Viele Menschen, die dialysepflichtig sind, haben wenig oder keine
Urinausscheidung und können ihren Volumenstatus nicht ohne die Dialyse
regulieren. Ebenso fehlt die Ausscheidung von Kalium und Phosphat über die
Nieren. Beide Elektrolyte im Normbereich zu halten, ist eine Herausforderung.
Die Ernährung bei Dialyse ist komplex und Mangelernährung häufig. In diesem
Artikel werden die Hintergründe sowie aktuelle Studien vorgestellt.
Abstract
Dietary recommendations for patients on dialysis are changing as our understanding
of
enteral microbiotal metabolism and bioavailability of nutrients from food improves.
A diet low in phosphate and potassium is recommended for patients on hemodialysis.
However, the absolute content does not reflect bioavailability: How much phosphate
or
potassium is taken up depends on food source (plant vs. animal) and to which grade
it is
processed. While both are nearly 100% bioavailable from industrially processed foods
(additives such as dipotassium-phosphate and other salts), a much lower proportion
is
taken up from unprocessed plant foods high in fibre (ca. 20–40%). The DIET-HD study
showed no significant association between dietary potassium and serum potassium in
>
8 000 dialysis patients; and those with the highest low-processed, fresh plant-food
consumption have the best survival. Dietary fibre improves colon transit time and
thereby lessens symptoms of constipation. A diet low in sodium improves blood pressure
and volume management in dialysis patients. The energy and protein requirements on
dialysis are high: 25–35 kcal and 1–1,2 g protein per kg body weight per day (in
relation to “ideal” body weight, if patient is overweight). Protein energy wasting
is
associated with higher stages of kidney disease, and malnutrition is associated with
worse survival on dialysis. Nutritional status should be assessed on a regular basis
using validated scores, and malnutrition should be addressed and treated.
Schlüsselwörter
Ernährung - Dialyse - Ballaststoffe - Mangelernährung - Phosphat
Keywords
Nutrition - dialysis - dietary fibre - malnutrition - phosphate
