Tracey Sach

The relationship between body mass index and health-related quality of life: comparing the EQ-5D, EuroQol VAS and SF-6D

Background:No other studies have compared the relationship between body mass index (BMI) and health-related quality of life (HRQL) on more than one utility measure. Estimating the HRQL effects of obesity on a (common) utility scale enables the relative cost-effectiveness of interventions designed to alleviate obesity to be estimated.Objective:To examine the relationship between BMI and HRQL according to the EQ-5D, EuroQol visual analogue scale (EQ-VAS) and SF-6D.Methods:Patients aged ⩾45 years at one UK general practice were asked to complete the EQ-5D, EQ-VAS, SF-36 questionnaire (used to derive the SF-6D), and information on their characteristics and co-morbidity. Body mass index was categorized according to the World Health Organization (WHO) recommendations. Regression analysis was used to compare the HRQL of normal BMI patients to the HRQL of patients in other BMI categories, while controlling for patient characteristics and co-morbidity.Results:A total of 1865 patients responded (67%), mean BMI 26.0 kg/m2, 16% obese (BMI⩾30). Patients with back pain, hip pain, knee pain, asthma, diabetes or osteoarthritis were also significantly more likely to be obese. After controlling for other factors, compared to normal BMI patients, obese patients had a lower HRQL according to the EQ-5D (P<0.01), EQ-VAS (P<0.001) and SF-6D (P<0.001). Pre-obese patients were not estimated to have a significantly lower HRQL, and underweight patients were only estimated to have a significantly lower HRQL according to the SF-6D. These results arose because, on the EQ-5D, obese patients were found to have significantly more problems with mobility and pain, compared to physical functioning, social functioning and role limitations on the SF-6D. Whereas, according to the SF-6D, underweight patients had significantly more problems on the dimension of role limitation.Conclusion:The EQ-5D, EQ-VAS and SF-6D were in agreement that, relative to a normal BMI, obesity is associated with a lower HRQL, even after controlling for patient characteristics and co-morbidity. These three measures are thereby sensitive to the HRQL effects of obesity and can be used to estimate the cost-effectiveness of interventions designed to alleviate obesity.

Effects of dietary intervention and quadriceps strengthening exercises on pain and function in overweight people with knee pain: randomised controlled trial

Objective To determine whether dietary intervention or knee strengthening exercise, or both, can reduce knee pain and improve knee function in overweight and obese adults in the community. Design Pragmatic factorial randomised controlled trial. Setting Five general practices in Nottingham. Participants 389 men and women aged 45 and over with a body mass index (BMI) of ≥28.0 and self reported knee pain. Interventions Participants were randomised to dietary intervention plus quadriceps strengthening exercises; dietary intervention alone; quadriceps strengthening exercises alone; advice leaflet only (control group). Dietary intervention consisted of individualised healthy eating advice that would reduce normal intake by 2.5 MJ (600 kcal) a day. Interventions were delivered at home visits over a two year period. Main outcome measures The primary outcome was severity of knee pain scored with the Western Ontario McMaster (WOMAC) osteoarthritis index at 6, 12, and 24 months. Secondary outcomes (all at 24 months) included WOMAC knee physical function and stiffness scores and selected domains on the SF-36 and the hospital anxiety and depression index. Results 289 (74%) participants completed the trial. There was a significant reduction in knee pain in the knee exercise groups compared with those in the non-exercise groups at 24 months (percentage risk difference 11.61, 95% confidence interval 1.81% to 21.41%). The absolute effect size (0.25) was moderate. The number needed to treat to benefit from a ≥30% improvement in knee pain at 24 months was 9 (5 to 55). In those randomised to knee exercise improvement in function was evident at 24 months (mean difference −3.64, −6.01 to −1.27). The mean difference in weight loss at 24 months in the dietary intervention group compared with no dietary intervention was 2.95 kg (1.44 to 4.46); for exercise versus no exercise the difference was 0.43 kg (−0.82 to 1.68). This difference in weight loss was not associated with improvement in knee pain or function but was associated with a reduction in depression (absolute effect size 0.19). Conclusions A home based, self managed programme of simple knee strengthening exercises over a two year period can significantly reduce knee pain and improve knee function in overweight and obese people with knee pain. A moderate sustained weight loss is achievable with dietary intervention and is associated with reduced depression but is without apparent influence on pain or function. Trial registration Current Controlled Trials ISRCTN 93206785.

Community falls prevention for people who call an emergency ambulance after a fall: randomised controlled trial

Objective To evaluate whether a service to prevent falls in the community would help reduce the rate of falls in older people who call an emergency ambulance when they fall but are not taken to hospital. Design Randomised controlled trial. Setting Community covered by four primary care trusts, England. Participants 204 adults aged more than 60 living at home or in residential care who had fallen and called an emergency ambulance but were not taken to hospital. Interventions Referral to community fall prevention services or standard medical and social care. Main outcome measures The primary outcome was the rate of falls over 12 months, ascertained from monthly diaries. Secondary outcomes were scores on the Barthel index, Nottingham extended activities of daily living scale, and falls efficacy scale at baseline and by postal questionnaire at 12 months. Analysis was by intention to treat. Results 102 people were allocated to each group. 99 (97%) participants in the intervention group received the intervention. Falls diaries were analysed for 88.6 person years in the intervention group and 84.5 person years in the control group. The incidence rates of falls per year were 3.46 in the intervention group and 7.68 in the control group (incidence rate ratio 0.45, 95% confidence interval 0.35 to 0.58, P<0.001). The intervention group achieved higher scores on the Barthel index and Nottingham extended activities of daily living and lower scores on the falls efficacy scale (all P<0.05) at the 12 month follow-up. The number of times an emergency ambulance was called because of a fall was significantly different during follow-up (incidence rate ratio 0.60, 95% confidence interval 0.40 to 0.92, P=0.018). Conclusion A service to prevent falls in the community reduced the fall rate and improved clinical outcome in the high risk group of older people who call an emergency ambulance after a fall but are not taken to hospital. Trial registration Current Controlled Trials ISRCTN67535605.

Paediatric cochlear implantation: the views of parents

The purpose of this study was to understand the parental perspective on paediatric cochlear implantation over time. Face-to-face semi-structured interviews were conducted with 216 families of children who were implanted at the Nottingham Paediatric Cochlear Implant Programme between 1989 and 2002, and who were attending an appointment during the study period (July 2001–August 2002). The qualitative data revealed that time played an important role in family experiences of paediatric cochlear implantation. Expectations were continually revised throughout the process, as a result of new knowledge and new technological developments. The results show that outcomes are highly individualistic although parents had a shared hope of the implant enabling the child to function in a “hearing world”; that the biggest area of contention is in respect of their childs education; and that parents talked openly about constraints imposed on them by implantation. The vast majority of parents did not regret their decision to proceed with implantation.

A study of the safety and harms of antidepressant drugs for older people: a cohort study using a large primary care database

OBJECTIVES The aim of this study was to establish the relative safety and balance of risks for antidepressant treatment in older people. The study objectives were to (1) determine relative and absolute risks of predefined adverse events in older people with depression, comparing classes of antidepressant drugs [tricyclic and related antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase inhibitors (MAOIs) and other antidepressants] and commonly prescribed individual drugs with non-use of antidepressant drugs; (2) directly compare the risk of adverse events for SSRIs with TCAs; (3) determine associations with dose and duration of antidepressant medication; (4) describe patterns of antidepressant use in older people with depression; and (5) estimate costs of antidepressant medication and primary care visits. DESIGN A cohort study of patients aged 65 years and over diagnosed with depression. SETTING The study was based in 570 general practices in the UK supplying data to the QResearch database. PARTICIPANTS Patients diagnosed with a new episode of depression between the ages of 65 and 100 years, from 1 January 1996 to 31 December 2007. Participants were followed up until 31 December 2008. INTERVENTIONS The exposure of interest was treatment with antidepressant medication. Antidepressant drugs were grouped into the major classes and commonly prescribed individual drugs were identified. MAIN OUTCOME MEASURES There were 13 predefined outcome measures: all-cause mortality, sudden cardiac death, suicide, attempted suicide/self-harm, myocardial infarction, stroke/transient ischaemic attack (TIA), falls, fractures, upper gastrointestinal bleeding, epilepsy/seizures, road traffic accidents, adverse drug reactions and hyponatraemia. RESULTS In total, 60,746 patients were included in the study cohort. Of these, 54,038 (89.0%) received at least one prescription for an antidepressant during follow-up. The associations with the adverse outcomes were significantly different between the classes of antidepressant drugs for seven outcomes. SSRIs were associated with the highest adjusted hazard ratios (HRs) for falls [1.66, 95% confidence interval (CI) 1.58 to 1.73] and hyponatraemia (1.52, 95% CI 1.33 to 1.75), and the group of other antidepressants was associated with the highest HRs for all-cause mortality (1.66, 95% CI 1.56 to 1.77), attempted suicide/self-harm (5.16, 95% CI 3.90 to 6.83), stroke/TIA (1.37, 95% CI 1.22 to 1.55), fracture (1.63, 95% CI 1.45 to 1.83) and epilepsy/seizures (2.24, 95% CI 1.60 to 3.15) compared with when antidepressants were not being used. TCAs did not have the highest HR for any of the outcomes. There were also significantly different associations between the individual drugs for seven outcomes, with trazodone, mirtazapine and venlafaxine associated with the highest rates for several of these outcomes. The mean incremental cost (for all antidepressant prescriptions) ranged between £51.58 (amitriptyline) and £641.18 (venlafaxine) over the 5-year post-diagnosis period. CONCLUSIONS This study found associations between use of antidepressant drugs and a number of adverse events in older people. There was no evidence that SSRIs or drugs in the group of other antidepressants were associated with a reduced risk of any of the adverse outcomes compared with TCAs; however, they may be associated with an increased risk for certain outcomes. Among individual drugs trazodone, mirtazapine and venlafaxine were associated with the highest rates for some outcomes. Indication bias and residual confounding may explain some of the study findings. The risks of prescribing antidepressants need to be weighed against the potential benefits of these drugs. FUNDING The National Institute for Health Research Health Technology Assessment programme.

Equity in health care financing : the case of Malaysia.

BackgroundEquitable financing is a key objective of health care systems. Its importance is evidenced in policy documents, policy statements, the work of health economists and policy analysts. The conventional categorisations of finance sources for health care are taxation, social health insurance, private health insurance and out-of-pocket payments. There are nonetheless increasing variations in the finance sources used to fund health care. An understanding of the equity implications would help policy makers in achieving equitable financing.ObjectiveThe primary purpose of this paper was to comprehensively assess the equity of health care financing in Malaysia, which represents a new country context for the quantitative techniques used. The paper evaluated each of the five financing sources (direct taxes, indirect taxes, contributions to Employee Provident Fund and Social Security Organization, private insurance and out-of-pocket payments) independently, and subsequently by combined the financing sources to evaluate the whole financing system.MethodsCross-sectional analyses were performed on the Household Expenditure Survey Malaysia 1998/99, using Stata statistical software package. In order to assess inequality, progressivity of each finance sources and the whole financing system was measured by Kakwanis progressivity index.ResultsResults showed that Malaysias predominantly tax-financed system was slightly progressive with a Kakwanis progressivity index of 0.186. The net progressive effect was produced by four progressive finance sources (in the decreasing order of direct taxes, private insurance premiums, out-of-pocket payments, contributions to EPF and SOCSO) and a regressive finance source (indirect taxes).ConclusionMalaysias two tier health system, of a heavily subsidised public sector and a user charged private sector, has produced a progressive health financing system. The case of Malaysia exemplifies that policy makers can gain an in depth understanding of the equity impact, in order to help shape health financing strategies for the nation.

Do estimates of cost-utility based on the EQ-5D differ from those based on the mapping of utility scores?

BackgroundMapping has been used to convert scores from condition-specific measures into utility scores, and to produce estimates of cost-effectiveness. We sought to compare the QALY gains, and incremental cost per QALY estimates, predicted on the basis of mapping to those based on actual EQ-5D scores.MethodsIn order to compare 4 different interventions 389 individuals were asked to complete both the EQ-5D and the Western Ontartio and McMaster Universities Osteoarthritis Index (WOMAC) at baseline, 6, 12, and 24 months post-intervention. Using baseline data various mapping models were developed, where WOMAC scores were used to predict the EQ-5D scores. The performance of these models was tested by predicting the EQ-5D post-intervention scores. The preferred model (that with the lowest mean absolute error (MAE)) was used to predict the EQ-5D scores, at all time points, for individuals who had complete WOMAC and EQ-5D data. The mean QALY gain associated with each intervention was calculated, using both actual and predicted EQ-5D scores. These QALY gains, along with previously estimated changes in cost, were also used to estimate the actual and predicted incremental cost per QALY associated with each of the four interventions.ResultsThe EQ-5D and the WOMAC were completed at baseline by 348 individuals, and at all time points by 259 individuals. The MAE in the preferred model was 0.129, and the mean QALY gains for each of the four interventions was predicted to be 0.006, 0.058, 0.058, and 0.136 respectively, compared to the actual mean QALY gains of 0.087, 0.081, 0.120, and 0.149. The most effective intervention was estimated to be associated with an incremental cost per QALY of £6,068, according to our preferred model, compared to £13,154 when actual data was used.ConclusionWe found that actual QALY gains, and incremental cost per QALY estimates, differed from those predicted on the basis of mapping. This suggests that though mapping may be of value in predicting the cost-effectiveness of interventions which have not been evaluated using a utility measure, future studies should be encouraged to include a method of actual utility measurement.Trial registrationCurrent Controlled Trials ISRCTN93206785

A Randomised Controlled Trial of Ion-Exchange Water Softeners for the Treatment of Eczema in Children

In a randomized trial evaluating the effect of installation of ion-exchange water softeners in the households of children with eczema, the researchers found no evidence of improvement in eczema severity as compared to usual care in the study population.

Comparing Cost-Utility Estimates Does the Choice of EQ-5D or SF-6D Matter?

Background:A number of different measures can be used within cost-utility analyses, we compared results according to both the EQ-5D and SF-6D. Methods:A randomized trial was conducted to compare 4 options for people with knee pain. Over the 2 year trial period, the change in cost to health-service was estimated, and both the EQ-5D and SF-6D were used to estimate the change in quality-adjusted life years (QALYs). Using a complete case analysis, the cost-utility (incremental cost-effectiveness ratio [ICER]) of each option, according to both the EQ-5D and SF-6D, was calculated and assessed in relation to the cost-effectiveness threshold of £20,000 per QALY. Results:Of the 389 participants, 247 had complete cost, EQ-5D and SF-6D data. According to the EQ-5D, option 1 had an estimated ICER of £10,815 (compared with option 4), option 2 was dominated by option 1, and option 3 was subject to extended dominance. Conversely, according to the SF-6D, option 3 had an ICER of £9999 (compared with option 4), option 2 had an ICER of £36,883 (compared with option 3), and option 1 was subject to extended dominance. Conclusion:The EQ-5D and SF-6D estimated that different options (1 and 3, respectively) were cost-effective at the £20,000 per QALY threshold, demonstrating that the choice of measure does matter.

Variations in gains in auditory performance from pediatric cochlear implantation.

Objective To investigate variations in gains in auditory performance in children with cochlear implants. Study Design The auditory performance of 98 children was measured with the Category of Auditory Performance survey instrument. All data were collected prospectively. Variables used to explain gain in Category of Auditory Performance were age at implantation, sex, the duration of “untreated” deafness, the year in which implantation occurred, health care inputs, and cause of hearing impairment. The data were analyzed by ordered probabilistic regression analysis. Results Gain in Category of Auditory Performance was observed to be negatively related to age at implantation, the year in which implantation took place, and the number of medical consultations the child received. None of the other variables were significant determinants of gain in Category of Auditory Performance. Conclusion This study demonstrates the value of examining incremental gain from implantation rather than simply examining outcome levels. It was found that pediatric implantation is subject to diminishing returns. This suggests that further relaxation of entry criteria to implant programs should be undertaken only after careful consideration. The study also confirmed that age at implantation is an important determinant of outcomes. Greater gain in Category of Auditory Performance was experienced by those who underwent implantation at a younger age. This finding has implications for screening, as well as for purchasers and providers of implant services, highlighting the importance of responding in a timely fashion to identified need.