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31.

Summary

This study provides evidence that a number of frailty-related characteristics (older age, de novo admission to long-term care (LTC), comorbidities [Charlson Index, osteoporosis, osteoporosis risk factors, sarcopenia risk factors, and dementia]) have increased in the hip fracture population from 2001–2008. This will have significant impact on community resources, as the number of people discharged to the community is also increasing.

Introduction

The aim of this study is to estimate secular changes in the prevalence of selected frailty-related characteristics among the hip fracture population in the Canadian province of Quebec (2001–2008) and the potential impact of these changes on healthcare services.

Methods

The Quebec hospitalization database was used to identify nontraumatic hip fractures for the purposes of calculating age- and sex-specific rates. Also estimated were time trends for selected frailty-related characteristics and discharge destinations.

Results

A significant decline in fracture rates was evident for all age groups except for those <65; sex differences were also observed. Almost all frailty-related characteristics increased over time, ranging from 2 to 14 % per year, which translates to an estimated increase from 16 to 112 %, over the study period. For those whose prior living arrangement was LTC, rates of hip fractures declined significantly (women OR?=?0.93, 0.91–0.95; men OR?=?0.97, 0.94–0.99). In-hospital mortality and discharge to inpatient rehabilitation decreased, while discharges back to community and to LTC increased.

Conclusions

Although hip fracture rates decreased for older hip fracture patients, the absolute number and prevalence of specific frailty-related characteristics increased. Policy makers should review care models to ensure that adequate resources are provided to the community to offset the expected increase in demand arising from ongoing changes in patients’ characteristics.  相似文献   
32.
Frequentist design for two-arm randomized Phase II clinical trials with outcomes from the exponential dispersion family was proposed previously, where the total sample sizes are minimized under multiple constraints on the standard errors of the estimated group means and their difference. This design was generalized from an approach specific for dichotomous outcomes. The two previous approaches measure the central tendency of each group and treatment effect based on mean and difference in means. Other measures such as median or hazard ratio are more appropriate under certain situations. In addition, the frequentist approaches assume that unknown parameters are fixed values. This does not reflect the reality that uncertainty always exists for unknowns. Compared to the frequentist methods, the Bayesian approach offers a flexible way to measure central tendency and treatment effect, and incorporate uncertainty in parameters of interest into considerations. In this article, we generalize a Bayesian design for Phase II clinical trials with endpoints in the exponential family from the two previously developed frequentist approaches. The proposed design minimizes the total sample sizes under pre-specified constraints on the expected length of posterior credible intervals for measures of treatment effect and central tendency in each group. The design is applicable for trials with fixed or optimal randomization allocation ratio and can be applied under adaptive procedure. Examples of method implementations are provided for different types of endpoints from the exponential family in both fixed and adaptive settings.  相似文献   
33.
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HSS Journal ® - Few studies have quantified clinical improvement following minimally invasive lumbar decompression based on predominant back pain or leg pain. To quantify improvement in...  相似文献   
35.
Background

Adjacent segment disease (ASDz) is a potential complication following lumbar spinal fusion. A common nomenclature based on etiology and ASDz type does not exist and is needed to assist with clinical prognostication, decision making, and management.

Questions/Purposes

The objective of this study was to develop an etiology-based classification system for ASDz following lumbar fusion.

Methods

We conducted a retrospective chart review of 65 consecutive patients who had undergone both a lumbar fusion performed by a single surgeon and a subsequent procedure for ASDz. We established an etiology-based classification system for lumbar ASDz with the following six categories: “degenerative” (degenerative disc disease or spondylosis), “neurologic” (disc herniation, stenosis), “instability” (spondylolisthesis, rotatory subluxation), “deformity” (scoliosis, kyphosis), “complex” (fracture, infection), or “combined.” Based on this scheme, we determined the rate of ASDz in each etiologic category.

Results

Of the 65 patients, 27 (41.5%) underwent surgery for neurogenic claudication or radiculopathy for adjacent-level stenosis or disc herniation and were classified as “neurologic.” Ten patients (15.4%) had progressive degenerative disc pathology at the adjacent level and were classified as “degenerative.” Ten patients (15.4%) had spondylolisthesis or instability and were classified as “instability,” and three patients (4.6%) required revision surgery for adjacent-level kyphosis or scoliosis and were classified as “deformity.” Fifteen patients (23.1%) had multiple diagnoses that included a combination of categories and were classified as “combined.”

Conclusion

This is the first study to propose an etiology-based classification scheme of ASDz following lumbar spine fusion. This simple classification system may allow for the grouping and standardization of patients with similar pathologies and thus for more specific pre-operative diagnoses, personalized treatments, and improved outcome analyses.

  相似文献   
36.
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39.

Introduction

Surgery is evolving, and new techniques are introduced to improve “recovery.” Postoperative recovery is complex, and evaluating the effectiveness of surgical innovations requires assessment of patient-reported outcomes. The Short-Form-36 (SF-36), a generic health-related quality of life questionnaire, is the most commonly used instrument in this context. The objective of this study was to contribute evidence for the validity of the SF-36 as a metric of postoperative recovery.

Methods

Data from 128 patients undergoing planned colorectal surgery at one university hospital between 2005 and 2010 were analyzed. In the absence of a gold standard, the responsiveness and construct validity (known groups and convergent) of the SF-36 were evaluated. Standardized response means were computed for the former and non-parametric tests were used to assess the statistical significance of the changes observed. Multiple linear regression was used to determine whether the SF-36 discriminates between patients with versus without complications and between laparoscopic and open surgery (known groups); correlations between the SF-36 and the 6-min walk test, a measure of functional walking capacity (convergent) was investigated with Spearman’s rank correlation.

Results

The SF-36 was sensitive to clinically important changes. Scores on six of eight domains and the physical component summary score deteriorated postoperatively (SRM 0.86 for the PCS, p < 0.01) and improved to baseline thereafter. Patients with complications had significantly lower scores on five SF-36 domains (with differences from ?9 (?18, ?1), p = 0.04 to ?18 (?32, ?2), p = 0.03), and scores on all subscales were lower than those in a healthy population (p < 0.01 to p = 0.04). The SF-36 did not differentiate between laparoscopic and open surgery. Physical functioning scores correlated with 6MWT distance at 1 and 2 months (Spearman’s r = 0.31 and 0.36, p < 0.01).

Conclusions

The SF-36 is responsive to expected physiological changes in the postoperative period, demonstrates construct validity, and thus constitutes a valid measure of postoperative recovery after planned colorectal surgery. The SF-36 did not, however, discriminate between recovery after laparoscopic and open surgery.  相似文献   
40.

Purpose

In multiple sclerosis (MS), the use of preference-based measures is limited to generic measures such as Health Utilities Index Mark 2 and 3, the EQ-5D and the SF-6D. However, the challenge of using such generic preference-based measures in people with MS is that they may not capture all domains of health relevant to the disease. Therefore, the main aim of this paper is to describe the development of a health state classification system for MS patients. The specific objectives are: (1) to identify items best reflecting the domains of quality of life important to people with MS and (2) to provide evidence for the discriminative capacity of the response options by cross-walking onto a visual analog scale of health rating.

Methods

The data come from an epidemiologically sampled population of people with MS diagnosed post-1994. The dataset consisted of 206 items relating to impairments, activity limitations, participation restrictions, health perception and quality of life. Important domains were identified from the responses to the Patient Generated Index, an individualized measure of quality of life. The extent to which the items formed a uni-dimensional, linear construct was estimated using Rasch analysis, and the best item was selected using the threshold map.

Results

The sample was young (mean age 43) and predominantly female (n = 140/189; 74 %). The P-PBMSI classification system consisted of five items, with three response levels per item, producing a total of 243 possible health states. Regression coefficient values consistently decreased between response levels and the linear test for trend were statistically significant for all items. The linear test for trend indicated that for each item the response options provided the same discriminative ability within the magnitude of their capacity. A scoring algorithm was estimated using a simple additive formula. The classification system demonstrated convergent validity against other measures of similar constructs and known-groups validity between different clinical subgroups.

Conclusion

This study produced a health state classifier system based on items impacted upon by MS, and demonstrated the potential to discriminate the health impact of the disease.  相似文献   
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