Plant-based diets, insulin sensitivity and inflammation in elderly men with chronic kidney disease

Abstract

Background In persons with CKD, adherence to plant-based diets is associated with lower risk of CKD progression and death, but underlying mechanisms are poorly characterized. We here explore associations between adherence to plant-based diets and measures of insulin sensitivity and inflammation in men with CKD stages 3–5. Methods Cross-sectional study including 418 men free from diabetes, aged 70–71 years and with cystatin-C estimated glomerular filtration rate (eGFR) <60 mL/min/1.73m2 and not receiving kidney-specific dietetic advice. Information from 7-day food records was used to evaluate the adherence to a plant-based diet index (PBDi), which scores positively the intake of plant-foods and negatively animal-foods. Insulin sensitivity and glucose disposal rate were assessed with the gold-standard hyperinsulinemic euglycemic glucose clamp technique. Inflammation was evaluated by serum concentrations of C-reactive protein (CRP) and interleukin (IL)-6. Associations were explored through linear regression and restricted cubic splines. Results The majority of men had CKD stage 3a. Hypertension and cardiovascular disease were the most common comorbidities. The median PBDi was 38 (range 14–55). Across higher quintiles of PBDi (i.e. higher adherence), participants were less often smokers, consumed less alcohol, had lower BMI and higher eGFR (P for trend <0.05 for all). Across higher PBDi quintiles, patients exhibited higher insulin sensitivity and lower inflammation (P for trend <0.05). After adjustment for eGFR, lifestyle factors, BMI, comorbidities and energy intake, a higher PBDi score remained associated with higher glucose disposal rate and insulin sensitivity as well as with lower levels of IL-6 and CRP. Conclusion In elderly men with non-dialysis CKD stages 3–5, adherence to a plant-based diet was associated with higher insulin sensitivity and lower inflammation, supporting a possible role of plant-based diets in the prevention of metabolic complications of CKD. Graphic abstract

Association of plant‐based diet index with inflammatory markers and sleep quality in overweight and obese female adults: A cross‐sectional study

“…52 In another cross-sectional study of elderly men with chronic kidney disease (CKD), a higher adherence to a plantbased diet was associated with higher insulin sensitivity and lower levels of CRP and IL-6. 53 Our results were also in accordance with the studies that investigated the relationship of plant-based dietary patterns including the Mediterranean diet with inflammation. [54][55][56] The Mediterranean diet is characterised by high consumption of fruits, vegetables, MUFAs mainly from olive oil, nuts, legumes, whole grain cereals, low intake of red or processed meat and a low-to-moderate consumption of red wine during meals.…”

“…Besides, women with increased uPDI scores had significant increases in hs‐CRP and IL‐6 concentration 52 . In another cross‐sectional study of elderly men with chronic kidney disease (CKD), a higher adherence to a plant‐based diet was associated with higher insulin sensitivity and lower levels of CRP and IL‐6 53 …”

Sarcopenia in chronic kidney disease: what have we learned so far?

“…However, interventional studies in patients with CKD (stages 3–5 not on dialysis) evaluating the use of controlled protein intake (moderate to low protein diets—0.6 to 0.8 g/kg/day, or very low protein diet—0.3 to 0.4 g/kg/day supplemented with amino acids or their nitrogen-free keto-analogues) and with adequate energy intake have shown positive findings in elderly CKD patients in preserving good nutritional status [ 90 – 93 ], postponing the beginning of dialysis therapy [ 90 ], lowering all-cause mortality [ 91 ], good adherence to a moderate restriction in protein intake (0.8 g/kg/day) and increasing serum albumin [ 92 ] and better quality of life [ 93 ]. More recently, not only the protein amount, but the adherence to higher scores of plant-based diet in elderly men with CKD stages 3–5 was associated with better insulin sensitivity and lower inflammatory markers, supporting the concept that the source and type of protein also plays an important role and has the potential to offer benefits to elderly with CKD [ 94 ]. Altogether, these findings are suggestive that controlling the protein intake (0.6–0.8 g/kg/day) in elderly patients with CKD 3–5 can be beneficial but only if an adequate amount of energy is provided as this is needed to prevent impaired protein degradation and the risk of muscle wasting [ 95 ].…”

Low Protein Diets and Plant-Based Low Protein Diets: Do They Meet Protein Requirements of Patients with Chronic Kidney Disease?

“…In addition, a vegetable-rich diet is helpful for the prevention, treatment and reversal of the major comorbidities associated with CKD, such as diabetes, hypertension and CVD [ 77 ]. Overall, available studies have shown that plant-based diets are also helpful to prevent and treat several CKD complications [ 78 , 79 ]. Adherence to a plant-based diet has been associated with all-cause mortality [ 78 ].…”