DYNamic Assessment of Multi-Organ level dysfunction in patients recovering from COVID-19: DYNAMO COVID-19.

We evaluated the impacts of COVID-19 on multi-organ and metabolic function in patients following severe hospitalised infection compared to controls. Patients (n = 21) without previous diabetes, cardiovascular or cerebrovascular disease were recruited 5-7 months post-discharge alongside controls (n = 10) with similar age, sex and body mass. Perceived fatigue was estimated (Fatigue Severity Scale) and the following were conducted: oral glucose tolerance (OGTT) alongside whole-body fuel oxidation, validated magnetic resonance imaging and spectroscopy during resting and supine controlled exercise, dual-energy X-ray absorptiometry, short physical performance battery (SPPB), intra-muscular electromyography, quadriceps strength and fatigability, and daily step-count. There was a greater insulin response (incremental area under the curve, median (inter-quartile range)) during the OGTT in patients [18,289 (12,497-27,448) mIU/min/L] versus controls [8655 (7948-11,040) mIU/min/L], P < 0.001. Blood glucose response and fasting and post-prandial fuel oxidation rates were not different. This greater insulin resistance was not explained by differences in systemic inflammation or whole-body/regional adiposity, but step-count (P = 0.07) and SPPB scores (P = 0.004) were lower in patients. Liver volume was 28% greater in patients than controls, and fat fraction adjusted liver T1, a measure of inflammation, was raised in patients. Patients displayed greater perceived fatigue scores, though leg muscle volume, strength, force-loss, motor unit properties and post-exercise muscle phosphocreatine resynthesis were comparable. Further, cardiac and cerebral architecture and function (at rest and on exercise) were not different. In this cross-sectional study, individuals without known previous morbidity who survived severe COVID-19 exhibited greater insulin resistance, pointing to a need for physical function intervention in recovery.

Readmission following hospital admission for community-acquired pneumonia in England.

INTRODUCTION: Readmission rates following hospital admission with community-acquired pneumonia (CAP) have increased in the UK over the past decade. The aim of this work was to describe the cohort of patients with emergency 30-day readmission following hospitalisation for CAP in England and explore the reasons for this. METHODS: A retrospective analysis of cases from the British Thoracic Society national adult CAP audit admitted to hospitals in England with CAP between 1 December 2018 and 31 January 2019 was performed. Cases were linked with corresponding patient level data from Hospital Episode statistics, providing data on the primary diagnosis treated during readmission and mortality. Analyses were performed describing the cohort of patients readmitted within 30 days, reasons for readmission and comparing those readmitted and primarily treated for pneumonia with other diagnoses. RESULTS: Of 8136 cases who survived an index admission with CAP, 1304 (15.7%) were readmitted as an emergency within 30 days of discharge. The main problems treated on readmission were pneumonia in 516 (39.6%) patients and other respiratory disorders in 284 (21.8%). Readmission with pneumonia compared with all other diagnoses was associated with significant inpatient mortality (15.9% vs 6.5%; aOR 2.76, 95% CI 1.86 to 4.09, p<0.001). A diagnosis of hospital-acquired infection was more frequent in readmissions treated for pneumonia than other diagnoses (22.1% vs 3.9%, p<0.001). CONCLUSION: Pneumonia is the most common condition treated on readmission following hospitalisation with CAP and carries a higher mortality than both the index admission or readmission due to other diagnoses. Strategies to reduce readmissions due to pneumonia are required.

Association between antidepressants with pneumonia and exacerbation in patients with COPD: a self-controlled case series (SCCS).

OBJECTIVE: To assess whether antidepressant prescriptions are associated with an increased risk of pneumonia and chronic obstructive pulmonary disease (COPD) exacerbation. METHODS: A self-controlled case series was performed to investigate the rates of pneumonia and COPD exacerbation during periods of being exposed to antidepressants compared with non-exposed periods. Patients with COPD with pneumonia or COPD exacerbation and at least one prescription of antidepressant were ascertained from The Health Improvement Network in the UK. Incidence rate ratios (IRR) and 95% CI were calculated for both outcomes. RESULTS: Of 31 253 patients with COPD with at least one antidepressant prescription, 1969 patients had pneumonia and 18 483 had a COPD exacerbation. The 90-day risk period following antidepressant prescription was associated with a 79% increased risk of pneumonia (age-adjusted IRR 1.79, 95% CI 1.54 to 2.07). These associations then disappeared once antidepressants were discontinued. There was a 16% (age-adjusted IRR 1.16, 95% CI 1.13 to 1.20) increased risk of COPD exacerbation within the 90 days following antidepressant prescription. This risk persisted and slightly increased in the remainder period ((age-adjusted IRR 1.38, 95% CI 1.34 to 1.41), but diminished after patients discounted the treatment. CONCLUSION: Antidepressants were associated with an increased risk of both pneumonia and exacerbation in patients with COPD, with the risks diminished on stopping the treatment. These findings suggest a close monitoring of antidepressant prescription side effects and consideration of non-pharmacological interventions.

Effects of tobacco smoking on recurrent hospitalisation with pneumonia: a population-based cohort study.

The incidence of and risk factors for recurrent hospitalisation for pneumonia were investigated using data from Hospital Episode Statistics, linked to a UK primary care database. Within 90 days and 1 year of follow-up, 1733 (3.1%) and 5064 (9.0%), developed recurrent pneumonia respectively. Smoking status at the time of hospitalisation with index pneumonia was associated with the risk of readmission with recurrent pneumonia within a year of discharge: current versus never smokers: adjusted subhazard ratio (sHR) 1.42, 95% CI 1.32 to 1.53, p<0.001, and ex smokers versus never smokers: adjusted sHR 1.24, 95% CI 1.15 to 1.34, p<0.001. Other independent risk factors associated with recurrent pneumonia were age, gender, deprivation and underlying comorbidities.

Dynamic early warning scores for predicting clinical deterioration in patients with respiratory disease.

BACKGROUND: The National Early Warning Score-2 (NEWS-2) is used to detect patient deterioration in UK hospitals but fails to take account of the detailed granularity or temporal trends in clinical observations. We used data-driven methods to develop dynamic early warning scores (DEWS) to address these deficiencies, and tested their accuracy in patients with respiratory disease for predicting (1) death or intensive care unit admission, occurring within 24 h (D/ICU), and (2) clinically significant deterioration requiring urgent intervention, occurring within 4 h (CSD). METHODS: Clinical observations data were extracted from electronic records for 31,590 respiratory in-patient episodes from April 2015 to December 2020 at a large acute NHS Trust. The timing of D/ICU was extracted for all episodes. 1100 in-patient episodes were annotated manually to record the timing of CSD, defined as a specific event requiring a change in treatment. Time series features were entered into logistic regression models to derive DEWS for each of the clinical outcomes. Area under the receiver operating characteristic curve (AUROC) was the primary measure of model accuracy. RESULTS: AUROC (95% confidence interval) for predicting D/ICU was 0.857 (0.852-0.862) for NEWS-2 and 0.906 (0.899-0.914) for DEWS in the validation data. AUROC for predicting CSD was 0.829 (0.817-0.842) for NEWS-2 and 0.877 (0.862-0.892) for DEWS. NEWS-2 ≥ 5 had sensitivity of 88.2% and specificity of 54.2% for predicting CSD, while DEWS ≥ 0.021 had higher sensitivity of 93.6% and approximately the same specificity of 54.3% for the same outcome. Using these cut-offs, 315 out of 347 (90.8%) CSD events were detected by both NEWS-2 and DEWS, at the time of the event or within the previous 4 h; 12 (3.5%) were detected by DEWS but not by NEWS-2, while 4 (1.2%) were detected by NEWS-2 but not by DEWS; 16 (4.6%) were not detected by either scoring system. CONCLUSION: We have developed DEWS that display greater accuracy than NEWS-2 for predicting clinical deterioration events in patients with respiratory disease. Prospective validation studies are required to assess whether DEWS can be used to reduce missed deteriorations and false alarms in real-life clinical settings.

Phenotypic and functional translation of IL33 genetics in asthma.

BACKGROUND: Asthma is a complex disease with multiple phenotypes that may differ in disease pathobiology and treatment response. IL33 single nucleotide polymorphisms (SNPs) have been reproducibly associated with asthma. IL33 levels are elevated in sputum and bronchial biopsies of patients with asthma. The functional consequences of IL33 asthma SNPs remain unknown. OBJECTIVE: This study sought to determine whether IL33 SNPs associate with asthma-related phenotypes and with IL33 expression in lung or bronchial epithelium. This study investigated the effect of increased IL33 expression on human bronchial epithelial cell (HBEC) function. METHODS: Association between IL33 SNPs (Chr9: 5,815,786-6,657,983) and asthma phenotypes (Lifelines/DAG [Dutch Asthma GWAS]/GASP [Genetics of Asthma Severity & Phenotypes] cohorts) and between SNPs and expression (lung tissue, bronchial brushes, HBECs) was done using regression modeling. Lentiviral overexpression was used to study IL33 effects on HBECs. RESULTS: We found that 161 SNPs spanning the IL33 region associated with 1 or more asthma phenotypes after correction for multiple testing. We report a main independent signal tagged by rs992969 associating with blood eosinophil levels, asthma, and eosinophilic asthma. A second, independent signal tagged by rs4008366 presented modest association with eosinophilic asthma. Neither signal associated with FEV1, FEV1/forced vital capacity, atopy, and age of asthma onset. The 2 IL33 signals are expression quantitative loci in bronchial brushes and cultured HBECs, but not in lung tissue. IL33 overexpression in vitro resulted in reduced viability and reactive oxygen species-capturing of HBECs, without influencing epithelial cell count, metabolic activity, or barrier function. CONCLUSIONS: We identify IL33 as an epithelial susceptibility gene for eosinophilia and asthma, provide mechanistic insight, and implicate targeting of the IL33 pathway specifically in eosinophilic asthma.

Risk of osteoporosis and fragility fractures in asthma due to oral and inhaled corticosteroids: two population-based nested case-control studies.

BACKGROUND: Inhaled (ICS) and oral (OCS) corticosteroids are used widely in asthma; however, the risk of osteoporosis and fragility fracture (FF) due to corticosteroids in asthma is not well-established. METHODS: We conducted two nested case-control studies using linked data from the Clinical Practice Research Datalink (CPRD) and Hospital Episode Statistics (HES) databases. Using an asthma cohort, we separately identified patients with osteoporosis or FF and gender-, age- and practice-matched controls. Conditional logistic regression was used to determine the association between ICS and OCS exposure, and the risk of osteoporosis or FF. The prevalence of patients receiving at least one bisphosphonate was also calculated. RESULTS: There was a dose-response relationship between both cumulative dose and number of OCS/ICS prescriptions within the previous year, and risk of osteoporosis or FF. After adjusting for confounders, people receiving more OCS prescriptions (≥9 vs 0) had a 4.50 (95% CI 3.21 to 6.11) and 2.16 (95% CI 1.56 to 3.32) increased risk of osteoporosis and FF, respectively. For ICS (≥11 vs 0) the ORs were 1.60 (95% CI 1.22 to 2.10) and 1.31 (95% CI 1.02 to 1.68). The cumulative dose had a similar impact, with those receiving more OCS or ICS being at greater risk. The prevalence of patients taking ≥9 OCS and at least one bisphosphonate prescription was just 50.6% and 48.4% for osteoporosis and FF, respectively. CONCLUSIONS: The findings suggest that exposure to OCS or ICS is an independent risk factors for bone health in patients with asthma. Steroid administration at the lowest possible level to maintain asthma control is recommended.

Incidence of osteoporosis and fragility fractures in asthma: a UK population-based matched cohort study.

INTRODUCTION: Osteoporosis and fragility fractures are associated with corticosteroids which are the mainstay treatment for asthma; however, these bone comorbidities within asthma need to be better described. METHODS: A matched cohort study was conducted using the UK Clinical Practice Research Database (CPRD). Adults with an incident asthma code were identified and matched, with up to four randomly selected people without asthma, by age, sex and practice. Osteoporosis and fragility fracture incidence rates were calculated, and Cox regression was performed comparing hazard rates to the general population. We report the impact of age, sex, glucocorticoids and the risk of specific fractures. RESULTS: Patients with asthma had a higher risk of osteoporosis (adjusted hazard ratio (aHR) 1.18, 95% CI 1.13-1.23) and were 12% (aHR 1.12, 95% CI 1.07-1.16) more likely to sustain fragility fractures than the general population. Age modified the effect of asthma on osteoporosis and fragility fractures, such that the effect was stronger in younger people (pinteraction<0.0001). The vertebra (aHR 1.40, 95% CI 1.33-1.48) and forearm/wrist (aHR 1.27, 95% CI 1.22-1.32) were the sites linked with a larger incidence. A dose-response relationship between oral corticosteroids (OCS) and osteoporosis was observed, whereas the risk of fragility fractures increased in those with six or more OCS courses per year. Regular use of inhaled corticosteroids (ICS) increased the risk of both bone conditions. CONCLUSIONS: Patients with asthma are more likely to develop osteoporosis or sustain fragility fractures than the general population, with a particular concern in younger people and those more frequently using OCS and ICS.

A low exhaled nitric oxide level excludes a short-term benefit from inhaled corticosteroids in suspected asthma: A randomized placebo-controlled trial.

BACKGROUND AND OBJECTIVE: Fractional exhaled nitric oxide (FeNO) is a non-invasive biomarker that reflects IL-4/IL-13 production and therefore represents T2 allergic inflammation. FeNO has previously been used to guide inhaled corticosteroid (ICS) treatment in asthma. The purpose of this study was to determine if a low FeNO (≤27 ppb) could be used to reliably identify patients with symptoms suggestive of asthma who would not benefit from initiating treatment with an ICS. METHODS: A total of 180 steroid-naïve adults with healthcare professional suspected asthma and an FeNO of ≤27 ppb were randomized to receive either 400 mcg of budesonide or placebo daily for 3 months. The primary outcome was the difference in the Asthma Control Questionnaire 7 (ACQ7) between treatment groups and the study was powered to determine equivalence. Secondary outcomes were the difference in FEV1 , Medical Research Council and Leicester Cough Questionnaire scores. RESULTS: One hundred and thirty-four patients (68 budesonide and 66 placebo) completed the study and were included in the analysis. The between-group mean difference in ACQ7 from baseline to the end of the study was -0.25 and the 95% CI around this difference was -0.004 to 0.495 confirming equivalence (p < 0.05). Differences in forced expiratory volume over 1 s and other secondary outcomes were also small and clinically unimportant. CONCLUSION: The results of this study suggest that steroid-naïve patients with symptoms suggestive of asthma and an FeNO ≤ 27 ppb are unlikely to benefit from initiating treatment with an ICS over 3 months. However, further research is recommended to confirm these findings before withholding ICS treatment.

Impact of COVID-19 on corticosteroids and antibiotics prescribing in England: an interrupted time series analysis.

Inhaled corticosteroids (ICS), prednisolone and antibiotics all play a crucial role in the management of respiratory diseases. The aim of this study was to analyse whether the declaration of the COVID-19 pandemic affected prescribing rates, as public health measures were implemented to reduce transmission of SARS-CoV-2. Monthly practise-level prescribing data published by NHS Digital were analysed. At the point, the COVID-19 outbreak was declared a pandemic, ICS prescriptions rose significantly. This was followed by a decrease in ICS and prednisolone prescribing in the following months. There was no difference in the antibiotic prescribing trend.

Effectiveness of the 23-valent pneumococcal polysaccharide vaccine against vaccine serotype pneumococcal pneumonia in adults: A case-control test-negative design study.

BACKGROUND: Vaccination with the 23-valent pneumococcal polysaccharide vaccine (PPV23) is available in the United Kingdom to adults aged 65 years or older and those in defined clinical risk groups. We evaluated the vaccine effectiveness (VE) of PPV23 against vaccine-type pneumococcal pneumonia in a cohort of adults hospitalised with community-acquired pneumonia (CAP). METHODS AND FINDINGS: Using a case-control test-negative design, a secondary analysis of data was conducted from a prospective cohort study of adults (aged ≥16 years) with CAP hospitalised at 2 university teaching hospitals in Nottingham, England, from September 2013 to August 2018. The exposure of interest was PPV23 vaccination at any time point prior to the index admission. A case was defined as PPV23 serotype-specific pneumococcal pneumonia and a control as non-PPV23 serotype pneumococcal pneumonia or nonpneumococcal pneumonia. Pneumococcal serotypes were identified from urine samples using a multiplex immunoassay or from positive blood cultures. Multivariable logistic regression was used to derive adjusted odds of case status between vaccinated and unvaccinated individuals; VE estimates were calculated as (1 - odds ratio) × 100%. Of 2,357 patients, there were 717 PPV23 cases (48% vaccinated) and 1,640 controls (54.5% vaccinated). The adjusted VE (aVE) estimate against PPV23 serotype disease was 24% (95% CI 5%-40%, p = 0.02). Estimates were similar in analyses restricted to vaccine-eligible patients (n = 1,768, aVE 23%, 95% CI 1%-40%) and patients aged ≥65 years (n = 1,407, aVE 20%, 95% CI -5% to 40%), but not in patients aged ≥75 years (n = 905, aVE 5%, 95% CI -37% to 35%). The aVE estimate in relation to PPV23/non-13-valent pneumococcal conjugate vaccine (PCV13) serotype pneumonia (n = 417 cases, 43.7% vaccinated) was 29% (95% CI 6%-46%). Key limitations of this study are that, due to high vaccination rates, there was a lack of power to reject the null hypothesis of no vaccine effect, and that the study was not large enough to allow robust subgroup analysis in the older age groups. CONCLUSIONS: In the setting of an established national childhood PCV13 vaccination programme, PPV23 vaccination of clinical at-risk patient groups and adults aged ≥65 years provided moderate long-term protection against hospitalisation with PPV23 serotype pneumonia. These findings suggest that PPV23 vaccination may continue to have an important role in adult pneumococcal vaccine policy, including the possibility of revaccination of older adults.

Admission to hospital in the UK at a weekend does not influence the prognosis of adults with community-acquired pneumonia.

Outcomes for adults with community-acquired pneumonia (CAP) admitted to hospital at the weekend were compared with those admitted during weekdays using data from the British Thoracic Society national CAP audits. Of 31 400 cases, 40.7% were weekend admissions; these patients were older (mean age 72 vs 71.3 years, p=0.001) and more likely to have high severity CAP (28.9% vs 27.1%, p trend 0.003) but had slightly lower adjusted 30-day inpatient mortality (aOR 0.94 95% CI 0.88 to 1.01) compared with those admitted during weekdays. More patients in the weekend group received antibiotics within 4 hours of admission (70.3% vs 68.7%, aOR 1.07 95% CI 1.01 to 1.12). We did not observe increased mortality for adults admitted at the weekend with CAP.

Pneumococcal serotype trends, surveillance and risk factors in UK adult pneumonia, 2013-18.

BACKGROUND: Changes over the last 5 years (2013-18) in the serotypes implicated in adult pneumococcal pneumonia and the patient groups associated with vaccine-type disease are largely unknown. METHODS: We conducted a population-based prospective cohort study of adults admitted to two large university hospitals with community-acquired pneumonia (CAP) between September 2013 and August 2018. Pneumococcal serotypes were identified using a novel 24-valent urinary monoclonal antibody assay and from blood cultures. Trends in incidence rates were compared against national invasive pneumococcal disease (IPD) data. Persons at risk of vaccine-type pneumonia (pneumococcal conjugate vaccine (PCV)13 and pneumococcal polysaccharide vaccine (PPV)23) were determined from multivariate analyses. FINDINGS: Of 2934 adults hospitalised with CAP, 1075 (36.6%) had pneumococcal pneumonia. The annual incidence of pneumococcal pneumonia increased from 32.2 to 48.2 per 100 000 population (2013-18), predominantly due to increases in PCV13non7-serotype and non-vaccine type (NVT)-serotype pneumonia (annual incidence rate ratio 1.12, 95% CI 1.04 to 1.21 and 1.19, 95% CI 1.10 to 1.28, respectively). Incidence trends were broadly similar to IPD data. PCV13non7 (56.9% serotype 3) and PPV23non13 (44.1% serotype 8) serotypes were identified in 349 (32.5%) and 431 (40.1%) patients with pneumococcal pneumonia, respectively. PCV13-serotype pneumonia (dominated by serotype 3) was more likely in patients in the UK pneumococcal vaccination clinical risk group (adjusted OR (aOR) 1.73, 95% CI 1.31 to 2.28) while PPV23-serotype pneumonia was more likely in patients outside the clinical risk group (aOR 1.54, 95% CI 1.13 to 2.10). INTERPRETATION: The incidence of pneumococcal CAP is increasing, predominantly due to NVT serotypes and serotype 3. PPV23-serotype pneumonia is more likely in adults outside currently identified clinical risk groups.

Patient-reported outcome measures in the recovery of adults hospitalised with community-acquired pneumonia: a systematic review.

Symptomatic and functional recovery are important patient-reported outcome measures (PROMs) in community-acquired pneumonia (CAP) that are increasingly used as trial end-points. This systematic review summarises the literature on PROMs in CAP.Comprehensive searches in accordance with the PRISMA statement were conducted to March 2017. Eligible studies included adults discharged from hospital following confirmed CAP and reporting PROMs.15 studies (n=5644 patients) were included; most were of moderate quality. Studies used a wide range of PROMs and assessment tools. At 4-6 weeks post-discharge, the commonest symptom reported was fatigue (45.0-72.6% of patients, three studies), followed by cough (35.3-69.7%) and dyspnoea (34.2-67.1%); corresponding values from studies restricted by age <65 years (two studies) were lower: fatigue 12.1-25.7%, cough 19.9-31.9% and dyspnoea 16.8-27.5%. Functional impairment 4 weeks post-discharge was reported in 18-51% of patients (two studies), while median time to return to normal activities was between 15 and 28 days (three studies).Substantial morbidity is reported by patients up to 6 weeks post-discharge. There is weak methodological consistency across existing studies. A core set of PROMs for use in future studies is suggested.

Risk of fall in patients with COPD.

A matched cohort study was conducted to determine the incidence of falls in patients following a diagnosis of COPD using a UK primary care database. 44 400 patients with COPD and 175 545 non-COPD subjects were identified. The incidence rate of fall per 1000 person-years in patients with COPD was higher (44.9; 95% CI 44.1 to 45.8) compared with non-COPD subjects (24.1; 95% CI 23.8 to 24.5) (P<0.0001). Patients with COPD were 55% more likely to have an incident record of fall than non-COPD subjects (adjusted HR, 1.55; 95% CI 1.50 to 1.59). The greater falls risk in patients with COPD needs consideration and modifiable factors addressed.

Adults miscoded and misdiagnosed as having pneumonia: results from the British Thoracic Society pneumonia audit.

A key objective of the British Thoracic Society national community-acquired pneumonia (CAP) audit was to determine the clinical characteristics and outcomes of hospitalised adults given a primary discharge code of pneumonia but who did not fulfil accepted diagnostic criteria for pneumonia. Adults miscoded as having pneumonia (n=1251) were older compared with adults with CAP (n=6660) (median 80 vs 78 years, p<0.001) and had more comorbid disease, significantly fewer respiratory symptoms (fever, cough, dyspnoea, pleuritic pain), more constitutional symptoms (general deterioration, falls) and significantly lower 30-day inpatient mortality (14.3% vs 17.0%, adjusted OR 0.75, p=0.003).

Timing of onset of symptoms in people with idiopathic pulmonary fibrosis.

Little is known about when symptoms of idiopathic pulmonary fibrosis first develop. We identified incident cases of idiopathic pulmonary fibrosis-clinical syndrome (IPF-CS) from a UK primary care database and assessed the frequency of consultations for common symptoms in the 5 years prior to diagnosis. 1671 cases were identified with 5 years of data prior to diagnosis. Breathlessness was the most common symptom, followed by cough. Cases were significantly more likely than controls to experience these symptoms (p<0.001), even 4-5 years before diagnosis (OR for breathlessness for this period 2.79, 95% CI 2.13 to 3.65). This suggests that some patients with IPF may be symptomatic for more than 5 years before diagnosis.

In-Hospital Mortality after Surgical Lung Biopsy for Interstitial Lung Disease in the United States. 2000 to 2011.

RATIONALE: Surgical lung biopsy can help to determine a specific diagnosis in interstitial lung disease but has associated risks. Most currently available mortality data are derived from case series and may not be generalizable to broader populations. OBJECTIVES: To assess in-hospital mortality after surgical lung biopsy for interstitial lung disease in a national secondary care dataset from the United States. METHODS: Data were obtained from the 2000-2011 Nationwide Inpatient Sample. Cases were identified using International Classification of Diseases codes for interstitial lung disease and surgical lung biopsies. Lung resections and cases of lung cancer were excluded. Weighted data were used to estimate numbers of biopsies nationwide and in-hospital mortality, and multivariable logistic regression was used to adjust for sex, age, geographic region, comorbidity, type of operation, and provisional diagnosis. MEASUREMENTS AND MAIN RESULTS: We estimated there to be around 12,000 surgical lung biopsies performed annually for interstitial lung disease in the United States, two-thirds of which were performed electively. In-hospital mortality was 1.7% for elective procedures but significantly higher for nonelective procedures (16.0%). Male sex, increasing age, increasing comorbidity, open surgery, and a provisional diagnosis of idiopathic pulmonary fibrosis or connective tissue disease-related interstitial lung disease were risk factors for increased mortality. CONCLUSIONS: In-hospital mortality after elective surgical lung biopsy for interstitial lung disease is just under 2% but significantly higher for nonelective procedures. Identified risk factors for death should be taken into account when counseling patients on whether to pursue a histologic diagnosis.