Ricerc@Sapienza

A relationship between dysbiotic gut microbiome and chronic kidney disease (CKD) has
been recently documented; it contributes to CKD-related complications, including cardiovascular
disease. Aim: We tested how a low-protein diet (LPD)—with or without oral inulin supplementation
as a prebiotic—modulates some inflammatory, atherosclerosis and endothelial dysfunction indices
and nutritional markers, as well as psychocognitive functions in CKD patients. We conducted a
prospective, case–control study on CKD patients on conservative therapy, divided in two groups:
the intervention group treated with LPD (0.6 g/kg/day) plus inulin (19 g/day) and a control group
treated with LPD without inulin, for six consecutive months. Clinical and hematochemical parameters
as well as instrumental, and psychocognitive assessments (by SF-36 survey and MMSE, HAM-D,
BDI-II) were recorded in all the participants at baseline (T0), at three months (T1) and at six months
(T2). A total of 41 patients were enrolled: 18 in the intervention group and 23 in the control group.
At T2, in both groups, we observed a significant reduction of serum nitrogen and phosphorus
(p 0.01) and serum uric acid (p 0.03), and an improvement in metabolic acidosis (bicarbonates,
p 0.01; base excess, p 0.02). Moreover, at T2 the intervention group showed a reduction in
serum insulin (p = 0.008) and fasting glucose levels (p = 0.022), HOMA-IR (p = 0.004), as well as
lower total serum cholesterol (p = 0.012), triglycerides (p = 0.016), C-reactive protein (p = 0.044) and
homocysteine (p = 0.044) and higher HDL (p < 0.001) with respect to baseline. We also observed a
significant amelioration of some quality of life and functional status indices (SF-36 survey) among
the intervention group compared to controls, without a significant improvement in the cognitive
state (MMSE). On the other hand, an amelioration in mood (by HAM-D and BDI-II) was found
in the intervention group and in controls (only by BID-II). In conclusion, LPD in association with
oral inulin supplementation improved glycemic and lipid metabolism and ameliorated the systemic
inflammatory state, likely reducing cardiovascular risk in CKD patients and this may represent a
promising therapeutic option, also improving quality of life and mood.