Insights from Application of a Hierarchical Spatio-Temporal Model to an Intensive Urban Black Carbon Monitoring Dataset.

Existing regulatory pollutant monitoring networks rely on a small number of centrally located measurement sites that are purposefully sited away from major emission sources. While informative of general air quality trends regionally, these networks often do not fully capture the local variability of air pollution exposure within a community. Recent technological advancements have reduced the cost of sensors, allowing air quality monitoring campaigns with high spatial resolution. The 100×100 black carbon (BC) monitoring network deployed 100 low-cost BC sensors across the 15 km2 West Oakland, CA community for 100 days in the summer of 2017, producing a nearly continuous site-specific time series of BC concentrations which we aggregated to one-hour averages. Leveraging this dataset, we employed a hierarchical spatio-temporal model to accurately predict local spatio-temporal concentration patterns throughout West Oakland, at locations without monitors (average cross-validated hourly temporal R 2=0.60). Using our model, we identified spatially varying temporal pollution patterns associated with small-scale geographic features and proximity to local sources. In a sub-sampling analysis, we demonstrated that fine scale predictions of nearly comparable accuracy can be obtained with our modeling approach by using ~30% of the 100×100 BC network supplemented by a shorter-term high-density campaign.

Risks of Zolpidem among Patients with Chronic Obstructive Pulmonary Disease.

Rationale: Nonbenzodiazepine benzodiazepine receptor agonists (NBZRA, e.g., zolpidem) are frequently used to treat insomnia among patients with chronic obstructive pulmonary disease (COPD). However, multiple observational studies find that patients with COPD who are prescribed NBZRAs have greater risks for mortality and respiratory complications than patients without such prescriptions. Without an active comparator, these studies are susceptible to confounding by indication. Objectives: Compare the risk of death or inpatient COPD exacerbation among patients receiving zolpidem relative to patients receiving other hypnotics. Methods: Using nationwide Veterans Health Administration (VA) data, we identified patients with clinically diagnosed COPD and new receipt of zolpidem or another hypnotic available on VA formulary without prior authorization (melatonin, trazodone, doxepin). We excluded those receiving traditional benzodiazepines or multiple concurrent hypnotics. We propensity-matched patients receiving zolpidem to other hypnotics on 32 variables, including demographics, comorbidities, and markers of COPD severity. We compared risk of the primary composite outcome of death or inpatient COPD exacerbation over 1 year. In secondary analyses, we propensity-matched patients receiving zolpidem to those without hypnotic receipt. Results: Among 283,740 patients meeting inclusion criteria, 1,126 (0.4%) received zolpidem and 3,057 (1.1%) received other hypnotics. We propensity-matched patients receiving zolpidem 1:1 to peers receiving other hypnotics. We did not find a difference in the primary composite outcome of death or inpatient exacerbation (hazard ratio, 0.97; 95% confidence interval [CI], 0.77-1.23). In secondary analyses comparing patients receiving zolpidem to matched peers without hypnotic receipt, we observed greater risk of death or inpatient exacerbation with zolpidem (hazard ratio, 1.40; 95% CI, 1.09-1.81). Conclusions: Among patients with COPD, we did not observe greater risks after new receipt of zolpidem relative to other hypnotics. However, we did observe greater risks relative to those without hypnotic receipt. This latter finding may reflect: 1) residual, unmeasured confounding related to insomnia; or 2) true adverse effects of hypnotics across classes. Future work is needed to better understand the risks of hypnotics in COPD.

The Impact of Changing Race-Specific Equations for Lung Function Tests among Veterans with COPD.

RATIONALE: The American Thoracic Society recommended a single reference equation for spirometry but the impact to patients is not known. OBJECTIVE: To estimate the effect of changing to a single reference equation among Veterans with chronic obstructive pulmonary disease (COPD). METHODS: Cross-sectional study including Veterans aged ≥40 to ≤89 years with COPD and spirometry results from 21 facilities between 2010 - 2019. We collected race/ethnicity data from the electronic health record. We estimated the percentage change in the number of Veterans with lung function meeting clinical thresholds used to determine eligibility for lung resection for cancer, lung volume reduction surgery (LVRS), and lung transplant referral. We estimated the change for each level of VA service connection and financial impact. RESULTS: We identified 44,892 Veterans; Asian (0.5%), Black (11.8%), White (80.8%), and Hispanic (1.8%). When changing to a single reference equation, Asian and Black Veterans had reduced predicted lung function that could result in less surgical lung resection (4.4% and 11.1% respectively), while increasing LVRS (1.7% and 3.8%), and lung transplant evaluation for Black Veterans (1.2%). White Veterans had increased predicted lung function and could experience increased lung resection (8.1%), with less LVRS (3.3%), and lung transplant evaluation (0.9%). Some Asian and Black Veterans could experience an increase in monthly disability payments (+$540.38 and $398.38), while Hispanic White and White Veterans could see a decrease (-$588.79). When aggregated, Hispanic Veterans experienced changes attributable to their racial identity, and because this sample was predominantly Hispanic White, had similar results to White Veterans. CONCLUSIONS: Changing the reference equation could affect access to treatment and disability benefits, depending on race. If adopted, the use of discrete clinical thresholds needs to be reassessed, considering patient-centered outcomes.

Sleep Testing and Mortality in a Propensity-matched Cohort of Patients with Chronic Obstructive Pulmonary Disease.

Rationale: Many advocate the application of propensity-matching methods to real-world data to answer key questions around obstructive sleep apnea (OSA) management. One such question is whether identifying undiagnosed OSA impacts mortality in high-risk populations, such as those with chronic obstructive pulmonary disease (COPD). Objectives: Assess the association of sleep testing with mortality among patients with COPD and a high likelihood of undiagnosed OSA. Methods: We identified patients with COPD and a high likelihood of undiagnosed OSA. We then distinguished those receiving sleep testing within 90 days of index COPD encounters. We calculated propensity scores for testing based on 37 variables and compared long-term mortality in matched groups. In sensitivity analyses, we compared mortality using inverse propensity weighting and instrumental variable methods. We also compared the incidence of nonfatal events including adverse outcomes (hospitalizations and COPD exacerbations) and routine services that are regularly indicated in COPD (influenza vaccination and pulmonary function testing). We compared the incidence of each nonfatal event as a composite outcome with death and separately compared the marginal probability of each nonfatal event independently, with death as a competing risk. Results: Among 135,958 patients, 1,957 (1.4%) received sleep testing. We propensity matched all patients with sleep testing to an equal number without testing, achieving excellent balance on observed confounders, with standardized differences < 0.10. We observed lower mortality risk among patients with sleep testing (incidence rate ratio, 0.88; 95% confidence interval [CI], 0.79-0.99) and similar results using inverse propensity weighting and instrumental variable methods. Contrary to mortality, we found that sleep testing was associated with a similar or greater risk for nonfatal adverse events, including inpatient COPD exacerbations (subhazard ratio, 1.29; 95% CI, 1.02-1.62) and routine services like influenza vaccination (subhazard ratio, 1.26; 95% CI, 1.17-1.36). Conclusions: Our disparate findings can be interpreted in multiple ways. Sleep testing may indeed cause both reduced mortality and greater incidence of nonfatal adverse outcomes and routine services. However, it is also possible that our findings stem from residual confounding by patients' likelihood of accessing care. Given the limitations of propensity-based analyses, we cannot confidently distinguish these two possibilities. This uncertainty highlights the limitations of using propensity-based analyses to guide patient care and policy decisions.

Protocol for a pragmatic trial testing a self-directed lifestyle program targeting weight loss among patients with obstructive sleep apnea (POWER Trial).

BACKGROUND: Obesity comprises the single greatest reversible risk factor for obstructive sleep apnea (OSA). Despite the potential of lifestyle-based weight loss services to improve OSA severity and symptoms, these programs have limited reach. POWER is a pragmatic trial of a remote self-directed weight loss care among patients with OSA. METHODS: POWER randomizes 696 patients with obesity (BMI 30-45 kg/m2) and recent diagnosis or re-confirmation of OSA 1:1 to either a self-directed weight loss intervention or usual care. POWER tests whether such an intervention improves co-primary outcomes of weight and sleep-related quality of life at 12 months. Secondary outcomes include sleep symptoms, global ratings of change, and cardiovascular risk scores. Finally, consistent with a hybrid type 1 approach, the trial embeds an implementation process evaluation. We will use quantitative and qualitative methods including budget impact analyses and qualitative interviews to assess barriers to implementation. CONCLUSIONS: The results of POWER will inform population health approaches to the delivery of weight loss care. A remote self-directed program has the potential to be disseminated widely with limited health system resources and likely low-cost.

Lifestyle Intervention and Excess Weight in Chronic Obstructive Pulmonary Disease (COPD): INSIGHT COPD Randomized Clinical Trial.

Rationale: Being overweight or obese is common among patients with chronic obstructive pulmonary disease (COPD), but whether interventions targeted at weight loss improve functional impairments is unknown. Objectives: INSIGHT (Intervention Study in Overweight Patients with COPD) tested whether a pragmatic low-intensity lifestyle intervention would lead to better physical functional status among overweight or obese participants with COPD. Methods: The trial was a 12-month, multicenter, patient-level pragmatic clinical trial. Participants were recruited from April 2017 to August 2019 from 38 sites across the United States and randomized to receive usual care or usual care plus lifestyle intervention. The intervention was a self-directed video program delivering the Diabetes Prevention Program's Group Lifestyle Balance curriculum. Results: The primary outcome was 6-minute-walk test distance at 12 months. Priority secondary outcomes were postwalk modified Borg dyspnea at 12 months and weight at 12 months. Participants (N = 684; mean age, 67.0 ± 8.0 yr [standard deviation]; 41.2% female) on average were obese (body mass index, 33.0 ± 4.6 kg/m2) with moderate COPD (forced expiratory volume in 1 second % predicted, 58.1 ± 15.7%). At 12 months, participants randomized to the intervention arm walked farther (adjusted difference, 42.3 ft [95% confidence interval (CI), 7.9-76.7 ft]; P = 0.02), had less dyspnea at the end of the 6-minute-walk test (adjusted difference, -0.36 [95% CI, -0.63 to -0.09]; P = 0.008), and had greater weight loss (adjusted difference, -1.34 kg [95% CI, -2.33 to -0.34 kg]; P = 0.008) than control participants. The intervention did not improve the odds of achieving clinically meaningful thresholds of walk distance (98.4 ft) or dyspnea (1 unit) but did achieve meaningful thresholds of weight loss (3% and 5%). Conclusions: Among participants with COPD who were overweight or obese, a self-guided low-intensity video-based lifestyle intervention led to modest weight loss but did not lead to clinically important improvements in physical functional status and dyspnea. Clinical trial registered with www.clinicaltrials.gov (NCT02634268).

The lung allocation score and other available models lack predictive accuracy for post-lung transplant survival.

BACKGROUND: Improved predictive models are needed in lung transplantation in the setting of a proposed allocation system that incorporates longer-term post-transplant survival in the United States. Allocation systems require accurate mortality predictions to justly allocate organs. METHODS: Utilizing the United Network for Organ Sharing database (2005-2017), we fit models to predict 1-year mortality based on the Lung Allocation Score (LAS), the Chan, et al, 2019 model, a novel "clinician" model (a priori clinician selection of pre-transplant covariates), and two machine learning models (Least Absolute Shrinkage and Selection Operator; LASSO and Random Forests) for predicting 1-year and 3-year post-transplant mortality. We compared predictive accuracy among models. We evaluated the calibration of models by comparing average predicted probability vs observed outcome per decile. We repeated analyses fit for 3-year mortality, disease category, including donor covariates, and LAS era. RESULTS: The area under the cure for all models was low, ranging from 0.55 to 0.62. All exhibited reasonable negative predictive values (0.87-0.90), but the positive predictive value for was poor (all <0.25). Evaluating LAS calibration found 1-year post-transplant estimates consistently overestimated risk of mortality, with greater differences in higher deciles. LASSO, Random Forests, and clinician models showed no improvement when evaluated by disease category or with the addition of donor covariates and performed worse for 3-year outcomes. CONCLUSIONS: The LAS overestimated patients' risk of post-transplant death, thus underestimating transplant benefit in the sickest candidates. Novel models based on pre-transplant recipient covariates failed to improve prediction. There should be wariness in post-transplant survival predictions from available models.

Low body mass index as a barrier to lung transplant in cystic fibrosis.

RATIONALE: Low body mass index (BMI) may influence lung transplant decisions for patients with advanced cystic fibrosis (CF) lung disease. OBJECTIVE: Determine whether patients with advanced CF lung disease and BMI ≤17 kg/m2 are less likely to be listed for lung transplant or have a higher risk of death without listing compared to those with higher BMI. METHODS: Using merged United Network for Organ Sharing and CF Foundation Patient Registries, we identified adults with onset of advanced lung disease (FEV1 ≤ 40% predicted) between May-2005 and December-2016. We analyzed survival using competing risks regression with cause-specific risks of listing for lung transplant and death without listing. BMI ≤ 17 kg/m2 was our predictor. MEASUREMENTS AND MAIN RESULTS: Among 5,121 CF patients with advanced lung disease, 23% were listed for lung transplant (n = 1,201), 23% died without listing (n = 1,190), and 44% were alive without listing (n = 2,730) as of December-2016. Patients with BMI ≤ 17 kg/m2 were less likely to be listed for transplant (HR 0.69; 95% CI 0.57, 0.83) and more likely to die without listing (HR 1.63; 95% CI 1.41, 1.88). We identified important regional variations in the likelihood of referral and listing, based on BMI. CONCLUSIONS: Patients with advanced CF lung disease and BMI ≤ 17 kg/m2 are less likely to be listed for lung transplant and have a higher risk of dying without listing, compared to those with higher BMI. Regional differences suggest access to transplant for malnourished CF patients may be limited by location.

Development and Internal Validation of a Prognostic Model of the Probability of Death or Lung Transplantation Within 2 Years for Patients With Cystic Fibrosis and FEV1 ≤ 50% Predicted.

BACKGROUND: Improved methods are needed to risk-stratify patients with cystic fibrosis (CF) and reduced FEV1. RESEARCH QUESTIONS: What are the predictors of death or lung transplantation (LTx) within 2 years among patients with CF whose FEV1 ≤ 50% predicted? Do these markers similarly predict outcomes among G551D patients taking ivacaftor since 2012? STUDY DESIGN AND METHODS: Patients with CF, age ≥ 6 years with FEV1 ≤ 50% predicted as of December 31, 2014, were identified in a data set that merged Cystic Fibrosis Foundation and United Network for Organ Sharing (UNOS) registries. The least absolute shrinkage and selection operator (LASSO) method was applied to a randomly selected training set to select important prognostic variables. Accuracy and association of the model with death or LTx with 2 years (2-year death or LTx) were validated via logistic regression on an independent test set. Sensitivity analyses explored predictors for patients with UNOS data. RESULTS: FEV1 percent predicted (OR, 1.51 for 5% decrease; 95% CI, 1.27-1.81), number of pulmonary exacerbations treated with IV antibiotics (OR, 1.35; 95% CI, 1.11-1.65), and continuous or nocturnal oxygen (OR, 3.71; 95% CI, 1.81-7.59) were significantly associated with 2-year death or LTx. Our model predicted outcomes with greater sensitivity (ratio of sensitivity, 1.26; 95% CI, 1.02-1.54), ratio of positive predictive value (1.25; 95% CI, 1.05-1.51), and ratio of negative predictive value (1.04; 95% CI, 1.01-1.07) than FEV1 < 30% predicted. Among those taking ivacaftor in 2014, only FEV1 remained associated with 2-year death or LTx. For patients with UNOS data, LASSO identified additional covariates of interest, including noninvasive ventilation use, low hemoglobin, pulmonary arterial systolic pressure, supplemental oxygen, mechanical ventilation, FEV1 percent predicted, and cardiac index. INTERPRETATION: Among individuals with CF and FEV1 ≤ 50% predicted, FEV1 percent predicted, oxygen therapy, and number of pulmonary exacerbations predicted 2-year death or LTx. Although limited by small sample size, only FEV1 remained predictive in patients receiving highly effective modulator therapy. Additional physiologic variables could improve prognostication in CF.

Use of elexacaftor/tezacaftor/ivacaftor among cystic fibrosis lung transplant recipients.

BACKGROUND: Cystic fibrosis (CF) lung transplant (LT) recipients may warrant treatment with elexacaftor/tezacaftor/ivacaftor (ETI) to improve extrapulmonary manifestations of CF. Our objectives were to identify reasons for prescribing ETI after LT and evaluate changes in body mass index (BMI), hemoglobin A1c, hemoglobin, and liver enzymes. METHODS: This was an electronic health record-based cohort study, October 2019-September 2020, at 14 CF LT Consortium sites in North America. The study included CF LT recipients prescribed ETI after transplant. Differences in BMI, A1c, and hemoglobin were assessed with paired t-tests. RESULTS: There were 94 patients prescribed ETI; indications included sinus disease (68%), GI symptoms (39%), or low BMI (19%). Prescriptions were written by CF physicians (34%), LT physicians (27%), or physicians who practice both CF and LT (39%). Forty patients (42%) stopped ETI at a median of 56 days [IQR 26, 139] after start/prescription date. ETI was not associated with a significant change in BMI (0.2 kg/m2, 95% CI [-0.1, 0.6], p = 0.150), but was associated with decreased A1c (0.4%, 95% CI 0.2, 0.7, p = 0.003), and increased hemoglobin for patients with anemia (0.6 g/dL, 95% CI 0.2, 1.0, p = 0.007). Three people (3%) stopped ETI due to elevated transaminases. CONCLUSIONS: ETI is rarely prescribed for non-pulmonary indications after LT for CF. Further study is needed to determine the risks and benefits of ETI in the CF lung transplant population given the potential for drug interactions, side effects leading to discontinuation of ETI, and the possible mechanisms for ETI to positively impact long-term post-transplant outcomes.

Hemoptysis and the Risk for Lung Transplant or Death without Transplant in Individuals with Cystic Fibrosis in the United States.

Rationale: Hemoptysis is a common and important complication in persons with cystic fibrosis (PwCF). Despite this, there is limited literature on the impact of hemoptysis on contemporary cystic fibrosis (CF) outcomes. Objectives: Evaluate whether hemoptysis increases the risk of lung transplant or death without a transplant in PwCF. Methods: We reviewed a dataset of PwCF ages 12 years or older from the CFFPR (CF Foundation Patient Registry) that included 29,587 individuals. We identified hemoptysis as our predictor of interest and categorized PwCF as either no hemoptysis, any hemoptysis (submassive and/or massive), or massive hemoptysis. We subsequently evaluated whether hemoptysis, as defined above, was associated with death without transplant or receipt of lung transplant via logistic regression. We adjusted for age, sex, body mass index, forced expiratory volume in one second (FEV1), number of exacerbations, supplemental oxygen use, CF-related diabetes, and Pseudomonas aeruginosa colonization status. Subgroup analyses were performed in advanced lung disease, defined as PwCF with an FEV1 <40% predicted. Results: PwCF with any form of hemoptysis were more likely to progress to lung transplant or die without transplant than PwCF who did not have hemoptysis (odds ratio [OR], 1.3 [95% confidence interval (CI), 1.1-1.7]). The effect size of these associations was larger when hemoptysis events were classified as "massive" (massive hemoptysis OR, 2.2 [95% CI, 1.2-3.8]) or in PwCF with advanced lung disease (massive hemoptysis in advanced lung disease OR, 3.2 [95% CI 1.3-8.2]). Conclusions: Hemoptysis is associated with an increased risk of lung transplant and death without a transplant in PwCF, especially among those with massive hemoptysis or advanced lung disease. Our results suggest that hemoptysis functions as a useful predictor of serious outcomes in PwCF and may be important to incorporate into risk prediction models and/or transplant decisions in CF.

Body Mass Index Recovery after Lung Transplant for Cystic Fibrosis.

Rationale: Many lung transplant recipients with cystic fibrosis (CF) have low preoperative body mass index (BMI); however, post-transplant BMI recovery is not well understood. Objectives: To evaluate BMI recovery (⩾18.5 kg/m2) among CF lung transplant recipients with low preoperative BMI and to investigate the association of survival with BMI recovery. Methods: The United Network for Organ Sharing and CF Foundation patient registries (June 2005-December 2016) were used to identify CF lung transplant recipients. Among recipients surviving ⩾1 year, Cox modeling compared post-transplant 1-year conditional survival between recipients with low (<17 and 17-18.49 kg/m2) versus normal preoperative BMI, stratified by BMI recovery. Results: Of 1,977 CF lung transplant recipients, 272 (14%) and 449 (23%) had a preoperative BMI of <17 and 17-18.49 kg/m2, respectively. For subgroups with a BMI of <17 and 17-18.49 kg/m2, 29% versus 49%, respectively, of those alive at 1 year recovered their BMI. Among recipients with low preoperative BMI, adjusted post-transplant 1-year conditional survival was worse than that in those with preoperative BMI ⩾ 18.5 kg/m2; however, BMI recovery mitigated this. Preoperative BMI < 17 kg/m2 had an adjusted hazard ratio of 1.29 (95% confidence interval [CI], 0.92-1.81) with BMI recovery versus 1.57 (95% CI, 1.09-2.25) without recovery, and preoperative BMI 17-18.49 kg/m2 had an adjusted hazard ratio of 1.28 (95% CI, 1.02-1.61) with BMI recovery versus 1.72 (95% CI, 1.14-2.59) without recovery. Conclusions: Patients with lower preoperative BMI were less likely to achieve BMI recovery within 1 year. However, for those who did, BMI recovery within 1 year after transplant was associated with longer survival.

Validation of the French 3-year prognostic score for death or lung transplant in the United States cystic fibrosis population.

In 2017, Nkam et al. published a prognostic score to predict death or lung transplant within 3 years among adult cystic fibrosis (CF) patients. Their model was developed using French CF registry data and was subsequently validated in the Canadian CF registry. We evaluated this prognostic score using data from adult patients with CF in the United States (US) CF Foundation Patient registry, combined with lung transplant records from the United Network for Organ Sharing (UNOS) Registry (2013 to 2016) (n=11,542). We found that the prognostic score had a very good discriminative index predicting death or lung transplant in the US CF population (AUC 0.88, 95% CI 0.88-0.89) with an odds ratio (OR) of 2.83 (95% CI 2.69 - 2.97) for each unit increase in the score. However, it did not provide significant additional utility over an FEV1 ≤30% of predicted as a predictor of death or lung transplant.

Variability in azithromycin practices among lung transplant providers in the International Society for Heart and Lung Transplantation Community.

Chronic lung allograft dysfunction (CLAD) is the most important long-term complication after lung transplant (LTx), and clinical experience suggests significant variability in its management. We sought to capture azithromycin practices among LTx providers internationally. A survey was distributed via the International Society for Heart and Lung Transplantation and completed by 103 respondents (15 countries). Azithromycin indications, timing, and dosing varied significantly, and 37 (36%) reported inconsistency even within their center. Thirty (29%) reported initiating azithromycin prophylactically (during initial transplant hospitalization). Of 73 others, only 10 (14%) reported waiting until CLAD diagnosis (with persistent ≥20% pulmonary function decline). Most initiated azithromycin after a CLAD risk-factor and/or event, including 59 (81%) for a persistent ≥10% decrement in FEV1, 32 (44%) for lymphocytic bronchiolitis, and 27 (37%) for bronchoalveolar lavage neutrophilia. Azithromycin prescribing patterns appear to vary significantly, and further study is needed to elucidate the optimal timing and indications for its initiation after LTx.

A multi-institutional review of outcomes in biopsy-proven acute invasive fungal sinusitis.

BACKGROUND: Acute invasive fungal sinusitis (AIFS) is a rare, aggressive infection occurring in immunocompromised patients. In this study we examined factors that affect survival in AIFS, and whether immune-stimulating therapies (IST) improve survival. METHODS: Pathology records of biopsy-proven AIFS were reviewed from 3 academic institutions from 1995 to 2016. Univariate and multivariate Cox regressions were performed at 1 and 3 months from diagnosis. RESULTS: One hundred fourteen patients were included; 45 received IST. In the univariate analysis, the following factors were associated with worse survival: hematologic malignancy (3-month hazard ratio [HR], 3.7; p = 0.01); recent chemotherapy (within 1 month of AIFS diagnosis) (3-month HR, 2.3; p = 0.02); recent bone marrow transplant (BMT) (3-month HR, 2.5; p = 0.02); and infection with atypical fungi (1-month HR, 3.1; p = 0.04). The following were associated with improved survival in univariate analysis: increasing A1c% (1-month HR, 0.7; p = 0.01) and surgical debridement (1-month HR, 0.1; p = 0.001). One third of patients with a hematologic malignancy had an absolute neutrophil count (ANC) >1000 at the time of diagnosis. ANC was not associated with prognosis in these patients. The following were associated with worse survival in multivariate analyses: hematologic malignancy; recent chemotherapy; atypical organisms; and cavernous sinus extension. In multivariate analyses, IST was associated with a 70% reduction in mortality at 1 month (p = 0.02). CONCLUSION: We presented the largest series of AIFS. Further studies are needed to examine the importance of ANC in diagnosis and prognosis. Patients diagnosed with atypical organisms may be at higher risk of death. IST likely improves short-term survival, but prospective studies are needed.