n-3 polyunsaturated fatty acids, lipids and lipoproteins in end-stage renal disease

Disorders of serum omega-3 fatty acid composition in dialyzed patients, and their associations with fat mass

Patients with chronic kidney disease (CKD) are at increased risk of cardiovascular mortality. Lipid disorders, a constant feature of CKD, might contribute to this state. The aim of this study was to evaluate n-3 polyunsaturated fatty acids (PUFA) composition in CKD patients treated with dialysis, in comparison to the general population and to assess possible associations between the n-3 PUFA profile and anthropometric variables. Thirty-three prevalent dialysis patients were studied and compared with an age- and sex-adjusted control group of 22 patients. Fatty acid composition in serum was analyzed by gas chromatography with a mass spectrometer detector (GC-MS) and anthropometric measures were assessed by bioimpedance spectroscopy. The fatty acid profile of dialyzed patients was characterized by a significantly lower percentage content of n-3 PUFA. For α-linolenic acid (ALA), it was 0.21 ± 0.09% in dialysis patients versus 0.33 ± 0.11% in the control group (p < .001). For eicosapentanoic acid (EPA), 0.59 ± 0.23% versus 1.15 ± 0.87% (p < .001), and for docosahexaenoic acid (DHA) 1.11 ± 0.50% versus 1.75 ± 0.87% (p < .001), respectively. The amount of n-3 PUFA decreased with time on dialysis and it correlated positively with body fat mass. For DHA, this correlation was r = .48 (p < .01) and for EPA r = .40 (p < .05). Patients with CKD have a relatively low content of n-3 PUFA which may contribute to their high cardiovascular risk. Patients with a higher content of body fat are characterized by a favorable fatty acid composition.

Stirring the Pot: Can Dietary Modification Alleviate the Burden of CKD?

Diet is one of the largest modifiable risk factors for chronic kidney disease (CKD)-related death and disability. CKD is largely a progressive disease; however, it is increasingly appreciated that hallmarks of chronic kidney disease such as albuminuria can regress over time. The factors driving albuminuria resolution remain elusive. Since albuminuria is a strong risk factor for GFR loss, modifiable lifestyle factors that lead to an improvement in albuminuria would likely reduce the burden of CKD in high-risk individuals, such as patients with diabetes. Dietary therapy such as protein and sodium restriction has historically been used in the management of CKD. Evidence is emerging to indicate that other nutrients may influence kidney health, either through metabolic or haemodynamic pathways or via the modification of gut homeostasis. This review focuses on the role of diet in the pathogenesis and progression of CKD and discusses the latest findings related to the mechanisms of diet-induced kidney disease. It is possible that optimizing diet quality or restricting dietary intake could be harnessed as an adjunct therapy for CKD prevention or progression in susceptible individuals, thereby reducing the burden of CKD.

[Chronic kidney disease and dyslipidaemia]

Chronic kidney disease (CKD) has to be considered as a high, or even very high risk cardiovascular risk condition, since it leads to an increase in cardiovascular mortality that continues to increase as the disease progresses. An early diagnosis of CKD is required, together with an adequate identification of the risk factors, in order to slow down its progression to more severe states, prevent complications, and to delay, whenever possible, the need for renal replacement therapy. Dyslipidaemia is a factor of the progression of CKD that increases the risk in developing atherosclerosis and its complications. Its proper control contributes to reducing the elevated cardiovascular morbidity and mortality presented by these patients. In this review, an assessment is made of the lipid-lowering therapeutic measures required to achieve to recommended objectives, by adjusting the treatment to the progression of the disease and to the characteristics of the patient. In CKD, it seems that an early and intensive intervention of the dyslipidaemia is a priority before there is a significant decrease in kidney function. Treatment with statins has been shown to be safe and effective in decreasing LDL-Cholesterol, and in the reduction of cardiovascular events in individuals with CKD, or after renal transplant, although there is less evidence in the case of dialysed patients.

Food for thought: dietary changes in essential fatty acid ratios and the increase in autism spectrum disorders

The last decades have shown a spectacular and partially unexplained rise in the prevalence of autism spectrum disorders (ASD). This rise in ASD seems to parallel changes in the dietary composition of fatty acids. This change is marked by the replacement of cholesterol by omega-6 (n-6) fatty acids in many of our food products, resulting in a drastically increased ratio of omega-6/omega-3 (n-6/n-3). In this context, we review the available knowledge on the putative role of fatty acids in neurodevelopment and describe how disturbances in n-6/n-3 ratios may contribute to the emergence of ASDs. Both clinical and experimental research is discussed. We argue that a change in the ratio of n-6/n-3, especially during early life, may induce developmental changes in brain connectivity, synaptogenesis, cognition and behavior that are directly related to ASD.