Malnutrition in the Renal patient
Chronic Kidney Disease is defined as the progressive, permanent and irreversible impairment of renal function.
In some cases, it may result from the progression of various diseases, leading to the loss of the kidney’s glomerular, tubular and endocrine functions. This results in impaired excretion of the end products of metabolism, inadequate elimination of water and electrolytes, and alterations in the secretion of various hormones.
Chronic kidney disease (CKD) worsens slowly over months or years. It is possible that no symptoms are noticed for some time, as the loss of function may be so gradual that symptoms do not appear until the kidneys have almost stopped working.
When CKD is diagnosed, it is important to carry out appropriate monitoring of the patient’s diet, together with proper nutritional education.
Following a personalised, balanced diet adapted to each patient’s needs is of great importance and may also directly influence the progression of the disease.
Normally, in the early stages of CKD, uncomplicated patients have a good appetite and tend to maintain a stable weight. Therefore, their nutritional status, which is determined by the patient’s clinical condition and eating habits, is usually adequate.
As the disease progresses, it is important to monitor the intake of certain nutrients (especially proteins, phosphorus and potassium), while ensuring an optimal intake of macro- and micronutrients so that each patient’s nutritional requirements are met. At this stage of the disease, the intake of nutritional supplements such as essential amino acids, protein modules or complete oral supplements may be recommended to ensure the patient’s needs are met and even to help slow the progression of the disease.
Once renal failure occurs and the patient requires renal replacement therapy (haemodialysis/peritoneal dialysis), nutritional status becomes more vulnerable.
Malnutrition has been diagnosed in 10–70% of patients undergoing haemodialysis. This is due to the loss of essential amino acids during each session and the increased protein–energy wasting. Similarly, in kidney transplant patients, the risk of malnutrition is very high (due to the surgery itself, the state of inflammation and immunosuppression, etc.).
It is important to carry out an appropriate, personalised nutritional approach, supplementing the patient in cases of malnutrition and meeting their energy and protein requirements, thereby improving the patient’s nutritional status, overall quality of life and the development of certain comorbidities.