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Purpose

There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.

Methods

In 1988–1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured FEV1 and FVC with mortality follow-up data through December 31, 2011. For this survival analysis 7472 persons aged 40 and over with complete data formed the analytic sample.

Results

There were a total of 3554 deaths. Weighted Cox proportional hazards regression revealed an increased hazard ratio in persons with both fixed ratio and lower limit of normal with a low FEV1 (1.79, p < 0.0001), in those with fixed ratio only with a low FEV1 (1.77, p < 0.0001), in those with abnormal fixed ratio only with a normal FEV1 (1.28, p < 0.0001) compared with persons with no airflow obstruction (reference group). These remained significant after adjusting for demographic variables and other confounding variables.

Conclusions

The addition of FEV1 < 80% of predicted increased the prognostic power of the fixed ratio <0.7 and/or below the lower limit of predicted criteria for airway obstruction.  相似文献   
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OBJECTIVES: This study investigated the prognostic importance of measured peak oxygen intake (VO(2peak)) in women with known coronary heart disease referred for outpatient cardiac rehabilitation. BACKGROUND: Exercise capacity is a powerful predictor of prognosis in men with known or suspected coronary disease. Similar findings are described in women, but fewer studies have utilized measured VO(2peak), the most accurate measure of exercise capacity. METHODS: A single-center design took data from 2,380 women, age 59.7 +/- 9.5 years (1,052 myocardial infarctions, 620 coronary bypass procedures, and 708 with proven ischemic heart disease), who underwent cardiorespiratory exercise testing. They were followed for an average of 6.1 +/- 5 years (median 4.5 years, range 0.4 to 25 years) until cardiac and all-cause death. RESULTS: We recorded 95 cardiac deaths and 209 all-cause deaths. Measured VO(2peak) was an independent predictor of risk, values > or =13 ml/kg/min (3.7 multiples of resting metabolic rate) conferring a 50% reduction in cardiac mortality (hazard ratio [HR] 0.5, p = 0.001). Considered as a continuous variable, a 1 ml/kg/min advantage in initial VO(2peak) was associated with a 10% lower cardiac mortality. Adverse predictors were diabetes (HR 2.73, p = 0.0005) and antiarrhythmic therapy (HR 3.93, p = 0.0001). CONCLUSIONS: As in men, measured VO(2peak) is a strong independent predictor of cardiac mortality in women referred for cardiac rehabilitation.  相似文献   
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The CliRpath Excimer Laser System to Enlarge Lumen Openings (CELLO) registry included patients treated with modified excimer laser catheters for the endovascular treatment of peripheral artery disease affecting the superficial femoral artery (SFA) and proximal popliteal artery. The aim of this study was to assess, via intravascular ultrasound (IVUS) the dissections in the vessel wall following treatment with the laser catheters. IVUS grayscale images from the CELLO registry were systematically reviewed for dissections in the treated vessel segments by two investigators. Images from 33 patients; 66 pullbacks (1867 IVUS frames in 2 phases), were successfully matched frame-to-frame to evaluate identical segments of the treated vessels in the two phases; post-2 mm Turbo-Elite laser pilot channel creation and post Turbo-Booster laser atherectomy. Dissections were categorized as; (1) intimal, (2) medial, (3) intramural hematoma, and (4) adventitial according to the ACC Clinical Expert Consensus Document classification of dissections. An average of 57 frames was evaluated per pullback, giving a total of 3734 frames (1867 matched for pre-ablation (post channel creation) and post-ablation phases). Treatments with the modified Excimer laser catheters resulted in a significant increase in lumen area of 5.5?±?3.2-mm2 (95% CI 4.3–6.8, p?<?0.0001) and reduction in plaque plus media volume of ?10.6?±?36.0 mm3 (95% CI ?25.8 to 4.6, p?=?0.1619) whilst giving rise to mainly intramural hematoma formations post Turbo-Booster laser treatment in 55% of frames assessed and 24% medial dissections with less than 1% adventitial disruption. The Excimer laser based Turbo-Booster treatment of peripheral artery lesions resulted in significant plaque debulking and increased lumen diameter with negligible degree of adventitial layer injury.  相似文献   
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Background

The rapid and continuous growth of health care cost aggravates the frequently low priority and less attention given in financing laboratory services. The poorest countries have the highest out-of-pocket spending as a percentage of income. Higher charges might provide a greater potential for revenue. If fees raise quality sufficiently, it can enhance usage. Therefore, estimating the revenue generated from laboratory services could help in capacity building and improved quality service provision.

Methods

Panel study design was used to determine revenue generated from clinical chemistry and hematology services at Tikur Anbessa Specialized Teaching Hospital, Addis Ababa, Ethiopia. Activity-Based Costing (ABC) model was used to determine the true cost of tests performed from October 2011 to December 2011 in the hospital. The principle of Activity-based Costing is that activities consume resources and activities consumed by services which incur the costs and hence service takes the cost of resources. All resources with costs are aggregated with the established casual relationships. The process maps designed was restructured in consultation with the senior staffs working and/or supervising the laboratory and pretested checklists were used for observation. Moreover, office documents, receipts and service bills were used while collecting data. The amount of revenue collected from services was compared with the cost of each subsequent test and the profitability or return on investment (ROI) of services was calculated. Data were collected, entered, cleaned, and analyzed using Microsoft Excel 2007 software program and Statistical Software Package for Social Sciences version 19 (SPSS). Paired sample t test was used to compare the price and cost of each test. P-value less than 0.05 were considered as statistically significant.

Result

A total of 25,654 specimens were analyzed during 3 months of regular working hours. The total numbers of clinical chemistry and hematology tests performed during the study period were 45,959 (66.1 %) and 23,570 (33.9 %), respectively. Only 274, 386 (25.3 %) Ethiopian Birr (ETB) was recovered from the total cost of 1,086,008.09 ETB incurred on clinical chemistry and hematology laboratory tests. The result showed that, about 133,821 (12.32 %) ETB was revenue not collected from out-of-pocket payments that was paid for the services as a result of under pricing. The result showed that 18 out of 20 laboratory tests were under priced. The cost burden related to free Anti Retro-viral Therapy (ART) services was 285,979.82 (26.3 %) ETB.

Conclusion

The cost per test estimated was significantly different to the existing price. About 90 % of the tests were under priced. This information could warn the hospital to reconsider resetting prices of these tests profitability ration less than 1. The revenue collected could help to build capacity, upscale quality, and sustainable service delivery.
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Objective To determine the prevalence of and factors associated with defaulting from antiretroviral treatment (ART) in Jimma, Ethiopia. Methods Unmatched case control study: cases were individuals who had missed two or more clinical appointments (i.e. had not been seen for the last 2 months) between January 2005 and February 2007; controls were individuals who had been on ART at least for 1 year and were rated as excellent adherers by the providers. Data were collected from patient records, and by telephone call and home visit to identify the reason for defaulting. Results Of 1270 patients who started ART, 915 (72.0%) were active ART users and 355 (28.0%) had missed two or more clinical appointments. The latter comprised 173 (13.6%) defaulters, 101 (8.0%) who transferred out, 75 (5.9%) who died, and 6 (0.5%) who restarted ART. Reasons for defaulting were unclear in most cases. Reasons given were loss of hope in medication, lack of food, mental illness, holy water, no money for transport, and other illnesses. Tracing was not successful because of incorrect address on the register in 61.6% of the cases. Taking hard drugs (cocaine, cannabis and IV drugs), excessive alcohol consumption, being bedridden, living outside Jimma town and having an HIV negative or unknown HIV status partner were associated with defaulting ART. Conclusion A significant proportion of patients defaulted from ART treatment. ART clinics should ensure that patients’ addresses are correct and complete. Programmatic and counseling efforts to decrease ART defaulting should address illicit drug and excessive alcohol use, decentralise ART services, institute home‐based treatment options for seriously ill and bedridden patients, and address patients concerns.  相似文献   
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Background

Tuberculosis (TB) disease affects survival among HIV co-infected patients on antiretroviral therapy (ART). Yet, the magnitude of TB disease on mortality is poorly understood.

Methods

Using a prospective cohort of 22,477 adult patients who initiated ART between August 2000 and June 2009 in Uganda, we assessed the effect of active pulmonary TB disease at the initiation of ART on all-cause mortality using a Cox proportional hazards model. Propensity score (PS) matching was used to control for potential confounding. Stratification and covariate adjustment for PS and not PS-based multivariable Cox models were also performed.

Results

A total of 1,609 (7.52%) patients had active pulmonary TB at the start of ART. TB patients had higher proportions of being male, suffering from AIDS-defining illnesses, having World Health Organization (WHO) disease stage III or IV, and having lower CD4 cell counts at baseline (p?<?0.001). The percentages of death during follow-up were 10.47% and 6.38% for patients with and without TB, respectively. The hazard ratio (HR) for mortality comparing TB to non-TB patients using 1,686 PS-matched pairs was 1.37 (95% confidence interval [CI]: 1.08 – 1.75), less marked than the crude estimate (HR?=?1.74, 95% CI: 1.49 – 2.04). The other PS-based methods and not PS-based multivariable Cox model produced similar results.

Conclusions

After controlling for important confounding variables, HIV patients who had TB at the initiation of ART in Uganda had an approximate 37% increased hazard of overall mortality relative to non-TB patients.
  相似文献   
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