Role of low protein diet in management of different stages of chronic kidney disease - practical aspects

BACKGROUND: Chronic kidney disease (CKD) is a worldwide public health problem and more so in India. With limited availability and high cost of therapy, barely 10 % of patients with incident end stage renal disease (ESRD) cases get treatment in India. Therefore, all possible efforts should be made to retard progression of CKD. This article reviews the role of low protein diet (LPD) in management of CKD subjects and suggests how to apply it in clinical practice. DISCUSSION: The role of LPD in retarding progression of CKD is well established in animal experimental studies. However, its role in human subjects with CKD is perceived to be controversial based on the modification of diet in renal disease (MDRD) study. We believe that beneficial effect of LPD could not be appreciated due to shorter duration of follow-up in the MDRD study. Had the study been continued longer, it may have been possible to appreciate beneficial effect of LPD. It is our contention that in all cases of CKD that are slowly progressive, LPD can significantly retard progression of CKD and delay the need for renal replacement therapy (RRT). To be able to apply LPD for a long period, it is important to prescribe LPD at earlier stages (1,2,3) of CKD and not at late stage as recommended by KDIGO guidelines. Many clinicians are concerned about worsening nutritional status and hence reluctant to prescribe LPD. This actually is true for patients with advanced CKD in whom there is spontaneous decrease in calorie and protein intake. In our experience, nutritional status of patients in early stages (1,2,3) of CKD is as good as that of healthy subjects. Prescribing LPD at an early stage is unlikely to worsen status. SUMMARY: The role of LPD in retarding progression of CKD is well established in animal experimental studies. Even in human subjects, there is enough evidence to suggest that LPD retards progression of CKD in carefully selected subjects. It should be prescribed to those with good appetite, good nutritional status and a slowly progressive CKD at an early stage (stage 1,2,3). It may also be prescribed at stage 4 & 5 of CKD if the appetite and nutritional status are good.