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ObjectivesSpinal cord stimulation (SCS) is a surgical treatment modality reserved for a subset of patients with neuropathic pain in which conventional pharmacologic treatment has proven insufficient. Previous studies have suggested a possible negative relationship between opioid use at referral and subsequent success of SCS therapy. The aim of this cohort study was to investigate whether preoperative opioid use was associated with inferior SCS outcomes.Materials and MethodsData were obtained from the Danish Neurizon Neuromodulation Database and comprised preoperative registrations of analgesic use, postoperative Patients’ Global Impression of Change (PGIC) ratings, pre- and postoperative pain intensity scores (Numeric Rating Scale), and detailed surgical data. Patients were dichotomized according to preoperative opioid use (users vs nonusers) with subsequent assessment of the latest PGIC rating, reduction in pain intensity, and current treatment status (implanted/explanted). In addition, daily preoperative opioid dosages were quantified in oral morphine equivalents (OME) and correlated to the treatment outcomes.ResultsA total of 467 patients were included; 296 consumed opioids before SCS implantation (median 80 OME/d). Preoperative opioid use was not associated with the latest PGIC rating, reduction in pain intensity (30% or 50%), or risk of undergoing explantation (median follow-up = 3.0 years). Likewise, preoperative median OME per day of opioid users was not correlated with any of the defined outcomes.ConclusionsPreoperative opioid usage did not predict the outcome of SCS therapy in a large cohort of patients permanently implanted with an SCS system. The results do not support withholding otherwise well-indicated SCS therapy in patients with chronic neuropathic pain conditions based merely on preoperative opioid usage.  相似文献   
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This study aimed to assess clinical, functional, and hemodynamic characteristics of heart‐transplanted (HTX) patients during exercise. We performed comprehensive echocardiographic graft function assessment during invasive hemodynamic semi‐supine exercise test in 57 HTX patients. According to hemodynamics findings, patients were divided into Group A: normal left ventricular (LV) filling pressure (FP): pulmonary capillary wedge pressure (PCWP) <15 mmHg at rest and <25 mmHg at peak exercise, and Group B: elevated LV‐FP: PCWP ≥15 mmHg at rest or ≥25 mmHg at peak exercise. Thirty‐one patients (54%) had normal LV‐FP and 26 patients (46%) had elevated LV‐FP. The latter had higher cumulative rejection burden (P < 0.01) and were more symptomatic (NYHA class >1) (P < 0.05), and cardiac allograft vasculopathy (CAV) was more prevalent (P < 0.05). With exercise, the changes in both left‐ and right‐sided filling pressures were significantly increased, whereas LV longitudinal myocardial deformation was lower (P < 0.05) in patients with elevated LV‐FP than in patients with normal LV‐FP. No between‐group difference was observed for cardiac index or LV ejection fraction (LVEF) during exercise. In conclusion, elevated LV‐FP can be demonstrated in approximately 50% of HTX patients. Patients with elevated LV‐FP have impaired myocardial deformation capacity, higher prevalence of CAV, and higher rejection burden, and were more symptomatic. Exercise test with the assessment of longitudinal myocardial deformation should be considered in routine surveillance of HTX patients as a marker of restrictive filling (ClinicalTrials.gov Identifier: NCT02077764).  相似文献   
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The natural history, microevolution, and patterns of interindividual transmission and global dissemination of the JP2 clone of Aggregatibacter (Actinobacillus) actinomycetemcomitans were studied by population genetic analysis. The JP2 clone is strongly associated with aggressive periodontitis in adolescents of African descent and differs from other clones of the species by several genetic peculiarities, including a 530-bp deletion in the promoter region of the leukotoxin gene operon, which results in increased leukotoxic activity. Multilocus sequence analysis of 82 A. actinomycetemcomitans strains, 66 of which were JP2 clone strains collected over a period of more than 20 years, confirmed that there is a clonal population structure with evolutionary lineages corresponding to serotypes. Although genetically highly conserved, as shown by alignment of sequences of eight housekeeping genes, strains belonging to the JP2 clone had a number of point mutations, particularly in the pseudogenes hbpA and tbpA. Characteristic mutations allowed isolates from individuals from the Mediterranean area and from West Africa, including the Cape Verde Islands, to be distinguished. The patterns of mutations indicate that the JP2 clone initially emerged as a distinct genotype in the Mediterranean part of Africa approximately 2,400 years ago and subsequently spread to West Africa, from which it was transferred to the American continents during the transatlantic slave trade. The sustained exclusive colonization of individuals of African descent despite geographical separation for centuries suggests that the JP2 clone has a distinct host tropism. The colonization of family members by JP2 clone strains with unique point mutations provides strong evidence that there is intrafamilial transmission and suggests that dissemination of the JP2 clone is restricted to close contacts.  相似文献   
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Introduction

In 2009 the Department of Health instructed McKinsey & Company to provide advice on how commissioners might achieve world class National Health Service productivity. Asymptomatic inguinal hernia repair was identified as a potentially cosmetic procedure, with limited clinical benefit. The Birmingham and Solihull primary care trust cluster introduced a policy of watchful waiting for asymptomatic inguinal hernia, which was implemented across the health economy in December 2010. This retrospective cohort study aimed to examine the effect of a change in clinical commissioning policy concerning elective surgical repair of asymptomatic inguinal hernias.

Methods

A total of 1,032 patients undergoing inguinal hernia repair in the 16 months after the policy change were compared with 978 patients in the 16 months before. The main outcome measure was relative proportion of emergency repair in groups before and after the policy change. Multivariate binary logistic regression was used to adjust the main outcome for age, sex and hernia type.

Results

The period after the policy change was associated with 59% higher odds of emergency repair (3.6% vs 5.5%, adjusted odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.03–2.47). In turn, emergency repair was associated with higher odds of adverse events (4.7% vs 18.5%, adjusted OR: 3.68, 95% CI: 2.04–6.63) and mortality (0.1% vs 5.4%, p<0.001, Fisher’s exact test).

Conclusions

Introduction of a watchful waiting policy for asymptomatic inguinal hernias was associated with a significant increase in need for emergency repair, which was in turn associated with an increased risk of adverse events. Current policies may be placing patients at risk.  相似文献   
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