Validation of the Spanish version of the Liver Disease Quality of Life questionnaire in transplant patients

OBJECTIVE

Our aim was to validate Spanish and Catalan versions of the Liver Disease Quality of Life questionnaire (LDQOL) for use in liver transplant patients.

METHODS

The LDQOL consists of the SF-36 generic measure of health-related quality of life (HRQOL) and 12 disease-specific dimensions for liver disease patients. The Spanish and Catalan versions of the questionnaire were administered to 138 patients with a liver transplant. Cronbach's alpha coefficients (CAC) were used to test the internal consistency of disease-specific scales. Test-retest reliability was calculated using the Intraclass Correlation Coefficient (ICC) in a sub-group of 41 patients who completed the questionnaire on two occasions 1 to 2 weeks apart. Validity was analysed by determining the instrument's capacity to discriminate between patient groups classified according to years since transplant, disease etiology, and symptom severity. Ceiling and floor effects were also calculated.

RESULTS

Internal consistency in the disease-specific dimensions was acceptable or good (CACs 0.60-0.97), as was test-retest reliability in all dimensions (statistically significant CCIs of 0.62-0.89), except the symptoms dimension (CCI=0.46, P<.05). Few differences were found in disease-specific dimension scores between patients classified according to number of years since transplant or etiology, but differences were found in some dimensions according to symptom severity. Moderate to severe ceiling effects were found in several disease-specific dimensions.

CONCLUSIONS

The Spanish and Catalan versions of the LDQOL may be useful for measuring HRQOL in this population, though it will be important to investigate further the instrument's sensitivity to change.

NaFe3+EDTA as a food fortificant: influence on zinc, calcium and copper metabolism in the rat

The general acceptance of NaFe3+EDTA for food Fe fortification has been partly restricted by concern over the influence of EDTA on the metabolism of other nutritionally important trace elements and minerals. We have investigated the influence of NaFe3+EDTA, and of increasing dietary levels of Na2EDTA, on Zn, Cu and Ca metabolism in rats fed on Zn-sufficient and Zn-deficient soya-bean-isolate-based diets. With the Zn-deficient diets, changing the dietary Fe compound from FeSO4 to NaFe(3+)-EDTA significantly (P < 0.05) increased mean apparent Zn absorption from 50.2 to 67.4%, urinary Zn excretion from 2.0 to 4.0% of intake, and Zn retention from 48.2 to 63.4%. Increasing the dietary EDTA level to 1000 mg/kg further increased Zn absorption to 78.1%, urinary Zn excretion to 15.6% of intake and Zn retention to 62.5%. Increased Zn retention was accompanied by a significant increase in weight gain indicating that the extra Zn was available for normal metabolic processes. With rats fed on the Zn-sufficient diet, NaFe3+EDTA and Na2EDTA similarly increased the absorption, urinary excretion and retention of Zn but to a lesser extent. NaFe3+EDTA, however, had no influence on the absorption, urinary excretion and retention of Cu and Ca, and additional Na2EDTA caused only minor increases in Cu absorption and retention and in the urinary excretion of Ca. We conclude that using NaFe3+EDTA as a food fortificant would have no detrimental effect on the metabolism of Zn, Cu and Ca and, in some situations, could improve Zn absorption and retention from low-bioavailability diets.