Causes and Consequences of Missing Health-Related Quality of Life Assessments in Patients Who Undergo Mechanical Circulatory Support Implantation: Insights From INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support)

Incompleteness of health-related quality of life assessments before left ventricular assist device implant: A novel quality metric

BACKGROUND

Improved health-related quality of life (HRQOL) is an important outcome following durable left ventricular assist device (LVAD) implant. However, half of pre-implant HRQOL data are incomplete in The Society of Thoracic Surgeons' Intermacs registry. Pre-implant HRQOL incompleteness may reflect patient status or hospital resources to capture HRQOL data. We hypothesized that pre-implant HRQOL incompleteness predicts 90 day outcomes and serves as a novel quality metric.

METHODS

Risk factors for pre-implant HRQOL (EQ-5D-5L visual analog scale; 12-item Kansas City Cardiomyopathy Questionnaire "KCCQ") incompleteness were examined by stepwise logistic modeling. Direct standardization method was used to calculate adjusted incompleteness rates using a mixed effects logistic model. Hospitals were dichotomized as low or high based on median adjusted incompleteness rates. Andersen-Gill models were used to associate pre-implant HRQOL adjusted incompleteness rate with adverse events within 90 day post-implant.

RESULTS

The study cohort included 14,063 patients receiving a primary LVAD (4/2012-8/2017). HRQOL incompleteness at high-rate hospitals was more often due to administrative reasons (risk difference, EQ-5D: 10.1%; KCCQ-12: 11.6%) and less likely due to patient reasons (risk difference, EQ-5D: -8.9%; KCCQ-12: -11.4%). A 10% increase in the adjusted pre-implant EQ-5D incompleteness rate was significantly associated with higher risk of infection-related mortality (HR: 1.09), infection (HR: 1.05), and renal dysfunction (HR: 1.03). A 10% increase in the adjusted pre-implant KCCQ-12 incompleteness rate was significantly associated with higher risk of infection (HR: 1.04).

CONCLUSIONS

Hospital adjusted pre-implant HRQOL incompleteness was predictive of 90-day post-implant outcomes and may serve as a novel quality metric.

Health-related quality of life after restrictive versus liberal RBC transfusion for cardiac surgery: Sub-study from a randomized clinical trial

BACKGROUND

Transfusion Requirements in Cardiac Surgery III (TRICS III), a multi-center randomized controlled trial, demonstrated clinical non-inferiority for restrictive versus liberal RBC transfusion for patients undergoing cardiac surgery. However, it is uncertain if transfusion strategy affects long-term health-related quality of life (HRQOL).

STUDY DESIGN AND METHODS

In this planned sub-study of Australian patients in TRICS III, we sought to determine the non-inferiority of restrictive versus liberal transfusion strategy on long-term HRQOL and to describe clinical outcomes 24 months postoperatively. The restrictive strategy involved transfusing RBCs when hemoglobin was <7.5 g/dl; the transfusion triggers in the liberal group were: <9.5 g/L intraoperatively, <9.5 g/L in intensive care, or <8.5 g/dl on the ward. HRQOL assessments were performed using the 36-item short form survey version 2 (SF-36v2). Primary outcome was non-inferiority of summary measures of SF-36v2 at 12 months, (non-inferiority margin: -0.25 effect size; restrictive minus liberal scores). Secondary outcomes included non-inferiority of HRQOL at 18 and 24 months.

RESULTS

Six hundred seventeen Australian patients received allocated randomization; HRQOL data were available for 208/311 in restrictive and 217/306 in liberal group. After multiple imputation, non-inferiority of restrictive transfusion at 12 months was not demonstrated for HRQOL, and the estimates were directionally in favor of liberal transfusion. Non-inferiority also could not be concluded at 18 and 24 months. Sensitivity analyses supported these results. There were no differences in quality-adjusted life years or composite clinical outcomes up to 24 months after surgery.

DISCUSSION

The non-inferiority of a restrictive compared to a liberal transfusion strategy was not established for long-term HRQOL in this dataset.

What difference does multiple imputation make in longitudinal modeling of EQ-5D-5L data? Empirical analyses of simulated and observed missing data patterns

PURPOSE

Although multiple imputation is the state-of-the-art method for managing missing data, mixed models without multiple imputation may be equally valid for longitudinal data. Additionally, it is not clear whether missing values in multi-item instruments should be imputed at item or score-level. We therefore explored the differences in analyzing the scores of a health-related quality of life questionnaire (EQ-5D-5L) using four approaches in two empirical datasets.

METHODS

We used simulated (GR dataset) and observed missingness patterns (ABCD dataset) in EQ-5D-5L scores to investigate the following approaches: approach-1) mixed models using respondents with complete cases, approach-2) mixed models using all available data, approach-3) mixed models after multiple imputation of the EQ-5D-5L scores, and approach-4) mixed models after multiple imputation of EQ-5D 5L items.

RESULTS

Approach-1 yielded the highest estimates of all approaches (ABCD, GR), increasingly overestimating the EQ-5D-5L score with higher percentages of missing data (GR). Approach-4 produced the lowest scores at follow-up evaluations (ABCD, GR). Standard errors (0.006-0.008) and mean squared errors (0.032-0.035) increased with increasing percentages of simulated missing GR data. Approaches 2 and 3 showed similar results (both datasets).

CONCLUSION

Complete cases analyses overestimated the scores and mixed models after multiple imputation by items yielded the lowest scores. As there was no loss of accuracy, mixed models without multiple imputation, when baseline covariates are complete, might be the most parsimonious choice to deal with missing data. However, multiple imputation may be needed when baseline covariates are missing and/or more than two timepoints are considered.

Sex Differences in Recovery and Device Replacement After Left Ventricular Assist Device Implantation as Destination Therapy

Background The relevance of sex and preimplant factors for clinical outcomes among patients with left ventricular assist devices intended for destination therapy is unclear. Methods and Results INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) data (2006-2017) from 6771 men and 1690 women with left ventricular assist devices as destination therapy were analyzed to evaluate the contribution of preimplant clinical, demographic, and clinically judged psychosocial characteristics to time until death, heart transplant, device explant due to recovery, or complication-related device replacement. Associations of sex with time until each competing outcome were evaluated using cumulative incidence functions and event-specific Cox proportional hazards models. Women were younger, more likely to have nonischemic diagnoses, and reported less substance abuse but were more likely to be unmarried, not working for an income, overweight, and depressed than men. After 2 years, women had higher probabilities for recovery (3.7% versus 1.6%, P<0.001) and device replacement (12.1% versus 10%, P=0.019) than men but not for death and transplant (P>0.12). The sex differences remained after controlling for covariates (adjusted hazard ratio [HR_adj] recovery, 1.85; 95% CI, 1.30-2.70; P<0.001; HR_adj device replacement, 1.22; 95% CI, 1.04-1.33; P=0.015). Female-specific diagnoses (eg, postpartum heart failure) contributed to women's enhanced rate of recovery. Demographic and psychosocial factors were unrelated to women's increased event rates. Conclusions In destination therapy, women have higher rates of device replacement and recovery than men. The latter was partly explained by female-specific diagnoses. Standardized assessments of psychosocial characteristics are needed to elucidate their association with sex differences in outcomes.

Information Patients With Melanoma Spontaneously Report About Health-Related Quality of Life on Web-Based Forums: Case Study

Background

There is a general agreement on the importance of health-related quality of life (HRQoL). This type of information is becoming increasingly important for the value assessment of health technology assessment agencies in evaluating the benefits of new health technologies, including medicines. However, HRQoL data are often limited, and additional sources that provide this type of information may be helpful.

Objective

We aim to identify the HRQoL topics important to patients with melanoma based on web-based discussions on public social media forums.

Methods

We identified 3 public web-based forums from the United States and the United Kingdom, namely the Melanoma Patient Information Page, the Melanoma International Forum, and MacMillan. Their posts were randomly selected and coded using qualitative methods until saturation was reached.

Results

Of the posts assessed, 36.7% (150/409) of posts on Melanoma International Forum, 45.1% (198/439) on MacMillan, and 35.4% (128/362) on Melanoma Patient Information Page focused on HRQoL. The 2 themes most frequently mentioned were mental health and (un)certainty. The themes were constructed based on underlying and more detailed codes. Codes related to fear, worry and anxiety, uncertainty, and unfavorable effects were the most-often discussed ones.

Conclusions

Web-based forums are a valuable source for identifying relevant HRQoL aspects in patients with a given disease. These aspects could be cross-referenced with existing tools and they might improve the content validity of patient-reported outcome measures, including HRQoL questionnaires. In addition, web-based forums may provide health technology assessment agencies with a more holistic understanding of the external aspects affecting patient HRQoL. These aspects might support the value assessment of new health technologies and could therefore help inform topic prioritization as well as the scoping phase before any value assessment.

Gender differences in psychosocial and clinical characteristics in the European Registry for Patients with Mechanical Circulatory Support

BACKGROUND

Not much is known about psychosocial characteristics of men and women receiving continuous flow left ventricular assist devices (CF LVAD).

OBJECTIVE

To investigate gender differences in clinical and psychosocial (demographic, behavioral, psychological) characteristics in CF LVAD recipients.

METHODS

We analyzed European Registry for Patients with Mechanical Circulatory Support (EUROMACS) data (N=2395, 16.8% women; 2011 to 2017) and compared pre-implant characteristics in men and women intended for bridge-to-transplant (BTT) or destination therapy (DT).

RESULTS

Women were underrepresented [DT (n=61): 13.4%; BTT (n=341): 17.6%]. They were more likely to be divorced/separated, widowed, in unstable clinical condition, and non-working (DT only), but less likely to be smokers, to have ischemic cardiomyopathy or diabetes, and younger (BTT only) than men. Missing data were abundant, especially those that reflect psychological characteristics (>87%).

CONCLUSION

Gender differences were noted, some specific to device strategy. Improved collection of psychosocial characteristics is warranted to elucidate their relationship to future prognosis.

A longitudinal comparison of health-related quality of life in rural and urban recipients of left ventricular assist devices

Left ventricular assist devices (LVAD) are a common treatment for advanced heart failure (HF) to improve ventricular function, symptoms, and health-related quality of life (HRQOL). Many LVAD recipients travel long distances from rural areas for LVAD implantation and follow-up care. Individuals with HF in rural settings who have not undergone LVAD implantation have reported poor HRQOL. However, to date, no studies have compared HF-specific or generic HRQOL in rural and urban LVAD recipients. The purpose of this study was to compare generic and HF-specific HRQOL longitudinally from preimplantation to 1-, 3-, and 6- months postimplant in a cohort of rural and urban LVAD recipients (n = 95; rural n = 32 and urban n = 63). We measured generic HRQOL using the European Quality of Life Visual Analog Scale and HF-specific HRQOL with the quality of life domain of the Kansas City Cardiomyopathy Questionnaire (KCCQ). Latent growth curve modeling identified two phases of change in generic and HF-specific HRQOL: the initial response to LVAD between preimplantation and 1-month postimplant and the subsequent change between 1- and 6-months postimplant. Comparable improvements in generic HRQOL were noted in rural and urban LVAD recipients during both phases of change. Urban LVAD recipients had greater initial improvements in HF-specific HRQOL (KCCQ) compared with rural recipients (13.0 ± 5.6, p = .02), but subsequent improvements were similar among rural and urban recipients. Ongoing assessment of generic and HF-specific HRQOL is necessary during LVAD therapy.

Trajectories of health-related quality of life among renal transplant patients associated with graft failure and symptom distress: Analysis of the BENEFIT and BENEFIT-EXT trials

Understanding the correlation between transplant symptoms, health-related quality of life (HRQoL), and graft outcomes is needed to support patient-focused drug development and posttransplant management. A post-hoc analysis of patient-reported outcomes from the Phase III belatacept trials was conducted in order to investigate the interrelationship between trajectories of HRQoL, symptom experience, and allograft outcomes. HRQoL and symptom experience were evaluated using Short-Form 36 Survey (SF-36) and Modified Transplant Symptom Occurrence and Distress Scale (MTSOSD-59R), respectively. HRQoL was captured in 831 eligible renal transplant patients at baseline, 12, 24, and 36 months posttransplant. Following transplantation, patients reported improvements in all SF-36 subscales compared to baseline. Latent class analysis revealed four trajectories in perceived general health, which were associated with graft failure after adjustment. Compared to patients with good perceived health, patients with fair and poor perceived health had 4.7 (95% confidence interval [CI] 1.5-14.8, P < .01) and 19.8 (95% CI 5.9-66.0, P < .01) times the risk of graft failure, respectively. Using multinomial logistic regression, different sets of symptoms were associated with perceived general health at baseline and 12 months posttransplant. The study supports monitoring HRQoL and symptom experience to capture each patient's health perspective, improve drug development, and optimize posttransplant management.

Integrating Quality of Life and Survival Outcomes in Cardiovascular Clinical Trials

Background Survival and health status (eg, symptoms and quality of life) are key outcomes in clinical trials of heart failure treatment. However, health status can only be recorded on survivors, potentially biasing treatment effect estimates when there is differential survival across treatment groups. Joint modeling of survival and health status can address this bias. Methods and Results We analyzed patient-level data from the PARTNER 1B trial (Placement of Aortic Transcatheter Valves) of transcatheter aortic valve replacement versus standard care. Health status was quantified with the Kansas City Cardiomyopathy Questionnaire (KCCQ) at randomization, 1, 6, and 12 months. We compared hazard ratios for survival and mean differences in KCCQ scores at 12 months using several models: the original growth curve model for KCCQ scores (ignoring death), separate Bayesian models for survival and KCCQ scores, and a Bayesian joint longitudinal-survival model fit to either 12 or 30 months of survival follow-up. The benefit of transcatheter aortic valve replacement on 12-month KCCQ scores was greatest in the joint-model fit to all survival data (mean difference, 33.7 points; 95% credible intervals [CrI], 24.2-42.4), followed by the joint-model fit to 12 months of survival follow-up (32.3 points; 95% CrI, 22.5-41.5), a Bayesian model without integrating death (30.4 points; 95% CrI, 21.4-39.3), and the original growth curve model (26.0 points; 95% CI, 18.7-33.3). At 12 months, the survival benefit of transcatheter aortic valve replacement was also greater in the joint model (hazard ratio, 0.50; 95% CrI, 0.32-0.73) than in the nonjoint Bayesian model (0.54; 95% CrI, 0.37-0.75) or the original Kaplan-Meier estimate (0.55; 95% CI, 0.40-0.74). Conclusions In patients with severe symptomatic aortic stenosis and prohibitive surgical risk, the estimated benefits of transcatheter aortic valve replacement on survival and health status compared with standard care were greater in joint Bayesian models than other approaches.