Singer Richard, Rhodes Helen C, Chin George, Kulkarni Hemant, Ferrari Paolo
School of Medicine and Pharmacology, University of Western Australia and Department of Nephrology, Fremantle Hospital, Perth, Western Australia, Australia.
Nephrology (Carlton). 2008 Feb;13(1):17-22. doi: 10.1111/j.1440-1797.2007.00857.x.
An adequate total body pool of ascorbate is essential for optimum health in humans. Requirements for ascorbate are increased in peritoneal dialysis (PD) patients most likely due to a combination of poor nutrition and increased dialysate losses.
We measured serum ascorbate levels in 45 clinically stable PD patients to assess the prevalence of ascorbate insufficiency (level between 2 and 4 mg/L) and deficiency (level <2 mg/L). We also assessed the efficacy of subsequent supplementation and patients' adherence to the prescribed supplementation. All patients were advised on commencement of dialysis to take a multivitamin tablet containing 100-120 mg ascorbate.
Eighteen (41%) PD patients were regularly taking ascorbate-containing multivitamins, while 27 (59%) patients did not take ascorbate supplements. Serum ascorbate levels ranged from <0.2 to 41 mg/L, with wide variations in serum ascorbate at any given intake level. Ascorbate deficiency was present in 1/3 of the current PD population (44% of patients not taking supplements and in 16% of those on supplements), although none of the patients demonstrated clinical manifestations of scurvy. Targeted supplementation of ascorbate insufficient patients increased the median serum ascorbate level from 1.7 mg/L (IQR 1.2-2.2) to 22.5 mg/L (IQR 16.7-32.9).
Our results show that, in PD patients, ascorbate deficiency is common and can readily be identified with serum ascorbate measurements. Oral supplements in the form of inexpensive multivitamin preparations restore adequate serum ascorbate levels in the majority of these patients. We therefore suggest measurement of ascorbate levels in all PD patients at the commencement of dialysis with a target level in the normal range (4-14 mg/L).
充足的全身抗坏血酸储备对于人类的最佳健康至关重要。腹膜透析（PD）患者对抗坏血酸的需求增加，这很可能是由于营养不良和透析液损失增加共同导致的。
我们测量了45例临床稳定的PD患者的血清抗坏血酸水平，以评估抗坏血酸不足（水平在2至4mg/L之间）和缺乏（水平<2mg/L）的患病率。我们还评估了后续补充的效果以及患者对规定补充剂的依从性。所有患者在开始透析时都被建议服用含有100 - 120mg抗坏血酸的复合维生素片。
18例（41%）PD患者定期服用含抗坏血酸的复合维生素，而27例（59%）患者未服用抗坏血酸补充剂。血清抗坏血酸水平范围为<0.2至41mg/L，在任何给定摄入水平下血清抗坏血酸都有很大差异。在当前的PD人群中，三分之一存在抗坏血酸缺乏（未服用补充剂的患者中有44%，服用补充剂的患者中有16%），尽管没有患者表现出坏血病的临床表现。针对性地补充抗坏血酸不足的患者使血清抗坏血酸水平中位数从1.7mg/L（四分位间距1.2 - 2.2）提高到22.5mg/L（四分位间距16.7 - 32.9）。
我们的结果表明，在PD患者中，抗坏血酸缺乏很常见，通过血清抗坏血酸测量可以很容易地识别出来。以廉价复合维生素制剂形式的口服补充剂可使大多数此类患者的血清抗坏血酸水平恢复到足够水平。因此，我们建议在透析开始时测量所有PD患者的抗坏血酸水平，目标水平为正常范围（4 - 14mg/L）。
