Hyperparathyroidism, Serum Phosphorus and Dietary Intake in Hemodialysis Patients: Is There a Novel Relationship?

The management of hyperparathyroidism (intact parathyroid hormone (iPTH) serum levels > 585 pg/mL), frequently focuses on the appropriate control of mineral and bone markers, with the decrease in serum and dietary phosphorus as two of the targets. We aimed to investigate the association between iPTH, serum phosphorus levels and dietary intake. This was a cross-sectional, multicenter, observational study with 561 patients on hemodialysis treatment. Clinical parameters, body composition and dietary intake were assessed. For the analysis, patients were divided into three groups: (a) iPTH < 130, (b) iPTH between 130 and 585 and (c) iPTH > 585 pg/mL. The association between PTH, serum phosphorus and dietary intake was analyzed using linear regression models. In the whole sample, 23.2% of patients presented an iPTH > 585 pg/mL. Patients with higher iPTH levels were those with longer HD vintage and lower ages, higher serum phosphorus, serum calcium, Ca/P product, albumin and caffeine intake, and a lower dietary intake of phosphorus, fiber, riboflavin and folate. Higher serum phosphorus predicted higher iPTH levels, even in the adjusted model. However, lower dietary phosphorus and fiber intake were predictors of higher iPTH levels, including in the adjusted model. Our results bring new data to the relationship between dietary intake and iPTH values. Despite higher serum phosphorus being observed in patients with HPTH, an opposite association was noted regarding dietary phosphate and fiber.

Mediterranean Diet: A Dietary Pattern Related to Nutritional Benefits for Hemodialysis Patients.

OBJECTIVES: In adults with chronic kidney disease, not on dialysis, there is a recent recommendation suggesting the prescription of a Mediterranean diet pattern but there is still no evidence to suggest a specific dietary pattern for hemodialysis (HD) patients. The aim of this study was to identify dietary patterns in HD patients and analyze their relationship with nutritional status, physical activity, and survival. DESIGN AND METHODS: This was a longitudinal prospective multicenter study with 12 months of follow-up that included 582 HD patients from 37 dialysis centers. Clinical parameters, dietary intake, and physical activity were assessed. Dietary patterns were derived from principal component analysis. A p-value lower than 0.05 was considered statistically significant. RESULTS: Three different dietary patterns were identified: "Mediterranean," "Western," and "low animal protein." Patients in the Mediterranean pattern group showed higher intakes of protein (P = .040), omega 3 fatty acids (P < .001), vitamins B12 (P < .001), B6 (P < .001), C (P < .001), D (P < .001), folic acid (P < .001) and presented a higher practice of moderate physical activity (P = .010). Despite the lower number of deaths that occurred in the Mediterranean dietary pattern group, we did not observe a statistically significant lower mortality risk (P = .096). CONCLUSIONS: The Mediterranean style pattern was associated with a better nutritional intake profile and lifestyle related factors such as a higher practice of moderate physical activity in HD patients.

Zinc Deficient Intake in Hemodialysis Patients: A Path to a High Mortality Risk.

BACKGROUND: Zinc is essential for human nutrition and plays an important role in hemodialysis (HD) patients. The aim of this study is to analyze the relationship between zinc intake and mortality in HD patients. METHODS: This is a longitudinal, prospective, multicenter study with 582 HD patients from 37 dialysis centers. We recorded clinical and body composition parameters. Dietary intake and physical activity data were obtained using the Food Frequency Questionnaire and International Physical Activity Questionnaire. All statistical tests were performed using SPSS 24.0 software. A P value lower than 0.05 was considered statistically significant. RESULTS: Patients' mean age was 67.8 ± 17.7 years and median HD vintage was 65 (43-104) months. About 53.6% of the patients presented a deficient daily intake of zinc. Patients with the highest zinc intake were those who had a higher lean tissue index (P = .022), energy (P < .001), and protein (p = .022) intakes. Zinc intake was positively correlated with energy (r = 0.709) and protein intake (r = 0.805) and negatively correlated with the malnutrition screening tool score (r = -0.087). A higher energy, protein, and lower carbohydrates intake, as well as lower HD vintage and higher lean tissue index were predictors of zinc intake. A higher mortality risk was observed in patients with zinc intake below the recommended values, even after the adjustment for age, presence of diabetes, gender, dialysis vintage, albumin, lean tissue index, energy intake/kilogram, and level of physical activity (P = .021). CONCLUSION: There is a high prevalence of HD patients with an inadequate zinc intake, which is related to worse nutritional and body composition parameters and with a higher mortality risk.

Potassium Intake-(Un)Expected Non-Predictor of Higher Serum Potassium Levels in Hemodialysis DASH Diet Consumers.

As high serum potassium levels can lead to adverse outcomes in hemodialysis (HD) patients, dietary potassium is frequently restricted in these patients. However, recent studies have questioned whether dietary potassium really affects serum potassium levels. The dietary approaches to stop hypertension (DASH) diet is considered a healthy dietary pattern that has been related to lower risk of developing end-stage kidney disease. The aim of this study was to analyze the association between a dietary pattern with high content of potassium-rich foods and serum potassium levels in HD patients. This was an observational, cross-sectional, multicenter study with 582 HD patients from 37 dialysis centers. Clinical and biochemical data were registered. Dietary intake was obtained using the Food Frequency Questionnaire. Adherence to the DASH dietary pattern was obtained from Fung's DASH index. All statistical tests were performed using SPSS 26.0 software. A p-value lower than 0.05 was considered statistically significant. Patients' mean age was 67.8 ± 17.7 years and median HD vintage was 65 (43−104) months. Mean serum potassium was 5.3 ± 0.67 mEq/L, dietary potassium intake was 2465 ± 1005 mg/day and mean Fung´s Dash Index was 23.9 ± 3.9. Compared to the lower adherence to the DASH dietary pattern, patients with a higher adherence to the DASH dietary pattern were older (p < 0.001); presented lower serum potassium (p = 0.021), serum sodium (p = 0.028), total fat intake (p = 0.001) and sodium intake (p < 0.001); and had higher carbohydrate intake (p < 0.001), fiber intake (p < 0.001), potassium intake (p < 0.001), phosphorus intake (p < 0.001) and body mass index (p = 0.002). A higher adherence to this dietary pattern was a predictor of lower serum potassium levels (p = 0.004), even in the adjusted model (p = 0.016). Following the DASH dietary pattern, which is rich in potassium, is not associated with increased serum potassium levels in HD patients. Furthermore, a higher adherence to the DASH dietary pattern predicts lower serum potassium levels. Therefore, generalized dietary potassium restrictions may not be adequate, at least for those with a DASH diet plan.

Dietary Intake, Body Composition, and Clinical Parameters: Associations Between the Level and Type of Physical Activity in Hemodialysis Patients.

BACKGROUND: Physical inactivity and muscle wasting potentiate each other and are highly prevalent among hemodialysis (HD) patients. The authors evaluated the association between physical activity (PA), clinical, nutritional, and body composition parameters in HD patients. METHODS: Multicenter cross-sectional study with 581 HD patients. Clinical, body composition, dietary intake, and PA data were recorded. For the analysis, patients were divided into active (follow World Health Organization recommendations) and inactive groups. RESULTS: A total of 20% of the patients followed World Health Organization recommendations on PA. Differences between physically active and physically inactive patients were observed in age, biochemical parameters and total body water, intracellular water, lean tissue index (LTI), body cell mass, energy, and protein intake. PA was a predictor of higher LTI, body cell mass, and energy intake independently of age, gender, presence of diabetes, dialysis adequacy, and dialysis vintage. Controlling for the effect of age, walking and vigorous PA were positively correlated with energy and protein intake. Vigorous PA was also positively correlated with LTI. CONCLUSION: The PA is a predictor of higher LTI, body cell mass, and energy intake. Vigorous PA is associated with an improved body composition and dietary pattern, whereas walking seems to be also associated with a favorable nutritional status.