Nutrition Trends in Patients Over the Long Term After Kidney Transplantation

Ultra-Processed Food Consumption, Poorer Nutritional Quality, and Lower Muscle Mass in Immediate and Late Postkidney Transplant Periods

OBJECTIVE

To assess the consumption of ultra-processed foods (UPFs) in the immediate (2 months after transplantation) and late post-transplant (14 months after transplantation) periods among kidney transplant patients and to examine its correlation with nutritional quality and body composition.

DESIGN AND METHODS

A cross-sectional analysis of 96 kidney transplant recipients divided into 2 groups: immediate post-transplant (n = 71) and late post-transplant (n = 25). Sociodemographic, anthropometric, and laboratory data were collected and grouped in a database. Food intake was evaluated by a validated food frequency questionnaire and foods were divided according to the NOVA classification system. The consumption of UPFs was calculated and statistical analyses were performed to evaluate its correlation with nutritional components and body composition.

RESULTS

The consumption of UPFs was 649.4 [420.0-1061.72] kcal/day, accounting for 33.3 ± 11.9% of the total daily energy intake. The immediate post-transplant group showed higher total daily energy and UPFs intake compared to the late post-transplant group (P = .002 and P = .046, respectively), although the energy contribution of UPFs was similar between both groups. UPFs intake was positively correlated with higher percentages of total fat, trans fat, saturated, monounsaturated fat, polyunsaturated fat, starch, and sodium (P < .05 for all analyses). An inverse correlation was observed between UPFs consumption and the percentage of protein and carbohydrates in the food intake (P = .025 and P = .008, respectively). In the immediate post-transplant group, a higher intake of UPFs was correlated with lower muscle mass (r = -0.250, P = .037).

CONCLUSIONS

The findings of this study reveal a pattern of increased consumption of UPFs among kidney transplant patients in comparison to the national average. This higher intake of UPFs was correlated with lower nutritional quality during both periods. Moreover, a significant correlation was observed between UPFs consumption and adverse body composition parameters, specifically in the immediate post-transplant period.

The Impact and Effectiveness of Weight Loss on Kidney Transplant Outcomes: A Narrative Review

Obesity is a worldwide epidemic that leads to several non-communicable illnesses, including chronic kidney disease (CKD). Diet and lifestyle modifications have shown a limited impact in the treatment of obesity. Because the group of end-stage renal disease (ESRD) patients examined in this study had limited access to kidney transplantation (KT), patients with obesity were thought to be at an increased risk of intraoperative and postoperative KT complications. Although bariatric surgery (BS) is now recognized as the gold standard treatment for morbid obesity, its role in ESRD or kidney transplant patients remains unknown. It is critical to know the correlation between weight loss and complications before and after KT, the impact of the overall graft, and patients' survival. Hence, this narrative review aims to present updated reports addressing when to perform surgery (before or after a KT), which surgical procedure to perform, and again, if strategies to avoid weight regain must be specific for these patients. It also analyzes the metabolic alterations produced by BS and studies its cost-effectiveness pre- and post-transplantation. Due to the better outcomes found in KT recipients, the authors consider it more convenient to perform BS before KT. However, more multicenter trials are required to provide a solid foundation for these recommendations in ERSD patients with obesity.

Nutrition Disturbances and Metabolic Complications in Kidney Transplant Recipients: Etiology, Methods of Assessment and Prevention-A Review

Nutrition disturbances occur at all stages of chronic kidney disease and progress with the decrease of the kidney filtration rate. Kidney transplantation (KTx) as the best form of kidney replacement therapy poses various nutritional challenges. Prior to transplantation, recipients often present with mild to advanced nutrition disturbances. A functioning allograft not only relieves uremia, acidosis, and electrolyte disturbances, but also resumes other kidney functions such as erythropoietin production and vitamin D3 metabolism. KTx recipients represent a whole spectrum of undernutrition and obesity. Since following transplantation, patients are relieved of most dietary restrictions and appetite disturbances; they resume old nutrition habits that result in weight gain. The immunosuppressive regimen often predisposes them to dyslipidemia, glucose intolerance, and hypertension. Moreover, most recipients present with chronic kidney graft disease at long-term follow-ups, usually in stages G2-G3T. Therefore, the nutritional status of KTx patients requires careful monitoring. Appropriate dietary and lifestyle habits prevent nutrition disturbances and may improve kidney graft function. Despite many nutritional guidelines and recommendations targeted at chronic kidney disease, there are few targeted at KTx recipients. We aimed to provide a brief review of nutrition disturbances and known nutritional recommendations for kidney transplant recipients based on the current literature and dietary trends.

Dyslipidemia in Renal Transplant Recipients

Dyslipidemia is a frequent complication after kidney transplantation (KT) and is an important risk factor for cardiovascular disease (CVD). Renal transplant recipients (RTRs) are considered at high, or very high, risk of CVD, which is a leading cause of death in this patient group. Despite many factors of post-transplant dyslipidemia, the immunosuppressive treatment has the biggest influence on a lipid profile. There are no strict dyslipidemia treatment guidelines for RTRs, but the ones proposing an individual approach regarding CVD risk seem most suitable. Proper diet and physical activity are the main general measures to manage dyslipidemia and should be introduced initially in every patient after KT. In the case of an insufficient correction of lipemia, statins are the basis for hypolipidemic treatment. Statins should be introduced with caution to avoid serious side-effects (e.g., myopathy) or drug-drug interactions, especially with immunosuppressants. To lower the incidence of adverse effects, and improve medication adherence, ezetimibe in combination with statins is recommended. Fibrates and bile sequestrants are not recommended due to their side-effects and variable efficacy. However, several new lipid-lowering drugs like Proprotein convertase subtilisin/Kexin type9 (PCSK9) inhibitors may have promising effects in RTRs, but further research assessing efficacy and safety is yet to be carried out.

Medical nutritional therapy for renal transplantation in the COVID-19 pandemic

Nutritional therapy is very important at renal transplantation. Nutrition has become more vital for transplantation patients owing to the coronavirus disease 2019 (COVID-19) pandemic. Inadequate nutrition can negatively affect the immune system. For this reason, adequate protein and energy intake should be provided to the patients. Also, overconsumption of saturated fat, sugar, and refined carbohydrates can both negatively affect the immune system and trigger chronic diseases in transplantation patients. In addition, vitamins and minerals should be monitored and inadequacy should be prevented due to immunomodulatory effects. Applying nutritional therapy suitable for the symptoms of renal transplantation patients and preventing comorbidities may reduce the risk and severity of COVID-19 infection.