Non-Randomized Controlled Trial

C - Click here for explanation of classification scheme.

POSITIVE: See Quality Criteria Checklist below.

To investigate the effects of a multi-modal intervention program consisting of:

• Nutrition management preventing cachexia or obesity
• Controlled exercise training
• Psychosocial counseling on respective outcome parameters in outpatients on long-term LVAD support.

• They were being followed up at the LVAD outpatient clinic while being on LVAD support
• A minimum of 18 years old
• Provided written informed consent.

• Insufficient language skills to read and answer the battery of questionnaires
• Showed symptoms of tachycardia with anti-arrhythmic medical treatment
• Had orthopedic limitations that precluded exercise testing or training.

Recruitment

Patients over the age of 18 years old at the LVAD outpatient clinic who were being followed for LVAD support.

Design

Prospective, multi-modal intervention study.

Intervention

• Intervention consisted of three modules:
  • Nutrition management:
    •  Four basic one-on-one educational sessions with a dietitian were offered at consecutive outpatient visits on general nutrition guidelines and healthy food habits
    • Written materials were also provided at each of the four sessions, along with an individualized nutrition intervention based on the patients’ body mass index (BMI) and the families’ lifestyle and nutritional habits:
      • Session One: Information on "What Is Healthy Nutrition?"
      • Session Two: Focused on "What Is Important to Know About a Healthy Lifestyle"
      • Session Three: Discussed "Energy—How Does It Work"
      • Session Four: Focused on "Nutrition and Psyche—Healthy Eating Is Caring for Our Soul."
    • Phone call every 14 days after study inclusion for:
      • Single patients
      • Those having a BMI outside normal ranges (less than 19 or more than 25)
      • Those cases with an increased weight gain (four or more pounds).

    • Phone calls every four weeks after study inclusion for:

      • Those patients with a BMI within normal ranges
      • When the patient had gained less than four pounds within the last month.
  • Physical reconditioning program:
    • Home-based physical reconditioning:
      • Patients were equipped with a bicycle ergometer and a tailored, home-based, smartcard-guided ergometry training program
      • Supplemented by regular phone calls for psychosocial support and training updates to keep patients motivated for exercise training
      • Patients were recommended to exercise every other day
      • Reference values for the training program were calculated based on cardiopulmonary exercise testing at the baseline and were readjusted based on repeated exercise testing
      • Both the individualized training program and training data were stored on the smartcard. These data were transferred to the central database.
  • Psychosocial support and counseling:
    • Offered to both patients and their partners:
      • Emphasis on psychosocial support using stabilizing and resource-activating strategies
      • Problem-solving, coping with fear, anger and depression were part of discussions
      • Support provided face-to-face and by phone as requested by the patient or his or her relative
      • The initial contacts were made either during the implant, in-hospital stay or in the outpatient clinic.
• Behavior modifying strategies consisted of patient and family education, realistic goal setting, feedback and motivation for all three modules.

Statistical Analysis

• Descriptive statistics were used for time-dependent continuous variables
• Frequencies were generated for other variables
• Inferential statistics included cross-tabulations, X² or non-parametric tests to compare baseline and follow-up characteristics
• Analyses were performed using intention-to-treat principles
• Repeated measures analysis of variance, with one within-subjects factor being time and one between-subjects factor being group, was used to determine the differences between the groups as a function of time
• Addressing the risk of Type I error inflation, individual P-values were Bonferroni–Holm adjusted for multiple testing
• Effect size calculations based on the Cohen’s Kappa were performed to estimate whether the BMI groups differed by the chance as impacted by the sample size
• The level of significance was set at P<0.05
• Data analyses were performed using SPSS statistical software for windows.

Timing of Measurements

Tested at six weeks (baseline) and at six, 12 and 18 months while being on LVAD support.

Dependent Variables

• Body mass index (BMI):
  • Measured as weight in kg/m²; values were retrieved from the patient charts
  • BMI target values for this intervention were between 18.5kg/m² and 25.0kg/m².
• Cardiopulmonary exercise testing:
  • The maximum exercise capacity was assessed by CPET diagnostics on a bicycle ergometer, including an oxygen delta module to allow for respiratory gas analysis on a breath-by-breath basis
  • Data values were collected on the maximum workload in watts (W) and on the maximum oxygen consumption (VO_2max), including the age and gender-adjusted reference values
  • The pump speed was adjusted individually in each patient, to allow maximum support while avoiding suction events. Adjustments were made based on the repeated echocardiography and the LVAD data download.
• Medical outcomes survey SF-36:
  • The German-validated version was used
  • Consists of 36 items on eight sub-scales exploring subjectively perceived HRQoL (health-related quality of life) by the individual
  • The physical component scale (PCS) capture scales on physical functioning, role physical, bodily pain and general health
  • The mental component scale (MCS) refers to patients’ perceptions on vitality, social functioning, role of emotional and mental health.
  • Scores range between zero and 100, with higher scores indicating the better HRQoL.
• Hospital anxiety and depression scale:
  • Validated screening tool for the symptoms of anxiety and depression, with an exclusion of the confounding effects of the somatic symptoms of a physical disorder
  • The instrument consists of two scales of seven items capturing the symptoms of anxiety and seven items on depression
  • Scores ranging between zero and seven can be interpreted as normal, eight to 10 mild, 11 to 14 moderate and 15 to 21 severe symptoms of anxiety or depression.

Independent Variables

Patients were consecutively referred (randomized) to the intervention group or control group.

Control Variables

• Control group patients received standardized recommendations:
  • To stay on a healthy diet
  • To target the normal BMI ranges
  • To improve the physical fitness by exercising on a routine basis
  • To seek the psychosocial support, if necessary.
• Otherwise, no standardized interventions were given.

Initial N

N=70 patients [34 in the intervention group (IG) and 36 in the control group(CG)].

Attrition (Final N)

N=53 (24 in the intervention group and 26 in the control group n=26):

• Heart transplant (IGr N=5; CGr N=7)
• LVAD explanation due to recovery (IGr N=1)
• Withdraw of study consent (IGr N=1)
• Death of patient (IGr N=3, CGr N=3).

Age:

	Intervention (N=34)	Control (N=36)	Coefficient	P-value
Age [years (median ± SE)]	52±2	51±2	z=−1.39	0.16

 

Other Relevant Demographics

	Intervention (N=34)	Control (N=36)	Coefficient	P-value
Demographic variables
Gender (percent male)	85.4	87.5	X2=2.33	0.13
Family (percent married)	48.8	58.2	X2=5.37	0.25
Education (percent higher)	37.9	44.5		0.09
Clinical variables
Diagnosis leading to implant surgery
DCM (percent)	56.1	47.3	X2=1.98	0.58
CAD (percent)	43.9	49.1
Myocarditis (percent)	--	3.6
Hospital LOS post-implant (days)	42±16	46±21	z=−0.81	0.42
Health-related quality of life
SF-36 PCS	34.7±1.5	30.4±1.4	z=−1.38	0.66
SF-36 MCS	50.7±1.9	51.3±2.3	z=−0.67	0.51
Anxiety and depression scores (HADS)
HADS anxiety	2.0±0.6	5.0±0.6	z=−1.76	0.08
HADS depression	4.5±0.6	4.0±0.5	z=−0.18	0.85

CAD: coronary artery disease; CGr: control group; DCM: dilated cardiomyopathy; HADS: hospital anxiety and depression scale; IGr: intervention group; LOS: length of stay; LVAD: left ventricular assist device; SE: standard error; SF-36 PCS: physical component score; MCS: mental component score, with a score range of zero to 100 (higher scores indicate the better HRQoL perceptions). HADS score range (zero to 21): zero to seven, normal; eight to 10 mild; 11 to 14 moderate and 15 to 21 severe symptoms of anxiety or depression.


Anthropometrics

	Intervention (N=34)	Control (N=36)	Coefficient	P-value
Body weight and nutrition
Body weight [kg (median ± SE)]	74±2.2	74±2.4	z=−0.95	0.37
BMI [kg/m2 (median ± SE)]	24±0.6	24±0.6	z=−0.96	0.34
Physical exercise tolerance
Workload (W)	80.0±5.1	70.0±3.7	z=−1.10	0.27
VO2max (ml per minute per kg)	18.5±0.8	16.3±0.6	z=−1.57	0.17

BMI: body mass index; VO_2max: maximum oxygen consumption.

• Patients were on long-term rotary blood pump support as a bridge to transplantation with 54.8% being bridged with a Heartmate II (Thoratec, Pleassenton, CA, USA) and 45.2% being on Heartware (HeartWare, Inc., Miramar, FL, USA) support
• The baseline sample characteristics did not differ between the groups
• Sub-group analysis controlling for whether device type influenced the outcome variables of interest showed no significant differences for the BMI, exercise tolerance and for HRQoL outcomes.

Location:

Hanover, Germany.

Key Findings

BMI	Interventiona	Controla	95% CI	*P-Value	Effect Size
BMI six weeks	24.0 (22.4 to 28.5)	23.8 (21.8 to 27.5)	−2.41 to 1.35	<0.579	0.100
BMI six months	24.8 (22.8 to 28.1)	26.2 (22.4 to 28.4)	−1.65 to −0.71	<0.718	0.145
BMI 12 months	25.3 (22.7 to 28.8)	27.4 (23.9 to 9.4)	−0.73 to −0.09	<0.316	0.328
BMI 18 months	24.5 (22.5 to 28.7)	29.7 (24.4 to 30.9)	−0.71 to 0.69	<0.020	0.907

BMI: body mass index (kg/m²); CI: confidence interval. A Median (percentile 25 to 75). *Bonferroni–Holm adjusted.
 

Other Findings

• While being on the device, IGr patients remained within normal BMI ranges (P=0.35), whereas CGr patients significantly gained weight during the same time period (P=0.05)
• Assessing inter-group effects, the IGr and CGr patients’ BMI differed significantly at 18 months after implant (P=0.05), favoring IGr patients
• Effect size calculations were performed on the intensified nutrition management provided for the IGr patients and revealed a significant effect (EF=0.907; P=0.02) at T4
• The development of physical exercise tolerance, as determined by CPET diagnostics, revealed a significant increase in the workload for both groups during the course of the study
• IGr patients showed a significant increase in their age-adjusted and gender-adjusted workload as predicted (P=0.05); CGr patients’ workload also increased during this observation period (P=0.21), but did not reach the statistical significance after Bonferroni–Holm adjustment
• Group comparisons revealed a comparable workload between groups at the baseline (P=0.27), with IGr patients reaching higher workload levels compared with their counterparts (P=0.05) at the end of the study
• Age-adjusted and gender-adjusted VO_2max over time increased in both groups; however, this increase was significant only for IGr patients (P=0.01)
• The group comparisons showed a significant group difference in favor of IGr patients after the course of the study (P=0.05)
• The SF-36 showed a significant increase for HRQoL in the physical score for IGr patients (P=0.04), and a stable psychosocial score (P=0.79) over the course of the study when assessing for intra-subject effects
• IGr patients maintained symptoms within normal ranges (anxiety P=0.57; depression P=0.32) over the course of the study, whereas CGr patients reported anxiety levels approaching borderline for the abnormal scores (P=0.05).

• A multi-modal intervention consisting of nutrition management, controlled exercise training and psychosocial support showed a positive effect on patients’ self-management while on outpatient, long-term LVAD support
• This study demonstrated that preventive nutrition management, providing a combination of standardized educational and individualized sessions, was effective in preventing obesity
• A home-based ergometry training program resulted in improved exercise tolerance
• Psychosocial counseling support prevented psychological distress
• Nutrition and exercise management, as well as psychological assessment and intervention should become integral parts of the follow-up management for this population
• Cost-effectiveness studies are needed to investigate the economic implications of such intervention programs.

Other:

German Foundation of Heart Research and the German Federal Ministry of Education and Research