A Systematic Review of Cost-Effectiveness Studies of Interventions With a Personalized Nutrition Component in Adults

OBJECTIVES

Important links between dietary patterns and diseases have been widely applied to establish nutrition interventions. However, knowledge about between-person heterogeneity regarding the benefits of nutrition intervention can be used to personalize the intervention and thereby improve health outcomes and efficiency. We performed a systematic review of cost-effectiveness analyses (CEAs) of interventions with a personalized nutrition (PN) component to assess their methodology and findings.

METHODS

A systematic search (March 2019) was performed in 5 databases: EMBASE, Medline Ovid, Web of Science, Cochrane CENTRAL, and Google Scholar. CEAs involving interventions in adults with a PN component were included; CEAs focusing on clinical nutrition or undernutrition were excluded. The CHEERS checklist was used to assess the quality of CEAs.

RESULTS

We identified 49 eligible studies among 1792 unique records. Substantial variation in methodology was found. Most studies (91%) focused only on psychological concepts of PN such as behavior and preferences. Thirty-four CEAs were trial-based, 13 were modeling studies, and 4 studies were both trial- and model-based. Thirty-two studies used quality-adjusted life year as an outcome measure. Different time horizons, comparators, and modeling assumptions were applied, leading to differences in costs/quality-adjusted life years. Twenty-eight CEAs (49%) concluded that the intervention was cost-effective, and 75% of the incremental cost-utility ratios were cost-effective given a willingness-to-pay threshold of $50 000 per quality-adjusted life year.

CONCLUSIONS

Interventions with PN components are often evaluated using various types of models. However, most PN interventions have been considered cost-effective. More studies should examine the cost-effectiveness of PN interventions that combine psychological and biological concepts of personalization.

Cost-utility analysis of lifestyle interventions to prevent type 2 diabetes in women with prior gestational diabetes

BACKGROUND

To compare estimated costs and health outcomes of lifestyle interventions for the prevention of type 2 diabetes mellitus in women who had gestational diabetes.

METHODS

An age-specific Markov model was applied comparing costs and quality-adjusted life years (QALYs) of three alternatives: 'doing nothing'; an annual reminder system (ARS) with an awareness campaign ('ARS-awareness'); and an ARS with an intensive lifestyle intervention ('ARS-ILS'). A healthcare payer perspective was adopted, the time horizon was 30 years and the setting was Flanders (Belgium). Sensitivity analyses were performed.

RESULTS

'ARS-awareness' was extendedly dominated. Per 10 000 participants, 'ARS-ILS' cost €13 210 256 more and gained 496 QALYs compared with 'doing nothing' (26 632 €/QALY), with a 63% probability of being cost effective, given a cost effectiveness threshold of 35 000 €/QALY. A scenario analysis showed that 'ARS-ILS' for 15 years only offered to women with prediabetes (compared with 'doing nothing') has an 89.5% likelihood of being dominant.

CONCLUSIONS

'ARS-ILS' may be the preferred intervention. However, the probability of being cost effective was low. Based on further scenario analyses, we recommend healthcare decision makers to consider the application of a more intensive alternative, focused on the highest risk profiles and with a shorter intervention duration.

A Systematic Review of Methods to Predict Weight Trajectories in Health Economic Models of Behavioral Weight-Management Programs: The Potential Role of Psychosocial Factors

Objectives. There is limited evidence on the long-term effectiveness of behavioral weight-management interventions, and thus, when conducting health economic modeling, assumptions are made about weight trajectories. The aims of this review were to examine these assumptions made about weight trajectories, the evidence sources used to justify them, and the impact of assumptions on estimated cost-effectiveness. Given the evidence that some psychosocial variables are associated with weight-loss trajectories, we also aimed to examine the extent to which psychosocial variables have been used to estimate weight trajectories and whether psychosocial variables were measured within cited evidence sources. Methods. A search of databases (Medline, PubMed, Cochrane, NHS Economic Evaluation, Embase, PSYCinfo, CINAHL, EconLit) was conducted using keywords related to overweight, weight-management, and economic evaluation. Economic evaluations of weight-management interventions that included modeling beyond trial data were included. Results. Within the 38 eligible articles, 6 types of assumptions were reported (weight loss maintained, weight loss regained immediately, linear weight regain, subgroup-specific trajectories, exponential decay of effect, maintenance followed by regain). Fifteen articles cited at least 1 evidence source to support the assumption reported. The assumption used affected the assessment of cost-effectiveness in 9 of the 19 studies that tested this in sensitivity analyses. None of the articles reported using psychosocial factors to estimate weight trajectories. However, psychosocial factors were measured in evidence sources cited by 11 health economic models. Conclusions. Given the range of weight trajectories reported and the potential impact on funding decisions, further research is warranted to investigate how psychosocial variables measured in trials can be used within health economic models to simulate heterogeneous weight trajectories and potentially improve the accuracy of cost-effectiveness estimates.

Health benefits and costs of weight-loss dietary counselling by nurses in primary care: a cost-effectiveness analysis

OBJECTIVE

We aimed to estimate the cost-effectiveness of brief weight-loss counselling by dietitian-trained practice nurses, in a high-income-country case study.

DESIGN

A literature search of the impact of dietary counselling on BMI was performed to source the 'best' effect size for use in modelling. This was combined with multiple other input parameters (e.g. epidemiological and cost parameters for obesity-related diseases, likely uptake of counselling) in an established multistate life-table model with fourteen parallel BMI-related disease life tables using a 3 % discount rate.

SETTING

New Zealand (NZ).

PARTICIPANTS

We calculated quality-adjusted life-years (QALY) gained and health-system costs over the remainder of the lifespan of the NZ population alive in 2011 (n 4·4 million).

RESULTS

Counselling was estimated to result in an increase of 250 QALY (95 % uncertainty interval -70, 560 QALY) over the population's lifetime. The incremental cost-effectiveness ratio was 2011 $NZ 138 200 per QALY gained (2018 $US 102 700). Per capita QALY gains were higher for Māori (Indigenous population) than for non-Māori, but were still not cost-effective. If willingness-to-pay was set to the level of gross domestic product per capita per QALY gained (i.e. 2011 $NZ 45 000 or 2018 $US 33 400), the probability that the intervention would be cost-effective was 2 %.

CONCLUSIONS

The study provides modelling-level evidence that brief dietary counselling for weight loss in primary care generates relatively small health gains at the population level and is unlikely to be cost-effective.

A systematic review on costs and cost-effectiveness of screening and prevention of type 2 diabetes in women with prior gestational diabetes: Exploring uncharted territory

AIMS

Women with gestational diabetes mellitus (GDM) are more likely to develop type 2 diabetes mellitus (T2DM) as compared to women with normoglycemic pregnancies. This study aims to explore the literature on cost(-effectiveness) of screening and prevention of T2DM in women with prior GDM.

METHODS

Five databases were systematically searched, inclusion criteria were: (1) women with (prior) GDM; (2) post-partum screening or prevention of T2DM; and (3) health-economic evaluations. No year limits were applied. English, Dutch, French or German publications were included. Quality was assessed using the Consensus Health Economic Criteria checklist.

RESULTS

Two cost-effectiveness analyses and two cost analyses were found. One study evaluated nine screening strategies. Three studies evaluated one prevention strategy each: intensive diet and behavioural modification; annual counseling; and an annual dietary consultation. Methodological quality was poor. Perspectives were unclear, time horizons were too short, and no incremental analyses were performed.

CONCLUSION

An oral glucose tolerance test per three years leads to the lowest cost per case detected, and prevention is potentially cost-effective or cost-saving. More health economic evaluations are needed that compare all relevant alternatives, including 'doing nothing'.

Quality and future of clinical laboratories: the Vico’s whole cyclical theory of the recurring cycles

In the last few decades, laboratory medicine has undergone monumental changes, and laboratory technology, which has made enormous advances, now has new clinical applications thanks to the identification of a growing number of biomarkers and risk factors conducive to the promotion of predictive and preventive interventions that have enhanced the role of laboratory medicine in health care delivering. However, the paradigm shift in the past 50 years has led to a gap between laboratory and clinic, with an increased risk of inappropriateness in test request and interpretation, as well as the consolidation of analytical work in focused factories and megastructurers oriented only toward achieving greater volumes, decreasing cost per test and generating a vision of laboratory services as simple commodities. A careful historical revision of the changing models for delivering laboratory services in the United States leads to the prediction that there are several reasons for counteracting the vision of clinical laboratory as a commodity, and restoring the true nature of laboratory services as an integral part of the diagnosis and therapy process. The present study, which reports on internal and external drivers for change, proposes an integrated vision of quality in laboratory medicine.

Cost-effectiveness of population-based, community, workplace and individual policies for diabetes prevention in the UK

AIM

To analyse the cost-effectiveness of different interventions for Type 2 diabetes prevention within a common framework.

METHODS

A micro-simulation model was developed to evaluate the cost-effectiveness of a range of diabetes prevention interventions including: (1) soft drinks taxation; (2) retail policy in socially deprived areas; (3) workplace intervention; (4) community-based intervention; and (5) screening and intensive lifestyle intervention in individuals with high diabetes risk. Within the model, individuals follow metabolic trajectories (for BMI, cholesterol, systolic blood pressure and glycaemia); individuals may develop diabetes, and some may exhibit complications of diabetes and related disorders, including cardiovascular disease, and eventually die. Lifetime healthcare costs, employment costs and quality-adjusted life-years are collected for each person.

RESULTS

All interventions generate more life-years and lifetime quality-adjusted life-years and reduce healthcare spending compared with doing nothing. Screening and intensive lifestyle intervention generates greatest lifetime net benefit (£37) but is costly to implement. In comparison, soft drinks taxation or retail policy generate lower net benefit (£11 and £11) but are cost-saving in a shorter time period, preferentially benefit individuals from deprived backgrounds and reduce employer costs.

CONCLUSION

The model enables a wide range of diabetes prevention interventions to be evaluated according to cost-effectiveness, employment and equity impacts over the short and long term, allowing decision-makers to prioritize policies that maximize the expected benefits, as well as fulfilling other policy targets, such as addressing social inequalities.

Economic Evaluation of Combined Diet and Physical Activity Promotion Programs to Prevent Type 2 Diabetes Among Persons at Increased Risk: A Systematic Review for the Community Preventive Services Task Force

BACKGROUND

Diabetes is a highly prevalent and costly disease. Studies indicate that combined diet and physical activity promotion programs can prevent type 2 diabetes among persons at increased risk.

PURPOSE

To systematically evaluate the evidence on cost, cost-effectiveness, and cost-benefit estimates of diet and physical activity promotion programs.

DATA SOURCES

Cochrane Library, EMBASE, MEDLINE, PsycINFO, Sociological Abstracts, Web of Science, EconLit, and CINAHL through 7 April 2015.

STUDY SELECTION

English-language studies from high-income countries that provided data on cost, cost-effectiveness, or cost-benefit ratios of diet and physical activity promotion programs with at least 2 sessions over at least 3 months delivered to persons at increased risk for type 2 diabetes.

DATA EXTRACTION

Dual abstraction and assessment of relevant study details.

DATA SYNTHESIS

Twenty-eight studies were included. Costs were expressed in 2013 U.S. dollars. The median program cost per participant was $653. Costs were lower for group-based programs (median, $417) and programs implemented in community or primary care settings (median, $424) than for the U.S. DPP (Diabetes Prevention Program) trial and the DPP Outcomes Study ($5881). Twenty-two studies assessed the incremental cost-effectiveness ratios (ICERs) of the programs. From a health system perspective, 16 studies reported a median ICER of $13 761 per quality-adjusted life-year (QALY) saved. Group-based programs were more cost-effective (median, $1819 per QALY) than those that used individual sessions (median, $15 846 per QALY). No cost-benefit studies were identified.

LIMITATION

Information on recruitment costs and cost-effectiveness of translational programs implemented in community and primary care settings was limited.

CONCLUSION

Diet and physical activity promotion programs to prevent type 2 diabetes are cost-effective among persons at increased risk. Costs are lower when programs are delivered to groups in community or primary care settings.

PRIMARY FUNDING SOURCE

None.

A systematic review of the cost-effectiveness of non-surgical obesity interventions in men

BACKGROUND

Increasing obesity related health conditions have a substantial burden on population health and healthcare spending. Obesity may have a sex-specific impact on disease development, men and women may respond differently to interventions, and there may be sex-specific differences to the cost-effectiveness of interventions to address obesity. There is no clear indication of cost-effective treatments for men.

METHODS

This systematic review summarises the literature reporting the cost-effectiveness of non-surgical weight-management interventions for men. Studies were quality assessed against a checklist for appraising decision modelling studies.

RESULTS

Although none of the included studies explicitly set out to determine the cost-effectiveness of treatment for men, seven studies reported results for subgroups of men. Interventions were grouped into lifestyle interventions (five studies) and Orlistat (two studies). The retrieved studies showed promising evidence of cost-effectiveness, especially when interventions were targeted at high-risk groups, such as those with impaired glucose tolerance. There appears to be some sex-specific elements to cost-effectiveness, however, there were no clear trends or indications of what may be contributing to this.

CONCLUSION

The economic evidence was highly uncertain, and limited by variable methodological quality of the included studies. It was therefore not possible to draw strong conclusions on cost-effectiveness. Future studies are required to demonstrate the cost-effectiveness of interventions specifically targeted towards weight loss for men.

Prioritising prevention: implementation of IGT Care Call, a telephone based service for people at risk of developing type 2 diabetes

AIM

To design, deliver and evaluate IGT Care Call, a telephone service providing a 6 month lifestyle education programme for people with impaired glucose tolerance (IGT).

METHODS

An observational study of IGT Care Call, a programme providing motivational support and education using electronic scripts. The service was delivered to 55 participants, all of whom completed the course (an information pack and at least five telephone calls over 6 months). Clinical measurements were undertaken in General Practice at baseline, on completion of the programme and one year later.

RESULTS

Among the 40 participants for whom we have complete data available, one year after discharge, participants showed improvements in fasting plasma glucose (0.29 mmol/l, 95% CI 0.07 to 0.51), weight (2.81 kg, 95% CI 1.20 to 4.42) and BMI (1.06 kg/m(2), 95% CI 0.49 to 1.63). All differences were statistically significant (p < 0.01).

CONCLUSION

Whilst an uncontrolled observational study with a small sample size, this pilot suggests IGT Care Call may be effective in promoting positive and sustained lifestyle changes to prevent type 2 diabetes, which warrants further investigation. A telephone method of service delivery was acceptable, convenient and may have improved self confidence in how to reduce risk of type 2 diabetes.

Modelling the economics of type 2 diabetes mellitus prevention: a literature review of methods

Our objective was to review modelling methods for type 2 diabetes mellitus prevention cost-effectiveness studies. The review was conducted to inform the design of a policy analysis model capable of assisting resource allocation decisions across a spectrum of prevention strategies. We identified recent systematic reviews of economic evaluations in diabetes prevention and management of obesity. We extracted studies from two existing systematic reviews of economic evaluations for the prevention of diabetes. We extracted studies evaluating interventions in a non-diabetic population with type 2 diabetes as a modelled outcome, from two systematic reviews of obesity intervention economic evaluations. Databases were searched for studies published between 2008 and 2013. For each study, we reviewed details of the model type, structure, and methods for predicting diabetes and cardiovascular disease. Our review identified 46 articles and found variation in modelling approaches for cost-effectiveness evaluations for the prevention of type 2 diabetes. Investigation of the variables used to estimate the risk of type 2 diabetes suggested that impaired glucose regulation, and body mass index were used as the primary risk factors for type 2 diabetes. A minority of cost-effectiveness models for diabetes prevention accounted for the multivariate impacts of interventions on risk factors for type 2 diabetes. Twenty-eight cost-effectiveness models included cardiovascular events in addition to type 2 diabetes. Few cost-effectiveness models have flexibility to evaluate different intervention types. We conclude that to compare a range of prevention interventions it is necessary to incorporate multiple risk factors for diabetes, diabetes-related complications and obesity-related co-morbidity outcomes.

Behaviour change among people with impaired glucose tolerance: Comparison of telephone-based and face-to-face advice

Objectives

To develop, implement and compare two lifestyle services for people at risk of developing type 2 diabetes.

Methods

Two localities were selected to implement two different service delivery models, telephone-based and face-to-face, supporting people at risk of developing type 2 diabetes. Impact was assessed by comparing weight, fasting plasma glucose and oral glucose tolerance test (OGTT) results at baseline and six months later.

Results

Both services were associated with an improvement in OGTT 2-h plasma glucose and weight. In the telephone intervention, 47.3% of participants who completed the project achieved both normal fasting plasma glucose (≤6.0 mmol/l) and normal plasma glucose levels (≤7.7 mmol/l). Participants had a mean weight loss of 3.3 kg ( SD 4.3), equating to 3.4% of body weight ( p < 0.001). In the face-to-face intervention, 46.3% of participants achieved normal plasma glucose (≤7.7 mmol/l) and a mean weight loss of 2.9 kg ( SD 4.5), equating to 3.1% of bodyweight ( p < 0.001).

Conclusions

Local health providers can adapt existing service provision and tailor it to provide lifestyle programmes for people with impaired glucose tolerance. Both service delivery models offer effective diabetes prevention although each model may cater for different population needs and a choice of services might be the preferred option.

Cost and clinical implications of diabetes prevention in an Australian setting: a long-term modeling analysis

AIMS/HYPOTHESIS

Metformin and intensive lifestyle changes (ILC) reduced the incidence of type 2 diabetes (T2D) versus standard care (control) in overweight or obese subjects with impaired glucose tolerance (IGT) in the Diabetes Prevention Program (DPP) trial and Diabetes Prevention Program Outcomes Study (DPPOS). We projected lifetime clinical and economic outcomes based on the results from the DPP+DPPOS, from a 3rd-party payer perspective in Australia.

METHODS

A semi-Markov, 2nd-order Monte Carlo model was developed with four health states: "normal glucose regulation" (NGR); IGT; T2D and 'dead'. Outcomes were discounted at 5% annually. Univariate and probabilistic sensitivity analyses were performed. Incremental cost-effectiveness ratios (ICERs) were calculated.

RESULTS

Cumulative incidence (standard deviation) of T2D was 89.7% (0.2), 83.8% (0.2) and 73.4% (0.3%) for control, metformin and ILC respectively. Lifetime incremental direct costs were $1217 (4411) per subject for metformin versus control, with cost savings of $289 (4296) for ILC versus control. ILC therefore dominated control, with improvements in clinical outcomes and overall cost savings. Incremental costs per QALY-gained for metformin versus control were $10,142. Probability of cost-effectiveness at willingness-to-pay threshold of $50,000 was 78% and 100% for metformin or ILC respectively. Results were most sensitive to probabilities of developing T2D and costs of implementing the interventions.

CONCLUSIONS/INTERPRETATION

Substantial improvements in lifetime clinical outcomes could be expected in high risk subjects treated with metformin or ILC. Prevention of T2D in this group of subjects is good value for money, and may even lead to long term cost savings.

Targeted versus universal prevention. a resource allocation model to prioritize cardiovascular prevention

BACKGROUND

Diabetes mellitus brings an increased risk for cardiovascular complications and patients profit from prevention. This prevention also suits the general population. The question arises what is a better strategy: target the general population or diabetes patients.

METHODS

A mathematical programming model was developed to calculate optimal allocations for the Dutch population of the following interventions: smoking cessation support, diet and exercise to reduce overweight, statins, and medication to reduce blood pressure. Outcomes were total lifetime health care costs and QALYs. Budget sizes were varied and the division of resources between the general population and diabetes patients was assessed.

RESULTS

Full implementation of all interventions resulted in a gain of 560,000 QALY at a cost of €640 per capita, about €12,900 per QALY on average. The large majority of these QALY gains could be obtained at incremental costs below €20,000 per QALY. Low or high budgets (below €9 or above €100 per capita) were predominantly spent in the general population. Moderate budgets were mostly spent in diabetes patients.

CONCLUSIONS

Major health gains can be realized efficiently by offering prevention to both the general and the diabetic population. However, a priori setting a specific distribution of resources is suboptimal. Resource allocation models allow accounting for capacity constraints and program size in addition to efficiency.

Cost-effectiveness of a lifestyle intervention in preventing Type 2 diabetes

OBJECTIVES

Previous research has suggested people with impaired fasting glucose (IFG) are less likely to develop Type 2 diabetes (T2DM) if they receive prolonged structured diet and exercise advice. This study examined the within-trial cost-effectiveness of such lifestyle interventions.

METHODS

Screen-detected participants with either newly diagnosed T2DM or IFG were randomized 2:1 to intervention versus control (usual care) between February and December 2009, in Norfolk (UK). The intervention consisted of group based education, physiotherapy and peer support sessions, plus telephone contacts from T2DM volunteers. We monitored healthcare resource use, intervention costs, and quality of life (EQ-5D). The incremental cost per quality-adjusted life-year (QALY) gain (incremental cost effectiveness ratio [ICER]), and cost effectiveness acceptability curves (CEAC) were estimated.

RESULTS

In total, 177 participants were recruited (118 intervention, 59 controls), with a mean follow-up of 7 months. Excluding screening and recruitment costs, the mean cost was estimated to be £551 per participant in the intervention arm, compared with £325 in the control arm. The QALY gains were -0.001 and -0.004, respectively. The intervention was estimated to have an ICER of £67,184 per QALY (16 percent probability of being cost-effective at the £20,000/QALY threshold). Cost-effectiveness estimates were more favorable for IFG participants and those with longer follow-up (≥ 4 months) (ICERs of £20,620 and £17,075 per QALY, respectively).

CONCLUSIONS

Group sessions to prevent T2DM were not estimated to be within current limits of cost-effectiveness. However, there was a large degree of uncertainty surrounding these estimates, suggesting the need for further research.

Screening for type 2 diabetes and dysglycemia

Type 2 diabetes mellitus (T2DM) and dysglycemia (impaired glucose tolerance and/or impaired fasting glucose) are increasingly contributing to the global burden of diseases. The authors reviewed the published literature to critically evaluate the evidence on screening for both conditions and to identify the gaps in current understanding. Acceptable, relatively simple, and accurate tools can be used to screen for both T2DM and dysglycemia. Lifestyle modification and/or medication (e.g., metformin) are cost-effective in reducing the incidence of T2DM. However, their application is not yet routine practice. It is unclear whether diabetes-prevention strategies, which influence cardiovascular risk favorably, will also prevent diabetic vascular complications. Cardioprotective therapies, which are cost-effective in preventing complications in conventionally diagnosed T2DM, can be used in screen-detected diabetes, but the magnitude of their effects is unknown. Economic modeling suggests that screening for both T2DM and dysglycemia may be cost-effective, although empirical data on tangible benefits in preventing complications or death are lacking. Screening for T2DM is psychologically unharmful, but the specific impact of attributing the label of dysglycemia remains uncertain. Addressing these gaps will inform the development of a screening policy for T2DM and dysglycemia within a holistic diabetes prevention and control framework combining secondary and high-risk primary prevention strategies.

Behavior matters

Behavior has a broad and central role in health. Behavioral interventions can be effectively used to prevent disease, improve management of existing disease, increase quality of life, and reduce healthcare costs. A summary is presented of evidence for these conclusions in cardiovascular disease/diabetes, cancer, and HIV/AIDS as well as with key risk factors: tobacco use, poor diet, physical inactivity, and excessive alcohol consumption. For each, documentation is made of (1) moderation of genetic and other fundamental biological influences by behaviors and social-environmental factors; (2) impacts of behaviors on health; (3) success of behavioral interventions in prevention; (4) disease management; (5) quality of life, and (6) improvements in the health of populations through behavioral health promotion programs. Evidence indicates the cost effectiveness and value of behavioral interventions, especially relative to other common health services as well as the value they add in terms of quality of life. Pertinent to clinicians and their patients as well as to health policy and population health, the benefits of behavioral interventions extend beyond impacts on a particular disease or risk factor. Rather, they include broad effects and benefits on prevention, disease management, and well-being across the life span. Among priorities for dissemination research, the application of behavioral approaches is challenged by diverse barriers, including socioeconomic barriers linked to health disparities. However, behavioral approaches including those emphasizing community and social influences appear to be useful in addressing such challenges. In sum, behavioral approaches should have a central place in prevention and health care of the 21st century.

The economics of diabetes prevention

In the United States, the costs associated with diabetes mellitus are increasing. Although people with diabetes comprise less than 6% of the US population, approximately 1 in 5 health care dollars is spent caring for people with diabetes. Healthy lifestyle interventions for the general population and intensive lifestyle and medication interventions for high-risk individuals present opportunities for diabetes prevention. This article describes the costs associated with glucose intolerance and diabetes, the effect of glucose intolerance and diabetes on the quality of life, and the cost-effectiveness of screening and primary prevention interventions for diabetes prevention.

Cost-effectiveness of interventions to prevent and control diabetes mellitus: a systematic review

OBJECTIVE

To synthesize the cost-effectiveness (CE) of interventions to prevent and control diabetes, its complications, and comorbidities.

RESEARCH DESIGN AND METHODS

We conducted a systematic review of literature on the CE of diabetes interventions recommended by the American Diabetes Association (ADA) and published between January 1985 and May 2008. We categorized the strength of evidence about the CE of an intervention as strong, supportive, or uncertain. CEs were classified as cost saving (more health benefit at a lower cost), very cost-effective (<or=$25,000 per life year gained [LYG] or quality-adjusted life year [QALY]), cost-effective ($25,001 to $50,000 per LYG or QALY), marginally cost-effective ($50,001 to $100,000 per LYG or QALY), or not cost-effective (>$100,000 per LYG or QALY). The CE classification of an intervention was reported separately by country setting (U.S. or other developed countries) if CE varied by where the intervention was implemented. Costs were measured in 2007 U.S. dollars.

RESULTS

Fifty-six studies from 20 countries met the inclusion criteria. A large majority of the ADA recommended interventions are cost-effective. We found strong evidence to classify the following interventions as cost saving or very cost-effective: (I) Cost saving- 1) ACE inhibitor (ACEI) therapy for intensive hypertension control compared with standard hypertension control; 2) ACEI or angiotensin receptor blocker (ARB) therapy to prevent end-stage renal disease (ESRD) compared with no ACEI or ARB treatment; 3) early irbesartan therapy (at the microalbuminuria stage) to prevent ESRD compared with later treatment (at the macroalbuminuria stage); 4) comprehensive foot care to prevent ulcers compared with usual care; 5) multi-component interventions for diabetic risk factor control and early detection of complications compared with conventional insulin therapy for persons with type 1 diabetes; and 6) multi-component interventions for diabetic risk factor control and early detection of complications compared with standard glycemic control for persons with type 2 diabetes. (II) Very cost-effective- 1) intensive lifestyle interventions to prevent type 2 diabetes among persons with impaired glucose tolerance compared with standard lifestyle recommendations; 2) universal opportunistic screening for undiagnosed type 2 diabetes in African Americans between 45 and 54 years old; 3) intensive glycemic control as implemented in the UK Prospective Diabetes Study in persons with newly diagnosed type 2 diabetes compared with conventional glycemic control; 4) statin therapy for secondary prevention of cardiovascular disease compared with no statin therapy; 5) counseling and treatment for smoking cessation compared with no counseling and treatment; 6) annual screening for diabetic retinopathy and ensuing treatment in persons with type 1 diabetes compared with no screening; 7) annual screening for diabetic retinopathy and ensuing treatment in persons with type 2 diabetes compared with no screening; and 8) immediate vitrectomy to treat diabetic retinopathy compared with deferred vitrectomy.

CONCLUSIONS

Many interventions intended to prevent/control diabetes are cost saving or very cost-effective and supported by strong evidence. Policy makers should consider giving these interventions a higher priority.

A cost effectiveness study of integrated care in health services delivery: a diabetes program in Australia

BACKGROUND

Type 2 diabetes is rapidly growing as a proportion of the disease burden in Australia as elsewhere. This study addresses the cost effectiveness of an integrated approach to assisting general practitioners (GPs) with diabetes management. This approach uses a centralized database of clinical data of an Australian Division of General Practice (a network of GPs) to co-ordinate care according to national guidelines.

METHODS

Long term outcomes for patients in the program were derived using clinical parameters after 5 years of program participation, and the United Kingdom Prospective Diabetes Study (UKPDS) Outcomes Model, to project outcomes for 40 years from the time of diagnosis and from 5 years post-diagnosis. Cost information was obtained from a range of sources. While program costs are directly available, and costs of complications can be estimated from the UKPDS model, other costs are estimated by comparing costs in the Division with average costs across the state or the nation. The outcome and cost measures are used derive incremental cost-effectiveness ratios.

RESULTS

The clinical data show that the program is effective in the short term, with improvement or no statistical difference in most clinical measures over 5 years. Average HbA1c levels increased by less than expected over the 5 year period. While the program is estimated to generate treatment cost savings, overall net costs are positive. However, the program led to projected improvements in expected life years and Quality Adjusted Life Expectancy (QALE), with incremental cost effectiveness ratios of $A8,106 per life-year saved and $A9,730 per year of QALE gained.

CONCLUSIONS

The combination of an established model of diabetes progression and generally available data has provided an opportunity to establish robust methods of testing the cost effectiveness of a program for which a formal control group was not available. Based on this methodology, integrated health care delivery provided by a network of GPs improved health outcomes of type 2 diabetics with acceptable cost effectiveness, which suggests that similar outcomes may be obtained elsewhere.

A work force model to support the adoption of best practice care in chronic diseases - a missing piece in clinical guideline implementation

The development and implementation of an evidence-based approach to health workforce planning is a necessary step to achieve access to best practice chronic disease management. In its absence, the widely reported failure in implementation of clinical best practice guidelines is almost certain to continue. This paper describes a demand model to estimate the community-based primary care health workforce consistent with the delivery of best practice chronic disease management and prevention. The model takes a geographic region as the planning frame and combines data about the health status of the regional population by disease category and stage, with best practice guidelines to estimate the clinical skill requirement or competencies for the region. The translation of the skill requirement into a service requirement can then be modelled, incorporating various assumptions about the occupation group to deliver nominated competencies. The service requirement, when compared with current service delivery, defines the gap or surplus in services. The results of the model could be used to inform service delivery as well as a workforce supply strategy.

Raising diabetes awareness in the public domain

Type 2 diabetes mellitus (T2DM) is a chronic, debilitating and costly disease associated with severe complications, and has been recognised as such by the United Nations (UN). But despite being a leading cause of death and serious disability worldwide, the public often perceive T2DM as a relatively mild condition. Furthermore, many people do not know that T2DM is preventable and that steps can be taken to minimise the risk of developing the disease. Improved public awareness of T2DM and its link with obesity and physical inactivity is critical, not only to prevention but also management of diabetes. Recognising this need, the UN has issued a resolution calling on member states to observe World Diabetes Day and implement education and mass media initiatives to raise public awareness of diabetes and its complications. This article reviews selected local, national and international public awareness campaigns to illustrate the range of initiatives that together can work towards the goals of the UN Resolution. By building understanding of diabetes, changing beliefs and attitudes and promoting positive behaviours, such initiatives can help combat the global diabetes epidemic and improve the health and wellbeing of people.

A review of the cost-effectiveness of face-to-face behavioural interventions for smoking, physical activity, diet and alcohol

OBJECTIVE

To assess the evidence for the cost-effectiveness of health behaviour interventions that address the major behavioural risk factors for chronic disease, including smoking, physical inactivity, poor diet, and alcohol misuse.

METHODS

Medical and economic databases were searched for relevant economic evaluations. Studies were critically appraised using a published 35-point checklist, and the results are described using a narrative approach, noting methodological limitations. The review included 64 studies from 1995-2005, including 17 reports on multiple behaviour interventions.

RESULTS

There was considerable variation among the studies by target populations, intervention components, primary outcomes, and economic methods, but the reported incremental cost-effectiveness ratios were consistently low (e.g. <14,000 Euros per quality-adjusted life-year gained for smoking-cessation programmes in 2006 Euros) as compared to certain preventive pharmaceutical and invasive interventions. Interventions targeting high-risk-population subgroups were relatively better value for money as compared to those targeting general populations.

DISCUSSION

In general, the results of this review demonstrate favourable cost-effectiveness for smoking interventions, physical activity interventions and multiple behaviour interventions in high-risk groups. Although alcohol and dietary interventions appeared to be economically favourable, it is difficult to draw conclusions because of the variety in study outcomes. However, methodological limitations weaken the generalizability of findings, and suggest that the results of any given study should be considered carefully when being used to inform resource allocation.

Lifestyle interventions are cost-effective in people with different levels of diabetes risk: results from a modeling study

OBJECTIVE

In the current study we explore the long-term health benefits and cost-effectiveness of both a community-based lifestyle program for the general population (community intervention) and an intensive lifestyle intervention for obese adults, implemented in a health care setting (health care intervention).

RESEARCH DESIGN AND METHODS

Short-term intervention effects on BMI and physical activity were estimated from the international literature. The National Institute for Public Health and the Environment Chronic Diseases Model was used to project lifetime health effects and effects on health care costs for minimum and maximum estimates of short-term intervention effects. Cost-effectiveness was evaluated from a health care perspective and included intervention costs and related and unrelated medical costs. Effects and costs were discounted at 1.5 and 4.0% annually.

RESULTS

One new case of diabetes per 20 years was prevented for every 7-30 participants in the health care intervention and for every 300-1,500 adults in the community intervention. Intervention costs needed to prevent one new case of diabetes (per 20 years) were lower for the community intervention (2,000-9,000 euros) than for the health care intervention (5,000-21,000 euros). The cost-effectiveness ratios were 3,100-3,900 euros per quality-adjusted life-year (QALY) for the community intervention and 3,900-5,500 euros per QALY for the health care intervention.

CONCLUSIONS

Health care interventions for high-risk groups and community-based lifestyle interventions targeted to the general population (low risk) are both cost-effective ways of curbing the growing burden of diabetes.

The answer to diabetes prevention: science, surgery, service delivery, or social policy?

The diabetes and obesity epidemics are closely intertwined. International randomized controlled trials demonstrate that, in high-risk individuals, type 2 diabetes can be prevented or at least delayed through lifestyle modification and, to a lesser degree, medication. We explored the relative roles of science, surgery, service delivery, and social policy in preventing diabetes. Although it is clear that there is a role for all, diabetes is a complex problem that demands commitment across a range of government and nongovernment agencies to be effectively controlled. Accordingly, we argue that social policy is the key to achieving and sustaining social and physical environments required to achieve widespread reductions in both the incidence and prevalence of diabetes.

Routinely collected general practice data aids identification of people with hyperglycaemia and metabolic syndrome

AIMS

To assess the performance of a risk score comprising data routinely available in general practice records (age, gender, body mass index, family history of diabetes, smoking habits and prescribed anti-hypertensive drugs or steroids) in detecting diabetes, impaired glucose tolerance and metabolic syndrome.

METHODS

In a population-based, cross-sectional study in a semi-rural general practice in Jutland, Denmark, Cambridge Risk Scores were calculated for 1355 patients without known diabetes (69% response rate) who completed questionnaires and underwent anthropometric measurement and an oral glucose tolerance test.

RESULTS

Prevalences of diabetes, impaired glucose tolerance and metabolic syndrome were 2.29% (95% CI: 1.56-3.23), 6.64% (95% CI: 5.38-8.10) and 13.4% (95% CI: 11.5-15.2), respectively. Area under the ROC curve for the risk score and diabetes was 83.8% (75.9-91.7) and for metabolic syndrome [European Group for the Study of Insulin Resistance (EGIR)] was 78.1% (74.6-81.6). Twenty per cent of the population had a risk score above 0.246; at this threshold the sensitivity to detect diabetes was 71.0% (53.4-83.9), the specificity 81.2% (79.0-83.2), positive predictive value 8.1% (6.6-10.0) and likelihood ratio 3.77 (2.94-4.85). For metabolic syndrome (EGIR) corresponding values for sensitivity were 50.3% (43.1-57.5), specificity 84.7% (82.5-85.6), positive predictive value 33.6% (28.2-39.4), and likelihood ratio 3.28 (2.69-4.00).

CONCLUSIONS

Undiagnosed hyperglycaemia and metabolic syndrome are common. The Cambridge Risk Score is a practical first step in a screening procedure to identify individuals with these disorders who might benefit from diagnostic testing or to direct preventive interventions.

Cost-effectiveness analyses and modelling the lifetime costs and benefits of health-behaviour interventions

BACKGROUND

We describe an approach to estimating the cost-effectiveness of an intervention that changes health behaviour. The method captures the lifetime costs and benefits incurred by participants in an ongoing cluster-randomized controlled trial of an intervention that aims to change health behaviour. The existing literature only captures short-term economic and health outcomes.

METHODS

We develop a state-transition Markov model of how individuals move between different health behaviour states over time. We simulate hypothetical data to describe the costs and health benefits of the intervention, illustrate how the data collected in the ongoing randomized controlled trial can be used and demonstrate how incremental cost-effectiveness ratios are estimated.

RESULTS

On the basis of the simulated (i.e. hypothetical) data, we estimate the cost per quality-adjusted life year. The estimate reflects the lifetime health and economic consequences of the intervention.

DISCUSSION

The method used for the cost-effectiveness analysis described in this paper is appropriate for investigating whether interventions that change health behaviour in relation to chronic diseases represent good value for money as compared to alternative uses of scarce healthcare resources.

Population impact of strategies for identifying groups at high risk of type 2 diabetes

BACKGROUND

To assess the incidence of diabetes among sub-groups of the population defined by the presence of one or more simple risk factors, and to investigate population stratification as a means of identifying groups at high risk of diabetes.

METHODS

Data from EPIC-Norfolk (1993-1998), a population-based cohort study of 24,714 men and women aged 40-78 years without self-reported diabetes at baseline, were analyzed. During 12 years of follow-up, 608 new cases of diabetes were recorded.

RESULTS

Age (RR 1.03; 95% CI 1.02, 1.04), parental history of diabetes (RR 2.15; 95% CI 1.80, 2.57), BMI (RR 1.76; 95% CI 1.53, 2.02) and physical activity (RR 0.72-0.77 (reference sedentary)) were independently related to risk of diabetes. Sedentary, obese individuals aged over 55 years, with a parental history of diabetes were 18 times more likely to develop diabetes than those in the lowest risk group.

CONCLUSION

Sedentary, obese men and women over 55 years with a parental history of diabetes form a readily identifiable group, which could be targeted for screening and primary prevention. Groups such as that defined by physical inactivity alone would be more suitable for population level approaches.

A population-based model for priority setting across the care continuum and across modalities

BACKGROUND

The Health-sector Wide (HsW) priority setting model is designed to shift the focus of priority setting away from 'program budgets'--that are typically defined by modality or disease-stage--and towards well-defined target populations with a particular disease/health problem.

METHODS

The key features of the HsW model are i) a disease/health problem framework, ii) a sequential approach to covering the entire health sector, iii) comprehensiveness of scope in identifying intervention options and iv) the use of objective evidence. The HsW model redefines the unit of analysis over which priorities are set to include all mutually exclusive and complementary interventions for the prevention and treatment of each disease/health problem under consideration. The HsW model is therefore incompatible with the fragmented approach to priority setting across multiple program budgets that currently characterises allocation in many health systems. The HsW model employs standard cost-utility analyses and decision-rules with the aim of maximising QALYs contingent upon the global budget constraint for the set of diseases/health problems under consideration. It is recognised that the objective function may include non-health arguments that would imply a departure from simple QALY maximisation and that political constraints frequently limit degrees of freedom. In addressing these broader considerations, the HsW model can be modified to maximise value-weighted QALYs contingent upon the global budget constraint and any political constraints bearing upon allocation decisions.

RESULTS

The HsW model has been applied in several contexts, recently to osteoarthritis, that has demonstrated both its practical application and its capacity to derive clear evidenced-based policy recommendations.

CONCLUSION

Comparisons with other approaches to priority setting, such as Programme Budgeting and Marginal Analysis (PBMA) and modality-based cost-effectiveness comparisons, as typified by Australia's Pharmaceutical Benefits Advisory Committee process for the listing of pharmaceuticals for government funding, demonstrate the value added by the HsW model notably in its greater likelihood of contributing to allocative efficiency.

The cost-effectiveness of health communication programs: what do we know?

While a considerable body of evidence has emerged supporting the effectiveness of communication programs in augmenting health, only a very small subset of studies has examined also whether these programs are cost-effective, that is, whether they achieve greater health gains for available financial resources than alternative interventions. In this article, we examine the available literature on the cost-effectiveness of health behavior change communication programs, focusing on communication interventions involving mass media, and, to a lesser extent, community mobilization and interpersonal communication or counseling. Our objective is to identify the state of past and current research efforts of the cost-effectiveness of behavior change communication programs. This review makes three principal conclusions. First, the analysis of the cost-effectiveness of health communication programs commonly has not been performed. Second, the studies reviewed here have utilized a considerable diversity of methods and have reflected varying levels of quality and adherence to standard cost-effectiveness methodologies. This leads to problems of transparency, comparability, and generalizability. Third, while the available studies generally are indicative of the cost-effectiveness of communication interventions relative to alternatives, the evidence base clearly needs to be expanded by additional rigorous cost-effectiveness analyses.

Cost effectiveness of preventive interventions in type 2 diabetes mellitus: a systematic literature review

A systematic review of the literature was conducted to give an overview of economic evaluations of preventive interventions in type 2 diabetes mellitus. The interventions were sorted by type of preventive intervention (primary, secondary or tertiary) and by category (e.g. education, medication for hypertension). Several databases were searched for studies published between January 1990 and May 2004 on the three types of preventive intervention. For each study selected, inclusion of specific components from a standardised list of items, including quality, was recorded in a database. Summary tables were generated based on the database.A number of conclusions were drawn from this review. The most important was that strict blood pressure control was a more cost-effective intervention than less strict control, as shown by six studies reporting cost savings to very low costs per life-year gained. Primary and secondary prevention of type 2 diabetes were also highly cost effective, but these results were based on very few studies. Medications to reduce weight and hyperglycaemia together were cost effective compared with conventional interventions. Finally, the separate results regarding medications to reduce weight, hyperglycaemia and hypercholesterolaemia varied enormously, thus no conclusion could be drawn and further economic analysis is required.

The ProActive trial protocol - a randomised controlled trial of the efficacy of a family-based, domiciliary intervention programme to increase physical activity among individuals at high risk of diabetes [ISRCTN61323766]

BACKGROUND

Increasing prevalence of obesity and disorders associated with sedentary living constitute a major global public health problem. While previous evaluations of interventions to increase physical activity have involved communities or individuals with established disease, less attention has been given to interventions for individuals at risk of disease.

METHODS/DESIGN

ProActive aims to evaluate the efficacy of a theoretical, evidence- and family-based intervention programme to increase physical activity in a sedentary population, defined as being at-risk through having a parental family history of diabetes. Primary care diabetes or family history registers were used to recruit 365 individuals aged 30-50 years, screened for activity level. Participants were assigned by central randomisation to three intervention programmes: brief written advice (comparison group), or a psychologically based behavioural change programme, delivered either by telephone (distance group) or face-to-face in the family home over one year. The protocol-driven intervention programme is delivered by trained facilitators, and aims to support increases in physical activity through the introduction and facilitation of a range of self-regulatory skills (e.g. goal setting). The primary outcome is daytime energy expenditure and its ratio to resting energy expenditure, measured at baseline and one year using individually calibrated heart rate monitoring. Secondary measures include self-report of individual and family activity, psychological mediators of behaviour change, physiological and biochemical correlates, acceptability, and costs, measured at baseline, six months and one year. The primary intention to treat analysis will compare groups at one-year post randomisation. Estimation of the impact on diabetes incidence will be modelled using data from a parallel ten-year cohort study using similar measures.

DISCUSSION

ProActive is the first efficacy trial of an intervention programme to promote physical activity in a defined high-risk group accessible through primary care. The intervention programme is based on psychological theory and evidence; it introduces and facilitates the use of self-regulatory skills to support behaviour change and maintenance. The trial addresses a range of methodological weaknesses in the field by careful specification and quality assurance of the intervention programme, precise characterisation of participants, year-long follow-up and objective measurement of physical activity. Due to report in 2005, ProActive will provide estimates of the extent to which this approach could assist at-risk groups who could benefit from changes in behaviours affecting health, and inform future pragmatic trials.

The economics of screening and treatment in type 2 diabetes mellitus

A systematic review of the literature was conducted to identify articles on the economics of type 2 diabetes mellitus. Articles were classified into two main categories: cost/burden-of-illness studies of type 2 diabetes and economic evaluations of type 2 diabetes interventions. This systematic review was supplemented by an overview of the findings relating to economic evaluations of associated diabetic complications. A number of conclusions emerge from this review, the most important of which is that intensive treatment of patients with type 2 diabetes appears to be relatively cost effective compared with more conservative strategies. This finding reflects the cost offsets that arise from the range and degree of complications attributable to diabetes. Primary prevention of type 2 diabetes also appears to be cost effective, particularly in high-risk groups. The evidence on screening for type 2 diabetes is less conclusive and further economic analysis is required.

Diabetes risk score: towards earlier detection of type 2 diabetes in general practice

BACKGROUND

Type 2 diabetes is common, costly and often goes unrecognised for many years. When patients are diagnosed, the majority exhibit associated tissue damage or established cardiovascular risk. Evidence is accumulating that earlier detection and management of diabetes and related metabolic abnormalities may be beneficial. We aimed to develop and evaluate a score based on routinely collected information to identify people at risk of having undetected diabetes.

METHODS

A population-based sample of 1077 people, aged 40 to 64 years, without known diabetes, from a single Cambridgeshire general practice, underwent clinical assessment including an oral glucose tolerance test. In a separate 12-month study, 41 practices in southern England reported clinical details of patients aged 40 to 64 years with newly diagnosed Type 2 diabetes. A notional population was created by random selection and pooling of half of each dataset. Data were entered into a regression model to produce a formula predicting the risk of diabetes. The performance of this risk score in detecting diabetes was tested in an independent, randomly selected, population-based sample.

RESULTS

Age, gender, body mass index, steroid and antihypertensive medication, family and smoking history contributed to the score. In the test population at 72% specificity, the sensitivity of the score was 77% and likelihood ratio 2.76. The area under the receiver-operating characteristic curve was 80%.

CONCLUSIONS

A simple score, using only data that are routinely collected in general practice, can help identify those at risk of diabetes. This score could contribute to efficient earlier detection through case-finding or targeted screening.