Effects of low protein diet supplemented with ketoanalogues on kidney function and nutritional outcomes in a nonagenarian population with advanced chronic kidney disease: a pilot study.

BACKGROUND

Ageing leads to an increase in the incidence of chronic diseases, including chronic kidney disease (CKD). The increasing proportion of elderly people with reduced renal function draws attention to a sub-population of patients for whom an alternative approach to traditional pharmacological and dietary treatment may be needed. The low-protein diet (LPD) in subjects with CKD helps control complications and may contribute to slowing the progression of the disease. In the follow-up during the conservative phase, nutritional status and the LPD are key points. Of interest, ketoanalogues (KAs) in combination with a LPD significantly reduces the progression to end-stage kidney disease. The aim of this pilot study is to determine the impact at 12 months of LPD supplemented with essential amino acids (EAA) and KAs in a population of 21 over-90-year-olds with advanced CKD in the conservative phase.

METHODS

The protein intake of the LPD was 0.6 g/kg body weight/day. Anthropometric measurements and biochemical parameters were monitored at baseline and after 12 months of dietary intervention. The Kidney Failure Risk Equation (KFRE) was used to predict the risk of end stage renal disease.

RESULTS

Significant change in GFR (from 18.04±1.31 to 24.30±2.09 mL/min, P<0.001), azotemia (from 122.38±19.16 to 70.19±15.00 mg/dL, P<0.001) and KFRE score at 2 years (from 33.67±3.88 to 15.09±3.03%, P<0.001) and at 5 years (from 71.94±5.13 to 39.76±6.60% at 5 years, P<0.001). Laboratory parameters (azotemia, albumin, total protein, total cholesterol, transferrin, Hb, PTH, HbA1c, TSAT, CRP) improved. Two patients were hospitalized during the observation period, no cardiovascular events or deaths were reported.

CONCLUSIONS

LPD supplemented with EAA and KAs has proven to be a safe and effective tool in the conservative treatment of the over-aged with advanced CKD. Dietary treatment improves renal function and management of complications, reducing the risk of terminal uremia and initiation of replacement treatment by not exposing patients to the risk of malnutrition.