Very low protein diet is anti hypertensive

Kidney International (2007) 71, 245–251. doi:10.1038/sj.ki.5001955; published online 11 October 2006

Very low protein diet supplemented with ketoanalogs improves blood pressure control in chronic kidney disease

V Bellizzi¹, B R Di Iorio¹, L De Nicola², R Minutolo², P Zamboli², P Trucillo², F Catapano², C Cristofano³, L Scalfi⁴ and G Conte² on behalf of the ERIKA Study-group

Abstract

Blood pressure (BP) is hardly controlled in chronic kidney disease (CKD).

We compared the effect of very low protein diet (VLPD) supplemented with ketoanalogs of essential amino acids (0.35 g/kg/day), low protein diet (LPD, 0.60 g/kg/day), and free diet (FD) on BP in patients with CKD stages 4 and 5.

Vegetable proteins were higher in VLPD (66%) than in LPD (48%). LPD was prescribed to 110 consecutive patients; after run-in, they were invited to start VLPD. Thirty subjects accepted; 57 decided to continue LPD; 23 refused either diet (FD group). At baseline, protein intake (g/kg/day) was 0.790.09 in VLPD, 0.780.11 in LPD, and 1.110.18 in FD (P<0.0001).>

After 6 months, protein intake was lower in VLPD than LPD and FD (0.540.11, 0.780.10, and 1.040.21 g/kg/day, respectively; P<0.0001). src="http://www.nature.com/__chars/plus/special/plusmn/black/med/base/glyph.gif" style="border: 0pt none ; vertical-align: baseline;" alt="plusminus">19/8410 to 12816/787 mm Hg (P<0.0001), src="http://www.nature.com/__chars/plus/special/plusmn/black/med/base/glyph.gif" style="border: 0pt none ; vertical-align: baseline;" alt="plusminus">1.1 to 1.81.2; P<0.001). src="http://www.nature.com/__chars/plus/special/plusmn/black/med/base/glyph.gif" style="border: 0pt none ; vertical-align: baseline;" alt="plusminus">32 to 13136 mEq/day; P<0.001).>

At multiple regression analysis (R²=0.270, P<0.0001),>P=0.023) and VLPD prescription (P=0.003), but not to the level of protein intake.

Thus, in moderate to advanced CKD, VLPD has an antihypertensive effect likely due to reduction of salt intake, type of proteins, and ketoanalogs supplementation, independent of actual protein intake.