A randomized controlled trial of exercise training on cardiovascular and autonomic function among renal transplant recipients

Physical activity interventions in adult kidney transplant recipients: an updated systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Kidney transplant recipients (KTRs) exhibit a high prevalence of cardiovascular disease (CVD) and adverse changes in physical fitness and body composition. Post-transplant management recommends being physically active and evidence in this field is growing. The aim of this review was to update our previous systematic review and meta-analysis of randomized controlled trials (RCTs) assessing the effects of physical activity and exercise training interventions in KTRs.

METHODS

A comprehensive literature search between March 2021 and September 2024 identified seven additional RCTs. Therefore, this updated review and meta-analysis includes 23 RCTs. Outcomes included cardiorespiratory fitness (CRF), strength, blood pressure, body composition, heart rate, markers of dyslipidemia and kidney function, and health-related quality of life.

RESULTS

Twenty-three RCTs, including 1,139 KTRs, were included. The median intervention length was 12 weeks with participants exercising between 2 and 7×/week. Most studies used a mixture of aerobic and resistance training but reporting and intervention content was highly varied. Significant improvements were observed in CRF (V̇O2peak; +3.87 mL/kg/min, p = .0004), physical function (sit-to-stand-60; +7.72 repetitions, p = .0001), and high-density lipoprotein (HDL; +0.13 mmol/L, p = .02). Isolated studies reported improvements in strength, bone health, lean mass, and quality of life (QoL). All studies were found to have a high or moderate risk of bias.

CONCLUSIONS

Exercise training or increasing physical activity may confer several benefits in adult KTRs, especially through the improvements in CRF and HDL which have been linked to CVD risk. Despite new literature, there is still a need for long-term larger sampled RCTs and more detailed reporting of intervention details and program adherence.

Diabetic kidney disease and cardiac autonomic neuropathy: insights on exercise rehabilitation

Patients with Diabetic Kidney Disease (DKD) suffer from various complications of diabetes mellitus, including autonomic neuropathy. Cardiac autonomic nervous system dysfunction is a common disorder in patients with diabetes mellitus and Chronic Kidney Disease (CKD), and is associated with an increased risk of arrhythmias and cardiovascular morbidity and mortality. Although the effects of exercise training have been thoroughly studied in different patient populations with CKD or diabetes mellitus, few studies have investigated the effects of exercise on cardiac autonomic nervous system activity in patients with DKD. This narrative review aims to summarize the evidence regarding the effects of exercise training on cardiac autonomic nervous system modulation in DKD patients.

Systematic review and meta-analysis of the efficacy of exercise intervention in kidney transplant recipients

BACKGROUND AND OBJECTIVE

There is uncertainty about the beneficial effects of exercise intervention for kidney transplant recipients. The purpose of our meta-analysis is to estimate the efficacy of exercise intervention in kidney transplant recipients.

METHODS

A database search according to the PICOS framework was performed for all published randomized, double-blind, placebo-controlled trials (RCTs) about exercise intervention for kidney transplant recipients. The databases involved include PubMed, Embase, and Cochrane Library.

RESULTS

A total of 16 RCTs (involving 827 patients) in compliance with inclusion criteria were included in our study. The results demonstrated that adequate exercise intervention improved statistically in creatinine clearance [mean difference (MD) =  - 0.29, 95% confidence interval (CI) - 0.46 to - 0.11, p = 0.001], serum urea (MD = - 21.57, 95% CI - 35.84 to - 7.29, p = 0.003), VO2 peak (MD = 3.20, 95% CI 1.97-4.43, p < 0.00001), high-density lipoprotein-cholesterol (HDL-C) (MD = 0.21, 95% CI 0.04-0.37, p = 0.01), 60-s sit to stand test (60-STS) (MD = 14.47, 95% CI 8.89-20.04, p < 0.00001), 6-min walk distance (6-MWD) (MD = 91.87, 95% CI 38.34-145.39, p = 0.0008), and 6-min walk test (6-MWT) (MD = 44.08, 95% CI 20.30-67.87, p = 0.0003) of patients after kidney transplantation. No between-groups differences (p > 0.05) were observed for anthropometric characteristics, body composition, serum cytokine levels, and quality of life short form-36 questionnaire (SF-36).

CONCLUSIONS

In kidney transplant recipients, appropriate exercise intervention improved renal function, cardiopulmonary function, physical performance.

TRIAL REGISTRATION

The PROSPERO registration number is CRD42022357574.

A High intensity Interval training (running and swimming) and resistance training intervention on heart rate variability and the selected biochemical factors in boys with type 1 diabetes

OBJECTIVE

The purpose of this research is to investigate the effect of High Intensity Interval Training and Resistance training (HIITR) on heart rate variability (HRV), blood glucose, and plasma biomarkers levels in adolescents with type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS

24 boys with T1D (FBS: 274.66 ± 52.99, age: 15.2 ± 1.78 years, and BMI = 19.61 ± 1.11) and 12 healthy boys (FBS: 92.75 ± 5.22, age: 15.08 ± 1.67 years, and BMI = 20.26 ± 2.66) were divided into three groups: Diabetes Training (DT, n = 12), Diabetes Control (DC, n = 12), and Healthy Control (HC, n = 12). HRV (24 h) was computed in time and frequency domains, anthropometric, biochemical parameters at rest, and aerobic capacity (VO2peak) obtained during a graded exercise testing (GXT). All variables were evaluated at the baseline and following 12 weeks of exercise training, done 3 days weekly. The statistical method used for data analysis was analysis of covariance (ANCOVA) test.

RESULTS

HRV, Hemoglobin A1c (HbA1c) and Fasting blood sugar (FBS), VO2peak, norepinephrine (NEP), and HDL-C indicated significant differences between both T1D groups compared to HC at baseline (p < 0.001). BMI, LDL-C, TC, and TG parameters were similar in all groups. HRV parameters, VO2peak and HDL-C, and NEP were significantly improved by exercise training, and HbA1c and FBS levels were significantly reduced (p < 0.001). There is a negative and significant correlation between LF/HF Ratio Difference (post-test minus pre-test) and VO2Peak Difference variables (post-test minus pre-test) (p < 0.001).

CONCLUSIONS

The present study suggests the importance of early screening for CVD risk factors in adolescent males with T1D. Also, it was revealed HIITR training compared to other training patterns, and cardiovascular health improves via enhancement of autonomic modulation, VO2peak, plasma lipids, and catecholamine levels.

Home-Based Exercise Training and Cardiac Autonomic Neuropathy in Kidney Transplant Recipients with Type-II Diabetes Mellitus

This randomized clinical trial aimed to examine the effects of a 6-month home-based, combined exercise training program on Cardiac Autonomic Neuropathy (CAN) in kidney transplant recipients (KTRs) with diabetes. Twenty-five KTRs (19 men (76.0%), with a mean age of 54.4 ± 11.3 years old, CAN and type II Diabetes Mellitus (DM-II)), were randomly assigned into two groups: A (n1 = 13 KTRs), who underwent a home-based exercise training program for 6 months, and B (n2 = 12 KTRs), who were assessed at the end of the study. A cardiopulmonary exercise testing (CPET), sit-to-stand test in 30 s (30-s STS), isokinetic muscle strength dynamometry, and 24-h electrocardiographic monitoring were applied to all participants, both at the baseline and at the end of the clinical trial. At first, there were no statistically significant differences between groups. After 6 months, group A showed higher values in exercise time by 8.7% (p = 0.02), VO2peak by 7.3% (p < 0.05), 30-s STS by 12.0% (p < 0.05), upper limb strength by 46.1% (p < 0.05), and lower limb strength by 24.6% (p = 0.02), respectively, compared to the B group. Furthermore, inter-group changes at the end of the 6-month study indicated that group A statistically increased the standard deviation of R-R intervals (SDNN) by 30.3% (p = 0.01), root mean square of successive differences between normal heartbeats (rMSSD) by 32.0% (p = 0.03), number of pairs of successive NN (R-R) intervals that differ by more than 50 ms (pNN50) by 29.0% (p = 0.04), high frequency (HF (ms2)) by 21.6% (p < 0.05), HF (n.u.) by 48.5% (p = 0.01), and turbulence slope (TS) by 22.5% (p = 0.02), and decreased the low frequency (LF (ms2)) by 13.2% (p = 0.01), LF (n.u.) by 24.9% (p = 0.04), and LF/HF ratio by 24% (p = 0.01), compared to group B. Linear regression analysis after the 6-month study showed that there was a strong positive correlation between VO2peak and SDNN (r = 0.701, p < 0.05) in group A. Moreover, multiple regression analysis showed that KTRs' participation in the exercise program showed favorable modifications to sympathovagal balance and aerobic capacity, as measured with SDNN and VO2peak, respectively. To summarize, diabetic KTRs' cardiac autonomic function and functional capacity can be improved after a home-based long-term exercise training program.

Cardiopulmonary exercise testing in patients with end-stage kidney disease: principles, methodology and clinical applications of the optimal tool for exercise tolerance evaluation

Chronic kidney disease (CKD), especially end-stage kidney disease (ESKD), is associated with an increased risk for cardiovascular events and all-cause mortality. Exercise intolerance as well as reduced cardiovascular reserve is extremely common in patients with CKD. Cardiopulmonary exercise testing (CPET) is a non-invasive, dynamic technique that provides an integrative evaluation of cardiovascular, pulmonary, neuropsychological and metabolic function during maximal or submaximal exercise, allowing the evaluation of functional reserves of these systems. This assessment is based on the principle that system failure typically occurs when the system is under stress and thus CPET is currently considered to be the gold standard for identifying exercise limitation and differentiating its causes. It has been widely used in several medical fields for risk stratification, clinical evaluation and other applications, but its use in everyday practice for CKD patients is scarce. This article describes the basic principles and methodology of CPET and provides an overview of important studies that utilized CPET in patients with ESKD, in an effort to increase awareness of CPET capabilities among practicing nephrologists.

Effects of a Combined Intradialytic Exercise Training Program and Music on Cardiac Autonomic Nervous System Activity in Hemodialysis Patients

This study aimed to examine the effect of an intradialytic exercise program in combination with music on heart rate variability (HRV) indices and functional capacity in patients on maintenance hemodialysis (HD). Methods: Forty HD patients were randomized to four training groups for six months: the combined music and exercise group (Group A), the exercise group (Group B), the music group (Group C), and the control group (Group D). At baseline and after 6 months, all participants underwent both short- (for 30 min) and long- (for 24 h) term measurements of HRV and functional capacity assessment with a 6 min walking test (6MWT). Patients of groups A and C listened to preferred music. Results: Long-term HRV analysis showed that standard deviation of all normal-to-normal RR intervals (SDNN) and the square root of the mean squared differences of successive RR intervals (rMSSD) were significantly higher at the end of the study in groups A (by 13.2% and 47.3%), B (by 15.1% and 50%), and C (by 9.0% and 30.1%), compared to group D (p < 0.05). Values of rMSSD and percentage of RR intervals differing by more than 50 ms from the preceding RR interval (pNN50) were elevated in groups A (by 35.6% and 142.9%), B (by 36.1% and 75%), and C (by 15.2% and 28.6%), compared to baseline measurements (p < 0.05). Also, pNN50 was increased in group A compared to groups B (by 21.4%), C (by 88.9%), and D (by 142.9%) (p < 0.05). Similar results were noted by short-term HRV analysis. Functional capacity was improved at the end of the 6-month study in groups A (by 20.3% and 25.7%) and B (by 15.8% and 21.1%) compared to groups C and D (p < 0.05). Conclusions: Intradialytic exercise combined with music-listening can improve the functional capacity and cardiac autonomic nervous system activity in hemodialysis patients.

Metabolic and functional effects of exercise training in diabetic kidney transplant recipients

BACKGROUND

Physical activity levels are significantly lower in kidney transplant (KT) recipients compared to the general population. The effects of exercise training in KT recipients with diabetes mellitus remain unclear, and so little is known about the role of increased exercise on cardiovascular risk and metabolic profile of KT patients.

AIM

To investigate the effects of a 6-mo home-based exercise training program on functional capacity, glucose levels and lipid profile of diabetic KT patients.

METHODS

In total, 21 type II diabetic KT recipients were randomly assigned into two groups: Exercise (n = 11, aged 52.9 ± 10.1 years) and control (n = 10, aged 53.01 ± 9.5 years). All participants at baseline and the end of the study underwent biochemical tests for fasting plasma glucose levels, glycated hemoglobin and lipid profile and cardiopulmonary exercise testing for maximum oxygen uptake [(VO₂)_peak] estimation. The exercise group followed a 6-mo supervised home-based aerobic and progressive resistance exercise program of moderate intensity 3 times per week, while the control group continued to receive usual care.

RESULTS

At the end of the 6-mo study, the exercise group had significantly lower values in fasting plasma glucose by 13.4% (from 120.6 ± 28.9 mg/dL to 104.8 ± 21.9 mg/dL, P = 0.01), glycated hemoglobin by 1.5% (from 6.7% ± 0.4 to 6.6% ± 0.4, P = 0.01) and triglycerides by 8.5% (from 164.7 ± 14.8 mg/dL to 150.8 ± 11.6 mg/dL, P < 0.05) and higher values in high-density lipoprotein by 10.2% (from 51.4 ± 8.8 mg/dL to 57.2 ± 8.7 mg/dL, P < 0.05) and (VO₂)_peak by 4.7% (from 22.7 ± 3.3 to 23.8 ± 4.2, P = 0.02) than the control group. There were statistically significant differences between the two groups at the end of the study for fasting plasma glucose (decreased by 9.6%, P < 0.05), triglycerides (decreased by 4.5%, P = 0.04) and (VO₂)_peak (increased by 4.4%, P = 0.01). Finally, after training, there was a moderate, positive linear relationship between (VO₂)_peak and glycated hemoglobin in the exercise group (r = 0.408, P = 0.03).

CONCLUSION

The results demonstrated that a 6-mo home-based mixed type exercise training program can improve the functional capacity, levels of glucose and lipid profile of diabetic KT recipients.

Nomogram Model Based on Clinical Risk Factors and Heart Rate Variability for Predicting All-Cause Mortality in Stage 5 CKD Patients

Background: Heart rate variability (HRV), reflecting circadian rhythm of heart rate, is reported to be associated with clinical outcomes in stage 5 chronic kidney disease (CKD5) patients. Whether CKD related factors combined with HRV can improve the predictive ability for their death remains uncertain. Here we evaluated the prognosis value of nomogram model based on HRV and clinical risk factors for all-cause mortality in CKD5 patients.

Methods: CKD5 patients were enrolled from multicenter between 2011 and 2019 in China. HRV parameters based on 24-h Holter and clinical risk factors associated with all-cause mortality were analyzed by multivariate Cox regression. The relationships between HRV and all-cause mortality were displayed by restricted cubic spline graphs. The predictive ability of nomogram model based on clinical risk factors and HRV were evaluated for survival rate.

Results: CKD5 patients included survival subgroup (n = 155) and all-cause mortality subgroup (n = 45), with the median follow-up time of 48 months. Logarithm of standard deviation of all sinus R-R intervals (lnSDNN) (4.40 ± 0.39 vs. 4.32 ± 0.42; p = 0.007) and logarithm of standard deviation of average NN intervals for each 5 min (lnSDANN) (4.27 ± 0.41 vs. 4.17 ± 0.41; p = 0.008) were significantly higher in survival subgroup than all-cause mortality subgroup. On the basis of multivariate Cox regression analysis, the lnSDNN (HR = 0.35, 95%CI: 0.17–0.73, p = 0.01) and lnSDANN (HR = 0.36, 95% CI: 0.17–0.77, p = 0.01) were associated with all-cause mortality, their relationships were negative linear. Spearman’s correlation analysis showed that lnSDNN and lnSDANN were highly correlated, so we chose lnSDNN, sex, age, BMI, diabetic mellitus (DM), β-receptor blocker, blood glucose, phosphorus and ln intact parathyroid hormone (iPTH) levels to build the nomogram model. The area under the curve (AUC) values based on lnSDNN nomogram model for predicting 3-year and 5-year survival rates were 79.44% and 81.27%, respectively.

Conclusion: In CKD5 patients decreased SDNN and SDANN measured by HRV were related with their all-cause mortality, meanwhile, SDNN and SDANN were highly correlated. Nomogram model integrated SDNN and clinical risk factors are promising for evaluating their prognosis.

Two Laparotomy Surgeries to Achieve Hemostasis After Kidney Transplantation in a Patient With Frailty: A Case Report

BACKGROUND

The assessment of frailty before and after kidney transplantation is becoming more important in the aging population. It is recommended to recognize the post-transplant risks and establish a treatment strategy. We report the case of a patient who underwent 2 laparotomy hemostasis procedures due to frailty after kidney transplantation.

CASE REPORT

A 72-year-old woman presented with end-stage renal failure due to an unknown primary disease. She was also found to be frail when assessed using the physical frailty phenotype. She underwent ABO-incompatible kidney transplantation from her husband at the end of March 2020. On the first postoperative day, re-operation for hematoma evacuation was performed. The bleeding point could not be identified at that time. Progression of anemia was observed on the sixth postoperative day, and computed tomography showed no obvious bleeding. Subsequently, the renal allograft started functioning immediately, without rejection. However, emergency laparotomy for hematoma removal was performed on the 22nd postoperative day. Bleeding had occurred from the anastomotic region of the renal allograft artery and the external iliac artery. Her serum creatinine levels and renal function remained stable one month after surgery.

CONCLUSIONS

We encountered a case of living-donor kidney transplantation in a frail older woman who underwent 2 laparotomies due to hemorrhage. Perioperative risk management is necessary for patients with a high risk of postoperative bleeding. To ensure a good outcome, preoperative and postoperative rehabilitation is important for patients with frailty.

Exercise training for adult lung transplant recipients

BACKGROUND

Pulmonary transplantation is the final treatment option for people with end-stage respiratory diseases. Evidence suggests that exercise training may contribute to speeding up physical recovery in adults undergoing lung transplantation, helping to minimize or resolve impairments due to physical inactivity in both the pre- and post-transplant stages. However, there is a lack of detailed guidelines on how exercise training should be carried out in this specific sub-population.

OBJECTIVES

To determine the benefits and safety of exercise training in adult patients who have undergone lung transplantation, measuring the maximal and functional exercise capacity; health-related quality of life; adverse events; patient readmission; pulmonary function; muscular strength; pathological bone fractures; return to normal activities and death.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register up to 6 October 2020 using relevant search terms for this review. Studies in the CKTR are identified through CENTRAL, MEDLINE, and EMBASE searches, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) were included comparing exercise training with usual care or no exercise training, or with another exercise training program in terms of dosage, modality, program length, or use of supporting exercise devices. The study population comprised of participants older than 18 years who underwent lung transplantation independent of their underlying respiratory pathology.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed all records identified by the search strategy and selected studies that met the eligibility criteria for inclusion in this review. In the first instance, the disagreements were resolved by consensus, and if this was not possible the decision was taken by a third reviewer. The same reviewers independently extracted outcome data from included studies and assessed risk of bias. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

Eight RCTs (438 participants) were included in this review. The median sample size was 60 participants with a range from 16 to 83 participants. The mean age of participants was 54.9 years and 51.9% of the participants were male. The median duration of the exercise training programs for the groups undergoing the intervention was 13 weeks, and the median duration of training in the active control groups was four weeks. Overall the risk of bias was considered to be high, mainly due to the inability to blind the study participants and the selective reporting of the results. Due to small number of studies included in this review, and the heterogeneity of the intervention and outcomes, we did not obtain a summary estimate of the results. Two studies comparing resistance exercise training with no exercise reported increases in muscle strength and bone mineral density (surrogate outcomes for pathological bone fractures) with exercise training (P > 0.05), but no differences in adverse events. Exercise capacity, health-related quality of life (HRQoL), pulmonary function, and death (any cause) were not reported. Three studies compared two different resistant training programs. Two studies comparing squats using a vibration platform (WBVT) compared to squats on the floor reported an improvement in 6-minute walk test (6MWT) (28.4 metres, 95% CI 3 to 53.7; P = 0.029; and 28.3 metres, 95% CI 10.0 to 46.6; P < 0.05) with the WBVT. Supervised upper limb exercise (SULP) program improved 6MWT at 6 months compared to no supervised upper limb exercise (NULP) (SULP group: 561.2 ± 83.6 metres; NULP group: 503.5 ± 115.2 metres; P = 0.01). There were no differences in HRQoL, adverse events, muscular strength, or death (any cause). Pulmonary function and pathological bone fractures were not reported. Two studies comparing multimodal exercise training with no exercise reported improvement in 6MWT at 3 months (P = 0.008) and at 12-months post-transplant (P = 0.002) and muscular strength (quadriceps force (P = 0.001); maximum leg press (P = 0.047)) with multimodal exercise, but no improvement in HRQoL, adverse events, pulmonary function, pathological bone fractures (lumbar T-score), or death (any cause). One study comparing the same multimodal exercise programs given over 7 and 14 weeks reported no differences in 6MWT, HRQoL, adverse events, pulmonary function, muscle strength, or death (any cause). Pathological bone fractures were not reported. According to GRADE criteria, we rated the certainty of the evidence as very low, mainly due to the high risk of bias and serious imprecision.

AUTHORS' CONCLUSIONS

In adults undergoing lung transplantation the evidence about the effects of exercise training is very uncertain in terms of maximal and functional exercise capacity, HRQoL and safety, due to very imprecise estimates of effects and high risk of bias.

Effects of Acute Stretching Exercise and Training on Heart Rate Variability: A Review

ABSTRACT

Wong, A and Figueroa, A. Effects of acute stretching exercise and training on heart rate variability: A review. J Strength Cond Res 35(5): 1459-1466, 2021-Stretching (ST), an exercise modality widely used for flexibility improvement, has been recently proposed as an effective adjunct therapy for declines in cardiovascular health, warranting research into the effects of ST exercise on cardiac autonomic function (CAF). Heart rate (HR) variability (HRV) is a reliable measure of CAF, mainly the sympathetic and parasympathetic modulations of HR. A low HRV has been associated to increased risk of cardiovascular events and mortality. Exercise interventions that enhance HRV are therefore seen as beneficial to cardiovascular health and are sought after. In this review, we discuss the effect of ST both acute and training on HRV. Stretching training seems to be a useful therapeutic intervention to improve CAF in different populations. Although the mechanisms by which ST training improves CAF are not yet well understood; increases in baroreflex sensitivity, relaxation, and nitric oxide bioavailability seem to play an important role.

The effects of exercise training in adult solid organ transplant recipients: A systematic review and meta-analysis

Reduced exercise capacity can predispose solid organ transplant (SOT) recipients to higher risk of diabetes, cardiovascular complications, and mortality and impact their quality of life. This systematic review and meta-analysis investigated the effects of exercise training (versus no training) in adult SOT recipients. We conducted an electronic search of randomized controlled trials reporting on exercise interventions in SOT recipients. Primary outcomes were exercise capacity, quadriceps muscle strength, and health-related quality of life (HRQoL). Twenty-nine articles met the inclusion criteria. In 24 studies, there were either high risk of bias or some concerns about the potential risk of bias. There was an increase in exercise capacity (VO₂ peak) (SMD: 0.40; 95%CI 0.22-0.57; P = 0.0) and quadriceps muscle strength (SMD: 0.38; 95%CI 0.16-0.60; P = 0.001) in the exercise vs control groups. There were also improvements in several domains of the SF-36. Diastolic blood pressure improved in the exercise group compared to controls (SMD: -0.22; 95%CI -0.41-0.03; P = 0.02). Despite the considerable variation in exercise training characteristics and high risk of bias in the included studies, exercise training improved maximal exercise capacity, quadriceps muscle strength, HRQoL, and diastolic blood pressure and should be an essential part of the post-transplant care.

Exercise training in patients after kidney transplantation

Kidney transplantation is the treatment of choice for patients with end-stage renal disease. Next to the risk of allograft failure, major obstacles for disease-free survival after kidney transplantation include a higher incidence of cancer, infection and cardiovascular events. Risk factors for adverse clinical outcomes include pre-existent comorbidities, the introduction of an immunodeficient status and (lack of) lifestyle changes after transplantation. Indeed, physical inactivity and poor physical fitness are important targets to address in order to improve clinical outcomes after kidney transplantation. This review summarizes the current evidence on exercise training after kidney transplantation, derived from randomized controlled trials. As much as possible, results are discussed in the perspective of the Standardized Outcomes in Nephrology-Transplantation core outcomes, which were recently described as critically important outcome domains for trials in kidney transplant recipients.

An overview of frailty in kidney transplantation: measurement, management and future considerations

The construct of frailty was first developed in gerontology to help identify older adults with increased vulnerability when confronted with a health stressor. This article is a review of studies in which frailty has been applied to pre- and post-kidney transplantation (KT) populations. Although KT is the optimal treatment for end-stage kidney disease (ESKD), KT candidates often must overcome numerous health challenges associated with ESKD before receiving KT. After KT, the impacts of surgery and immunosuppression represent additional health stressors that disproportionately impact individuals with frailty. Frailty metrics could improve the ability to identify KT candidates and recipients at risk for adverse health outcomes and those who could potentially benefit from interventions to improve their frail status. The Physical Frailty Phenotype (PFP) is the most commonly used frailty metric in ESKD research, and KT recipients who are frail at KT (~20% of recipients) are twice as likely to die as nonfrail recipients. In addition to the PFP, many other metrics are currently used to assess pre- and post-KT vulnerability in research and clinical practice, underscoring the need for a disease-specific frailty metric that can be used to monitor KT candidates and recipients. Although frailty is an independent risk factor for post-transplant adverse outcomes, it is not factored into the current transplant program risk-adjustment equations. Future studies are needed to explore pre- and post-KT interventions to improve or prevent frailty.

Uremic Sarcopenia: Clinical Evidence and Basic Experimental Approach

Sustained physical activity extends healthy life years while a lower activity due to sarcopenia can reduce them. Sarcopenia is defined as a decrease in skeletal muscle mass and strength due not only to aging, but also from a variety of debilitating chronic illnesses such as cancer and heart failure. Patients with chronic kidney disease (CKD), who tend to be cachexic and in frail health, may develop uremic sarcopenia or uremic myopathy due to an imbalance between muscle protein synthesis and catabolism. Here, we review clinical evidence indicating reduced physical activity as renal function deteriorates and explore evidence-supported therapeutic options focusing on nutrition and physical training. In addition, although sarcopenia is a clinical concept and difficult to recapitulate in basic research, several in vivo approaches have been attempted, such as rodent subtotal nephrectomy representing both renal dysfunction and muscle weakness. This review highlights molecular mechanisms and promising interventions for uremic sarcopenia that were revealed through basic research. Extensive study is still needed to cast light on the many aspects of locomotive organ impairments in CKD and explore the ways that diet and exercise therapies can improve both outcomes and quality of life at every level.

Effects of exercise training on cardiovascular risk factors in kidney transplant recipients: a systematic review and meta-analysis

BACKGROUND

Whether exercise can improve cardiovascular health in kidney transplant recipients (KTRs) is unclear. Therefore, we performed a systematic review of the effects of exercise on cardiovascular risk factors in this population setting.

METHODS

Randomized control trials (RCTs) evaluating the impact of exercise on major clinical outcomes in KTRs were identified by searches in Cochrane CENTRAL, PubMed, EMBASE, OVID and CBM updated to December 2018. The main outcomes of interest were blood pressure, lipid profile, blood glucose level, arterial stiffness, kidney function, body weight, body mass index, exercise tolerance (VO2 peak) and quality of life (QOL).

RESULTS

After screening 445 studies in the database, we included 12 RCTs in the review and 11 RCTs for further qualitative analysis. The results indicate a significant improvement in small arterial stiffness [mean difference (MD): -1.14, 95% confidence interval (CI): -2.19-0.08, p = .03], VO2 peak (MD: 2.25, 95% CI: 0.54-3.69, p = .01), and QOL (MD: 12.87, 95% CI: 6.80-18.94, p < .01) after exercise intervention in KTRs. However, there is no evidence for an improvement in blood pressure, lipid profile, blood glucose level, kidney function, body weight or body mass index.

CONCLUSION

Exercise intervention in KTRs improves arterial stiffness but does not consistently contribute to the modification of other CVD risk factors like hypertension, dyslipidemia, hyperglycemia, decreased kidney function and obesity. Exercise also improves exercise tolerance and QOL in KTRs.

Does whole body vibration training improve heart rate variability in kidney transplants patients? A randomized clinical trial

BACKGROUND

Whole-body vibration (WBV) is an exercise modality that can promote improvements in heart rate variability (HRV) with lower patient overload, and consequently reduce cardiovascular risk in renal transplant patients. The aim of this study was to evaluate the effects of a 12-week WBV training program of two weekly sessions on HRV.

METHODS

A double-blind, randomized controlled clinical trial with 12 kidney transplant recipients of both genders who underwent WBV training (35 Hz) twice a week for 12 weeks on alternate days (WBV Group) and training with sub-therapeutic WBV (8 Hz) (Sham Group). Variables were evaluated in time and frequency domains of HRV through the 24-h Holter monitor, heart rate (HR), blood pressure (BP) and maximum oxygen consumption (VO_2max) through an exercise stress test.

RESULTS

The delta between Sham and WBV groups showed an increase in the low frequency (Δ = 959.05 Hz; p = 0.01) and in the high frequency (Δ = 204.42 Hz; p = 0.04) of the HRV compared to Sham group. No changes in the ergometric variables were observed for any of the groups.

CONCLUSION

The present study evidenced an increase in the low and high frequency of HRV in individuals who participated in the Sham WBV group. There was no improvement in the autonomic balance in the groups, in the other HRV parameters, or the exercise test after the WBV training period.

Physical Activity in the Prevention of Development and Progression of Kidney Disease in Type 1 Diabetes

PURPOSE OF REVIEW

Physical activity is a fundamental part of lifestyle management in diabetes care. Although its benefits are very well recognized in the general population and in people with type 2 diabetes, much less is known about the effects of exercise in type 1 diabetes. In particular, exercise effects in relation to diabetic kidney disease (DKD) are understudied. Some uncertainties about physical activity recommendations stem from the fact that strenuous exercise may worsen albuminuria immediately after the activity. However, in middle-aged and older adults without diabetes, observational studies have suggested that physical activity is associated with a decreased risk of rapid kidney function deterioration. In this review, we focus on the role of physical activity in patients with DKD and type 1 diabetes.

RECENT FINDINGS

Hereby, we present data that show that in individuals at risk of DKD or with established DKD, regular moderate-to-vigorous physical activity was associated with reduced incidence and progression of DKD, as well as reduced risk of cardiovascular events and mortality. Therefore, regular moderate-to-vigorous exercise should become a central part of the management of individuals with type 1 diabetes, in the absence of contraindications and accompanied with all needed educational support for optimal diabetes management.

Effects of whole body vibration on cardiac autonomic function and exercise capacity in renal transplant recipients

Background/Aims

Whole body vibration is an exercise alternative that can be used in the rehabilitation of renal transplant recipients with the aim of reducing cardiovascular risk. The aim of this study was to evaluate the effects of whole body vibration training on heart rate variability, cardiorespiratory parameters and functional capacity on five renal transplant recipients.

Methods

Renal transplant recipients underwent whole body vibration exercise twice a week for a total of 12 weeks. All participants were monitored using the 24-hour Holter to evaluate the heart rate variability domains. An exercise test to evaluate maximal oxygen consumption and the distance walked in the Six-Minute Walk Test to evaluate functional capacity were also recorded.

Results

Overall, two of the five transplant recipients improved sympathovagal balance at the end of the study. Maximal oxygen consumption improved in three transplanted patients, and the distance walked improved for two patients. The results showed that whole body vibration training improved heart rate variability and maximal and submaximal test performance in some transplanted recipients.

Conclusion

The 12-week training protocol with twice weekly whole body vibration sessions was sufficient to improve heart rate variability and the performance of maximal and submaximal tests in some renal transplant recipients, although the responses were heterogeneous for the considered variables. Whole body vibration may be an alternative to conventional means of physical exercise because it causes minimal cardiovascular stress, which could be especially indicated for this population given the risk presence of arrhythmias and sudden death; therefore studies with better designs need to be developed in order to verify the effectiveness of this intervention.

Meta-Analysis of the Effects of Exercise Training on Markers of Metabolic Syndrome in Solid Organ Transplant Recipients

Background:

The markers of metabolic syndrome can prompt the development of metabolic syndrome and are associated with worse graft function among transplant recipients. Studies have shown that exercise might be effective in reducing incidence rate of metabolic syndrome components in nontransplant patients. However, there is no sufficient evidence to determine whether exercise training is safe or effective for markers of metabolic syndrome among solid organ transplant recipients.

Objective:

To evaluate the safety and efficacy of exercise training programs for risk markers of metabolic syndrome and to further evaluate its long-term effects in solid organ transplant recipients.

Methods:

We systematically reviewed all randomized trials comparing the outcomes of exercise training in organ transplant recipients. The Cochrane Library, Joanna Briggs Institute EBP Database, PubMed, Embase, Web of Science Core Collection, ProQuest Health & Medical Complete, and SinoMed databases were searched to June 2017. The meta-analysis was conducted using RevMan 5.3.

Results:

In total, 13 eligible trails involving 464 patients were included. Recipients who engaged in an exercise program after transplantation showed significant reductions in fasting blood glucose, diastolic blood pressure, triglycerides, and body mass index and a significant increase in high-density lipoprotein. But found no significant changes in new-onset diabetes, systolic blood pressure, total cholesterol, or low-density lipoprotein.

Conclusion:

Exercise training may be a promising intervention for markers of metabolic syndrome in transplant recipients. Further research is required to determine essential aspects of exercise according to organ transplantation type for effects on markers of metabolic syndrome.

Effects of whole-body vibration on heart rate variability: acute responses and training adaptations

Heart rate variability (HRV) is a noninvasive and practical measure of cardiac autonomic nervous system function, mainly the sympathetic and parasympathetic modulations of heart rate. A low HRV has been shown to be indicative of compromised cardiovascular health. Interventions that enhance HRV are therefore beneficial to cardiovascular health. Whole-body vibration (WBV) training has been proposed as an alternative time-efficient exercise intervention for the improvement of cardiovascular health. In this review, we discuss the effect of WBV both acute and after training on HRV. WBV training appears to be a useful therapeutic intervention to improve cardiac autonomic function in different populations, mainly through decreases in sympathovagal balance. Although the mechanisms by which WBV training improves symphathovagal balance are not yet well understood; enhancement of baroreflex sensitivity, nitric oxide bioavailability and angiotensin II levels seem to play an important role.

Renal function and physical fitness after 12-mo supervised training in kidney transplant recipients

AIM

To evaluate the effect of a 12-mo supervised aerobic and resistance training, on renal function and exercise capacity compared to usual care recommendations.

METHODS

Ninety-nine kidney transplant recipients (KTRs) were assigned to interventional exercise (Group A; n = 52) and a usual care cohort (Group B; n = 47). Blood and urine chemistry, exercise capacity, muscular strength, anthropometric measures and health-related quality of life (HRQoL) were assessed at baseline, and after 6 and 12 mo. Group A underwent a supervised training three times per week for 12 mo. Group B received only general recommendations about home-based physical activities.

RESULTS

Eighty-five KTRs completed the study (Group A, n = 44; Group B, n = 41). After 12 mo, renal function remained stable in both groups. Group A significantly increased maximum workload (+13 W, P = 0.0003), V’O₂ peak (+3.1 mL/kg per minute, P = 0.0099), muscular strength in plantar flexor (+12 kg, P = 0.0368), height in the countermovement jump (+1.9 cm, P = 0.0293) and decreased in Body Mass Index (-0.5 kg/m², P = 0.0013). HRQoL significantly improved in physical function (P = 0.0019), physical-role limitations (P = 0.0321) and social functioning scales (P = 0.0346). No improvements were found in Group B.

CONCLUSION

Twelve-month of supervised aerobic and resistance training improves the physiological variables related to physical fitness and cardiovascular risks without consequences on renal function. Recommendations alone are not sufficient to induce changes in exercise capacity of KTRs. Our study is an example of collaborative working between transplant centres, sports medicine and exercise facilities.

Physical Activity in Kidney Transplant Recipients: A Review

Physical activity has known health benefits and is associated with reduced cardiovascular risk in the general population. Relatively few data are available for physical activity in kidney transplant recipients. Compared to the general population, physical activity levels are lower overall in kidney recipients, although somewhat higher compared to the dialysis population. Recipient comorbid condition, psychosocial and socioeconomic factors, and long-term immunosuppression use negatively affect physical activity. Physical inactivity in kidney recipients may be associated with reduced quality of life, as well as increased mortality. Interventions such as exercise training appear to be safe in kidney transplant recipients and are associated with improved quality of life and exercise capacity. Additional studies are required to evaluate long-term effects on cardiovascular risk factors and ultimately cardiovascular disease outcomes and patient survival. Currently available data are characterized by wide variability in the interventions and outcome measures investigated in studies, as well as use of small sample-sized cohorts. These limitations highlight the need for larger studies using objective and standardized measures of physical activity and physical fitness in kidney transplant recipients.

Relationship between declining glomerular filtration rate and measures of cardiac and vascular autonomic neuropathy

AIM

Cardiac and vascular autonomic neuropathy contributes to increased morbidity and mortality in patients with chronic kidney disease. The aim of this study was to analyze the effects of a decline in glomerular filtration rate (GFR) on heart rate variability (HRV) and nocturnal blood pressure dipping.

METHODS

This cross-sectional study comprises 124 patients (46 women, 78 men; age 66 ± 14 years) with chronic kidney disease (CKD) 3-5, not on renal replacement therapy. GFR was measured with iohexol clearance, HRV with 24 h Holter electrocardiogram (ECG) and nocturnal dipping with 24 hour ambulatory blood pressure.

RESULTS

The GFR was 22.5 ± 8.5 mL/min per 1.73 m² . The main finding was a significant curvilinear association between the 24 h standard deviation of NN interval (24SDNN) in the HRV analysis and GFR (P = 0.01), logGFR (P = 0.006), diabetes mellitus (P = 0.05) and beta blocker treatment (0.03), respectively. The effect of diabetes mellitus on 24SDNN corresponded to a decline in GFR from 30 to 12 mL/min per 1.73 m² . There were significant curvilinear associations between systolic nocturnal dipping (P = 0.02) and diastolic nocturnal dipping (P = 0.05), respectively, and diabetes mellitus but not with GFR or logGFR.

CONCLUSION

In conclusion, cardiac sympathetic overdrive and decreased vagal control appear during CKD 4 and 5. The association with GFR is curvilinear. Diabetes mellitus was significantly associated with both cardiac and vascular autonomic neuropathy, as measured by heart rate variability and nocturnal blood pressure dipping, respectively. Knowing that arrhythmias, often due to sympathetic hyperactivity, are an important cause of sudden death in the dialysis population, this study contributes important knowledge on possible intervention thresholds.

Long-term pulse wave velocity outcomes with aerobic and resistance training in kidney transplant recipients - A pilot randomised controlled trial

BACKGROUND

This pilot study examined long-term pulse wave velocity (PWV) and peak oxygen uptake (VO2peak) outcomes following a 12-week moderate-intensity aerobic or resistance training programme in kidney transplant recipients.

METHOD

Single-blind, bi-centre randomised controlled parallel trial. 42 out of 60 participants completed a 9-month follow-up assessment (Aerobic training = 12, Resistance training = 10 and usual care = 20). Participants completed 12 weeks of twice-weekly supervised aerobic or resistance training. Following the 12-week exercise intervention, participants were transitioned to self-managed community exercise activity using motivational interviewing techniques. Usual care participants received usual encouragement for physical activity during routine clinical appointments in the transplant clinic. PWV, VO2peak, blood pressure and body weight were assessed at 12 weeks and 12 months, and compared to baseline.

RESULTS

ANCOVA analysis, covarying for baseline values, age, and length of time on dialysis pre-transplantation, revealed a significant mean between-group difference in PWV of -1.30 m/sec (95%CI -2.44 to -0.17, p = 0.03) between resistance training and usual care groups. When comparing the aerobic training and usual care groups at 9-month follow-up, there was a mean difference of -1.05 m/sec (95%CI -2.11 to 0.017, p = 0.05). A significant mean between-group difference in relative VO2peak values of 2.2 ml/kg/min (95% CI 0.37 to 4.03, p = 0.02) when comparing aerobic training with usual care was revealed. There was no significant between group differences in body weight or blood pressure. There were no significant adverse effects associated with the interventions.

CONCLUSIONS

Significant between-group differences in 9-month follow-up PWV existed when comparing resistance exercise intervention with usual care. A long-term between-group difference in VO2peak was only evident when comparing aerobic intervention with usual care. This pilot study, with a small sample size, did not aim to elucidate mechanistic mediators related to the exercise interventions. It is however suggested that a motivational interviewing approach, combined with appropriate transition to community training programmes, could maintain the improvements gained from the 12-week exercise interventions and further research in this area is therefore warranted.

TRIAL REGISTRATION

study number: ISRCTN43892586.

Outcomes in randomized controlled trials of exercise interventions in solid organ transplant

AIM

To identify the outcome measures that have been used in randomized controlled trials (RCTs) of exercise training in solid organ transplant (SOT) recipients and to link these outcomes to the International Classification of Functioning, Disability and Health (ICF) framework.

METHODS

Electronic literature searches of MEDLINE, EMBASE, CINAHL, Cochrane, Scopus, and Web of Science were performed. We sought RCTs that investigated the effect of exercise training in SOT recipients. Reference lists of all eligible publications were searched for other appropriate studies not identified by the electronic search. A complete list of outcome measures used in the RCTs was generated and each of these was linked to an ICF category.

RESULTS

Four hundred and thirteen articles were retrieved, of which 35 met our inclusion criteria. The studies included were designed to compare the effects of exercise training programs to usual care or to another exercise training program and reported on recipients of heart (n = 21), kidney (n = 9), lung (n = 3) or liver (n = 2) transplant. Of the 126 outcome measures identified, 62 were used as primary outcome measures. The most commonly occurring primary outcomes were aerobic capacity using the peak VO₂ (n = 13), quality of life using the short-form-36 (n = 8), and muscle strength (n = 7). These outcome measures were linked to 113 ICF categories and the majority of outcomes fall into the body function domain (n = 93).

CONCLUSION

There is little standardization in outcome measures used in RCTs of exercise interventions in SOT recipients. The ICF framework can be used to select a core set of outcomes that cross all domains of ICF and that would be appropriate to all SOT recipients.

An Integrative Literature Review of Physical Activity Recommendations for Adult Renal Transplant Recipients

OBJECTIVE

To establish the current state of knowledge regarding physical activity interventions for adult kidney transplant recipients.

DATA SOURCES

A comprehensive literature search was conducted for the years 2009 to 2015 using 5 electronic databases: PubMed, CINAHL, Cochrane Library, Ovid, and ScienceDirect.

DATA EXTRACTION

Of the 110 articles identified, only 6 met inclusion requirements. These studies were conducted between 2009 and 2015 and found that weight gain was reported most often within the first year of transplantation and that kidney transplant recipients desired early interventions to help them become more physically active.

CONCLUSION

Further research is recommended to design age-appropriate physical activity interventions among this aging population living with a chronic condition known to have a high prevalence of obesity and cardiovascular disease.

Effects of exercise in the whole spectrum of chronic kidney disease: a systematic review

Chronic kidney disease (CKD) is a public health problem. Although physical activity is essential for the prevention and treatment of most chronic diseases, exercise is rarely prescribed for CKD patients. The objective of the study was to search for and appraise evidence on the effectiveness of exercise interventions on health endpoints in CKD patients. A systematic review was performed of randomized clinical trials (RCTs) designed to compare exercise with usual care regarding effects on the health of CKD patients. MEDLINE, EMBASE, Cochrane Central, Clinical Trials registry, and proceedings of major nephrology conference databases were searched, using terms defined according to the PICO (Patient, Intervention, Comparison and Outcome) methodology. RCTs were independently evaluated by two reviewers. A total of 5489 studies were assessed for eligibility, of which 59 fulfilled inclusion criteria. Most of them included small samples, lasted from 8 to 24 weeks and applied aerobic exercises. Three studies included only kidney transplant patients, and nine included pre-dialysis patients. The remaining RCTs allocated hemodialysis patients. The outcome measures included quality of life, physical fitness, muscular strength, heart rate variability, inflammatory and nutritional markers and progression of CKD. Most of the trials had high risk of bias. The strongest evidence is for the effects of aerobic exercise on improving physical fitness, muscular strength and quality of life in dialysis patients. The benefits of exercise in dialysis patients are well established, supporting the prescription of physical activity in their regular treatment. RCTs including patients in earlier stages of CKD and after kidney transplantation are urgently required, as well as studies assessing long-term outcomes. The best exercise protocol for CKD patients also remains to be established.

Aerobic or Resistance Training and Pulse Wave Velocity in Kidney Transplant Recipients: A 12-Week Pilot Randomized Controlled Trial (the Exercise in Renal Transplant [ExeRT] Trial)

BACKGROUND

Cardiovascular disease remains the leading cause of death in kidney transplant recipients. This pilot study examined the potential effect of aerobic training or resistance training on vascular health and indexes of cardiovascular risk in kidney transplant recipients.

STUDY DESIGN

Single-blind, randomized, controlled, parallel trial.

SETTING & PARTICIPANTS

60 participants (mean age, 54 years; 34 men) were randomly assigned to aerobic training (n=20), resistance training (n=20), or usual care (n=20). Participants were included if they had a kidney transplant within 12 months prior to baseline assessment. Patients were excluded if they had unstable medical conditions or had recently started regular exercise.

INTERVENTION

Aerobic training and resistance training were delivered 3 days per week for a 12-week period. The usual-care group received standard care.

OUTCOMES & MEASUREMENTS

Pulse wave velocity, peak oxygen uptake (Vo2peak), sit-to-stand 60, isometric quadriceps force, and inflammatory biomarkers were assessed at 0 and 12 weeks.

RESULTS

The anticipated 60 participants were recruited within 12 months. 46 participants completed the study (aerobic training, n=13; resistance training, n=13; and usual care, n=20), resulting in a 23% attrition rate. Analyses of covariance, adjusted for baseline values, age, and dialysis vintage pretransplantation, revealed significant mean differences between aerobic training and usual care in pulse wave velocity of -2.2±0.4 (95% CI, -3.1 to -1.3) m/s (P<0.001) and between resistance training and usual care of -2.6±0.4 (95% CI, -3.4 to -1.7) m/s (P<0.001) at 12 weeks. Secondary analyses indicated significant improvements in Vo2peak in the aerobic training group and in Vo2peak, sit-to-stand 60, and isometric muscle force in the resistance training group compared with usual care at 12 weeks. There were no reported adverse events, cardiovascular events, or hospitalizations as a result of the intervention.

LIMITATIONS

Pilot study, small sample size, no measure of endothelial function.

CONCLUSIONS

Both aerobic training and resistance training interventions appear to be feasible and clinically beneficial in this patient population.

Exercise training improves aerobic capacity, muscle strength, and quality of life in renal transplant recipients

Renal transplant recipients (RTR) have reduced peak aerobic capacity, muscle strength, arterial function and an unfavorable cardiovascular disease risk (CVD) profile. This study compared the effects of 12 weeks of supervised endurance and strength training (EST, n = 16) versus usual care (UC, n = 15) on peak aerobic capicity, cardiovascular and skeletal muscle function, CVD risk profile, and quality of life (QOL) in RTR (55 ± 13 years). Peak aerobic capacity and exercise hemodynamics, arterial compliance, 24-h blood pressure, muscle strength, lean body mass, CVD risk score, and QOL were assessed before and after 12 weeks. The change in peak aerobic capacity (EST: 2.6 ± 3.1 vs. UC: -0.5 ± 2.5 mL/(kg·min)), cardiac output (EST: 1.7 ± 2.6 vs. UC: -0.01 ± 0.8 L/min), leg press (EST: 48.7 ± 34.1 vs. UC: -10.5 ± 37.7 kg) and leg extension strength (EST: 9.5 ± 10.3 vs. UC: 0.65 ± 5.5 kg) improved significantly after EST compared with UC. The overall change in QOL improved significantly after 12 weeks of EST compared with UC. No significant difference was found between groups for lean body mass, arterial compliance, 24-h blood pressure or CVD risk score. Supervised EST is an effective intervention to improve peak exercise aerobic capacity and cardiac output, muscle strength and QOL in clinically stable RTR.

Potential side effects of unhealthy lifestyle choices and health risks on basal and reactive heart rate variability in college drinkers

OBJECTIVE

Emerging adults often begin making independent lifestyle choices during college, yet the association of these choices with fundamental indicators of health and adaptability is unclear. The present study examined the relationship between health risks and neurocardiac function in college drinkers.

METHOD

Heart rate variability (HRV) was assessed at baseline and in reaction to a paced breathing challenge in 212 college drinkers (53.8% women). Basal HRV served as a general indicator of health. Reactive HRV (during paced breathing) was used as a marker of an individual's adaptability to challenge. The relationship of HRV to alcohol use, cigarette use, exercise, sleep, and body mass index (BMI) was assessed.

RESULTS

Greater alcohol use and less exercise were associated with lower basal HRV. BMI was unrelated to basal HRV but was negatively associated with reactive HRV during the breathing challenge.

CONCLUSIONS

High levels of alcohol use and lack of exercise are negative correlates of cardiovascular and general health, even in apparently healthy college drinkers. The negative relationship between BMI and reactive HRV suggests that overweight individuals have reduced ability to psychophysiologically adapt to challenges; understanding the temporal course of this relationship is needed. This study highlights the importance of examining HRV at baseline and in response to a challenge to capture the active neurocardiac processes that contribute to health and adaptive responding. The suppressive effects of health risks on HRV are modifiable; thus, HRV may be useful in evaluating the health benefits of lifestyle change and in promoting change behaviors in college drinkers.