80 microg/dL]). After supplementation, subjects in the zinc-supplemented group showed significant increases in serum zinc concentrations from 12.2 micromol/L (80 microg/dL) at Day 0 to 15.3 pmol/L (100 microg/dL) at Day 90. A significant positive correlation (r = +0.61) was shown between PCR and serum zinc concentrations at the end of the study. Reported dietary protein intake did not change with zinc supplementation.


CONCLUSIONS
Low serum zinc concentrations are reversible with zinc supplementation. Improvement in serum zinc concentration increases the PCR of HD patients.
Presbyterian Hospital of Dallas, TX, USA.
N A
NA
Jern
A D
AD
VanBeber
M A
MA
Gorman
C G
CG
Weber
G U
GU
Liepa
C C
CC
Cochran
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015930:Diet Records; D004044:Dietary Proteins / Q000008:administration & dosage; D019587:Dietary Supplements; D004311:Double-Blind Method; D002149:Energy Intake; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D011506:Proteins / Q000378:metabolism*; D006435:Renal Dialysis; D014508:Urea; D015032:Zinc / Q000097:blood* / Q000378:metabolism; D019287:Zinc Sulfate / Q000008:administration & dosage*
D004044:Dietary Proteins; D011506:Proteins; D019287:Zinc Sulfate; D014508:Urea; D015032:Zinc