Absence of Falciform Ligament Found During Laparoscopic Surgery: A Case Report.

Anatomic variants of hepatic ligaments are rare, and complications attributable to these variants may be difficult to diagnose. Our aim is to contribute to the literature surrounding the incidental finding of a congenital absence of the falciform ligament. We report the case of a 37-year-old man who underwent a laparoscopic cholecystectomy for acute cholecystitis. During the operation, the patient was noted to have an apparent absence of the falciform ligament attachment to the liver. The round ligament was attached from the liver to the anterior abdominal wall at the level of the umbilicus. The round ligament is inserted into the inferior surface of the liver as a thick, cordlike structure encased in fat. In rare cases, the small intestine can pass through a falciform ligament defect and become trapped while remaining within the peritoneal cavity, leading to difficult-to-diagnose internal hernias. This condition can lead to intestinal obstruction, incarceration, and strangulation. This directed our decision to divide the remaining round ligament at the liver and close to the abdominal wall. When defects of hepatic ligaments are found incidentally during laparoscopic surgery, these investigators recommend that the operating surgeon consider dividing the remaining ligament as a protective procedure to prevent complications such as internal hernias, intestinal obstruction, incarceration, and strangulation.

Aging, Race, and Health Disparities: Recommendations From the Research Centers Collaborative Network.

Racial disparities in adverse health outcomes with aging have been well described. Yet, much of the research focuses on racial comparisons, with relatively less attention to the identification of underlying mechanisms. To address these gaps, the Research Centers Collaborative Network held a workshop on aging, race, and health disparities to identify research priorities and inform the investigation, implementation, and dissemination of strategies to mitigate disparities in healthy aging. This article provides a summary of the key recommendations and highlights the need for research that builds a strong evidence base with both clinical and policy implications. Successful execution of these recommendations will require a concerted effort to increase participation of underrepresented groups in research through community engagement and partnerships. In addition, resources to support and promote the training and development of health disparities researchers will be critical in making health equity a shared responsibility for all major stakeholders.

Cash critical care time prices vary substantially by region and hospital ownership: A cross-sectional study.

OBJECTIVES: Emergency department (ED) patients may be billed for critical care time (current procedural terminology codes 99291 and 99292) if they receive at least 30 min of critical care services. We sought to determine the median cash (self-pay) prices for critical care time performed in the ED in the United States and assess for associations between hospital characteristics and prices. METHODS: We performed a cross-sectional analysis of hospital cash prices for critical care time performed in the ED using the first 25 alphabetical states. For each hospital, we recorded hospital characteristics including state, control (nonprofit, governmental, or for-profit), size, teaching status, and system. We then searched for each hospital's cash prices for 99291 and 99292 using Turquoise and hospital websites. We determined the median price for 99291 nationally, regionally, and for large hospital systems. We performed multivariable quantile regression to assess for associations between hospital characteristics and prices for 99291. RESULTS: Of the 2629 eligible hospitals, 2245 (85.4%) and 1893 (72.0%) reported cash prices for 99291 and 99292, respectively. For 99291, the cash price ranged from $45 to $84,775 with a median of $1816 (IQR: $1039-3237). For 99292, the median price was $567 (IQR: $298-1008). On multivariable analysis, hospitals had higher cash prices for 99291 if they were located in the West, for-profit, or part of a large system. In particular, hospitals owned by Tenet Healthcare charged the most for 99291 (median $28,244). CONCLUSION: The cash prices for critical care time vary substantially based on hospital characteristics. In particular, for-profit hospitals and those in the West tend to charge the most. Given that patients who require critical care are unlikely to be able to choose the hospital to which they present, standardization of critical care time fees should be considered.

Age-related social selectivity: An adaptive lens on a later life social phenotype.

Age-related social selectivity is a process in which older humans reduce their number of social partners to a subset of positive and emotionally fulfilling relationships. Although selectivity has been attributed to humans' unique perceptions of time horizons, recent evidence demonstrates that these social patterns and processes occur in other non-human primates, suggesting an evolutionarily wider phenomenon. Here, we develop the hypothesis that selective social behavior is an adaptive strategy that allows social animals to balance the costs and benefits of navigating social environments in the face of age-related functional declines. We first aim to distinguish social selectivity from the non-adaptive social consequences of aging. We then outline multiple mechanisms by which social selectivity in old age may enhance fitness and healthspan. Our goal is to lay out a research agenda to identify selective strategies and their potential benefits. Given the importance of social support for health across primates, understanding why aging individuals lose social connections and how they can remain resilient has vital applications to public health research.

Nitrated Polycyclic Aromatic Hydrocarbon (Nitro-PAH) Signatures and Somatic Mutations in Diesel Exhaust-Exposed Bladder Tumors.

BACKGROUND: Diesel exhaust is a complex mixture, including polycyclic aromatic hydrocarbons (PAH) and nitrated PAHs (nitro-PAH), many of which are potent mutagens and possible bladder carcinogens. To explore the association between diesel exposure and bladder carcinogenesis, we examined the relationship between exposure and somatic mutations and mutational signatures in bladder tumors. METHODS: Targeted sequencing was conducted in bladder tumors from the New England Bladder Cancer Study. Using data on 797 cases and 1,418 controls, two-stage polytomous logistic regression was used to evaluate etiologic heterogeneity between bladder cancer subtypes and quantitative, lifetime estimates of respirable elemental carbon (REC), a surrogate for diesel exposure. Poisson regression was used to evaluate associations between REC and mutational signatures. RESULTS: We observed significant heterogeneity in the diesel-bladder cancer risk relationship, with a strong positive association among cases with high-grade, nonmuscle invasive TP53-mutated tumors compared with controls [ORTop Tertile vs.Unexposed, 4.8; 95% confidence interval (CI), 2.2-10.5; Ptrend < 0.001; Pheterogeneity = 0.002]. In muscle-invasive tumors, we observed a positive association between diesel exposure and the nitro-PAH signatures of 1,6-dintropyrene (RR, 1.93; 95% CI, 1.28-2.92) and 3-nitrobenzoic acid (RR, 1.97; 95% CI, 1.33-2.92). CONCLUSIONS: The relationship between diesel exhaust and bladder cancer was heterogeneous based on the presence of TP53 mutations in tumors, further supporting the link between PAH exposure and TP53 mutations in carcinogenesis. Future studies that can identify nitro-PAH signatures in exposed tumors are warranted to add human data supporting the link between diesel and bladder cancer. IMPACT: This study provides additional insight into the etiology and possible mechanisms related to diesel exhaust-induced bladder cancer.

Weak, but not strong, ties support coalition formation among wild female chimpanzees.

In social species, individuals may be able to overcome competitive constraints on cooperation by leveraging relationships with familiar, tolerant partners. While strong social ties have been linked to cooperation in several social mammals, it is unclear the extent to which weak social ties can support cooperation, particularly among non-kin. We tested the hypothesis that weakly affiliative social relationships support cooperative coalition formation using 10 years of behavioural data on wild female chimpanzees. Female chimpanzees typically disperse and reside with non-kin as adults. Their social relationships are differentiated but often relatively weak, with few dyads sharing strong bonds. Females occasionally form aggressive coalitions together. Three measures of relationship quality-party association, five-metre proximity and whether a dyad groomed-positively predicted coalitions, indicating that relationship quality influenced coalition partnerships. However, dyads that groomed frequently did not form more coalitions than dyads that groomed occasionally, and kin did not cooperate more than expected given their relationship quality. Thus, strong bonds and kinship did not bolster cooperation. We conclude that cooperative coalitions among female chimpanzees depend on social tolerance but do not require strong bonds. Our findings highlight social tolerance as a distinct pathway through which females can cultivate cooperative relationships. This article is part of the theme issue 'Cooperation among women: evolutionary and cross-cultural perspectives'.

Chronic Community Exposure to Environmental Metal Mixtures Is Associated with Selected Cytokines in the Navajo Birth Cohort Study (NBCS).

Many tribal populations are characterized by health disparities, including higher rates of infection, metabolic syndrome, and cancer-all of which are mediated by the immune system. Members of the Navajo Nation have suffered chronic low-level exposure to metal mixtures from uranium mine wastes for decades. We suspect that such metal and metalloid exposures lead to adverse health effects via their modulation of immune system function. We examined the relationships between nine key metal and metalloid exposures (in blood and urine) with 11 circulating biomarkers (cytokines and CRP in serum) in 231 pregnant Navajo women participating in the Navajo Birth Cohort Study. Biomonitored levels of uranium and arsenic species were considerably higher in participants than NHANES averages. Each biomarker was associated with a unique set of exposures, and arsenic species were generally immunosuppressive (decreased cellular and humoral stimulating cytokines). Overall, our results suggest that environmental metal and metalloid exposures modulate immune status in pregnant Navajo women, which may impact long-term health outcomes in mothers and their children.

Healthcare utilization in cancer survivors: six-month longitudinal cohort data.

PURPOSE: To describe healthcare utilization and reasons for delaying medical care and to identify factors that influence high healthcare utilization and care delay among cancer survivors. METHODS: Baseline (n = 991) and 6 month follow-up data (n = 777) were collected among breast, prostate, and colorectal cancer survivors from 32 US cancer centers. Participants completed surveys on healthcare utilization (e.g., number of visits to specific providers) and delay of medical care. We categorized participants as high or low users based on median number of visits. We used logistic regression models to examine factors that predicted high healthcare utilization or delay. RESULTS: Survivors reported a median of 10.5 visits to healthcare providers and 28% reported ever delaying medical care over 6 months. Compared to prostate cancer survivors, breast and colorectal survivors were 2.4 times more likely (CI = 1.2-4.8) and 4 times more likely (CI = 2.2-7.3) to be high healthcare users, respectively. A higher quality of life score predicted high healthcare utilization (OR = 2.4, CI = 2.0-2.8) and delay of medical care (OR = 1.8, CI = 1.5-2.2). Black survivors were 1.5 times more likely than White survivors to be high healthcare users (CI = 1.1-2.0) and respondents reporting a race category other than White or Black were 1.8 times more likely to delay care (CI = 1.3-2.5). Lower levels of self-efficacy predicted greater healthcare use (OR = 0.7, CI = 0.6-0.8) and delay (OR = 0.6, CI = 0.5-0.7). CONCLUSION: Our findings suggest that race, education, marital status, cancer type, time since diagnosis, quality of life, and self-efficacy are associated with both high healthcare utilization and delay among cancer survivors.

Long-Range GABAergic Projections of Cortical Origin in Brain Function.

The study of long-range GABAergic projections has traditionally been focused on those with subcortical origin. In the last few years, cortical GABAergic neurons have been shown to not only mediate local inhibition, but also extend long-range axons to remote cortical and subcortical areas. In this review, we delineate the different types of long-range GABAergic neurons (LRGNs) that have been reported to arise from the hippocampus and neocortex, paying attention to the anatomical and functional circuits they form to understand their role in behavior. Although cortical LRGNs are similar to their interneuron and subcortical counterparts, they comprise distinct populations that show specific patterns of cortico-cortical and cortico-fugal connectivity. Functionally, cortical LRGNs likely induce timed disinhibition in target regions to synchronize network activity. Thus, LRGNs are emerging as a new element of cortical output, acting in concert with long-range excitatory projections to shape brain function in health and disease.

Relación docente-estudiante y compromiso escolar: percepción de estudiantes secundarios con necesidades educativas especiales / Teacher-student relationship and student engagement: perceptions of secondary students with special educational needs / Relação professor-aluno e compromisso escolar: percepção de jovens com necessidades educacionais especiais

Resumen (analítico) Investigaciones previas sostienen que la relación docente-estudiante es un factor relevante para el compromiso escolar y rendimiento académico. Sin embargo, su impacto ha sido poco explorado en estudiantes con necesidades educativas especiales. Este estudio examina la influencia de la relación docente-estudiante en el compromiso escolar según la percepción de estudiantes de primer año medio con necesidades educativas especiales de una Región de Chile. Se realizó un estudio cualitativo, de tipo fenomenológico y de alcance descriptivo-analítico. Se desarrollaron diez entrevistas en profundidad a estudiantes con necesidades educativas especiales, las que se analizaron mediante el método de comparación constante de la teoría fundamentada. Los resultados revelan el rol clave de los/as docentes en el compromiso escolar a través de la satisfacción de las necesidades de vinculación y competencia de sus estudiantes, pero no de su autonomía.

Abstract (analytical) The results of existing research studies show that the teacher-student relationship is a relevant factor that affects academic engagement and school performance. However, there is limited evidence of its impact on students with special educational needs. This study examines the influence of the teacher-student relationship on school engagement based on the perceptions of students with special educational needs in their first year of high school education in Chile. The study used a qualitative, phenomenological, and descriptive-analytical design. A total of ten indepth interviews were conducted with students with special educational needs. The data was analysed using the methodological guidelines of grounded theory. The results highlight the key role of teachers in academic engagement by satisfying students' psychological needs in the areas of connection and competence, but not satisfying students' need for autonomy.

Resumo (analítico) Pesquisas anteriores afirmam que a relação professor-aluno é um fator relevante para o engajamento e desempenho acadêmico. No entanto, seu impacto tem sido pouco explorado em alunos com necessidades educacionais especiais. Este estudo examina a influência da relação professor-aluno no compromisso escolar segundo a percepção dos alunos com alunos com necessidades educacionais especiais do primeiro ano do ensino médio, da Chile. O desenho foi qualitativo, fenomenológico, descritivo-analítico em escopo. Foram realizadas 10 entrevistas em profundidade com alunos com necessidades educacionais especiais. Os dados foram analisados segundo as diretrizes metodológicas da teoria fundamentada nos dados. Os resultados apontam para o papel fundamental do professor no comprometimento escolar, por meio da satisfação das necessidades de vinculação e competência de seus alunos, mas não de sua autonomia.

Contact Ion Pair Formation Is Not Necessarily Stronger than Solvent Shared Ion Pairing.

Vibrational sum frequency spectroscopy (VSFS) and pressure-area Langmuir trough measurements were used to investigate the binding of alkali metal cations to eicosyl sulfate (ESO4) surfactants in monolayers at the air/water interface. The number density of sulfate groups could be tuned by mixing the anionic surfactant with eicosanol. The equilibrium dissociation constant for K+ to the fatty sulfate interface showed 10 times greater affinity than for Li+ and approximately 3 times greater than for Na+. All three cations formed solvent shared ion pairs when the mole fraction of ESO4 was 0.33 or lower. Above this threshold charge density, Li+ formed contact ion pairs with the sulfate headgroups, presumably via bridging structures. By contrast, K+ only bound to the sulfate moieties in solvent shared ion pairing configurations. The behavior for Na+ was intermediate. These results demonstrate that there is not necessarily a correlation between contact ion pair formation and stronger binding affinity.

Overcoming racism in the twin spheres of conservation science and practice.

It is time to acknowledge and overcome conservation's deep-seated systemic racism, which has historically marginalized Black, Indigenous and people of colour (BIPOC) communities and continues to do so. We describe how the mutually reinforcing 'twin spheres' of conservation science and conservation practice perpetuate this systemic racism. We trace how institutional structures in conservation science (e.g. degree programmes, support and advancement opportunities, course syllabuses) can systematically produce conservation graduates with partial and problematic conceptions of conservation's history and contemporary purposes. Many of these graduates go on to work in conservation practice, reproducing conservation's colonial history by contributing to programmes based on outmoded conservation models that disproportionately harm rural BIPOC communities and further restrict access and inclusion for BIPOC conservationists. We provide practical, actionable proposals for breaking vicious cycles of racism in the system of conservation we have with virtuous cycles of inclusion, equality, equity and participation in the system of conservation we want.

Age-related change in adult chimpanzee social network integration.

BACKGROUND: Social isolation is a key risk factor for the onset and progression of age-related disease and mortality in humans. Nevertheless, older people commonly have narrowing social networks, with influences from both cultural factors and the constraints of senescence. We evaluate evolutionarily grounded models by studying social aging in wild chimpanzees, a system where such influences are more easily separated than in humans, and where individuals are long-lived and decline physically with age. METHODOLOGY: We applied social network analysis to examine age-related changes in social integration in a 7+ year mixed-longitudinal dataset on 38 wild adult chimpanzees (22 females, 16 males). Metrics of social integration included social attractivity and overt effort (directed degree and strength), social roles (betweenness and local transitivity) and embeddedness (eigenvector centrality) in grooming networks. RESULTS: Both sexes reduced the strength of direct ties with age (males in-strength, females out-strength). However, males increased embeddedness with age, alongside cliquishness. These changes were independent of age-related changes in social and reproductive status. Both sexes maintained highly repeatable inter-individual differences in integration, particularly in mixed-sex networks. CONCLUSIONS AND IMPLICATIONS: As in humans, chimpanzees appear to experience senescence-related declines in social engagement. However, male social embeddedness and overall sex differences were patterned more similarly to humans in non-industrialized versus industrialized societies. Such comparisons suggest common evolutionary roots to ape social aging and that social isolation in older humans may hinge on novel cultural factors of many industrialized societies. Lastly, individual and sex differences are potentially important mediators of successful social aging in chimpanzees, as in humans. Lay summary: Few biological models explain why humans so commonly have narrowing social networks with age, despite the risk factor of social isolation that small networks pose. We use wild chimpanzees as a comparative system to evaluate models grounded in an evolutionary perspective, using social network analysis to examine changes in integration with age. Like humans in industrialized populations, chimpanzees had lower direct engagement with social partners as they aged. However, sex differences in integration and older males' central positions within the community network were more like patterns of sociality in several non-industrialized human populations. Our results suggest common evolutionary roots to human and chimpanzee social aging, and that the risk of social isolation with age in industrialized populations stems from novel cultural factors.

Urinary markers of oxidative stress respond to infection and late-life in wild chimpanzees.

Oxidative stress (OS) plays a marked role in aging and results from a variety of stressors, making it a powerful measure of health and a way to examine costs associated with life history investments within and across species. However, few urinary OS markers have been examined under field conditions, particularly in primates, and their utility to non-invasively monitor the costs of acute stressors versus the long-term damage associated with aging is poorly understood. In this study, we examined variation in 5 urinary markers of oxidative damage and protection under 5 validation paradigms for 37 wild, chimpanzees living in the Kibale National Park, Uganda. We used 924 urine samples to examine responses to acute immune challenge (respiratory illness or severe wounding), as well as mixed-longitudinal and intra-individual variation with age. DNA damage (8-OHdG) correlated positively with all other markers of damage (F-isoprostanes, MDA-TBARS, and neopterin) but did not correlate with protection (total antioxidant capacity). Within individuals, all markers of damage responded to at least one if not both types of acute infection. While OS is expected to increase with age, this was not generally true in chimpanzees. However, significant changes in oxidative damage were detected within past-prime individuals and those close to death. Our results indicate that OS can be measured using field-collected urine and integrates short- and long-term aspects of health. They further suggest that more data are needed from long-lived, wild animals to illuminate if common age-related increases in inflammation and OS damage are typical or recently aberrant in humans.

Evaluating the impact of physical frailty during ageing in wild chimpanzees (Pan troglodytes schweinfurthii).

While declining physical performance is an expected consequence of ageing, human clinical research has placed increasing emphasis on physical frailty as a predictor of death and disability in the elderly. We examined non-invasive measures approximating frailty in a richly sampled longitudinal dataset on wild chimpanzees. Using urinary creatinine to assess lean body mass, we found moderate but significant declines in physical condition with age in both sexes. While older chimpanzees spent less of their day in the trees and feeding, they did not alter activity budgets with respect to travel or resting. There was little evidence that declining lean body mass had negative consequences independent of age. Old chimpanzees with poor lean body mass rested more often but did not otherwise differ in activity. Males, but not females, in poor condition were more likely to exhibit respiratory illness. Poor muscle mass was associated acutely with death in males, but it did not predict future mortality in either sex. While there may be some reasons to suspect biological differences in the susceptibility to frailty in chimpanzees versus humans, our data are consistent with recent reports from humans that lean, physically active individuals can successfully combat frailty. This article is part of the theme issue 'Evolution of the primate ageing process'.

A global health capstone: an innovative educational approach in a competency-based curriculum for medical students.

BACKGROUND: Global health educational programs for medical and public health professionals have grown substantially in recent years. The University of Illinois Chicago College of Medicine (UICOM) began a global medicine (GMED) program for selected students in 2012 and has since graduated four classes. As part of the four-year curriculum, students complete a longitudinal global health capstone project. This paper describes the global health capstone project as an innovative educational tool within a competency-based curriculum. METHODS: The authors define and describe the longitudinal global health capstone including specific requirements, student deliverables, and examples of how the global health capstone may be used as part of a larger curriculum to teach the competency domains identified by the Consortium of Universities for Global Health. The authors also reviewed the final capstone projects for 35 graduates to describe characteristics of capstone projects completed. RESULTS: The global health capstone was developed as one educational tool within a broader global health curriculum for medical students. Of the 35 capstones, 26 projects involved original research (74%), and 25 involved international travel (71%). Nine projects led to a conference abstract/presentation (26%) while five led to a publication (14%). Twenty-one projects (60%) had subject matter-focused faculty mentorship. CONCLUSIONS: A longitudinal global health capstone is a feasible tool to teach targeted global health competencies and can provide meaningful opportunities for research and career mentorship. Further refinement of the capstone process is needed to strengthen mentorship, and additional assessment methods are needed.

Pretransplantation Cognitive Dysfunction in Advanced-Age Hematologic Cancers: Predictors and Associated Outcomes.

Patients presenting for treatment of hematologic cancers may be at increased risk for cognitive dysfunction before allogeneic hematopoietic stem cell transplantation (HSCT) due to advanced age, previous chemotherapy treatment, deconditioning, and fatigue. Cognitive dysfunction may affect treatment decision making, ability to recall or follow post-HSCT treatment recommendations and overall survival (OS). A total of 448 patients admitted for HSCT between 2011 and 2014 were administered the Montreal Cognitive Assessment (MoCA) by occupational therapists during admission before transplantation, and 260 were reassessed following transplantation and before discharge. We examined select predictor variables, including age, Karnofsky Performance Status, sex, disease type, psychotropic medications, and select outcome variables, including OS, and nonrelapse mortality (NRM). Before transplantation, 36.4% of patients met criteria for cognitive dysfunction. Age was found to be a significant predictor, along with disease type (myelodysplastic syndrome [MDS], myeloproliferative disorder [MPD]). No significant association was found between cognitive dysfunction and OS or NRM. Longitudinal analysis from pretransplantation to post-transplantation indicated significant decline following HSCT. Notably, one-third of the study cohort showed cognitive dysfunction at hospital discharge. A significant proportion of HSCT candidates present with cognitive dysfunction, with older patients and those diagnosed with MDS and MPD at greatest risk in this cohort. Attention to cognitive dysfunction before transplantation may alert the treatment team to high-risk cases that require increased oversight, inclusion by caregivers, and referral to occupational therapy at discharge. Longitudinal follow-up studies are needed to clarify the specific effect of HSCT on cognitive dysfunction and the impact of cognitive dysfunction on transplantation outcomes.

Distinct gene expression and secondary metabolite profiles in suppressor of prosystemin-mediated responses2 (spr2) tomato mutants having impaired mycorrhizal colonization.

Arbuscular mycorrhizal fungi (AMF) colonization, sampled at 32-50 days post-inoculation (dpi), was significantly reduced in suppressor of prosystemin-mediated responses2 (spr2) mutant tomato plants impaired in the ω-3 FATTY ACID DESATURASE7 (FAD7) gene that limits the generation of linolenic acid and, consequently, the wound-responsive jasmonic acid (JA) burst. Contrary to wild-type (WT) plants, JA levels in root and leaves of spr2 mutants remained unchanged in response to AMF colonization, further supporting its regulatory role in the AM symbiosis. Decreased AMF colonization in spr2 plants was also linked to alterations associated with a disrupted FAD7 function, such as enhanced salicylic acid (SA) levels and SA-related defense gene expression and a reduction in fatty acid content in both mycorrhizal spr2 roots and leaves. Transcriptomic data revealed that lower mycorrhizal colonization efficiency in spr2 mutants coincided with the modified expression of key genes controlling gibberellin and ethylene signaling, brassinosteroid, ethylene, apocarotenoid and phenylpropanoid synthesis, and the wound response. Targeted metabolomic analysis, performed at 45 dpi, revealed augmented contents of L-threonic acid and DL-malic acid in colonized spr2 roots which suggested unfavorable conditions for AMF colonization. Additionally, time- and genotype-dependent changes in root steroid glycoalkaloid levels, including tomatine, suggested that these metabolites might positively regulate the AM symbiosis in tomato. Untargeted metabolomic analysis demonstrated that the tomato root metabolomes were distinctly affected by genotype, mycorrhizal colonization and colonization time. In conclusion, reduced AMF colonization efficiency in spr2 mutants is probably caused by multiple and interconnected JA-dependent and independent gene expression and metabolomic alterations.

The impact of current smoking on outcomes after infrainguinal bypass for claudication.

OBJECTIVE: Although smoking cessation is a benchmark of medical management of intermittent claudication, many patients require further revascularization. Currently, revascularization among smokers is a controversial topic, and practice patterns differ institutionally, regionally, and nationally. Patients who smoke at the time of revascularization are thought to have a poor prognosis, but data on this topic are limited. The purpose of this study was to evaluate the impact of smoking on outcomes after infrainguinal bypass for claudication. METHODS: Data from the national Vascular Quality Initiative from 2004 to 2014 were used to identify infrainguinal bypasses performed for claudication. Patients were categorized as former smokers (quit >1 year before intervention) and current smokers (smoking within 1 year of intervention). Demographic and comorbid differences of categorical variables were assessed. Significant predictors were included in adjusted Cox proportional hazards models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) by smoking status for outcomes of major adverse limb event (MALE), amputation-free survival, limb loss, death, and MALE or death. Cumulative incidence curves were created using competing risks modeling. RESULTS: We identified 2913 patients (25% female, 9% black) undergoing incident infrainguinal bypass grafting for claudication. There were 1437 current smokers and 1476 former smokers in our study. Current smoking status was a significant predictor of MALE (HR, 1.27; 95% CI, 1.00-1.60; P = .048) and MALE or death (HR, 1.22; 95% CI, 1.03-1.44; P = .02). Other factors found to be independently associated with poor outcomes in adjusted models included black race, below-knee bypass grafting, use of prosthetic conduit, and dialysis dependence. CONCLUSIONS: Current smokers undergoing an infrainguinal bypass procedure for claudication experienced more MALEs than former smokers did. Future studies with longer term follow-up should address limitations of this study by identifying a data source with long-term follow-up examining the relationship of smoking exposure (pack history and duration) with outcomes.