Alastair Gray

The economic burden of back pain in the UK

Abstract This paper reports the results of a ‘cost‐of‐illness’ study of the socio‐economic costs of back pain in the UK. It estimates the direct health care cost of back pain in 1998 to be £1632 million. Approximately 35% of this cost relates to services provided in the private sector and thus is most likely paid for directly by patients and their families. With respect to the distribution of cost across different providers, 37% relates to care provided by physiotherapists and allied specialists, 31% is incurred in the hospital sector, 14% relates to primary care, 7% to medication, 6% to community care and 5% to radiology and imaging used for investigation purposes. However, the direct cost of back pain is insignificant compared to the cost of informal care and the production losses related to it, which total £10668 million. Overall, back pain is one of the most costly conditions for which an economic analysis has been carried out in the UK and this is in line with findings in other countries. Further research is needed to establish the cost‐effectiveness of alternative back pain treatments, so as to minimise cost and maximise the health benefit from the resources used in this area.

A model to estimate the lifetime health outcomes of patients with type 2 diabetes: the United Kingdom Prospective Diabetes Study (UKPDS) Outcomes Model (UKPDS no. 68).

Aims/hypothesisThe aim of this study was to develop a simulation model for Type 2 diabetes that can be used to estimate the likely occurrence of major diabetes-related complications over a lifetime, in order to calculate health economic outcomes such as quality-adjusted life expectancy.MethodsEquations for forecasting the occurrence of seven diabetes-related complications and death were estimated using data on 3642 patients from the United Kingdom Prospective Diabetes Study (UKPDS). After examining the internal validity, the UKPDS Outcomes Model was used to simulate the mean difference in expected quality-adjusted life years between the UKPDS regimens of intensive and conventional blood glucose control.ResultsThe model’s forecasts fell within the 95% confidence interval for the occurrence of observed events during the UKPDS follow-up period. When the model was used to simulate event history over patients’ lifetimes, those treated with a regimen of conventional glucose control could expect 16.35 undiscounted quality-adjusted life years, and those receiving treatment with intensive glucose control could expect 16.62 quality-adjusted life years, a difference of 0.27 (95% CI: −0.48 to 1.03).Conclusions/interpretationsThe UKPDS Outcomes Model is able to simulate event histories that closely match observed outcomes in the UKPDS and that can be extrapolated over patients’ lifetimes. Its validity in estimating outcomes in other groups of patients, however, remains to be evaluated. The model allows simulation of a range of long-term outcomes, which should assist in informing future economic evaluations of interventions in Type 2 diabetes.

Estimating utility values for health states of type 2 diabetic patients using the EQ-5D (UKPDS 62).

Purpose . The aim of this study was to analyze quality-of-life data from the United Kingdom Prospective Diabetes Study (UKPDS) to estimate the impact of diabetes-related complications on utility-based measures of quality of life. Methods . The EuroQol EQ-5D instrument was administered in 1996 to 3667 UKPDS patients with type 2 diabetes. Tobit and censored least absolute deviations (CLAD) regression analysis based on data from the 3192 respondents was used to estimate the impact of major complications on (1) the visual analog scale (VAS) and (2) the EQ-5D utilities derived from population-based time trade-off values. Results . Using the tobit model, the effect on tariff values was as follows: myocardial infarction = -0.055 (95% confidence interval [CI] = -0.067, -0.042), blindness in 1 eye = -0.074 (95% CI = -0.124, -0.052), ischemic heart disease = -0.090 (95% CI = -0.126, -0.054), heart failure = -0.108 (95% CI = -0.169, -0.048), stroke = -0.164 (95% CI = -0.222, -0.105), and amputation = -0.280 (95% CI = -0.389, -0.170). The impact on the VAS scores was smaller, but the ranking was identical. Estimates of these effects, based on the nonparametric CLAD estimator, are also reported and compared. Conclusion . These results demonstrate the magnitude of the impact of 6 complications on utility-based measures of quality of life, which can be used to estimate the outcome of interventions that reduce these diabetes-related complications.

Cost effectiveness of an intensive blood glucose control policy in patients with type 2 diabetes: economic analysis alongside randomised controlled trial (UKPDS 41)

Abstract Objective: To estimate the cost effectiveness of conventional versus intensive blood glucose control in patients with type 2 diabetes. Design: Incremental cost effectiveness analysis alongside randomised controlled trial. Setting: 23 UK hospital clinic based study centres. Participants: 3867 patients with newly diagnosed type 2 diabetes (mean age 53 years). Interventions: Conventional (primarily diet) glucose control policy versus intensive control policy with a sulphonylurea or insulin. Main outcome measures: Incremental cost per event-free year gained within the trial period. Results: Intensive glucose control increased trial treatment costs by £695 (95% confidence interval £555 to £836) per patient but reduced the cost of complications by £957 (£233 to £1681) compared with conventional management. If standard practice visit patterns were assumed rather than trial conditions, the incremental cost of intensive management was £478 (-£275 to £1232) per patient. The within trial event-free time gained in the intensive group was 0.60 (0.12 to 1.10) years and the lifetime gain 1.14 (0.69 to 1.61) years. The incremental cost per event-free year gained was £1166 (costs and effects discounted at 6% a year) and £563 (costs discounted at 6% a year and effects not discounted). Conclusions: Intensive blood glucose control in patients with type 2 diabetes significantly increased treatment costs but substantially reduced the cost of complications and increased the time free of complications.

Measuring the impact of menopausal symptoms on quality of life.

OBJECTIVE--To examine the impact of menopausal symptoms on the overall quality of life of women. DESIGN--Data collection with a questionnaire administered by an interviewer, incorporating two different quality of life measurement techniques (time trade off and rating scale). SETTING--Specialist menopause clinic and two general practices in Oxford. SUBJECTS--63 women aged 45-60 years recruited opportunistically during a clinic or appointment with a general practitioner; no exclusion criteria. RESULTS--Subjects gave very low quality of life ratings for health states with menopausal symptoms. The time trade off method of measuring preferences for these health states (on a scale from 0 to 1, where preference for full health is given as 1) yielded utility values of 0.64 for severe menopausal symptoms and 0.85 for mild symptoms. The rating scale measurement technique yielded even lower values: utilities of 0.30 and 0.65 were obtained for severe and mild symptoms respectively. Kappa scores indicated that the two methods produced results that were poorly related but not contradictory. Comparison of quality of life ratings before and after treatment with hormone replacement therapy showed significant improvements: with the rating scale measurement technique mean increases in utility values after the relief of severe and mild menopausal symptoms were 0.56 and 0.18 respectively. CONCLUSIONS--Quality of life may be severely compromised in women with menopausal symptoms, and perceived improvements in quality of life in users of hormone replacement therapy seem to be substantial. This emphasises the need to include quality of life measurements when assessing outcomes of hormone replacement therapy. Several limitations may exist with widely applied measurement techniques, calling for the development of appropriate and well validated instruments for measuring quality of life associated with reduced health states.

Randomized trial to compare bilateral vs. single internal mammary coronary artery bypass grafting: 1-year results of the Arterial Revascularisation Trial (ART)

AIMS Observational data suggest that the use of bilateral internal mammary arteries (BIMA) during coronary artery bypass graft surgery provides superior revascularization to a single internal mammary artery (SIMA), but concerns about safety have prevented the widespread use of BIMA. The Arterial Revascularisation Trial (ART) is a randomized trial of BIMA vs. SIMA, with a primary outcome of survival at 10 years. This paper reports mortality, morbidity, and resource use data at 1 year. METHODS AND RESULTS Coronary artery bypass graft patients were enrolled in 28 hospitals in seven countries. Three thousand one hundred and two patients were randomly assigned to SIMA (n = 1554) or BIMA (n = 1548). The mean number of grafts was 3 for both groups. Forty per cent of the SIMA procedures and 42% of the BIMA were performed off-pump. Mortality at 30 days was 18 of 1548 (1.2%) for SIMA and 19 of 1537 (1.2%) for BIMA, and at 1 year was 36 of 1540 (2.3%) and 38 of 1529 (2.5%), respectively. The rates of stroke, myocardial infarction, and repeat revascularization were all ≤2% at 1 year and similar between the two groups. Sternal wound reconstruction was required in 0.6 and 1.9% of the SIMA and BIMA groups, respectively. CONCLUSION Data from ART demonstrate similar clinical outcomes for SIMA and BIMA at 1 year but BIMA grafts are associated with a small absolute increase (1.3%) in the need for sternal wound reconstruction. The results suggest that the use of BIMA grafts is feasible on a routine basis. The 10-year results of the ART will confirm whether BIMA grafting results in lower mortality and the need for repeat intervention. TRIAL REGISTRATION Controlled-trials.com (ISRCTN46552265).

The Distribution of Health Care Costs and Their Statistical Analysis for Economic Evaluation

Objective: Where patient level data are available on health care costs, it is natural to use statistical analysis to describe the differences in cost between alternative treatments. Health care costs are, however, commonly considered to be skewed, which could present problems for standard statistical tests. This review examines how authors report the distributional form of health care cost data and how they have analysed their results. Method: A review of cost-effectiveness studies that collected patient-level data on health care costs. To supplement the review, five datasets on health care costs are examined. Consideration is given to the use of parametric methods on the transformed scale and to non-parametric methods of analysing skewed cost data. Results: Since economic analysis requires estimation in monetary units, the usefulness of transformation-based methods is limited by the inability to retransform cost differences to the original scale. Non-parametric rank sum methods were also found to be of limited use for economic analysis, partly due to the focus on hypothesis testing rather than estimation. Overall, the non-parametric approach of bootstrapping was found to offer a useful test of the appropriateness of parametric assumptions and an alternative method of estimation where those assumptions were found not to hold. Conclusions: Guidelines for the analysis of skewed health care cost data are offered.

The impact of diabetes-related complications on healthcare costs: results from the United Kingdom Prospective Diabetes Study (UKPDS Study No. 65)

Aims To develop a model for estimating the immediate and long‐term healthcare costs associated with seven diabetes‐related complications in patients with Type 2 diabetes participating in the UK Prospective Diabetes Study (UKPDS).

Could targeted food taxes improve health

Objective: To examine the effects on nutrition, health and expenditure of extending value added tax (VAT) to a wider range of foods in the UK. Method: A model based on consumption data and elasticity values was constructed to predict the effects of extending VAT to certain categories of food. The resulting changes in demand, expenditure, nutrition and health were estimated. Three different tax regimens were examined: (1) taxing the principal sources of dietary saturated fat; (2) taxing foods defined as unhealthy by the SSCg3d nutrient scoring system; and (3) taxing foods in order to obtain the best health outcome. Data: Consumption patterns and elasticity data were taken from the National Food Survey of Great Britain. The health effects of changing salt and fat intake were from previous meta-analyses. Results: (1) Taxing only the principal sources of dietary saturated fat is unlikely to reduce the incidence of cardiovascular disease because the reduction in saturated fat is offset by a rise in salt consumption. (2) Taxing unhealthy foods, defined by SSCg3d score, might avert around 2300 deaths per annum, primarily by reducing salt intake. (3) Taxing a wider range of foods could avert up to 3200 cardiovascular deaths in the UK per annum (a 1.7% reduction). Conclusions: Taxing foodstuffs can have unpredictable health effects if cross-elasticities of demand are ignored. A carefully targeted fat tax could produce modest but meaningful changes in food consumption and a reduction in cardiovascular disease.

Effect of 3 to 5 Years of Scheduled CEA and CT Follow-up to Detect Recurrence of Colorectal Cancer: The FACS Randomized Clinical Trial

IMPORTANCE Intensive follow-up after surgery for colorectal cancer is common practice but is based on limited evidence. OBJECTIVE To assess the effect of scheduled blood measurement of carcinoembryonic antigen (CEA) and computed tomography (CT) as follow-up to detect recurrent colorectal cancer treatable with curative intent. DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial in 39 National Health Service hospitals in the United Kingdom; 1202 eligible participants were recruited between January 2003 and August 2009 who had undergone curative surgery for primary colorectal cancer, including adjuvant treatment if indicated, with no evidence of residual disease on investigation. INTERVENTIONS Participants were randomly assigned to 1 of 4 groups: CEA only (n = 300), CT only (n = 299), CEA+CT (n = 302), or minimum follow-up (n = 301). Blood CEA was measured every 3 months for 2 years, then every 6 months for 3 years; CT scans of the chest, abdomen, and pelvis were performed every 6 months for 2 years, then annually for 3 years; and the minimum follow-up group received follow-up if symptoms occurred. MAIN OUTCOMES AND MEASURES The primary outcome was surgical treatment of recurrence with curative intent; secondary outcomes were mortality (total and colorectal cancer), time to detection of recurrence, and survival after treatment of recurrence with curative intent. RESULTS After a mean 4.4 (SD, 0.8) years of observation, cancer recurrence was detected in 199 participants (16.6%; 95% CI, 14.5%-18.7%) overall; 71 of 1202 participants (5.9%; 95% CI, 4.6%-7.2%) were treated for recurrence with curative intent, with little difference according to Dukes staging (stage A, 5.1% [13/254]; stage B, 6.1% [34/553]; stage C, 6.2% [22/354]). Surgical treatment of recurrence with curative intent was 2.3% (7/301) in the minimum follow-up group, 6.7% (20/300) in the CEA group, 8% (24/299) in the CT group, and 6.6% (20/302) in the CEA+CT group. Compared with minimum follow-up, the absolute difference in the percentage of patients treated with curative intent in the CEA group was 4.4% (95% CI, 1.0%-7.9%; adjusted odds ratio [OR], 3.00; 95% CI, 1.23-7.33), in the CT group was 5.7% (95% CI, 2.2%-9.5%; adjusted OR, 3.63; 95% CI, 1.51-8.69), and in the CEA+CT group was 4.3% (95% CI, 1.0%-7.9%; adjusted OR, 3.10; 95% CI, 1.10-8.71). The number of deaths was not significantly different in the combined intensive monitoring groups (CEA, CT, and CEA+CT; 18.2% [164/901]) vs the minimum follow-up group (15.9% [48/301]; difference, 2.3%; 95% CI, -2.6% to 7.1%). CONCLUSIONS AND RELEVANCE Among patients who had undergone curative surgery for primary colorectal cancer, intensive imaging or CEA screening each provided an increased rate of surgical treatment of recurrence with curative intent compared with minimal follow-up; there was no advantage in combining CEA and CT. If there is a survival advantage to any strategy, it is likely to be small. TRIAL REGISTRATION isrctn.org Identifier: 41458548.