DEFICIENCY IN 25-hydroxyvitamin D [25(OH)D] is common in CKD. Although the endocrine functions of vitamin D in bone mineral metabolism are well known, the effects of autocrine and paracrine functions on insulin production and resistance, immunity, and CVD are receiving increased attention.

DESPITE INTENSIVE dietary intervention, malnutrition remains prevalent in stage 5 CKD, affecting 20%-70% of all patients. Malnutrition, as evidenced by hypoalbuminemia, is strongly associated with increased morbidity and mortality in this patient population.

IMPAIRED BONE mineral metabolism is prevalent in CKD patients, presenting a special challenge for patients and renal health professionals. By stage 5 CKD, an estimated 50% or more of dialysis patients have bone mineral parameters that exceed evidence-based practice guidelines.

AT PRESENT, almost one fourth of stage 5 CKD patients experience a life-threatening episode of hyperkalemia requiring emergency treatment, according to data cited in a recent article in Seminars in Dialysis (2007;20:431-439). The authors, Nirupama Putcha, MD, and Michael Allon, MD, note that although "many options have been proposed for the prevention of interdialytic hyperkalemia...prevention currently rests largely upon compliance with diet and a thoughtful use of medication regimens."

LOW-PROTEIN diets are a po0tentially useful intervention in slowing CKD progression, though adequate calorie intake is a key to their success.

THE POSITIVE association between obesity and kidney disease (KD) is strongly supported by results of a recent meta-analysis by Wang et al (Kidney Int. 2008;73:19-33) that demonstrate a significantly increased risk for people with BMI greater than the normal range of 18.5-25 kg/m2. Along with CKD, the study also examined the occurrence of renal calculi and kidney cancer. According to the authors, 24.2% and 33.9% of KD cases among American men and women, respectively, could be prevented if overweight and obesity were eliminated.

RENAL HEALTH professionals recognize the detrimental effects of high sodium intake on BP control, congestive heart failure, and fluid balance in CKD patients.

The established practice for preventing urinary calculi is being challenged by results of a recent study (Whitson et al, Urology. 2007;70:634-637), which showed no correlation between urinary citrate levels and urinary pH.

WITH 45% of dialysis patients presenting as a result of diabetic kidney disease or with comorbidity of diabetes, studies are examining blood sugar control as a means to improving outcomes for this large segment of the dialysis population.

DESPITE regular dietary instruction, patients undergoing dialysis have a poor knowledge of dietary phosphorus compared with other nutrients important in CKD, according to researchers at the University of Wisconsin Medical School in Madison.