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K McPherson

Publications and source records attributed to K McPherson.

At least 91 records · Page 5Linked to original sources
PubMed1996

Hormone replacement therapy in a risk-benefit perspective.

The relative cost-effectiveness of different treatment strategies for hormone replacement therapy (HRT) was assessed within the framework of a computer model. Where data were lacking, it was necessary to make assumptions about the effects of HRT, particularly in relation to combined oestrogen-progestogen therapy and cardiovascular disease; however, sensitivity analyses were performed to assess the impact of changing these assumptions on the cost-effectiveness equation. It appears that net expenditure by the NHS will depend critically on the direct costs of treatment, rather than on any indirect costs incurred or saved as a result of side-effects. In terms of mortality, a reduction in cardiovascular disease risk would have greatest impact and would overshadow any small increase in breast cancer risk which may be associated with long-term use. If the cardioprotective effect of oestrogen is real, our results suggest that long-term prophylactic treatment of hysterectomised women would be relatively cost-effective. Treatment of symptomatic menopausal women for any period of time appears to offer very good value for money. The lack of data relating to combined oestrogen-progestogen therapy and cardioprotection, and the major importance of the latter in the equation of benefits and risks, make it more difficult to draw conclusions about the cost-effectiveness of treating non-hysterectomised asymptomatic women for prophylactic reasons.

Aged↗
PubMed1996

The effect of prostatectomy on symptom severity and quality of life.

OBJECTIVE: To determine the effectiveness of prostatectomy in reducing symptom severity and bother and in improving disease-specific and general quality of life. PATIENTS AND METHODS: A prospective, cohort study was performed in National Health Service and private hospitals in the Northern, Wessex, Mersey, and South-West Thames Health Regions which comprised 5276 men undergoing prostatectomy recruited by 101 of the 106 (96%) surgeons (specialist and non-specialist) performing prostatectomy during a 6-month period. Patients were assessed using the American Urological Association (AUA) Symptom Index Score, the AUA symptom bother score, disease-specific and generic quality-of-life scores, the occurrence of adverse events (urinary incontinence, erectile impotence and retrograde ejaculation) and three global (general) questions on the results of their treatment. The outcome was assessed 3 months after surgery. RESULTS: Prostatectomy was effective in reducing both symptoms (initial mean score 20.1 reduced to 7.4, P < 0.001) and symptom bother (initial mean score 14.4 reduced to 4.3, P < 0.001). Not all men experienced a good reduction in symptoms; 121 (3.9%) were worse, 301 (9.6%) were the same, and 721 (23%) experienced only slight improvement. The type of operation, grade of principal operator and use of pre-operative investigations were not associated with the extent of symptomatic improvement. Changes in symptom severity were highly correlated with changes in bothersomeness++ and disease-specific quality of life but not with generic quality of life. A third of men who were continent before surgery reported some incontinence 3 months later, although only 6% found it a problem. Two-thirds of men experienced retrograde ejaculation and 31% experienced some erectile impotence following surgery. CONCLUSIONS: Prostatectomy is effective in reducing symptoms in most men. Men who experience a substantial reduction in symptoms were more likely to report a favourable outcome. The study confirmed that approximately one-third of men reported an unfavourable result 3 months after their operation.

Aged↗
PubMed1996

Endovascular grafting of abdominal aortic aneurysms. A preliminary study.

OBJECTIVE: The authors report the experience of a single investigational center involving two Phase I and a Phase II clinical trials approved by the Food and Drug Administration (FDA) for the transfemoral implantation of woven Dacron grafts for abdominal aortic aneurysms. SUMMARY BACKGROUND DATA: In 1993, EndoVascular Technologies, Inc. ([EVT]; Menlo Park, CA), began an FDA-approved clinical trial of repair of abdominal aortic aneurysms by transfemoral placement of a tube endograft. Subsequently, a bifurcated endograft trial was started. This the first single institution report using the EVT endograft for both tube and bifurcated aortic replacement. METHODS: Seventeen patients were enrolled in two Phase I and one Phase II clinical trials. The Phase I tube graft trial and the Phase I bifurcated graft trial were nonrandomized studies. The Phase II tube graft trial consisted of a randomized prospective control trial of open endoaneurysmorrhaphy versus transfemoral placement of an endograft. RESULTS: Seventeen patients were enrolled in the trial. The graft was placed successfully in all but one patient. Five patients randomized to open procedure and one declined to participate. Eleven patients with endografts are available for follow-up. One graft has been explanted for attachment system migration. One patient is a late failure because of persistent filling of the aneurysm sac. CONCLUSION: Transfemoral placement of an endovascular graft is a viable and effective treatment of abdominal aortic aneurysms in the short term. Use of a bifurcated endograft will open the procedure to more patients. The ideal attachment system and graft material await long-term implantation follow-up.

Adult↗
PubMed1996

Response of women aged 65-74 to invitation for screening for breast cancer by mammography: a pilot study in London, UK.

OBJECTIVE: To investigate the response and benefits to be gained from mammographic screening for breast cancer in women aged 65-74, who are not normally invited for screening. DESIGN: This was a pilot study comprising women aged 65-74 who are not currently invited for routine screening under the NHS breast screening programme. The results from this study were compared with the results of routinely screened women (aged 50-64) from the same health district. SETTING: A mobile breast screening unit in the grounds of the Royal Free Hospital. SUBJECTS: These comprised 5004 women aged 65-74 registered with GPs in the district of Hampstead and on the family health services authority (FHSA) lists. A total of 168 (3.4%) were initially excluded by the general practitioner or FHSA, and 286 (5.9%) of the invitation letters were returned by the Post Office or by other people as not deliverable for some reason. MAIN OUTCOME MEASURES: Response rates to the invitation were assessed using three indices: crude population coverage rate, crude invited population coverage rate, and corrected invited population coverage rate. RESULTS: With regard to response rates, 1684 women aged 65-74 (37% of all those invited, excluding those who were not available) were screened, compared with 2894 (42%) women aged 50-64. The three response rates were higher for younger women than older: the crude population coverage rate was 37.1%, the crude invited population coverage rate was 38.9%, and the corrected invited population coverage rate was 42.1% for women aged 50-64, compared with 32.9%, 34.4%, and 36.8% respectively for women aged 65-69 and 34.3%, 35.2%, and 37.2% for women aged 70-74. The rate of assessment increased significantly with increasing age, with 3.18% of the 50-64 population screened being assessed, as compared with 4.14% and 4.83% of the women aged 65-69 and 70-74, respectively. Most biopsies done in the older women gave positive results, as did the biopsies from the 50-64 age group. However, the biopsy rate increased significantly with increasing age. The cancer detection rates in the women aged 65-69 and 70-74 were 14.2/1000 and 13.2/1000 compared with an incident screening round rate of 4.5/1000 in women aged 50-64. CONCLUSIONS: These results show that there is potential for similar attendance at routine screening by older women if they are invited in the same way as younger women. As the assessment, biopsy, and cancer detection rates in the older women are significantly higher than in the 50-64 year olds, the costs and benefits of including them in the NHS screening programme should be reassessed.

Age Factors↗
PubMed1996

Long-term comparison of Charnley and Stanmore design total hip replacements.

We reviewed the records of the long-term outcome of 208 Charnley and 982 Stanmore total hip replacements (THR) performed by or under the supervision of one surgeon from 1973 to 1987. The Stanmore implant had a better survival rate before revision at 14 years (86% to 79%, p = 0.004), but the difference only became apparent at ten years. The later Stanmore implants did better than the early ones (97% to 92% at ten years, p = 0.005), the improvement coinciding with the introduction of a new cementing technique using a gun. Most of the Charnley implants were done before most of the Stanmore implants so that the difference between the results may in part be explained by improved methods, but this is not the complete explanation since a difference persisted for implants carried out during the same period of time. We conclude that improved techniques have reduced failure rates substantially. This improvement was much greater than that observed between these two designs of implant. Proof of the difference would require a very large randomised controlled trial over a ten-year period.

Bone Cements↗
PubMed1995

Utilisation of hormone replacement therapy by women doctors.

OBJECTIVES: To ascertain the prevalence and duration of use of hormone replacement therapy by menopausal women doctors. DESIGN: Postal questionnaire. SETTING: General practices in the United Kingdom. SUBJECTS: Randomised stratified sample of women doctors who obtained full registration between 1952 and 1976, taken from the current principal list of the Medical Register. MAIN OUTCOME MEASURES: Prevalence and duration of use of hormone replacement therapy; menopausal status. RESULTS: Overall, 45.7% (436/954) of women doctors aged between 45 and 65 years had ever used hormone replacement therapy. When the results from women still menstruating regularly were excluded, 55.2% (428) were ever users and 41.2% (319) current users. The cumulative probability of remaining on hormone replacement therapy was 0.707 at five years and 0.576 at 10 years. CONCLUSIONS: Women doctors have a higher prevalence of use of hormone replacement therapy than has been reported for other women in the United Kingdom, and most users seem to be taking hormone replacement therapy for more than five years. The results may become generalisable to the wider population as information on the potential benefits of hormone replacement therapy is disseminated.

Adult↗
PubMed1995

The National Prostatectomy Audit: the clinical management of patients during hospital admission.

OBJECTIVE: To determine everyday practice in the hospital management of men undergoing prostatectomy and the extent of its variation. PATIENTS AND METHODS: A total of 5361 patients, who represented 89% of all those undergoing prostatic procedures in four health regions (Mersey, Wessex, Northern and South West Thames) and one test site (within Trent) were recruited by 103 (97%) surgeons. Clinical information was collected on a pre-coded data collection form which was completed during the hospital stay by the principal operator. Patient identification occurred at the time of surgery. RESULTS: Important findings included: (i) both older men and those of higher social class were more likely to undergo prostatectomy with fewer symptoms; (ii) men who waited longer for surgery had worse symptoms by the time of their operation; (iii) there were unexplained differences in routine pre- and post-operative investigation and treatment. Half the men had their flow rate or residual urine measured as part of their pre-operative assessment. About half the men received prophylactic antibiotics; (iv) when large groups were analysed, a consistent proportion of men throughout the study (12%) were undergoing the operation for a second time. The clinical course of men having a repeat operation differed in many ways from those having a first time procedure; (v) the larger proportion of men (62%) had surgery for strong indications as opposed to symptoms alone; (vi) although most operations were performed by consultants, emergency admissions, though symptomatically more severe and sicker, were more likely to be operated on by trainee surgeons; (vii) significant variation in mean pre-operative symptom severity and bother scores were seen between surgeons. CONCLUSION: The clinical management of prostatectomy has been defined in a large and representative UK sample. In some circumstances consistent variations have been identified. It is not yet clear whether these variations influence outcome. These data can be used by surgeons wishing to compare their own patient management with that described here.

Age Factors↗
PubMed1995

Emergency appendicectomy and meat consumption in the UK.

STUDY OBJECTIVE: To compare the rates of reported emergency appendicectomies in a cohort study of vegetarians and non-vegetarians by participants' history of meat consumption. DESIGN: This was a prospective cohort study in which participants were asked about their lifetime history of meat consumption/avoidance and, separately, whether they had had an appendicectomy. Appendicectomy was described as either "emergency" or "non-emergency" according to details supplied by the participant. SETTING: The United Kingdom. PARTICIPANTS: These comprised more than 11000 people, of whom 4852 (44%) completed both an appendicectomy form and a dietary questionnaire giving details of their lifetime history of meat consumption. MAIN RESULTS: The percentage who reported an emergency appendicectomy was higher among lifelong meat eaters (10.7%) than either lifelong non-meat eaters (7.8%) or those who had stopped eating meat (8.0%); and the operations were performed at an earlier age in this first group (mean values 18.9, 26.0, and 19.6 years respectively). The overall age adjusted emergency participants who did not eat mean with those who ate meat was 0.47 (95% confidence interval 0.35, 0.65). CONCLUSION: The results suggests that people who do not eat meat have a 50% lower risk of requiring an emergency appendicectomy than those who do. The data do not, however, allow the reliable testing of other hypotheses, so meat consumption may simply be a marker for another dietary, lifestyle, or socioeconomic factor.

Aged↗
PubMed1995

The feasibility and cost of a large multicentre audit of process and outcome of prostatectomy.

Objective--To determine the feasibility of performing multicentre process and outcome audits of common interventions taking prostatic procedures as an example. Design--Prospective, cohort study. Setting--All National Health Service and independent hospitals in Northern, Wessex, Mersey, and South West Thames health regions. Patients--5361 men undergoing prostatectomy identified by 103 of the 107 urologists and general surgeons performing prostatectomy in the study regions. Main measures-- Rates of participation by surgeons and patients; completeness of clinical data provided by surgeons; patient response rate and completeness of patient derived data; and cost. Results--Most surgeons (103,96%) agreed to participate. Overall, the proportion of eligible patients invited to take part was high (89%), although this was only measured in South West Thames, where dedicated data collectors were employed. Few men (80, 1.5%) declined to participate. Of those surviving for three months after surgery, 82.4% (4226) completed and returned the postal questionnaire. The response rate was higher in South West Thames (86.7%) than in the other regions (80.6%-80.8%). The audit was well received: 91% of patients found the questionnaire easy to complete and only 2.3% of them disapproved. Completeness of data was high with both the hospital and patient questionnaires. Missing data occurred in less than 5% of responses to most questions. The attributable cost was 34.50 pounds per patient identified or 44 pounds for patients in whom either the treatment outcome or vital status was known three months after their prostatectomy. Conclusions--This multicentre audit of process and outcome of prostatectomy proved feasible in terms of surgeon participation, patient identification, and the quantity and quality of data collection. Whether the cost was warranted will depend on how surgeons use the audit data to modify their practice.

Aged↗
PubMed1994

Risk of death from cancer and ischaemic heart disease in meat and non-meat eaters.

OBJECTIVE: To investigate the health consequences of a vegetarian diet by examining the 12 year mortality of non-meat eaters and meat eating controls. DESIGN: Prospective observational study in which members of the non-meat eating cohort were asked to nominate friends or relatives as controls. SETTING: United Kingdom. SUBJECTS: 6115 non-meat eaters identified through the Vegetarian Society of the United Kingdom and the news media (mean (SD) age 38.7 (16.8) years) and 5015 controls who were meat eaters (39.3 (15.4) years). MAIN OUTCOME MEASURES: Standardised mortality ratios for cancer, ischaemic heart disease, and total mortality in the two cohorts and death rate ratio in the non-meat eaters compared with meat eaters after adjustment for potentially confounding variables. RESULTS: Standardised mortality ratios (taking the value among the general population as 100) for ischaemic heart disease were 51 (95% confidence interval 38 to 66) for meat eaters and 28 (20 to 38) for non-meat eaters (P < 0.01). Values for all cancers were 80 (64 to 98) and 50 (39 to 62) for meat eaters and non-meat eaters respectively. After adjustment for the effects of smoking, body mass index, and socioeconomic status death rate ratios in non-meat eaters compared with meat eaters were 0.72 (0.47 to 1.10) for ischaemic heart disease and 0.61 (0.44 to 0.84) for all cancers. CONCLUSIONS: The reduced mortality from cancer among those not eating meat is not explained by lifestyle related risk factors, which have a low prevalence among vegetarians. No firm conclusion can be made about deaths from ischaemic heart disease. These data do not justify advice to exclude meat from the diet since there are several attributes of a vegetarian diet apart from not eating meat which might reduce the risk.

Adult↗
PubMed1994

Intensive Care Society's Acute Physiology and Chronic Health Evaluation (APACHE II) study in Britain and Ireland: a prospective, multicenter, cohort study comparing two methods for predicting outcome for adult intensive care patients.

OBJECTIVE: To compare the ability of two methods--Acute Physiology and Chronic Health Evaluation (APACHE II) and Mortality Prediction Model (MPM)--to predict hospital outcome for a large group of intensive care patients from Britain and Ireland. DESIGN: Prospective, multicenter, cohort study. SETTING: Twenty-six general intensive care units in Britain and Ireland. PATIENTS: A total of 8,724 patients admitted to the study. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Probabilities of hospital death for patients were estimated by applying APACHE II and MPM. Predicted risks of hospital death were compared with observed outcomes using four methods of assessing the overall goodness of fit. APACHE II performed better than MPM; the calibration curve for APACHE II lay closer to the line of perfect predictive ability. Lemeshow-Hosmer chi-square statistics were 81 and 57 for APACHE II, and 2515 and 1737 for MPM. The overall correct classification rate for APACHE II was 79%, and this classification rate was 74% for MPM, applying a decision criterion of 50%. The area under the receiver operating characteristic curve was 0.83 with APACHE II and 0.74 with MPM. Even after modifications to the MPM for the assessment of coma, the performance of APACHE II was superior. CONCLUSIONS: APACHE II demonstrated a higher degree of overall goodness of fit, which was superior to MPM for groups of intensive care patients from Britain and Ireland.

Adult↗