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991.

Background

The assessment of the impact of healthcare interventions may help commissioners of healthcare services to make optimal decisions. This can be particularly the case if the impact assessment relates to specific patient populations and uses timely local data. We examined the potential impact on readmissions and mortality of specialist heart failure services capable of delivering treatments such as b-blockers and Nurse-Led Educational Intervention (N-LEI).

Methods

Statistical modelling of prevented or postponed events among previously hospitalised patients, using estimates of: treatment uptake and contraindications (based on local audit data); treatment effectiveness and intolerance (based on literature); and annual number of hospitalization per patient and annual risk of death (based on routine data).

Results

Optimal treatment uptake among eligible but untreated patients would over one year prevent or postpone 11% of all expected readmissions and 18% of all expected deaths for spironolactone, 13% of all expected readmisisons and 22% of all expected deaths for b-blockers (carvedilol) and 20% of all expected readmissions and an uncertain number of deaths for N-LEI. Optimal combined treatment uptake for all three interventions during one year among all eligible but untreated patients would prevent or postpone 37% of all expected readmissions and a minimum of 36% of all expected deaths.

Conclusion

In a population of previously hospitalised patients with low previous uptake of b-blockers and no uptake of N-LEI, optimal combined uptake of interventions through specialist heart failure services can potentially help prevent or postpone approximately four times as many readmissions and a minimum of twice as many deaths compared with simply optimising uptake of spironolactone (not necessarily requiring specialist services). Examination of the impact of different heart failure interventions can inform rational planning of relevant healthcare services.  相似文献   
992.
993.
994.
A characteristic feature of patient satisfaction research is the consistently high level of satisfaction recorded. More reliable and relevant inquiry tools are constantly being developed, but underlying psychological and social pressures that could promote such a consistent and undiscriminating response have been little investigated. Williams et al. (1998) explored the phenomenon and concluded that, by considering issues of duty and culpability, patients could make allowances for poor care, and avoid evaluating it negatively. Their study was in community mental health. This study follows up their work within elective orthopaedic surgery, and investigates the pressures promoting such apparent transformation of opinion. Using a longitudinal design, and in-depth qualitative interviews, the patient's process of reflection was explored. Three psycho-social pressures were identified that appear to work together to make the transformation of opinion almost the default process. They are: the relative dependency of patients within the healthcare system; their need to maintain constructive working relationships with those providing their care; and their general preference for holding a positive outlook. It is suggested that, while it is the patient's prerogative to re-interpret the quality of their care positively, it is not the prerogative of the inquirer to accept this re-interpretation as representative of the patient's experience. Methods of inquiry are needed which access something of patients' development of opinion, and thereby something of their initial, often more negative, untransformed responses to their healthcare experiences.  相似文献   
995.
PURPOSE: To evaluate surveillance methods in a pilot epidemiological study of contact lens related microbial keratitis (MK) cases identified by ophthalmic practitioners in Australia and New Zealand between May and August 2003 inclusive. METHODS: Twelve ophthalmologists and 55 optometrists from rural and metropolitan locations were sent a study information pack with postal reporting forms. After 2 months, practitioners were emailed a link to a website for Internet reporting. After 4 months, practitioners were prompted by email and then by telephone if a response was not received. Passive response rates were the rate of returns after posting information and emailing the website link. Active response rates included personalized email and telephone follow-up. RESULTS: Ten cases of MK were identified by optometrists and five by ophthalmologists. The passive response rates were 79% and 58% for the first and second reporting periods, respectively. There was a lower response rate in the second reporting period compared to the first (P = 0.02). With active surveillance the response rate increased to 97% and 96%. A large proportion of optometrists (62%) and ophthalmologists (55%) used the website for at least one reporting period. Internet reporting was used by all New Zealand practitioners (5/5). CONCLUSIONS: A surveillance study to estimate the incidence of contact lens related MK in Australia and New Zealand is feasible and acceptable. Internet-based reporting offers a reliable, rapid and cost-effective means of running a large scale, international surveillance study. Active surveillance methods are necessary to enhance reporting rates.  相似文献   
996.
The relative oral bioavailability (BA) of halofantrine base (Hf) was assessed in male beagle dogs after administration of a medium chain triglyceride (MCT), a long chain triglyceride (LCT), and a blended LCT/MCT lipid solution formulation of Hf (Study 1) and after administration of suspensions of Hf base and Hf. HCl in LCT (Study 2). A series of in vitro lipid digestion experiments were also performed in an attempt to clarify the data obtained. In vitro drug solubilization profiles were markedly dependent on the mass of lipid employed in lipid digestion experiments. At high lipid masses ( approximately 25 mg triglyceride/mL), MCT formulations gave maximal benefit, whereas at low lipid concentrations ( approximately 5 mg triglyceride/mL), LCT formulations provided improved solubilization capacity. The in vitro digestion and solubilization data at lower lipid masses were consistent with the in vivo data where the BA of Hf after oral administration of the LCT solution > LCT/MCT blend > MCT solution. The second BA study showed similar, albeit variable, exposure after oral administration of a suspension of Hf base or Hf. HCl in LCT and this trend was broadly consistent with in vitro results. This study demonstrates the potential utility of in vitro digestion models to assess and rank order the in vivo performance of lipid solution and suspension formulations of poorly water-soluble drugs such as Hf.  相似文献   
997.
The aim of this paper is to compare a service offering genetic testing and presymptomatic surveillance to women at increased risk of developing breast cancer with its predecessor of no service at all in terms of survival and quality-adjusted survival (QALYs) by means of a Markov cohort chain simulation model. Genetic assessment and presymptomatic care provided between 0.07-1.61 mean additional life years and 0.05-1.67 mean QALYs over no services. Prophylactic surgery and surveillance extended mean life expectancy by 0.41-1.61 and 0.32-0.99 years, respectively over no services for high-risk women. Model outcomes were sensitive to all the parameters varied in the sensitivity analysis. Providing cancer genetic services increase survival and as long as services do not induce adverse psychological effects they also provide more QALYs. The greatest survival and QALY benefits were found for women with identified mutations. As more cancer genes are identified, the survival and cost-effectiveness of genetic services will improve. Although mastectomy provided most additional life years, when quality of life was accounted for oophorectomy was the optimal strategy. Delayed entry into coordinated genetic services was found to diminish the average survival and QALY gains for a woman utilising these services.  相似文献   
998.
Prospective comparison of D1 vs modified D2 gastrectomy for carcinoma   总被引:18,自引:0,他引:18  
To compare the outcomes after D1 gastrectomy with those after modified D2 gastrectomy (preserving pancreas and spleen) performed by specialist surgeons for gastric cancer in a large UK NHS Trust. In all, 118 consecutive patients with gastric adenocarcinoma were referred by postcode, to undergo either a D1 gastrectomy (North Gwent (RJ), n=36, median age 76 years, 21 m) or a modified D2 gastrectomy (South Gwent (WL), n=82, 70 years, 57 m). Operative mortality in the two groups of patients was similar (D1 8.3% vs D2 7.3%, chi2 0.286, DF 1, P=0.593). Overall cumulative survival at 5 years was 32% after D1 gastrectomy compared to 59% after D2 gastrectomy (chi2 4.25, DF 1, P=0.0392). In patients with stage III cancers, survival was 8% after D1, compared with 33% after D2 gastrectomy (chi2 6.43, DF 1, P=0.0112). In a multivariate analysis, T stage (hazard ratio 2.339, 95% CI 1.683-2.995, P=0.01), N stage (hazard ratio 4.026, 95% CI 3.536-4.516, P=0.0001) and the extent of lymphadenectomy (hazard ratio 0.258, 95% CI -0.426-0.942, P=0.0001) were independently associated with durations of survival. In conclusion, modified D2 gastrectomy can improve survival four-fold for patients with stage III gastric cancer, without significantly increasing morbidity and mortality when compared with a D1 gastrectomy.  相似文献   
999.
The risk of prostate cancer is known to be elevated in carriers of germline mutations in BRCA2, and possibly also in carriers of BRCA1 and CHEK2 mutations. These genes are components of the ATM-dependent DNA damage signalling pathways. To evaluate the hypothesis that variants in ATM itself might be associated with prostate cancer risk, we genotyped five ATM variants in DNA from 637 prostate cancer patients and 445 controls with no family history of cancer. No significant differences in the frequency of the variant alleles at 5557G>A (D1853N), 5558A>T (D1853V), ivs38-8t>c and ivs38-15g>c were found between the cases and controls. The 3161G (P1054R) variant allele was, however, significantly associated with an increased risk of developing prostate cancer (any G vs CC OR 2.13, 95% CI 1.17-3.87, P=0.016). A lymphoblastoid cell line carrying both the 3161G and the 2572C (858L) variant in the homozygote state shows a cell cycle progression profile after exposure to ionising radiation that is significantly different to that seen in cell lines carrying a wild-type ATM gene. These results provide evidence that the presence of common variants in the ATM gene, may confer an altered cellular phenotype, and that the ATM 3161C>G variant might be associated with prostate cancer risk.  相似文献   
1000.
Metastasis is a major factor associated with poor prognosis in cancer, but little is known of its molecular mechanisms. Although the clinical behavior of soft tissue sarcomas is highly variable, few reliable determinants of outcome have been identified. New markers that predict clinical outcome, in particular the ability of primary tumors to develop metastatic tumors, are urgently needed. Here, we have chosen leiomyosarcoma as a model for examining the relationship between gene expression profile and the development of metastasis in soft tissue sarcomas. Using cDNA microarray, we have identified a gene expression signature associated with metastasis in sarcoma that allowed prediction of the future development of metastases of primary tumors (Kaplan-Meier analysis P = 0.001). Our finding may aid the tailoring of therapy for individual sarcoma patients, where the aggressiveness of treatment is affected by the predicted outcome of disease.  相似文献   
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