Characterizing dietary intake and physical activity affecting weight gain in kidney transplant recipients

Investigation of Weight Gain and Affecting Factors in Kidney Transplant Recipients in the First 2 Years After Transplant

OBJECTIVES

It is necessary to examine weight gain and affecting factors after kidney transplant. This study was performed to examine weight gain and affecting factors in kidney transplant recipients in the first 2 years after transplant.

MATERIALS AND METHODS

This descriptive cross-sectional study included 139 kidney transplant recipients who were regularly followed by 2 university hospitals in the first 2 years after transplant. Data were collected with the use of a sociodemographic and clinical features' form and the General Self-Efficacy Scale. Weight and body mass index at 3, 6, 12, and 24 months after transplant were evaluated. Differences between weight (in kilograms) and body mass index (in kilograms divided by height in meters squared) at the first outpatient clinic visit and weight and body mass index at 24 months after transplant were calculated.

RESULTS

The mean age of patients was 46.32 ± 12.39 years. Differences in mean weight and body mass index between the first posttransplant outpatient clinic visit and at month 24 posttransplant were 7.07 ± 7.57 and 2.6 ± 2.37, respectively. Statistically significant differences were found in weight and body mass index at 2 years posttransplant. As age increased, weight gain decreased. Differences in weight gain and body mass index were not significantly associated with sex, presence of chronic diseases, donor type, steroid dose, and self-efficacy.

CONCLUSIONS

Kidney transplant recipients in our study population had increased weight and body mass index at 2 years after transplant. Younger kidney transplant recipients had higher weight gains. Therefore, kidney transplant recipients, especially younger ones, should be closely followed in terms of weight gain after transplant.

Weight Gain After Heart Transplantation in Adults: Systematic Review and Meta-Analysis

Gain in weight is common after heart transplantation but the magnitude of usual weight gain and whether this varies by country is unknown. We systematically reviewed all relevant studies to quantify weight change among heart transplant recipients (HTRs) in the years after transplantation and assess variation with geographic location. We searched PubMed, Cumulative Index to Nursing and Allied Health Literature, and Excerpta Medica Database databases to September 2020. Eligible studies reported adult HTRs' mean/median weight and/or body mass index (BMI) up to time of transplantation (baseline) and posttransplantation in any language. Weighted mean differences (WMDs) (95% confidence intervals [CIs]) of weight/BMI from baseline to posttransplantation were estimated using a random-effects model. Ten studies met the inclusion criteria. Pooled analysis showed weight gain of 7.1 kg (95% CI, 4.4-9.8 kg) in HTRs 12 months posttransplant, with corresponding BMI increase of 1.69 kg/m2 (95% CI, 0.83-2.55 kg/m2). Greatest weight gain at 12 months posttransplant occurred in US HTRs (WMD weight 10.42 kg, BMI 3.25 kg/m2) and least, in European HTRs (WMD weight 3.10 kg, BMI 0.78 kg/m2). In conclusion, HTRs gain substantial weight in the years after transplantation, but varying widely by geographic location.

Feasibility and acceptability of a televideo physical activity and nutrition program for recent kidney transplant recipients

Background

Post-transplant weight gain affects 50-90% of kidney transplant recipients adversely affecting survival, quality of life, and risk for diabetes and cardiovascular disease. Diet modification and physical activity may help prevent post-transplant weight gain. Methods for effective implementation of these lifestyle modifications are needed. The objective of this study is to assess the feasibility and acceptability of a remotely delivered nutrition and physical activity intervention among kidney transplant recipients. Secondary aims were to estimate the effectiveness of the intervention in producing changes in physical activity, qualify of life, fruit and vegetable intake, and consumption of whole grains and water from baseline to 6 months.

Methods

A randomized controlled study for stable kidney transplant recipients between 6 and 12 months post-transplantation was conducted. Participants were randomly assigned 1:1 to a technology-based, lifestyle modification program (intervention) or to enhanced usual care (control).

Results

The first 10 kidney transplant recipients screened were eligible and randomized into the intervention and control groups with no significant between-group differences at baseline. Health coaching attendance (78%) and adherence to reporting healthy behaviors (86%) were high. All participants returned for final assessments. The weight in controls remained stable, while the intervention arm showed weight gain at 3 and 6 months. Improvements were found for physical activity, quality of life, and fruit and vegetable intake in both groups. All participants would recommend the program to other transplant recipients.

Conclusions

Our data suggest that a remotely delivered televideo nutrition and physical activity intervention is feasible and valued by patients. These findings will aid in the development of a larger, more prescriptive, randomized trial to address weight gain prevention.

Trial registration

Clinicaltrials.gov Identifier NCT03697317. Retrospectively registered on October 5, 2018.

Weight Gain, Energy Intake, Energy Expenditure, and Immunosuppressive Therapy in Kidney Transplant Recipients

BACKGROUND

Weight gain after kidney transplantation is a common health problem. The factors in weight gain after kidney transplant include many factors such as age, ethnicity, gender, change in lifestyle (eg, kilocalorie intake and physical activity level), and immunosuppressive therapy.

RESEARCH QUESTIONS

This study aimed to evaluate the relationship between weight gain and energy intake in dietary, energy expenditure in physical activity, and immunosuppressive therapy in kidney transplant recipients.

DESIGN

This prospective, observational study included 51 participants who underwent kidney transplant, during 6 months from the start of the study. Anthropometric measurements were performed at first week, third- and sixth-month follow-ups of transplant recipients. Participants also completed 3-day "Dietary Record Form" and the "Physical Activity Record Form" at each follow-up. Simple frequency, analysis of variance analysis, and correlation analysis were used for data analysis.

RESULTS

Weight gain in sixth month follow-up compared to baseline value was positively related to energy intake in first week (r = 0.59), third month (r = 0.75), and sixth month (r = 0.67) follow-ups, and energy expenditure in first week (r = 0.35) and sixth month (r = 0.34) follow-ups. However, weight gain was negatively related to mycophenolate mofetil dose (mg/d) in sixth month (r = -0.31) follow-up (P < .05).

DISCUSSION

The results of this study provide an opportunity to reflect and discuss on modifiable risk factors such as energy intake and energy expenditure that affect weight gain posttransplantation in participants. It also examines the relationship between immunosuppressive therapy. Additionally, these results can be effective in designing interventions and managing risk factors to achieve weight management goals.

A Comparison of the Indirect Calorimetry and Different Energy Equations for the Determination of Resting Energy Expenditure of Patients With Renal Transplantation

OBJECTIVE

We aimed to evaluate the agreement between the resting energy expenditure (REE) obtained by indirect calorimetry and eight prediction equations in adult patients with renal transplantation and a newly developed REE prediction equation for use in patients with renal transplantation in the clinic.

METHODS

A total of 51 patients (30 males and 21 females) were involved in the study. The REE was measured by indirect calorimetry and compared with the previous prediction equations. The agreement was assessed by the interclass correlation coefficient and by Bland-Altman plot analysis.

RESULTS

No significant difference was found in terms of age and body mass index between the genders. Differences between the predicted and measured REEs were maximum in the Bernstein equation (-478 kcal) and minimum in the Cunningham equation (-69 kcal). It was found that underprediction values varied from 27.5% (chronic kidney disease equation) to 98.0% (Bernstein equation). The highest overprediction value was found in the Schofield equation (17.7%). The Cunningham equation and the new equation had the lowest root mean square error (265 kcal/day). In this study, fat-free mass (FFM) was found to be the most significant variable in multiple regression analysis (r²: 0.55). The new specific equation based on FFM was generated as 424.2 + 24.7∗FFM (kg). Besides that, it was found that the new equation and Cunningham equation were distributed randomly according to Bland-Altman analysis. A supplementary new equation based on available anthropometric measurements was developed as -1996.8 + 19.1∗height (cm) + 7.2∗body weight (kg).

CONCLUSION

This study showed that most of the predictive equations significantly underestimated REE. In patients with renal transplantation, if the REE is not measurable by indirect calorimetry, the use of the proposed equations will be more accurate.

Nutrition Trends in Kidney Transplant Recipients: the Importance of Dietary Monitoring and Need for Evidence-Based Recommendations

Many physiological properties of the renal system influence nutrient metabolism, elimination, and homeostasis. Kidney failure poses significant challenges to maintaining adequate nutrition, most of which transplantation ameliorates. Comprehensive recommendations for managing nutritional derangements for patients with chronic kidney disease and end stage renal disease exist; however, there are only sparse guidelines for post-transplant malnutrition and adverse outcomes. Not only are guidelines limited, but little is known about dietary trends of post-kidney transplant recipients. This review describes guidelines for prevalent metabolic and nutritional complications post-kidney transplantation and also evaluates changes in caloric intake and diet composition after transplantation. This topic is important because nutrition influences allograft function and a number of cardiovascular risk factors including blood pressure, dyslipidemia, weight, and diabetes. In addition, many dietary recommendations and modifiable lifestyle changes should be tailored for specific complications of transplant patients, namely immunosuppression side effects, dietary restrictions, and electrolyte imbalances.

Characterization of Body Composition and Fat Mass Distribution 1 Year After Kidney Transplantation

PURPOSE

In some recipients, significant weight gain occurs after kidney transplantation. Weight gain is associated with poor outcomes, particularly increased cardiovascular risk. In this study, we characterized changes in body mass index and body fat mass and compared them based on gender and race.

METHODS

Fifty-two kidney transplant recipients (aged ≥18 years old, 50% men, 58% African American) were enrolled into a prospective study. Body mass index and body fat mass were measured at baseline and 12 months posttransplant. Body fat mass was determined by dual-energy X-ray absorptiometry.

RESULTS

The mean increase in body weight was 3.7kg at 12 months; 36.5% (n=19) gained at least 10% of their baseline body weight. Body mass index, percentage of total body fat, and trunk fat were significantly increased. In subgroups, women and African American showed significant increases in body mass index and body fat measures. More participants were classified as obese based on total body fat compared to body mass index. Calories from fat were significantly increased at 12 months and associated with increased body mass index, total body fat, and trunk fat. Days of physical activity were significantly increased.

CONCLUSION

Both body mass index and total body fat mass were significantly increased at 12 months following kidney transplantation, especially for women and African Americans. Importantly, more participants were classified as obese based on total body fat compared to body mass index. Relevant nutrition and physical intervention should be provided, and both body mass index and body fat mass should be evaluated when monitoring weight gain.

A Prospective Study of Depression and Weight Change After Kidney Transplant

Context:

Kidney transplant recipients have great risk for gaining significant weight (upward of 10 kg) in the first year posttransplant. Clinical depression can occur in response to life situations and is associated with weight gain.

Objective:

To explore the association between demographic characteristics, weight change, and depression posttransplantation.

Design:

Secondary data analysis on longitudinal data collected for a larger observational study. Demographic characteristics, weight, and Center for Epidemiologic Studies Depression Scale (CES-D) data were obtained at baseline (BL) (time of transplantation), 6, and 12 months posttransplant. The CES-D scores were compared among time points using means, standard deviations, correlations, t tests, and chi-square as well as by multiple regression modeling.

Setting:

Regional transplant center in the mid-south United States.

Participants:

Forty-seven kidney transplant recipients (55% female, 57% African American, mean age 52.5 years). Weight change ranged from −18.1 to +24.8 kg.

Results:

In all, 62% reported baseline CES-D scores indicative of depression, with lower scores indicating less psychological distress at 6 and 12 months (47% and 49%, respectively). We found no significant differences among CES-D scores at any time point. Regression models found age, race, gender, and weight change to be predictive of CES-D scores at 6 months ( P = .04, R2 = .137). Age was the most influential ( P = .008), with older individuals more likely to obtain higher CES-D scores. Since the experience of depression is common at transplant and during the first year, it is important that transplant recipients be evaluated for depression early in the recovery period.

Oxidative stress is associated with weight gain in recipients at 12-months following kidney transplantation

OBJECTIVE

Weight gain after kidney transplantation (Tx) is considered a risk factor for poor outcomes. Increased oxidative stress is associated with not only chronic renal disease and Tx, but also obesity and cardiovascular disease. The aim of this pilot study was to test whether oxidative stress is related to weight gain at 12-months after kidney Tx and to obtain preliminary insight into potential mechanisms involved.

DESIGN & METHODS

Recipients (n=33) were classified into two groups; weight loss and weight gain, based on their weight changes at 12-months post-transplant. Total antioxidant capacity (TAOC) and lipid peroxidation (TBARS) were measured to evaluate oxidative stress from plasma at baseline and 12-months. A secondary data analysis was conducted to identify potential gene regulation.

RESULTS

Seventeen recipients lost (-6.63±5.52kg), and sixteen recipients gained weight (8.94±6.18kg). TAOC was significantly decreased at 12-months compared to baseline for the total group, however, there was no significant difference between groups at either time point. TBARS was higher in weight gain group, at both time points, and it was significantly higher at 12-months (p=0.012). Gene expression profiling analysis showed that 7 transcripts annotated to reactive oxygen species related genes in adipose tissue were expressed significantly lower in weight gain group at baseline, which might be a negative feedback mechanism to reduce oxidative stress.

CONCLUSION

These results may indicate that elevated oxidative stress (TBARS) is associated with weight gain after kidney Tx and that incorporating early clinical prevention strategies known to decrease oxidative stress could be recommended.

A Pilot Study of Demographic and Dopaminergic Genetic Contributions to Weight Change in Kidney Transplant Recipients

Kidney transplant recipients often experience a significant amount of weight gain in the first year post-transplantation. While demographic factors such as age, race, and sex have been associated with weight gain in this population, these factors do not explain all of the variability seen. A number of studies have suggested that genetics also plays a critical role in weight changes. Recently, alterations in the activity of the neurotransmitter dopamine have been associated with weight change, and gene expression studies in kidney transplant recipients have supported this association. The purpose of this pilot study is to first examine the feasibility and methodology, and then to examine the associations of age, race, sex, and genotype for 13 SNPs and 3 VNTRs in 9 dopaminergic pathway genes (ANKK1, DRD2, DRD3, DRD4, SLC6A3/DAT1, MAOA, MAOB, COMT, CPE) for associations with percent weight change at 12 months post-transplantation. Seventy kidney transplant recipients had demographic and clinical data collected as a part of a larger observational study. DNA was extracted from repository buffy coat samples taken at the time of transplant, and genotyped using Taqman and PCR based methods. Three SNPs were independently associated with percent weight change: ANKK1 rs1800497 (r = -0.28, p = 0.05), SLC6A3/DAT1 rs6347 (p = 0.046), and CPE rs1946816 (p = 0.028). Stepwise regression modelling confirmed the combined associations of age (p = 0.0021), DRD4 VNTR 4/5 genotype (p = 0.0074), and SLC6A3/DAT1 rs6347 CC genotype (p = 0.0009) and TT genotype (p = 0.0004) with percent weight change in a smaller sample (n = 35) of these kidney transplant recipients that had complete genotyping. These associations indicate that there may be a genetic, and an age component to weight changes post transplantation.

Obesity and organ transplantation: successes, failures, and opportunities

The increasing rate of societal obesity is also affecting the transplant world through obesity in candidates and donors as well as its posttransplant repercussions. Being overweight and obese has been shown to have significant effects on both short- and long-term complications as well as patient and graft survival. However, much of the comorbidity can be controlled or prevented with careful patient selection and aggressive management. A team approach to managing obesity and its comorbidities both pre- and posttransplant is essential for successful transplant outcomes. Complicating understanding the results of obesity research is the inclusion different weight categories, use of listing vs transplant weights, patient populations large enough for statistical power, and changes in transplant management, especially immunosuppression protocols, anti-infection protocols, and operative techniques. Much more research is needed regarding many elements, including safe weight loss before transplantation, prevention of weight gain after transplant, genomic influences, and the role of bariatric surgery in the transplant process.

Expression levels of obesity-related genes are associated with weight change in kidney transplant recipients

Background

The aim of this study was to investigate the association of gene expression profiles in subcutaneous adipose tissue with weight change in kidney transplant recipients and to gain insights into the underlying mechanisms of weight gain.

Methodology/Principal Findings

A secondary data analysis was done on a subgroup (n = 26) of existing clinical and gene expression data from a larger prospective longitudinal study examining factors contributing to weight gain in transplant recipients. Measurements taken included adipose tissue gene expression profiles at time of transplant, baseline and six-month weight, and demographic data. Using multivariate linear regression analysis controlled for race and gender, expression levels of 1553 genes were significantly (p<0.05) associated with weight change. Functional analysis using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes classifications identified metabolic pathways that were enriched in this dataset. Furthermore, GeneIndexer literature mining analysis identified a subset of genes that are highly associated with obesity in the literature and Ingenuity pathway analysis revealed several significant gene networks associated with metabolism and endocrine function. Polymorphisms in several of these genes have previously been linked to obesity.

Conclusions/Significance

We have successfully identified a set of molecular pathways that taken together may provide insights into the mechanisms of weight gain in kidney transplant recipients. Future work will be done to determine how these pathways may contribute to weight gain.