Dietary Phosphate and the Forgotten Kidney Patient: A Critical Need for FDA Regulatory Action.

Careful dietary management that reduces high phosphate intake is recommended to slow the progression of chronic kidney disease (CKD) and prevent complications of CKD and may help reduce chronic disease risks such as incident CKD associated with high phosphate intake in the healthy general population. For patients treated with maintenance dialysis, control of serum phosphorus levels is considered a marker of good care and requires a coordinated plan that limits dietary phosphate intake, uses oral phosphate binders, and provides an adequate dialysis prescription. Even with traditional thrice-weekly hemodialysis or peritoneal dialysis, use of phosphate binders, and a concerted effort to limit dietary phosphate intake, adequately controlled serum phosphorus levels are not possible in all dialysis patients. Efforts to limit phosphate intake are thwarted by the underestimated and unquantified phosphate content of processed foods and some medications due to the hidden presence of phosphate additives or excipients added during processing or drug formulation. Effectively limiting phosphate intake could potentially be achieved through simple US Food and Drug Administration regulatory actions. Mandatory labeling of phosphate content on all packaged foods and drugs would enable identification of healthy low-phosphate foods and medications and permit critically important control of total phosphate intake. Simple changes in regulatory policy and labeling are warranted and would enable better management of dietary intake of phosphate at all stages of kidney disease, as well as potentially reduced health risks in the general population.

A dearth of data: the problem of phosphorus in prescription medications.

A high dietary intake of phosphorus is considered by most to be a significant health threat for dialysis patients. Efforts to include the phosphorus content of foods on the nutrition label in the US have, to date, been fruitless. Another source of phosphorus, largely unrecognized, is prescription medications. These may contain phosphorus as indicated on their package label; the amount is not quantified. We examined the labels of the branded forms of 200 of the most widely prescribed medications in Dialysis Clinic centers in the United States and found that 23 (11.5%) contained phosphorus. A sampling of different doses and manufacturers (generic and branded) of these drugs was analyzed for phosphorus content and found levels as high as 111.5 mg/dose (40 mg paroxetine). Notable were the phosphorus content of a generic 10 mg lisinopril (32.6 mg) and a generic 10 mg amlodipine (40.1 mg). The significant potential for iatrogenic injury accruing from the use of these drugs warrants efforts at remediation. Specific information on the phosphorus content of medications used by dialysis population needs to be made available to the dialysis community.

Iron indices and intravenous ferumoxytol: time to steady-state.

BACKGROUND: The ongoing nature of iron loss in patients receiving hemodialysis makes it difficult to maintain adequate iron stores without supplementation. The effects of ferumoxytol on iron indices have been measured 35 days after baseline, but no study has assessed indices at earlier points in time. OBJECTIVE: To evaluate the time to transferrin saturation (TSAT) and ferritin stabilization, the point at which TSAT and serum ferritin levels can be accurately measured during a 13-treatment period following a loading dose of ferumoxytol. METHODS: Ferumoxytol was administered according to the package insert to 15 adults undergoing hemodialysis. Vital signs were recorded before treatment, 30 and 60 minutes after receiving ferumoxytol, and at the end of treatment to monitor for adverse reactions and hemodynamic instability. Monitoring continued for a 13-treatment period (30 days) after drug administration. Blood was collected throughout the study to measure TSAT, ferritin, hemoglobin (Hb), and C-reactive protein (CRP). RESULTS: TSAT values at 14, 21, and 28 days after drug administration were not significantly different from those at 7 days, signifying that TSAT values stabilized by day 7. Serum ferritin values at day 14 were significantly lower than those 7 days after drug administration (p = 0.028). Although serum ferritin values at days 21 and 28 tended to decrease relative to values at day 14, the differences were not statistically significant. Therefore, it appears that serum ferritin stabilized by day 14 after drug administration. Mean (SD) Hb values at screening and at end of the study were 11.7 (1.0) g/dL and 12.0 (0.9) g/dL, respectively (p = NS). CRP also did not change significantly throughout the study period. CONCLUSIONS: Dialysis patients achieve stable iron indices quickly. TSAT stabilized by day 7 and ferritin stabilized 14 days after a loading dose of ferumoxytol 1 g. Adverse effects were minimal and did not necessitate discontinuation of ferumoxytol.

Phosphorus and potassium content of enhanced meat and poultry products: implications for patients who receive dialysis.

BACKGROUND AND OBJECTIVES: Uncooked meat and poultry products are commonly enhanced by food processors using phosphate salts. The addition of potassium and phosphorus to these foods has been recognized but not quantified. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We measured the phosphorus, potassium, and protein content of 36 uncooked meat and poultry products: Phosphorus using the Association of Analytical Communities (AOAC) official method 984.27, potassium using AOAC official method 985.01, and protein using AOAC official method 990.03. RESULTS: Products that reported the use of additives had an average phosphate-protein ratio 28% higher than additive free products; the content ranged up to almost 100% higher. Potassium content in foods with additives varied widely; additive free products all contained <387 mg/100 g, whereas five of the 25 products with additives contained at least 692 mg/100 g (maximum 930 mg/100 g). Most but not all foods with phosphate and potassium additives reported the additives (unquantified) on the labeling; eight of 25 enhanced products did not list the additives. The results cannot be applied to other products. The composition of the food additives used by food processors may change over time. CONCLUSIONS: Uncooked meat and poultry products that are enhanced may contain additives that increase phosphorus and potassium content by as much as almost two- and three-fold, respectively; this modification may not be discernible from inspection of the food label.

Efficacy of selected complementary and alternative medicine interventions for chronic pain.

Complementary and alternative medicine (CAM) is a group of diverse medical and healthcare systems, therapies, and products that are not presently considered part of conventional medicine. This article provides an up-to-date review of the efficacy of selected CAM modalities in the management of chronic pain. Findings are presented according to the classification system developed by the National Institutes of Health National Center for Complementary and Alternative Medicine (formerly Office of Alternative Medicine) and are grouped into four domains: biologically based medicine, energy medicine, manipulative and body-based medicine, and mind-body medicine. Homeopathy and acupuncture are discussed separately as "whole or professionalized CAM practices." Based on the guidelines of the Clinical Psychology Division of the American Psychological Association, findings indicate that some CAM modalities have a solid track record of efficacy, whereas others are promising but require additional research. The article concludes with recommendations to pain practitioners.

Instrumentation methodology for recording and feeding-back surface electromyographic (SEMG) signals.

The use of biofeedback devices has been plagued by the "garbage in--garbage out" problem since its inception. This paper reviews the basics of how to use biofeedback devices for surface electromyographic applications at each stage in the process from sensors to displays so meaningful information can be gathered and utilized.

A survey of current phantom limb pain treatment in the United States.

A survey of phantom limb pain treatment methods currently used by Veterans Administration hospitals, medical schools, pain clinics, and pain specialists in the United States was carried out to determine which treatments are in use, their success rates as estimated by their users, and experience with unsuccessful treatment methods used by patients prior to referral to the respondent. The combined results of a recent literature search and this survey identified 68 treatment methods of which 50 were commented upon by the survey respondents as being in current use. Only a few treatment methods were even moderately successful when subjected to the criterion of low failure rates after one year. Non-surgical treatment methods were far more successful than surgical ones. A possible treatment regime based on optimizing moderately successful methods is proposed for further study.

Treatment of phantom limb pain with muscular relaxation training to disrupt the pain--anxiety--tension cycle.

Sixteen phantom limb pain patients were treated with a combination of (1) progressive muscle relaxation exercise, (2) feedback of stump and forehead muscle tension, and (3) reassurance about normal phantom sensations and the relationship between anxiety and pain. Fourteen of the patients had chronic pain (average of 12 years) and two were recent amputees (5- and 1-week). At the end of treatment, 8 of the chronic patients showed virtually complete relief from pain, 4 showed significant decreases to a point at which they no longer desired treatment and 2 showed no significant change. Both recent amputees showed complete relief from pain. These changes have been sustained for follow-up period of 6 months to 3 years. The 2 unsuccessful patients did not learn to relax and had strong psychological needs for their pain.