Organic and inorganic dietary phosphorus and its management in chronic kidney disease

Dietary phosphorus control is often a main strategy in the management of patients with chronic kidney disease. Dietary protein is a major source of phosphorus intake. Recent data indicate that imposed dietary phosphorus restriction may compromise the need for adequate protein intake, leading to protein-energy wasting and possibly to increased mortality. The two main sources of dietary phosphorus are organic, including animal and vegetarian proteins, and inorganic, mostly food preservatives. Animal-based foods and plant are abundant in organic phosphorus. Usually 40% to 60% of animal-based phosphorus is absorbed; this varies by degree of gastrointestinal vitamin-D-receptor activation, whereas plant phosphorus, mostly associated with phytates, is less absorbable by human gastrointestinal tract. Up to 100% of inorganic phosphorus in processed foods may be absorbed; ie, phosphorus in processed cheese and some soda [cola] drinks. A recent study suggests that a higher dietary phosphorus-protein intake ratio is associated with incremental death risk in patients on long-term hemodialysis. Hence, for phosphorus management in chronic kidney disease, in addition to absolute dietary phosphorus content, the chemical structure [inorganic versus organic], type [animal versus plant], and phosphorus-protein ratio should be considered. We recommend foods and supplements with no or lowest quantity of inorganic phosphorus additives, more plant-based proteins, and a dietary phosphorus-protein ratio of less than 10 mg/g. Fresh [nonprocessed] egg white [phosphorus-protein ratio less than 2 mg/g] is a good example of desirable food, which contains a high proportion of essential amino acids with low amounts of fat, cholesterol, and phosphorus

Mental health, depression, and anxiety in patients on maintenance dialysis

Depression and anxiety are among the most common comorbid illnesses in people with end-stage renal disease [ESRD]. Patients with ESRD face many challenges which increase the likelihood that they will develop depression or anxiety or worsen these conditions. These include a general feeling of unwellness; specific symptoms caused by ESRD or the patient's treatment; major disruptions in lifestyle; the need to comply with treatment regimens, including dialysis schedules, diet prescription, and water restriction; ancillary treatments and hospitalizations; and the fear of disability, morbidity, and shortened lifespan. Depression has been studied extensively in patients on maintenance dialysis, and much effort has been done to validate the proper screening tools to diagnose depression and to define the treatment options for patients on maintenance dialysis with depression. Anxiety is less well studied in this population of patients. Evidence indicates that anxiety is also common in maintenance dialysis. More attention should be paid to measuring the incidence and prevalence and developing methods of diagnosis and treatment approaches for anxiety in patients with ESRD. In this review, we attempted to underscore those aspects of depression and anxiety that have not been investigated extensively, especially with regard to anxiety. The interaction between racial/ethnic characteristics of patients on maintenance dialysis with depression and anxiety needs to be studied more extensively, in order to assess better approaches to healthcare for these individuals