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Background Sleep-disordered breathing (SDB) has been increasingly recognized as a possible risk factor for adverse perioperative outcomes in non-bariatric surgeries. However, the impact of SDB on postoperative outcomes in patients undergoing bariatric surgery remains less clearly defined. We hypothesized that SDB would be independently associated with worse postoperative outcomes. Methods Data were obtained from the Nationwide Inpatient Sample database, and included a total of 91,028 adult patients undergoing bariatric surgeries from 2004 to 2008. The primary outcomes were in-hospital death, total charges and length of stay. There were two secondary outcomes of interest: respiratory and cardiac complications. Regression models were fitted to assess the independent association between SDB and the outcomes of interest. Results SDB was independently associated with decreased mortality (OR 0.34, 95% CI 0.23-0.50, p<0.001), total charges (-$869, p<0.001), and length of stay (-0.25 days, p<0.001). SDB was independently associated with significantly increased odds ratio of emergent endotracheal intubation (OR 4.35, 95% CI 3.97-4.77, p<0.001), noninvasive ventilation (OR 14.12, 95% CI 12.09-16.51, p<0.001), and atrial fibrillation (OR 1.25, 95% CI 1.11-1.41, p<0.001). Emergent intubation occurred significantly earlier in the postoperative course in patients with SDB. Although non-SDB patients had an overall lower risk of emergent intubation compared to SDB patients, their outcomes were significantly worse when they did get emergently intubated. Conclusions In this large nationally representative sample, despite the increased association of SDB with postoperative cardiopulmonary complications, the diagnosis of SDB was negatively, rather than positively, associated with in-hospital mortality and resource use.

Background Women have disproportionately higher mortality rates relative to incidence for bladder cancer. Multiple etiologies have been proposed, including delayed diagnosis and treatment. Guidelines recommend rule-out of malignancy in men and women presenting with hematuria. We aimed to determine the difference in timing from presentation with hematuria to diagnosis of bladder cancer in women versus men. Methods This is a retrospective population-based study examining the timing from presentation with hematuria to diagnosis of bladder cancer, based on data from the MarketScan databases, which include enrollees of more than 100 health insurances plans of approximately 40 large US employers from 2004 through 2010. All study patients presented with hematuria and were subsequently diagnosed with bladder cancer. The primary outcome measure was number of days between initial presentation with hematuria and diagnosis of bladder cancer by gender. Results 5416 men and 2233 women met inclusion criteria. Mean days from initial hematuria claim to bladder cancer claim was significantly longer in women (85.4 vs. 73.6 days, p<0.001), and the proportion of women with >6 month delays in bladder cancer diagnosis significantly higher (17.3% vs. 14.1%, p<0.001). Women were more likely to be diagnosed with urinary tract infection (OR 2.32 [95% CI 2.07–2.59]) and less likely to undergo abdominal or pelvic imaging (OR 0.80 [95% CI 0.71–0.89]). Conclusions Both men and women experience significant delays between presentation with hematuria and diagnosis of bladder cancer, with longer delays for women. This may be partly responsible for the gender-based discrepancy in outcomes associated with bladder cancer.

The ''3-color, 46-bead'' model of a folding polypeptide is the vehicle for adapting to proteins a mode of analysis used heretofore for atomic clusters, to relate the topography of the potential surface to the dynamics that lead to formation of selected structures. The analysis is based on sequences of stationary points-successive minima, joined by saddles-that rise monotonically in energy from basin bottoms. Like structure-seeking clusters, the potential surface of the model studied here is staircase-like, rather than sawtoothlike, with highly collective motions required for passage from one minimum to the next. The surface has several deep basins whose minima correspond to very similar structures, but which are separated by high energy barriers.A challenge to chemical theory has been finding a way to infer from attainable data at the atomic level why some systems readily form glasses and others fall into very selective structures. It is possible to do this now for atomic clusters by examining sequences of linked stationary points on the potential surface, particularly sequences whose minima rise monotonically from the bottoms of basins on the surface (1-4). The signature of a glass-former seems to be a complex potential with a sawtooth topography-a potential whose successive minima differ little in energy, relative to the heights of the energy barriers that separate them. In contrast, the signature of a ''structure-seeker'' appears to be a complex potential with a staircase topography-a potential some of whose adjacent minima differ considerably in energy, relative to the energy barrier between them. The mechanistic difference between the two, at the atomic level, is that only a very few particles move when a glass-former passes from one local minimum to the next, whereas in a structure-seeker, many particles move in the well-to-well passages, and in some of these, the internal potential energy changes considerably. Examples of glass-formers are such rare-gas clusters as Ar 19 and Ar 55 (2,3,5); an example of a good structure-seeker is (KCl) 32 , which, when quenched (in molecular dynamics simulations) from liquid, finds one of its few hundred rocksalt structures rather than one of its (roughly) 10 13 amorphous structures (6). Only if the cluster is quenched at a rate above 10 13 K͞s-i.e., if the energy is removed during only 5-10 vibrational periods-can this system be trapped in an amorphous structure (6, 7).Even as the results emerged for clusters, it was apparent that the same characteristics might govern the structure-seeking propensities of proteins and other biopolymers. The interatomic forces in proteins differ very much indeed from those between the atoms of clusters, but if the characterization is correct, that difference is irrelevant to the generic issue of why some species are good structure-seekers and others are good glass-formers. The crucial issue is the topography of the potential surface, not the microscopic origin of the forces that give rise to that topography. We therefore undertook...

Sleep-disordered breathing (SDB) is increasingly recognized as a possible risk factor for adverse perioperative outcomes. [1][2][3][4][5][6] Given the important implications of untreated SDB, the American Society of Anesthesiologists recommends screening patients prior to surgery for SDB and implementing treatment if SDB is present. 7 However, despite this growing awareness, there is a paucity of large-scale studies that examined the impact of SDB on postoperative outcomes. Moreover, given that systematic screening would impose a Background: Systematic screening and treatment of sleep-disordered breathing (SDB) or obstructive sleep apnea (OSA) in presurgical patients would impose a signifi cant cost burden; therefore, it is important to understand whether SDB is associated with worse postoperative outcomes. We sought to determine the impact of SDB on postoperative outcomes in patients undergoing four specifi c categories of elective surgery (orthopedic, prostate, abdominal, and cardiovascular). The primary outcomes were in-hospital death, total charges, and length of stay (LOS). Two secondary outcomes of interest were respiratory and cardiac complications. Methods: Data were obtained from the Nationwide Inpatient Sample database. Regression models were fi tted to assess the independent association between SDB and the outcomes of interest. 73; P , .001) but had no impact on mortality in the prostate surgery group. SDB was independently associated with a small, but statistically signifi cant increase in estimated mean LOS by 0.14 days ( P , .001) and estimated mean total charges by $860 ( P , .001) in the orthopedic surgery group but was not associated with increased LOS or total charges in the prostate surgery group. In the abdominal and cardiovascular surgery groups, SDB was associated with a signifi cant decrease in adjusted mean LOS of 1.1 days and 0.35 days, respectively ( P , .001 for both groups), and adjusted mean total charges of $3,814 and $4,592, respectively ( P , .001 for both groups). SDB was independently associated with a signifi cantly increased OR for emergent intubation and mechanical ventilation, noninvasive ventilation, and atrial fi brillation in all four surgical categories. Emergent intubation occurred signifi cantly earlier in the postoperative course in patients with SDB. In the subgroup of patients requiring emergent intubation, LOS, total charges, pneumonias, and in-hospital death were signifi cantly higher in those without SDB. Conclusions: In this large national study, despite the increased independent association of SDB with postoperative cardiopulmonary complications, the diagnosis of SDB was not independently associated with an increased rate of in-hospital death. SDB had a mixed impact on LOS and total charges by surgical category.