Prevalence of Metabolic Syndrome in Heart Transplant Patients: Role of Previous Cardiopathy and Years Since the Procedure—the TRACA Study

Update on Nutritional Advice Post-Heart Transplant: A Cross-Sectional Study across French-Speaking European Centers

INTRODUCTION

Heart transplantation is the standard treatment for severe heart failure. Graft preservation and infectious risk secondary to immunosuppressive drugs lead healthcare teams to offer nutritional advice to patients upon discharge from the hospital. However, no consensus or recommendation is available.

METHOD

We conducted a study to review the practices in all 26 centers providing heart transplantation in French-speaking Europe. We requested and analyzed the written documents these centers provided to their patients. The same two dieticians categorized the highlighted pieces of advice into distinct, autonomous categories.

RESULTS

We identified 116 pieces of advice, categorized into three areas: dietary restrictions for immunosuppressant/food interaction; environmental and food preparation guidelines and prevention of foodborne infections; and healthy and active lifestyle recommendations. Except for advice on immunosuppressant/food interaction, over one-third of the centers suggest discontinuing advice within 2 years post-transplant. General dietary advice covers lipids, carbohydrates, protein, calcium, sodium, and fiber but offers limited guidance on fatty acids despite their importance in cardiovascular risk prevention.

CONCLUSION

This study represents a pioneering exploration of the nutritional advice provided to patients following cardiac transplantation. It underscores the critical necessity of establishing consensus-based clinical guidelines in this domain.

Changes in nutritional status and the development of obesity and metabolic syndrome following pediatric heart transplantation

BACKGROUND

Nutritional status in pediatric patients undergoing heart transplantation (HT) is frequently a focus of clinical management and requires high resource utilization. Pre-operative nutrition status has been shown to affect post-operative mortality but no studies have been performed to assess how nutritional status may change and the risk of developing nutritional comorbidities long-term in the post-transplant period.

METHODS

A single-center retrospective chart review of patients ≥2 years of age who underwent heart transplantation between 1/1/2005 and 4/30/2020 was performed. Patient data were collected at listing, time of transplant, 1-year, and 3-year follow-up post-transplant. Nutrition status was classified based on body mass index (BMI) percentile in the primary analysis. Alternative nutritional indices, namely the nutrition risk index (NRI), prognostic nutrition index (PNI), and BMI z-score, were utilized in secondary analyses.

RESULTS

Of the 63 patients included, the proportion of patients with overweight/obese status increased from 21% at listing to 41% at 3-year follow-up. No underweight patients at listing became overweight/obese at follow-up. Of patients who were overweight/obese at listing, 88% maintained that status at 3-year follow-up. Overweight/obese status at listing, 1-year, and 3-year post-transplantation were significantly associated with developing metabolic syndrome. In comparison to the alternative nutritional indices, BMI percentile best predicted post-transplant metabolic syndrome.

CONCLUSIONS

The results suggest that pediatric patients who undergo heart transplantation are at risk of developing overweight/obesity and related nutritional sequelae (ie, metabolic syndrome). Improved surveillance and interventions targeted toward overweight/obese HT patients should be investigated to reduce the burden of associated comorbidities.

Metabolic Syndrome and Heart Transplantation: An Underestimated Risk Factor?

Metabolic Syndrome (MetS), a multifactorial condition that increases the risk of cardio-vascular events, is frequent in Heart-transplant (HTx) candidates and worsens with immunosuppressive therapy. The aim of the study was to analyze the impact of MetS on long-term outcome of HTx patients. Since 2007, 349 HTx patients were enrolled. MetS was diagnosed if patients met revised NCEP-ATP III criteria before HTx, at 1, 5 and 10 years of follow-up. MetS was present in 35% of patients pre-HTx and 47% at 1 year follow-up. Five-year survival in patients with both pre-HTx (65% vs. 78%, p < 0.01) and 1 year follow-up MetS (78% vs 89%, p < 0.01) was worst. At the univariate analysis, risk factors for mortality were pre-HTx MetS (HR 1.86, p < 0.01), hypertension (HR 2.46, p < 0.01), hypertriglyceridemia (HR 1.50, p=0.03), chronic renal failure (HR 2.95, p < 0.01), MetS and diabetes at 1 year follow-up (HR 2.00, p < 0.01; HR 2.02, p < 0.01, respectively). MetS at 1 year follow-up determined a higher risk to develop Coronary allograft vasculopathy at 5 and 10 year follow-up (25% vs 14% and 44% vs 25%, p < 0.01). MetS is an important risk factor for both mortality and morbidity post-HTx, suggesting the need for a strict monitoring of metabolic disorders with a careful nutritional follow-up in HTx patients.

Impact of Previous Conventional Cardiac Surgery on the Clinical Outcomes After Heart Transplantation

The impact of the type, purpose, and timing of prior surgery on heart transplantation (HT) remains unclear. This study investigated the influence of conventional cardiac surgery (PCCS) on HT outcomes. This study analyzed HTs performed between 1999 and 2019 at a single institution. Patients were categorized into two groups: those with and without PCCS. Short-term outcomes, including post-transplant complications and mortality rates, were evaluated. Cox proportional and Kaplan-Meier survival analyses were used to identify risk factors for mortality and assess long-term survival, respectively. Of 368 patients, 29% had PCCS. Patients with PCCS had a higher incidence of post-transplant complications. The in-hospital and 1 year mortality rates were higher in the PCCS group. PCCS and cardiopulmonary bypass time were significant risk factors for 1 year mortality (hazard ratios = 2.485 and 1.005, respectively). The long-term survival rates were lower in the PCCS group, particularly in the first year. In sub-analysis, patients with ischemic cardiomyopathy and PCCS had the poorest outcomes. The era of surgery and timing of PCCS in relation to HT did not significantly impact outcomes. In conclusion, PCCS worsen the HT outcomes, especially in patients with ischemic etiology. However, the timing of PCCS and era of HT did not significantly affect this concern.

Obesity and dyslipidemia predict cardiac allograft vasculopathy and graft loss in children and adolescents post-heart transplant: A PHTS multi-institutional analysis

BACKGROUND

Obesity and dyslipidemia afflict children of all ages. We explored the prevalence of obesity and dyslipidemia in pediatric heart transplant (HT) recipients and its effects on cardiac allograft vasculopathy (CAV) and survival.

METHODS

This study included primary HT recipients (≤18 years) transplanted between 01/1996 and 12/2018 included in the Pediatric Heart Transplant Society database. Obesity was categorized according to WHO/CDC guidelines and dyslipidemia according to the National Cholesterol Education Program. Kaplan-Meier analyses for CAV and graft loss stratified for BMI and lipid panels were generated and risk factors identified using multivariate analyses.

RESULTS

Among 6291 HT patients (median age [range] at HT = 4.3 [0.6-12.8] years; 45% Female; 68% White), 56% had a normal BMI at HT. Obese patients at HT had an increased risk for graft loss (HR 1.19, 95% CI 1.01-1.4, p = .04). Poor total cholesterol (TC), LDL-C, and TG were associated with the risk of both CAV (HR 1.79, p < .0001; HR 1.65, p = .0015; HR 1.53, p < .0001, respectively) and graft loss (HR 1.58, p = .0008; HR 1.22, p = .04; HR 1.43, p = .0007, respectively).

CONCLUSIONS

Pediatric patients who are obese at the time of HT and dyslipidemic at 1 year post-HT are at an increased risk for CAV and graft loss. Preventative interventions may reduce morbidity and mortality among this cohort.

New-onset Obesity After Lung Transplantation: Incidence, Risk Factors, and Clinical Outcomes

BACKGROUND

Lung transplant (LTx) recipients who gain weight after transplantation may experience an upward shift in body mass index (BMI) that places them in the obese category. The incidence, risk factors, and impact on metabolic health and mortality of new-onset obesity have not been documented in the LTx setting.

METHODS

This single-center retrospective study included 564 LTx recipients. Individuals were stratified according to their BMI trajectories from pretransplant evaluation up to 10 y posttransplant. New-onset obesity was defined as a pretransplant BMI <30 kg/m2 and posttransplant BMI >30 kg/m2. The incidence, risk factors, and posttransplant diabetes mellitus, metabolic syndrome, and mortality of recipients with new-onset obesity were compared with those of nonobese (BMI <30 kg/m2, pre/post-LTx), consistently obese (BMI >30 kg/m2, pre/post-LTx), and obese recipients with weight loss (BMI >30 kg/m2 pre-LTx, BMI <30 kg/m2 post-LTx).

RESULTS

We found that 14% of recipients developed obesity after transplantation. Overweight individuals (odds ratio [OR]: 9.01; 95% confidence interval [CI] [4.86-16.69]; P < 0.001) and candidates with chronic obstructive pulmonary disease (OR: 6.93; 95% CI [2.30-20.85]; P = 0.001) and other diagnoses (OR: 4.28; 95% CI [1.22-14.98]; P = 0.023) were at greater risk. Multivariable regression analysis showed that new-onset obesity was associated with a greater risk of metabolic syndrome (hazard ratio: 1.70; 95% CI [1.17-2.46]; P = 0.005), but not of posttransplant diabetes mellitus, than nonobesity. Recipients with new-onset obesity had a survival comparable to that of consistently obese individuals.

CONCLUSIONS

A greater understanding of the multifaceted nature of post-LTx obesity may lead to interventions that are better tailored to the characteristics of these individuals.

Cardiovascular health in pediatric heart transplant patients

BACKGROUND

Ideal "cardiovascular health" (CVH)-optimal diet, exercise, nonsmoking, BMI, BP, lipids, and glucose-is associated with healthy longevity in adults. Pediatric heart transplant (HT) patients may be at risk for suboptimal CVH.

METHODS

Single-center retrospective study of HT patients 2003-2014 who survived 1 year post-transplant. Five CVH metrics were collected at listing, 1, 3 and 5 years post-transplant (diet and exercise were unavailable). CVH was scored by summing individual metrics: ideal = 2, intermediate = 1, and poor = 0 points; total scores of 8-10 points were considered high (favorable). CVH was compared between HT patients and the US pediatric population (GP) utilizing NHANES 2007-2016. Logistic regression was performed to examine the association of CVH 1 year post-transplant with a composite adverse outcome (death, re-listing, coronary vasculopathy, or chronic kidney disease) 3 years post-transplant.

RESULTS

We included 110 HT patients (median age at HT: 6 years [range 0.1-21]) and 19,081 NHANES participants. CVH scores among HT patients were generally high at listing (75%), 1 (74%), 3 (87%) and 5 (76%) years post-transplant and similar to GP, but some metrics (e.g., glucose) were worse among HT patients. Among HT patients, CVH was poorer with older age and non-Caucasian race/ethnicity. Per 1-point higher CVH score, the demographic-adjusted OR for adverse outcomes was 0.95 (95% CI, 0.7-1.4).

CONCLUSIONS

HT patients had generally favorable CVH, but some metrics were unfavorable and CVH varied by age and race/ethnicity. No significant association was detected between CVH and adverse outcomes in this small sample, but study in a larger sample is warranted.

Metabolic Consequences of Solid Organ Transplantation

Metabolic complications affect over 50% of solid organ transplant recipients. These include posttransplant diabetes, nonalcoholic fatty liver disease, dyslipidemia, and obesity. Preexisting metabolic disease is further exacerbated with immunosuppression and posttransplant weight gain. Patients transition from a state of cachexia induced by end-organ disease to a pro-anabolic state after transplant due to weight gain, sedentary lifestyle, and suboptimal dietary habits in the setting of immunosuppression. Specific immunosuppressants have different metabolic effects, although all the foundation/maintenance immunosuppressants (calcineurin inhibitors, mTOR inhibitors) increase the risk of metabolic disease. In this comprehensive review, we summarize the emerging knowledge of the molecular pathogenesis of these different metabolic complications, and the potential genetic contribution (recipient +/- donor) to these conditions. These metabolic complications impact both graft and patient survival, particularly increasing the risk of cardiovascular and cancer-associated mortality. The current evidence for prevention and therapeutic management of posttransplant metabolic conditions is provided while highlighting gaps for future avenues in translational research.

Postoperative weight gain during the first year after kidney, liver, heart, and lung transplant: a prospective study

CONTEXT

Studies of all types of organ transplant recipients have suggested that weight gain, expressed as an increase in body mass index (BMI), after transplant is common.

OBJECTIVES

To describe weight gain during the first year after transplant and to determine risk factors associated with weight gain with particular attention to type of transplant.

DESIGN, SETTING, AND PARTICIPANTS

A prospective study of 502 consecutive organ transplant recipients (261 kidney, 73 liver, 29 heart, 139 lung) to identify patterns of BMI change. Measurements were made during regular outpatient clinical visits at 2, 6, and 12 months after transplant. Data were retrieved from patients' charts and correlated with maintenance corticosteroid doses.

RESULTS

Overall, mean BMI (SD; range) was 23.9 (4.5; 13.6-44.1) at 2 months and increased to 25.4 (4.0; 13.0-42.2) by the end of the first postoperative year. BMI levels organized by World Health Organization categories showed a trend toward overweight/obesity in kidney (53.4%), liver (51.5%), heart (51.7%), and lung (33.1%) patients by 12 months after transplant. BMI changed significantly (P= .05) for all organ types and between all assessment points, except in kidney recipients. Maintenance corticosteroid doses were not a predictor of BMI at 12 months after transplant for most patients.

CONCLUSIONS

Weight gain was common among patients undergoing kidney, liver, heart, and lung transplant; however, many showed BMI values close to normality at the end of the first year after transplant. In most cases, increased BMI levels were related to obesity before transplant and not to maintenance corticosteroid therapy.

High prevalence of exercise-induced heart failure with normal ejection fraction in post-heart transplant patients

AIM

Post-heart transplant patients are at increased risk of diastolic dysfunction. The aim of this study was to assess the prevalence of isolated only exercise-induced heart failure with normal ejection fraction (HFNEF) in heart transplant recipients.

METHODS AND RESULTS

To determine pulmonary capillary wedge pressure (PCWP) at rest and during exercise, 81 patients after orthotopic heart transplantation with normal left ventricular ejection fraction (LVEF) underwent exercise right heart catheterization with simultaneous exercise echocardiography. Based on PCWP values, the patients were divided into three groups. Twenty-one patients had no evidence of HFNEF (PCWP at rest < 15 mmHg, maximal PCWP during exercise < 25 mmHg, prevalence 26%). Forty-seven subjects were found to have only exercise-induced HFNEF (PCWP at rest < 15 mmHg, maximal PCWP during exercise ≥ 25 mmHg, prevalence 58%). Thirteen patients had HFNEF already at rest (PCWP ≥ 15 mmHg at rest, prevalence 16%). Of the noninvasive parameters obtained at rest, multivariate regression analysis identified LV mass index adjusted for allograft age to be an independent predictor of exercise-induced HFNEF.

CONCLUSIONS

In heart transplant recipients with normal LVEF, there is a high prevalence of exercise-induced HFNEF. LV mass index adjusted for allograft age is predictive of exercise-induced HFNEF.

Metabolic syndrome and its components after liver transplantation: incidence, prevalence, risk factors, and implications

Metabolic syndrome is defined as the mutual existence of obesity, impaired fasting glucose levels, insulin resistance, hypertension, and dyslipidemia. After liver transplantation, patients typically develop these disorders, and even though there has been minimal research focused on the chronic impact of this syndrome on post-liver transplant patients, studies point to an association with major vascular events and fibrosis. The aim of the current work is to review data on the incidence, prevalence, risk factors, and implications of metabolic syndrome and its components in patients who have undergone liver transplantation.

Transplant-associated hyperglycemia

As patient survival after solid organ transplantation continues to improve, comorbidites associated with chronic hyperglycemia will assume increasing importance in limiting outcomes and quality of life. New-onset diabetes mellitus commonly occurs in the posttransplant setting and is associated with multiple complications including graft loss, cardiovascular disease, infection, and death. Furthermore, recent studies have begun to highlight the very high posttransplant prevalence and the significant cardiovascular implications of the prediabetic states of impaired fasting glucose and impaired glucose tolerance, indicating that the overall burden of transplantation-associated hyperglycemia is far greater than previously appreciated. Shared and distinct pathogenic factors and clinical repercussions exist among the organ-specific transplant scenarios. Diabetogenic immunosuppressive agents are common to all organ transplant settings, whereas glucose regulation is also strained by the restoration of failed hepatic and renal function. The atherogenic properties of hyperglycemia are particularly significant in the kidney transplant population, which has a marked predisposition to cardiovascular disease, whereas accelerated cardiac allograft vasculopathy and liver fibrosis have been associated with hyperglycemia in the heart and liver transplant settings, respectively. Aggressive screening will effectively detect transplant-associated hyperglycemia, whereas risk factor modification, lifestyle intervention and, where appropriate, drug therapy, may decrease its impact. Topics of future investigation should include the use of emerging diabetes therapies and avenues for the prevention and reversal of transplant-associated hyperglycemia.

High prevalence of metabolic syndrome after allogeneic hematopoietic cell transplantation

We conducted a cross-sectional study to estimate the prevalence of metabolic syndrome, a clustering of risk factors associated with cardiovascular disease, among 86 adults who had allogeneic hematopoietic-cell transplant (HCT) as compared with 258 age- and gender-matched US population controls selected from the 2005-2006 National Health and Nutrition Examination Survey database. The median age at study enrollment was 50 years (range, 21-71), and patients were at a median of 3 years (range, 1-21) from HCT. The prevalence of metabolic syndrome was 49% (95% confidence intervals (CI), 38-60%) among HCT recipients, a 2.2-fold (95% CI, 1.3-3.6, P=0.002) increase compared with controls. The prevalence rates of elevated blood pressure and hypertriglyceridemia were significantly higher among HCT recipients than among controls, but the prevalence rates of abdominal obesity, elevated blood glucose and low high-density lipoprotein cholesterol were not. HCT survivors with metabolic syndrome were more likely to have microalbuminuria (43 vs 10%) and elevated creatinine (31 vs 11%). No patient, donor or transplant characteristics were associated with the diagnosis of metabolic syndrome. We conclude that metabolic syndrome occurs frequently among allogeneic HCT survivors who are seen by transplant physicians. Approaches to screening, prevention and management of metabolic syndrome should be developed for HCT recipients.

[Nutritional analysis of 25 heart transplanted patients]

BACKGROUND AND OBJECTIVE

Malnutrition could be very important in patients under surgery. Moreover, the immunosuppressive therapy can cause metabolic and nutritional disorders to the transplanted patients. The aim of this study was to obtain information about the nutritional situation of the cardiac transplanted patients with biochemical and anthropometric parameters.

PATIENTS AND METHOD

A retrospective descriptive transversal study. We reviewed clinic records of cardiac transplanted patients between 2004 and 2005. Biochemical and anthropometric parameters recorded before surgery, in the intensive care unit and at the hospital discharge.

RESULTS

At discharge, there is a decrease of the following parameters: albumin, 68%; creatinine, 68%; proteins, 92%, and body mass index, 64%; whereas one year after discharge an increase of the body mass index was observed (60%). It was observed that 36% of the patients presented high results of triglycerides, after both a month and a year after discharge. The percentage is of 32% of glucose and between 52% and 24% for cholesterol, respectively.

CONCLUSIONS

In patients submitted to cardiac transplantation, there is a tendency for a damaged nutritional situation, both at discharge and after a year. It is important to point out the need for a nutritional education to decrease possible complications.

Systemic inflammation and metabolic syndrome in cardiac allograft vasculopathy

BACKGROUND

Metabolic syndrome and elevation of inflammatory markers is common in transplant recipients. We investigated the role of insulin resistance and C-reactive protein (CRP) in predicting development of angiographic cardiac allograft vasculopathy (CAV).

METHODS

CRP and lipid profile were measured in 114 cardiac transplant recipients at 4.7 +/- 3.1 years post-transplant. A triglyceride/high-density lipoprotein cholesterol (TG/HDL) ratio of >or=3 was considered a marker of insulin resistance. Ninety-seven patients (mean age +/- SD: 48.2 +/- 16.7 years) subsequently underwent routine coronary angiography at 8.6 +/- 3.2 years post-transplantation. Diagnosis of CAV required the presence of stenosis of >or=40% in any major branch, and/or distal pruning of secondary side branches. Coronary artery stenosis >or=70% was defined as severe.

RESULTS

Eighty-one percent of patients were treated with statins. Low-density lipoprotein (LDL)-cholesterol level was 98 +/- 26 mg/dl at study entry. CRP and TG/HDL were found to be predictors of development of CAV. CAV severity correlated with TG/HDL (p < 0.005), but not with CRP level. Freedom from CAV 5 years after study entry was 9% in patients with TG/HDL >3, CRP >3 mg/liter, as compared with 65% in patients with TG/HDL <3, CRP <3 mg/liter (p = 0.003). The combination of CRP >3 mg/liter and TG/HDL >3 identified a sub-group of patients having a 2.8-fold increased odds ratio for a combined end-point of cardiovascular (CV) events (percutaneous coronary intervention, coronary artery bypass graft, left ventricular ejection fraction <45%) and death (95% confidence interval 0.90 to 8.45, p = 0.07) compared to patients with CRP <3 mg/liter and TG/HDL <3.

CONCLUSIONS

CRP >3 mg/liter and TG/HDL >3 are cumulative risk factors for angiographic CAV and the combined end-point of CV events and death in transplant patients and these patients should be targeted for intervention.