Epidemiology of Dialysis Patients and Heart Failure Patients
Section snippets
The Concept of Reverse Epidemiology or Risk Factor Paradox
In highly industrialized, affluent nations, undernutrition is an uncommon cause of poor outcome in the general population, instead overnutrition is associated with a greater risk for cardiovascular disease and has an immense epidemiologic impact on the burden of cardiovascular disease and on shortened survival. In contrast, in dialysis patients in the same affluent countries, undernutrition appears to be one of the most common risk factors for adverse cardiovascular events and death.18, 19, 20,
Other Populations With Reverse Epidemiology
The reverse epidemiology is not unique to the dialysis population.7 Patients with CHF,26, 27 geriatric populations,28, 29 hospitalized patients,30 patients with malignancy,31 those living with acquired immune deficiency syndrome,32 and possibly other vulnerable populations such as those with chronic obstructive pulmonary disease33 also show similar paradoxes.18 Indeed, even chronic tobacco consumption may change the association between obesity and mortality.34 Hence, there appears to be at
Malnutrition-Inflammation-Cachexia Syndrome
Dialysis patients not only have a high prevalence of malnutrition but also a higher occurrence rate of inflammation, as evidenced by increased biomarkers such as C-reactive protein (CRP) and proinflammatory cytokines.35, 36, 37, 38, 39, 40 Both malnutrition and inflammation are associated strongly with each other and with many nutritional measures in the same direction. As yet, the relative contributions of measures of these 2 conditions to each other and to outcomes in dialysis patients are
Is Inflammation the Answer?
In the general population, indicators of inflammation, including increased serum CRP level, are stronger predictors of cardiovascular events than low-density lipoprotein (LDL) hypercholesterolemia.63, 64 Several studies have indicated a strong association between inflammatory markers including serum CRP level and proinflammatory cytokines such as tumor necrosis factor, interleukin-6, and interleukin-8 and prospective mortality in dialysis patients61, 65, 66, 67 and CHF patients.68 Hence, at
Short-Term Versus Long-Term Survival
In contrast to the conventional cardiovascular risk factors and overnutrition that require several years to decades to exert their deleterious effect, the impact of MICS and undernutrition is fast to ensue with decreased survival within a much shorter period of time. This time discrepancy hypothesis is a plausible explanation for the reverse epidemiology observed in vulnerable populations, in whom the undernutrition overwhelms the presence of overnutrition, leading to poor short-term survival
Evidence For and Against Reverse Epidemiology
In the following sections, we review the most recent literature on the atypical epidemiology of the dialysis and CHF patient population as they pertain to the association between conventional risk factors and clinical outcomes including mortality (see Table 2).
Clinical Relevance of the Concept of Reverse Epidemiology
The forgoing studies have contributed to the growing confusion and have left physicians with a dilemma as to whether to treat obesity, hypercholesterolemia, and hypertension in dialysis and heart failure patients. Treatment of hyperhomocysteinemia with folic acid in dialysis patients has been questioned. It is not clear whether dietary calcium intake should be restricted or whether intravenous iron mitigates or worsens the death risk in dialysis patients. The wisdom of recommending weight loss
Racial Disparity and Reverse Epidemiology
Underlying disparities in access to health care, income, education, diet, lifestyle, and comorbid conditions have been implicated as the reason why black individuals have higher total mortality rates than whites.210, 211, 212 In sharp contrast, black dialysis patients have a much lower annual mortality rate (18%) than whites (28%).1 Dialysis patients of different races also have different quality-of-life scores.213, 214 Studying racial disparities in the context of reverse epidemiology may
Obesity in Kidney Allograft Recipients
The prevalence of obesity has been growing in CKD patients being evaluated for transplantation.236 A recent study by Friedman et al237 reported 25% of kidney transplant recipients were obese in 2000 to 2001, an increase in prevalence by 116% when compared with 1987 to 1989. Most observational studies have shown higher rates of mortality among obese renal allograft recipients.236, 238, 239, 240, 241, 242, 243, 244 Because obesity and morbid obesity confer survival advantages in MHD patients, and
Future Trends and Steps
The poor clinical outcomes in dialysis patients do not seem to be amenable to interventions that target the traditional cardiovascular risk factors. If our hypothesis is true that a complex set of conditions that are related to malnutrition and inflammation, called MICS, is the cause of this risk factor reversal and high death rate and if the short-term death risk caused by undernutrition overwhelms the long-term effects of overnutrition, then the key to improving survival in dialysis and heart
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2021, Current Problems in CardiologyCitation Excerpt :Heart failure incidence is rising due to the increasing age of the population as well as improved diagnostic techniques for the detection of heart failure.1-4 Improved treatment and survival of patients with ischemic heart disease have also increased the incidence of heart failure.3,4 Ischemic heart disease is the most common cause of heart failure.
Is it Important to Prevent and Treat Protein-Energy Wasting in Chronic Kidney Disease and Chronic Dialysis Patients?
2018, Journal of Renal NutritionCitation Excerpt :More research would seem helpful to examine the influence of different combinations of these 3 conditions on the patient's outcome. Although PEW is strongly associated with adverse outcomes in advanced CKD and ESKD patients,49-54 some authorities suggest that the association of PEW with adverse outcomes generally occurs only when inflammatory processes or comorbid conditions are also present; hence, there may be only a weak causal association or no association of PEW with increased morbidity and mortality in the absence of associated inflammatory conditions.59 According to this perception, the relation between PEW and adverse clinical events in these individuals may be due to the presence of underlying morbid or inflammatory processes that both cause PEW and independently increase morbidity and mortality and particularly cardiovascular or atherosclerotic morbidity.61
Changing the paradigms for the treatment of chronic kidney disease
2017, Kidney International SupplementsDevelopment and validation of cardiovascular risk scores for haemodialysis patients
2016, International Journal of CardiologyAltered sleep structure in patients with end-stage renal disease
2016, Sleep MedicineCitation Excerpt :The present study shows that ESRD patients slept, on average, for only 4.6 hours, which can be considered sleep deprivation. Since the main cause of mortality among patients with ESRD is cardiovascular disease [23], sleep deprivation might be an important contributing factor. Poor sleep quality and SA are associated with reduced quality of life, cognitive impairment, and higher mortality among ESRD patients on dialysis [7–9,24,25].