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P Dolan

Publications and source records attributed to P Dolan.

At least 55 records · Page 3Linked to original sources
PubMed1998

The cost of treating osteoporotic fractures in the United Kingdom female population.

Osteoporotic fractures represent a significant burden to society. The costs of osteoporotic fractures to the UK health care system have not previously been accurately described. In this paper, we quantify the health care and social care costs of fractures occurring in women aged 50 years and over in the UK. We used a variety of data sources. For acute hospital hip fracture costs existing published estimates were used whilst for social care costs a survey of resource use among fracture patients before and after hip fracture was utilized. We undertook a case-control study using the General Practice Research Database to estimate primary care costs. From these data we estimated that the cost of a hip fracture is about 12,000 Pounds, with non-acute hospital costs representing the larger proportion. The other fractures were less expensive, at 468 Pounds, 479 Pounds and 1338 Pounds for wrist, vertebral and other fractures, respectively. For all fractures the annual cost to the UK is 727 million Pounds. Assuming each male hip fracture costs the same as a female fracture, including these would increase the total costs to 942 million Pounds.

Aged↗
PubMed1998

Asymmetric low back loading in asymmetric lifting movements is not prevented by pelvic twist.

Asymmetric lifting is associated with an increased risk of low back disorders. Especially in lifting movements, characterized by a small amount of asymmetry, it is still the question if asymmetric lumbosacral torques occur, or if subjects try to avoid asymmetric back loading by twisting their pelvis with respect to the feet. An increase of the lifting speed or the box weight might amplify the lumbar torques but might also result in an attempt to limit further increase of asymmetric torques by increasing pelvic twist. In the current study, asymmetrical lifting movements were analyzed with the aid of a 3D linked segment model, using cuffs mounted to the body segments. Eight subjects performed lifting movements with five different asymmetry conditions, ranging from 0 to 90 degrees lifting asymmetry with respect to the sagittal plane, using two lifting speeds and two box weights. A significant increase in lateral flexing and twisting low back torque was found for each increase in asymmetry of the lifting movement. Pelvic twist accounted more or less constantly for about 25% of the lifting asymmetry and was hardly influenced by lifting speed or box weight. Even for 10 or 30 degrees of lifting asymmetry, subjects did not twist their pelvis far enough to avoid asymmetric loading of the low back. Assuming that asymmetric loading of the low back is more strenuous to the spine than symmetric loading, the current results indicate that even small deviations of a lifting movement from the sagittal plane can explain an increased risk of low back disorders.

Back↗
PubMed1998

Repetitive lifting tasks fatigue the back muscles and increase the bending moment acting on the lumbar spine.

During manual handling, the back muscles protect the spine from excessive flexion, but in doing so impose a high compressive force on it. Epidemiological links between back pain and repetitive lifting suggest that fatigued muscles may adversely affect the balance between bending and compression. Fifteen volunteers lifted and lowered a 10 kg weight from floor to waist height 100 times. Throughout this task, the bending moment acting on the osteoligamentous lumbar spine was estimated from continuous measurements of lumbar flexion, obtained using the 3-Space Isotrak. Spinal compression was estimated from the electromyographic (EMG) activity of the erector spinae muscles, recorded from skin-surface electrodes at the levels of T10 and L3. EMG signals were calibrated against force when subjects pulled up on a load cell, and correction factors were applied to account for changes in muscle length and contraction velocity. Fatigue in the erector spinae muscles was quantified by comparing the frequency content of their EMG signal during static contractions performed before, and immediately after, the 100 lifts. Results showed that peak lumbar flexion increased during the 100 lifts from 83.3 +/- 14.8% to 90.4 +/- 14.3%, resulting in a 36% increase in estimated peak bending moment acting on the lumbar spine (P = 0.008). Peak spinal compression fell by 11% (p = 0.007). The median frequency of the EMG signal at L3 decreased by 5.5% following the 100 lifts (p = 0.042) confirming that the erector spinae were fatigued, but measures of fatigue showed no significant correlation with increased bending. We conclude that repetitive lifting induces measurable fatigue in the erector spinae muscles, and substantially increases the bending moment acting on the lumbar spine.

Adult↗
PubMed1998

The measurement of individual utility and social welfare.

It has been suggested by a number of economists that decisions about how to allocate scarce health care resources should be informed by the cost per quality-adjusted life-years (QALYs) of the different alternatives. One of the criticisms of the QALY approach is that it is based on the measurement of individual utility; yet the values elicited are used to inform social choice. In this respect, it is argued that the QALY approach fails to take account of distributional issues that are known to be important in the context of health care. This paper addresses this issue and presents an approach grounded in microeconomic theory that is flexible enough to deal with a wide range of efficiency-equity trade-offs, while making the nature of the trade-off transparent. In addition, it is an approach that is relatively simple to investigate empirically, and the results of a preliminary study are presented as illustration of this.

Budgets↗
PubMed1998

Prescribing by general practitioners after an osteoporotic fracture.

OBJECTIVES: Osteoporosis is a major cause of morbidity and cost. Patients sustaining one osteoporotic fracture are at increased risk of having another fracture. The objective of this study was to examine the use of "bone drugs" for the prevention of further osteoporotic fractures among patients who have had a "typical" osteoporotic fracture. METHODS: This study took a random sample of 300 women aged 50 and over who had sustained either a vertebral, hip or Colles fracture in 1995 from the General Practice Research Database (GPRD) and compared their use of bone drugs with 300 age and practice matched controls. RESULTS: Compared with age and practice matched control patients only vertebral fracture patients showed a statistically significant increase in the use of bone drugs in the year after fracture (39% and 2% for cases and controls respectively; 95% CI of difference 27% to 47%). Etidronate was the most commonly used compound. CONCLUSION: The majority of patients sustaining an osteoporotic fracture are not prescribed any pharmaceutical agents for the secondary prevention of fracture one year after a primary fracture.

Aged↗
PubMed1997

Could sudden increases in physical activity cause degeneration of intervertebral discs?

Epidemiological studies link high repetitive loading of the lower back with degeneration of intervertebral discs, and experiments on cadaver spines confirm that repetitive mechanical loading can disrupt the lumbar discs in a manner characteristic of "degeneration". But why do living discs not just strengthen in response to this stimulus, as other musculo-skeletal tissues do? Our hypothesis proposes that the low metabolic rate of lumbar discs (the largest avascular structures in the body) prevents them from keeping pace with adaptive remodelling changes in adjacent tissues, so that large and abrupt increases in a person's level of physical activity may leave the lumbar discs the weak link in a strengthening and heavily loaded spine. Recent laboratory investigations support the hypothesis, but clinical evidence is required to relate recent disc degeneration with recent increases in physical activity, and so test the hypothesis.

Fatigue↗
PubMed1997

The time trade-off: a note on the effect of lifetime reallocation of consumption and discounting.

This paper considers the extent to which responses to time trade-off (TTO) questions can provide unbiased estimates of ratios of individual marginal rates of substitution (MRS) of wealth for risk of various health state impairments relative to the corresponding MRS for risk of death. It is shown that if there is reallocation of lifetime consumption and/or discounting of future utilities, then a TTO response that is not adjusted for these effects will unambiguously overestimate the ratios of individual MRS. While the effect of reallocation is likely to be very small, discounting can lead to significant overestimation, the magnitude of which depends in part upon the severity of the health state impairment.

Bias↗
PubMed1997

Mapping visual analogue scale health state valuations onto standard gamble and time trade-off values.

Despite becoming increasingly common in evaluations of health care, different methods of quantitatively measuring health status appear to produce different valuations for identical descriptions of health. This paper reports on a study that elicited health state valuations from the general public using three different methods: the visual analogue scale (VAS), the standard gamble (SG) and the time trade-off (TTO). Two variants of the SG and TTO were tested: Props (using specially designed boards and cards); and No Props (using a self-completion booklet). This paper focuses on empirical relationships between health state valuations from the VAS and the (four) other methods. The relationships were estimated using Tobit regression of individual-level data. In contrast to a priori expectations, the mapping functions estimated suggest that differences are more pronounced across variant than across method. Furthermore, relationships with VAS scores are found to depend on the severity of the state: TTO Props valuations are higher than VAS responses for mild states and lower for more severe states; SG Props valuations are broadly similar to VAS scores over a wide range; and No Props responses are consistently higher than VAS valuations, particularly for more severe states. Explanations are proposed for these findings.

Economics, Medical↗
PubMed1997

Valuing health status using VAS and TTO: what lies behind the numbers?

It is well known that different methods of eliciting the valuations attached to various health states, such as the Visual Analogue Scale (VAS) and the Time Trade Off (TTO), yield different results. This study gathers qualitative data from a group of 43 respondents who had previously taken part in a large scale national study which set out to elicit the values attached by individuals to various health states using both the VAS and the TTO techniques. The findings of this study raised three questions which are of particular interest here: (1) Why are some states that are rated better than dead on the VAS often rated as worse than dead in TTO? (2) Why are some respondents unwilling to trade off any time at all in order to avoid a health state that they place below full health on the VAS? (3) Why are TTO valuations of older respondents for the more severe health states lower than those of the younger age groups? This study has uncovered qualitative evidence on each of these three key issues. Regarding the first question, many respondents did not appear to interpret a better than dead VAS score as a strict preference for spending 10 years in a health state over immediate death. Several different factors appeared to contribute towards this, an important one being the tendency of respondents to ignore the duration of the health state during the VAS task. Regarding the second question, there is evidence of the existence of a "threshold of tolerability" below which states would have to fall before some respondents would be willing to give up any time at all on the TTO. Regarding the last question, it appears that older respondents are less likely to find the worse than dead TTO scenario plausible than those in the younger age groups. However, whilst this may explain why older respondents attach lower worse than dead valuations to health states, it does not appear to account for the entire difference in TTO valuations between the two age groups. In addition, it appears that older respondents may be less prepared to live for the next 10 years in a diminished health state.

Adolescent↗
PubMed1997

Correlating clinical indicators of lower-limb ischaemia with quality of life.

The objectives of the study were to analyse the impact of increasing lower-limb ischaemia upon quality of life and to assess the correlation between clinical indicators of lower-limb ischaemia and such quality. A prospective observational study of a consecutive series of 235 patients (144 men and 91 women; median age 68 (range 41-87) years presenting with varying degrees of lower-limb ischaemia graded according to ISCVS criteria was performed. Data was collected at interview before any intervention. Clinical indicators of lower-limb perfusion included: intermittent claudication and maximum walking distance on standardized treadmill testing; ankle:brachial pressure indices and isotope limb blood flow. Quality of life analysis was performed using the EuroQol (EQ) questionnaire. This is a standardized generic instrument for describing health-related quality of life and consists of a descriptive system of five dimensions, each measured on three levels. Thus, a profile and two single indices of quality of life were derived using different methods. Increasing lower-limb ischaemia results in a statistically significant deterioration in both global quality of life and in all EQ-measured quality of life dimensions (P < 0.01 Kruskal-Wallis, ANOVA). The correlation between clinical indicators and quality of life is statistically significant but not sufficiently close (correlation coefficients < 0.6) to assume that variations in clinical indicators result in reciprocal variations in quality of life. In conclusion, as might be expected, a significant correlation exists between clinical indicators of lower-limb ischaemia and health-related quality of life. However, the low correlation coefficients emphasize how tenuous the association is. Thus, a significant improvement in the clinical indicators of lower-limb ischaemia cannot be assumed to impart a similar benefit on quality of life. The latter concept must therefore be analysed independently.

Activities of Daily Living↗
PubMed1997

Quality of life analysis in patients with lower limb ischaemia: suggestions for European standardisation.

INTRODUCTION AND OBJECTIVES: In this era of evidence-based medicine and limited resources we seem obliged, on clinical and economic grounds, to demonstrate that we improve not only patient survival but also the quality of patients' lives. This study aims to determine the impact of increasing lower limb ischaemia on quality of life (QOL) and which of three commonly used generic QOL instruments is the most valid, reliable, and responsive to change in patients with lower limb ischaemia. PATIENTS AND METHODS: Two hundred and thirty-five patients, 144 men and 91 women, median age 68 years (range 41-87 years) were graded according to ISCVS suggested reporting standards, i.e. 16 mild, 116 moderate and 25 severe claudicants; 33 patients had rest pain and 45 tissue loss. Patients completed Short Form 36 (SF36), EuroQol (EQ-5D) and Nottingham Health Profile (NHP) questionnaires at interview. Additional copies of questionnaires were posted to 80 patients prior to attendance. Correlation between the two sets of responses reflects test-retest reliability. Correlation between domains measured by the three instruments reflects convergent and divergent validity. Kruskal Wallis ANOVA detected QOL changes across the whole group. Spearman Rank was used to analyse validity and reliability. Responsiveness was analysed using the Mann-Whitney U-test. RESULTS: Increasing lower limb ischaemia confers significant (p < 0.05) deterioration in: SF36 measured: physical functioning, physical role, pain, general health, vitality, social functioning and mental health. EQ-5D measured: mobility, self-care, usual activities, pain and anxiety/depression. NHP measured: energy, pain, emotional reaction, sleep, social isolation and physical mobility. All three instruments are significantly reliable (rs > 0.7). The validity of SF36 and NHP (rs = 0.68-0.78) is superior to EQ-5D (rs = 0.37-0.7). SF36 & NHP are equally responsive to changes in physical activity and pain. SF36 and EQ-5D are most responsive to changes in social activity. SF36 is most responsive to changes in psychological status. CONCLUSIONS: QOL deteriorates markedly with increasing lower limb ischaemia. The SF36 would appear to be the most appropriate generic QOL analysis tool for these patients. We recommend its widespread adoption throughout Europe, thus providing a standardised tool for reporting generic QOL.

Activities of Daily Living↗
PubMed1997

Modeling valuations for EuroQol health states.

OBJECTIVES: It has become increasingly common for preference-based measures of health-related quality of life to be used in the evaluation of different health-care interventions. For one such measure, The EuroQol, designed to be used for these purposes, it was necessary to derive a single index value for each of the 243 health states it generates. The problem was that it was virtually impossible to generate direct valuations for all of these states, and thus it was necessary to find a procedure that allows the valuations of all EuroQol states to be interpolated from direct valuations on a subset of these. METHODS: In a recent study, direct valuations were elicited for 42 EuroQol health states (using the time trade-off method) from a representative sample of the UK population. This article reports on the methodology that was adopted to build up a "tariff" of EuroQol values from this data. RESULTS: A parsimonious model that fits the data well was defined as one in which valuations were explained in terms of the level of severity associated with each dimension, an intercept associated with any move away from full health, and a term that picked up whether any dimension in the state was at its most severe level. CONCLUSIONS: The model presented in this article appears to predict the values of the states for which there are direct observations and, thus, can be used to interpolate values for the states for which no direct observations exist.

Activities of Daily Living↗
PubMed1997

Treatment of a giant haemangioma of the liver with Kasabach-Merritt syndrome by orthotopic liver transplant a case report.

We describe a case of giant cavernous haemangioma of the liver with disseminated intravascular coagulopathy (Kasabach-Merritt syndrome) which was cured by orthotopic liver transplant. A 47 year old man presented with bleeding and tender massive hepatomegaly after tooth extraction. Investigations showed disseminated intravascular coagulopathy and a giant hepatic haemangioma involving both lobes of the liver. Initial treatment failed to resolve the coagulopathy and liver resection was attempted. At laparotomy the tumour was unresectable and the only option for cure was to offer a liver transplantation. The orthotopic liver transplant was performed 20 days after initial laparotomy. Subsequently, all coagulation parameters returned to normal and the patient remains well after 12 months. Orthotopic liver transplant can be considered for giant hepatic haemangioma with Kasabach-Merritt syndrome when resection is necessary and a partial hepatectomy is not technically feasible.

Disseminated Intravascular Coagulation↗
PubMed1997

Aggregating health state valuations.

It is now recognized that preference-based measures of health status have an important role to play in determining priorities in health care. A number of methodological and ethical issues have been raised, but one that has as yet received little attention is the question of how individual responses should be aggregated when attempting to express the valuations of a given group. In a recent study of over 3000 members of the British general public, valuations were elicited for health states defined in terms of the EuroQol Descriptive System using the time trade-off method. A EuroQol 'tariff' of valuations has been generated which, because of the methodology employed, provides a good approximation of mean values. The purpose of this paper is to present a tariff based on median values. The nature of the distributions of values results in a median-based tariff which, compared to the mean-based one, has higher values for less severe states and lower values for more severe states. This is likely to have important implications for resource allocation decisions.

Activities of Daily Living↗
PubMed1997

The use of surface EMG power spectral analysis in the evaluation of back muscle function.

The rate of decline in the median frequency (MF) of the surface EMG power spectrum (MFgrad) has been evaluated for its use in monitoring the fatigability of the erector spinae muscles during the performance of submaximal isometric contractions. MFgrad consistently displayed a highly significant relationship with endurance time for the task (p < 0.05), giving a slightly better correlation for contractions performed in lordotic postures, with the back muscles in a shortened position, than in flexed postures. No significant difference existed between mean MFgrad values recorded from the right and left erector spinae muscles, at either thoracic or lumbar levels. The back extensor muscles of men were more fatigable than those of women, and this has been discussed in relation to corresponding differences in muscle fiber type relative size. Greater erector spinae muscle fatigability was associated with both the existence of, and the risk of developing, serious low back pain. Possible mechanisms for the association, from retrospective and prospective points of view, have been advanced.

Analysis of Variance↗