A systematic review and critical assessment of health state utilities: weight change and type 2 diabetes mellitus

The development of a core outcomes set for self-management interventions for patients living with obesity

Self-management interventions (SMIs) can improve the life of patients living with obesity. However, there is variability in the outcomes used to assess the effectiveness of SMIs and these are often not relevant for patients. In the context of COMPAR-EU, our aim was to develop a core outcome set (COS) for the evaluation of SMIs for patients with obesity. We followed a four steps multimethod approach: (1) the development of the initial catalogue of outcomes; (2) a scoping review of reviews on patients' values and preferences on outcomes of self-management (SM); (3) a Delphi survey including patients and patient representatives to rate the importance of outcomes; and (4) a 2-day consensus workshop with patients, patient representatives, healthcare professionals and researchers. The initial catalogue included 82 outcomes. Ten patients and patient's representatives participated in the Delphi survey. We identified 16 themes through the thematic synthesis of the scoping review that informed 37.80% of the outcomes on initial catalogue. Five patients, five healthcare professionals, and four researchers participated in the consensus workshop. After the consensus process, 15 outcomes were selected to be part of the final COS, and five supplementary outcomes were also provided. We developed a COS for the evaluation of SMIs in obesity with a significant involvement of patients and other key stakeholders. This COS will help improving data synthesis and increasing the value of SM research data in healthcare decision making.

The Perspectives of Patients with Chronic Diseases and Their Caregivers on Self-Management Interventions: A Scoping Review of Reviews

BACKGROUND

Self-management (SM) interventions are supportive interventions systematically provided by healthcare professionals, peers, or laypersons to increase the skills and confidence of patients in their ability to manage chronic diseases. We had two objectives: (1) to summarise the preferences and experiences of patients and their caregivers (informal caregivers and healthcare professionals) with SM in four chronic diseases and (2) to identify and describe the relevant outcomes for SM interventions from these perspectives.

METHODS

We conducted a mixed-methods scoping review of reviews. We searched three databases until December 2020 for quantitative, qualitative, or mixed-methods reviews exploring patients' and caregivers' preferences or experiences with SM in type 2 diabetes mellitus (T2DM), obesity, chronic obstructive pulmonary disease (COPD), and heart failure (HF). Quantitative data were narratively synthesised, and qualitative data followed a three-step descriptive thematic synthesis. Identified themes were categorised into outcomes or modifiable factors of SM interventions.

RESULTS

We included 148 reviews covering T2DM (n = 53 [35.8%]), obesity (n = 20 [13.5%]), COPD (n = 32 [21.6%]), HF (n = 38 [25.7%]), and those with more than one disease (n = 5 [3.4%]). We identified 12 main themes. Eight described the process of SM (disease progression, SM behaviours, social support, interaction with healthcare professionals, access to healthcare, costs for patients, culturally defined roles and perceptions, and health knowledge), and four described their experiences with SM interventions (the perceived benefit of the intervention, individualised care, sense of community with peers, and usability of equipment). Most themes and subthemes were categorised as outcomes of SM interventions.

CONCLUSION

The process of SM shaped the perspectives of patients and their caregivers on SM interventions. Their perspectives were influenced by the perceived benefit of the intervention, the sense of community with peers, the intervention's usability, and the level of individualised care. Our findings can inform the selection of patient-important outcomes, decision-making processes, including the formulation of recommendations, and the design and implementation of SM interventions.

Utility Decrements Associated with Adult Overweight and Obesity in Australia: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim was to conduct a systematic review and meta-analysis of health state utility decrements associated with overweight and obesity in adults 18 years and over, for use in modelled economic evaluations in Australia.

METHODS

A systematic review was conducted in nine databases to identify studies that reported health state utility values by weight status. Random-effects meta-analysis was used to synthesise average utility decrements (from healthy weight) associated with overweight, all obesity and obesity classes 1, 2 and 3. Heterogeneity surrounding utility decrements was assessed via sub-group analysis, random-effects meta-regression and sensitivity analyses.

RESULTS

Twelve studies were found for which data were used to synthesise utility decrements, estimated as overweight = 0.020 (95% confidence interval 0.010-0.030), all obesity = 0.055 (0.034-0.076), obesity class 1 = 0.047 (0.017-0.077), class 2 = 0.072 (0.028-0.116) and class 3 = 0.084 (0.039-0.130). There was considerable heterogeneity in our results, which could be accounted for by the different ages and utility instruments used in the contributing studies.

CONCLUSIONS

Our results demonstrate that elevated weight status is associated with small but statistically significant reductions in utility compared with healthy weight, which will result in reduced quality-adjusted life years when extrapolated across time and used in economic evaluations.

Toward a Centralized, Systematic Approach to the Identification, Appraisal, and Use of Health State Utility Values for Reimbursement Decision Making: Introducing the Health Utility Book (HUB)

Cost-utility analysis (CUA) is a widely recommended form of health economic evaluation worldwide. The outcome measure in CUA is quality-adjusted life-years (QALYs), which are calculated using health state utility values (HSUVs) and corresponding life-years. Therefore, HSUVs play a significant role in determining cost-effectiveness. Formal adoption and endorsement of CUAs by reimbursement authorities motivates methodological advancement in HSUV measurement and application. A large body of evidence exploring various methods in measuring HSUVs has accumulated, imposing challenges for investigators in identifying and applying HSUVs to CUAs. First, large variations in HSUVs between studies are often reported, and these may lead to different cost-effectiveness conclusions. Second, issues concerning the quality of studies that generate HSUVs are increasingly highlighted in the literature. This issue is compounded by the limited published guidance and methodological standards for assessing the quality of these studies. Third, reimbursement decision making is a context-specific process. Therefore, while an HSUV study may be of high quality, it is not necessarily appropriate for use in all reimbursement jurisdictions. To address these issues, by promoting a systematic approach to study identification, critical appraisal, and appropriate use, we are developing the Health Utility Book (HUB). The HUB consists of an HSUV registry, a quality assessment tool for health utility studies, and a checklist for interpreting their use in CUAs. We anticipate that the HUB will make a timely and important contribution to the rigorous conduct and proper use of health utility studies for reimbursement decision making. In this way, health care resource allocation informed by HSUVs may reflect the preferences of the public, improve health outcomes of patients, and maintain the efficiency of health care systems.

Utility values for childhood obesity interventions: a systematic review and meta-analysis of the evidence for use in economic evaluation

Rigorous estimates of preference-based utilities are important inputs into economic evaluations of childhood obesity interventions, yet no published review currently exists examining utility by weight status in paediatric populations. A comprehensive systematic literature review and meta-analysis was therefore undertaken, pooling data on preference-based health state utilities by weight status in children using a random-effects model. Tests for heterogeneity were performed, and publication bias was assessed. Of 3,434 potentially relevant studies identified, 11 met our eligibility criteria. Estimates of Cohen's d statistic suggested a small effect of weight status on preference-based utilities. Mean utility values were estimated as 0.85 (95% uncertainty interval [UI] 0.84-0.87), 0.83 (95% UI 0.81-0.85), 0.82 (95% UI 0.79-0.84) and 0.83 (95% UI 0.80-0.86) for healthy weight, overweight, obese and overweight/obese states, respectively. Meta-analysis of studies reporting utility values for both healthy weight and overweight/obese participants found a statistically significant weighted mean difference (0.015, 95% UI 0.003-0.026). A small but statistically significant difference was also estimated between healthy weight and overweight participants (0.011, 95% UI 0.004-0.018). Study findings suggest that paediatric-specific benefits of obesity interventions may not be well reflected by available utility measures, potentially underestimating cost-effectiveness if weight loss in childhood/adolescence improves health or well-being.

Health-related quality of life and health preference of Chinese patients with diabetes mellitus managed in primary care and secondary care setting: decrements associated with individual complication and number of complications

Background

Health-related quality of life (HRQoL) and health preference of patients with diabetes mellitus (DM) are essential in health economic evaluations but data on Chinese population is rare. This study aims to evaluate HRQoL and health preference of diabetic patients with different diabetic complications in Chinese population.

Methods

A cross-sectional study was conducted in 1275 patients with DM, including 518 subjects with various DM-related complications. HRQoL and health preference were estimated using SF-12 and SF-6D questionnaires, respectively. Disease status of DM and complications were identified from documented clinical diagnosis. Multivariable regression was used to investigate the effects of specific complications on HRQoL and health preference, adjusting for socio-demographic and clinical parameters.

Results

The presence of any diabetic complication was associated with lower physical component summary (−3.81 points, P < 0.01), and end-stage renal disease (ESRD) showed greatest reduction (−7.05 points, P < 0.01). Mental component summary and mental health (MH) scores were not decreased in any of the diabetic complications. The health preference score for diabetic subjects without complications was 0.882 (95% CI, 0.778 to 0.989). The reductions of health preference score were significant for stroke (−0.042, 95% CI -0.072 to −0.012), ESRD (−0.055, 95% CI -0.093 to −0.017), and sight-threatening diabetic retinopathy (STDR) (−0.043, 95% CI -0.075 to −0.010), while heart disease had an insignificant reduction (−0.017, 95% CI -0.042 to 0.008).

Conclusions

The presence of any of the four major diabetic complications (heart disease, stroke, ESRD and STDR) was associated with lower HRQoL and health preference scores. Findings of this study facilitated the cost-effectiveness studies of alternative management strategies for prevention of diabetic complications in Chinese population.

Electronic supplementary material

The online version of this article (doi:10.1186/s12955-017-0699-4) contains supplementary material, which is available to authorized users.

Health state utility values for diabetic retinopathy: protocol for a systematic review and meta-analysis

BACKGROUND

People with diabetic retinopathy tend to have lower levels of health-related quality of life than individuals with no retinopathy. Strategies for screening and treatment have been shown to be cost-effective. In order to reduce the bias in cost-effectiveness estimates, systematic reviews of health state utility values (HSUVs) are crucial for health technology assessment and the development of decision analytic models. A review and synthesis of HSUVs for the different stages of disease progression in diabetic retinopathy has not previously been conducted.

METHODS/DESIGN

We will conduct a systematic review of the available literature that reports HSUVs for people with diabetic retinopathy, in correspondence with current stage of disease progression and/or visual acuity. We will search Medline, EMBASE, Web of Science, Cost-Effectiveness Analysis Registry, Centre for Reviews and Dissemination Database, and EconLit to identify relevant English-language articles. Data will subsequently be synthesized using linear mixed effects modeling meta-regression. Additionally, reported disease severity classifications will be mapped to a four-level grading scale for diabetic retinopathy.

DISCUSSION

The systematic review and meta-analysis will provide important evidence for future model-based economic evaluations of technologies for diabetic retinopathy. The meta-regression will enable the estimation of utility values at different disease stages for patients with particular characteristics and will also highlight where the design of the study and HSUV instrument have influenced the reported utility values. We believe this protocol to be the first of its kind to be published.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42014012891.

The impact of weight loss on health-related quality-of-life: implications for cost-effectiveness analyses

PURPOSE

To assess the impact of weight loss on health-related quality-of-life (HRQL), to describe the factors associated with improvements in HRQL after weight loss, and to assess the relationship between obesity as assessed by body mass index (BMI) and HRQL before and after weight loss.

METHODS

We studied 188 obese patients with BMI ≥ 32 kg/m(2) with one or more comorbidities or ≥35 kg/m(2). All patients had baseline and follow-up assessments of BMI and HRQL using the EuroQol (EQ-5D) and its visual analog scale (VAS) before and after 6 months of medical weight loss that employed very low-calorie diets, physical activity, and intensive behavioral counseling.

RESULTS

At baseline, age was 50 ± 8 years (mean ± SD), BMI was 40. 0 ± 5.0 kg/m(2), EQ-5D-derived health utility score was 0.85 ± 0.13, and VAS-reported quality-of-life was 0.67 ± 0.18. At 6-month follow-up, BMI decreased by 7.0 ± 3.2 kg/m(2), EQ-5D increased by 0.06 [interquartile range (IQR) 0.06-0.17], and VAS increased by 0.14 (IQR 0.04-0.23). In multivariate analyses, improvement in EQ-5D and VAS were associated with lower baseline BMI, greater reduction in BMI at follow-up, fewer baseline comorbidities, and lower baseline HRQL. For any given BMI category, EQ-5D and VAS tended to be higher at follow-up than at baseline.

CONCLUSION

Measured improvements in HRQL between baseline and follow-up were greater than predicted by the reduction in BMI at follow-up. If investigators use cross-sectional data to estimate changes in HRQL as a function of BMI, they will underestimate the improvement in HRQL associated with weight loss and underestimate the cost-utility of interventions for obesity treatment.