Potential Delays in Diagnosis of Idiopathic Pulmonary Fibrosis in Medicare Beneficiaries

Computer-Aided Pulmonary Fibrosis Detection Leveraging an Advanced Artificial Intelligence Triage and Notification Software

Background

Improvement in recognition and referral of pulmonary fibrosis (PF) is vital to improving patient outcomes within interstitial lung disease. We determined the performance metrics and processing time of an artificial intelligence triage and notification software, ScreenDx-LungFibrosis™, developed to improve detection of PF.

Methods

ScreenDx-LungFibrosis™ was applied to chest computed tomography (CT) scans from multisource data. Device output (+/- PF) was compared to clinical diagnosis (+/- PF), and diagnostic performance was evaluated. Primary endpoints included device sensitivity and specificity > 80% and processing time < 4.5 min.

Results

Of 3,018 patients included, PF was present in 22.9%. ScreenDx-LungFibrosis™ detected PF with a sensitivity and specificity of 91.3% (95% confidence interval (CI): 89.0-93.3%) and 95.1% (95% CI: 94.2-96.0%), respectively. Mean processing time was 27.6 s (95% CI: 26.0 - 29.1 s).

Conclusions

ScreenDx-LungFibrosis™ accurately and reliably identified PF with a rapid per-case processing time, underscoring its potential for transformative improvement in PF outcomes when routinely applied to chest CTs.

Assessing feasibility of targeted primary care referrals for patients with clinical suspicion of interstitial lung disease using lung ultrasound: a prospective case finding study. The potential benefits of LUS utilization

BACKGROUND

In Primary Health Care (PHC) many interstitial lung disease (ILD) cases may remain at diagnostic delay, due to their challenging presentation and the limited experience of general practitioners (GPs) in recognizing their early symptoms.

OBJECTIVE

We have designed a feasibility study to investigate early ILD case-finding competency between PHC and tertiary care.

METHODS

A cross-sectional prospective case-finding study was launched at two private health care centers of Heraklion, Crete, Greece, during nine months (2021-2022). After clinical assessment by GP, PHC attenders, who agreed to participate in the study, were referred to the Respiratory Medicine Department, University Hospital of Heraklion, Crete, underwent Lung Ultrasound (LUS) and those with an overall suspicion for ILDs underwent high resolution computed tomography (HRCT) scan. Descriptive statistics and chi-square tests were used. Multiple Poisson regression analysis was performed to explain positive LUS and HRCT decision with selected variables.

RESULTS

One hundred and nine patients out of 183 were finally included (54.1% females; mean age 61, SD: 8.3 years). Thirty-five (32.1%) were current smokers. Overall, two out of ten cases were assessed to need HRCT due to a moderate or high suspicion (19.3%; 95%CI 12.7, 27.4). However, in those who had dyspnea in relation to counterparts, a significantly higher percentage of patients with LUS findings (57.9% vs. 34.0%, p=0.013) was found, as in those who had crackles (100.0% vs. 44.2%, p= 0.005). Detected possible ILD provisional labelling cases were 6, and most importantly, 5 of those cases were considered highly suspicious for further evaluation based on LUS findings.

CONCLUSIONS

This is a feasibility study exploring potentials by combining data of medical history, basic auscultation skills, as crackles detection, and inexpensive and radiation-free imaging technique, such as LUS. Cases of ILD labeling may be hidden within PHC, sometimes, much before any clinical manifestation.

Screening for idiopathic pulmonary fibrosis using comorbidity signatures in electronic health records

Idiopathic pulmonary fibrosis (IPF) is a lethal fibrosing interstitial lung disease with a mean survival time of less than 5 years. Nonspecific presentation, a lack of effective early screening tools, unclear pathobiology of early-stage IPF and the need for invasive and expensive procedures for diagnostic confirmation hinder early diagnosis. In this study, we introduce a new screening tool for IPF in primary care settings that requires no new laboratory tests and does not require recognition of early symptoms. Using subtle comorbidity signatures identified from the history of medical encounters of individuals, we developed an algorithm, called the zero-burden comorbidity risk score for IPF (ZCoR-IPF), to predict the future risk of an IPF diagnosis. ZCoR-IPF was trained on a national insurance claims database and validated on three independent databases, comprising a total of 2,983,215 participants, with 54,247 positive cases. The algorithm achieved positive likelihood ratios greater than 30 at a specificity of 0.99 across different cohorts, for both sexes, and for participants with different risk states and history of confounding diseases. The area under the receiver-operating characteristic curve for ZCoR-IPF in predicting IPF exceeded 0.88 and was approximately 0.84 at 1 and 4 years before a conventional diagnosis, respectively. Thus, if adopted, ZCoR-IPF can potentially enable earlier diagnosis of IPF and improve outcomes of disease-modifying therapies and other interventions.

Potential interstitial lung abnormalities on chest X-rays prior to symptoms of idiopathic pulmonary fibrosis

Background

Idiopathic pulmonary fibrosis (IPF) often has significant diagnostic delay. At present it is not well-known what factors associate with time to diagnosis and if this is associated with survival after the diagnosis. There has also been increasing attention for interstitial lung abnormalities on chest CT-scans. In this study we assessed what factors associate with time to diagnosis in patients with IPF, and whether early stages of pulmonary fibrosis can be seen on chest X-rays prior to the start of symptoms.

Methods

In this retrospective study, 409 Dutch patients with IPF were included. Clinical characteristics, including patient demographics, medical history, time of start of symptoms, time of first visit to pulmonologist, and any previous radiographic imaging reports were collected from patient records.

Results

In 96 patients (23%) a chest X-ray was available that had been made prior to the start of symptoms (median of 50.5 months (IQR 26.3–83.3 months)), and this showed potential interstitial lung abnormalities in 56 patients (58%). The median time from the start of symptoms to the final diagnosis was 24.0 months (interquartile range 9.0–48.0 months). In a multivariate model that corrected for diffusion capacity of the lung for carbon monoxide, forced vital capacity, sex, and age at diagnosis, time to diagnosis did not associate with survival (hazard ratio 1.051 (95% CI 0.800–1.380; p = 0.72)).

Conclusions

There is a significant diagnostic delay for patients with IPF, but longer time to diagnosis did not associate with survival. Interstitial lung abnormalities were seen in more than half of the patients in whom a chest X-ray had been made prior to the start of symptoms. This illustrates that a computed tomography scan should be strongly considered for analysis of unexplained abnormalities on a chest X-ray. This could facilitate early detection and possibly prevention of disease progression for patients with pulmonary fibrosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02122-8.

Classification of Respiratory Conditions using Auscultation Sound

Management of respiratory conditions relies on timely diagnosis and institution of appropriate management. Computerized analysis and classification of breath sounds has a potential to enhance reliability and accuracy of diagnostic modality while making it suitable for remote monitoring, personalized uses, and self-management uses. In this paper, we describe and compare sound recognition models aimed at automatic diagnostic differentiation of healthy persons vs patients with COPD vs patients with pneumonia using deep learning approaches such as Multi-layer Perceptron Classifier (MLPClassifier) and Convolutional Neural Networks (CNN).Clinical Relevance-Healthcare providers and researchers interested in the field of medical sound analysis, specifically automatic detection/classification of auscultation sound and early diagnosis of respiratory conditions may benefit from this paper.

Patient Reported Experiences and Delays During the Diagnostic Pathway for Pulmonary Fibrosis: A Multinational European Survey

Introduction: Pulmonary fibrosis includes a spectrum of diseases and is incurable. There is a variation in disease course, but it is often progressive leading to increased breathlessness, impaired quality of life, and decreased life expectancy. Detection of pulmonary fibrosis is challenging, which contributes to considerable delays in diagnosis and treatment. More knowledge about the diagnostic journey from patients' perspective is needed to improve the diagnostic pathway. The aims of this study were to evaluate the time to diagnosis of pulmonary fibrosis, identify potential reasons for delays, and document patients emotions.

Methods: Members of European patient organisations, with a self-reported diagnosis of pulmonary fibrosis, were invited to participate in an online survey. The survey assessed the diagnostic pathway retrospectively, focusing on four stages: (1) time from initial symptoms to first appointment in primary care; (2) time to hospital referral; (3) time to first hospital appointment; (4) time to final diagnosis. It comprised open-ended and closed questions focusing on time to diagnosis, factors contributing to delays, diagnostic tests, patient emotions, and information provision.

Results: Two hundred and seventy three participants (214 idiopathic pulmonary fibrosis, 28 sarcoidosis, 31 other) from 13 countries responded. Forty percent of individuals took ≥1 year to receive a final diagnosis. Greatest delays were reported in stage 1, with only 50.2% making an appointment within 3 months. For stage 2, 73.3% reported a hospital referral within three primary care visits. However, 9.9% reported six or more visits. After referral, 76.9% of patients were assessed by a specialist within 3 months (stage 3) and 62.6% received a final diagnosis within 3 months of their first hospital visit (stage 4). Emotions during the journey were overall negative. A major need for more information and support during and after the diagnostic process was identified.

Conclusion: The time to diagnose pulmonary fibrosis varies widely across Europe. Delays occur at each stage of the diagnostic pathway. Raising awareness about pulmonary fibrosis amongst the general population and healthcare workers is essential to shorten the time to diagnosis. Furthermore, there remains a need to provide patients with sufficient information and support at all stages of their diagnostic journey.

Time to diagnosis of idiopathic pulmonary fibrosis in the IPF-PRO Registry

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with high mortality. Patient characteristics associated with diagnostic delays are not well described.

METHODS

Subjects who had not been diagnosed with IPF prior to referral and received a new diagnosis of IPF at an enrolling centre for the IPF-PRO (Idiopathic Pulmonary Fibrosis Prospective Outcomes) Registry were characterised as having a longer (>1 year) or shorter (≤1 year) time from symptom onset to diagnosis and from first imaging evidence of fibrosis to diagnosis. Patient characteristics, evaluations and time to death or lung transplant were compared between these cohorts.

RESULTS

Among 347 patients with a symptom onset date, 49% were diagnosed with IPF >1 year after symptom onset. These patients were slightly younger and had more cardiac comorbidities than patients diagnosed ≤1 year after symptom onset. Among 454 patients with a date for imaging evidence of fibrosis, 78% were diagnosed with IPF ≤1 year later. A greater proportion of patients with >1 year versus ≤1 year from imaging evidence of fibrosis to diagnosis had cardiac comorbidities and gastro-oesophageal reflux. There was no significant difference in time to death or lung transplant between groups by time to diagnosis.

CONCLUSIONS

The time from symptom onset to diagnosis remains over 1 year in approximately half of the patients with IPF, but once imaging evidence is obtained, most of the patients are diagnosed within a year. Cardiac conditions and gastro-oesophageal disorders were more commonly reported in patients with a longer time to diagnosis.

Clinical course of IPF in Italian patients during 12 months of observation: results from the FIBRONET observational study

Background

FIBRONET was an observational, multicentre, prospective cohort study investigating the baseline characteristics, clinical course of disease and use of antifibrotic treatment in Italian patients with idiopathic pulmonary fibrosis (IPF).

Methods

Patients aged ≥ 40 years diagnosed with IPF within the previous 3 months at 20 Italian centres were consecutively enrolled and followed up for 12 months, with evaluations at 3, 6, 9 and 12 months. The primary objective was to describe the clinical course of IPF over 12 months of follow-up, including changes in lung function measured by % predicted forced vital capacity (FVC% predicted).

Results

209 patients (82.3% male, mean age 69.54 ± 7.43 years) were enrolled. Mean FVC% predicted was relatively preserved at baseline (80.01%). The mean time between IPF diagnosis and initiation of antifibrotic therapy was 6.38 weeks; 72.3% of patients received antifibrotic therapy within the first 3 months of follow-up, and 83.9% within 12 months of follow-up. Mean FVC% predicted was 80.0% at baseline and 82.2% at 12 months, and 47.4% of patients remained stable (i.e. had no disease progression) in terms of FVC% predicted during the study.

Conclusions

FIBRONET is the first prospective, real-life, observational study of patients with IPF in Italy. The short time between diagnosis and initiation of antifibrotic therapy, and the stable lung function between baseline and 12 months, suggest that early diagnosis and prompt initiation of antifibrotic therapy may preserve lung function in patients with IPF.

Trial registration: NCT02803580

Time taken from primary care referral to a specialist centre diagnosis of idiopathic pulmonary fibrosis: an opportunity to improve patient outcomes?

The care of patients with idiopathic pulmonary fibrosis (IPF) has been transformed by the widespread approval of antifibrotic therapies [1]. Within primary care-based healthcare systems, the diagnosis of IPF and commencement of antifibrotic therapy typically requires a patient referral from a primary care physician to a respiratory physician in secondary care, with referral then made to a specialist interstitial lung disease (ILD) centre [2]. Following ILD centre review and multidisciplinary team (MDT) discussion, a diagnosis of IPF is made and antifibrotic therapy may be commenced.

For patients with IPF, length of time in healthcare systems prior to review in an ILD clinic reflects disease severity and may impact upon patient outcomehttps://bit.ly/2TkO26r

Are infectious diseases risk factors for sarcoidosis or a result of reverse causation? Findings from a population-based nested case-control study

Findings from molecular studies suggesting that several infectious agents cause sarcoidosis are intriguing yet conflicting and likely biased due to their cross-sectional design. As done in other inflammatory diseases to overcome this issue, prospectively-collected register data could be used, but reverse causation is a threat when the onset of disease is difficult to establish. We investigated the association between infectious diseases and sarcoidosis to understand if they are etiologically related. We conducted a nested case-control study (2009-2013) using incident sarcoidosis cases from the Swedish National Patient Register (n = 4075) and matched general population controls (n = 40,688). Infectious disease was defined using inpatient/outpatient visits and/or antimicrobial dispensations starting 3 years before diagnosis/matching. Adjusted odds ratios (aOR) of sarcoidosis were estimated using conditional logistic regression and tested for robustness assuming the presence of reverse causation bias. The aOR of sarcoidosis associated with history of infectious disease was 1.19 (95% confidence interval [CI] 1.09, 1.29; 21% vs. 16% exposed cases and controls, respectively). Upper respiratory and ocular infections conferred the highest OR. Findings were similar when we altered the infection definition or varied the infection-sarcoidosis latency period (1-7 years). In bias analyses assuming one in 10 infections occurred because of preclinical sarcoidosis, the observed association was completely attenuated (aOR 1.02; 95% CI 0.90, 1.15). Our findings, likely induced by reverse causation due to preclinical sarcoidosis, do not support the hypothesis that common symptomatic infectious diseases are etiologically linked to sarcoidosis. Caution for reverse causation bias is required when the real disease onset is unknown.

Diagnostic test interpretation and referral delay in patients with interstitial lung disease

Background

Diagnostic delays are common in patients with interstitial lung disease (ILD). A substantial percentage of patients experience a diagnostic delay in the primary care setting, but the factors underpinning this observation remain unclear. In this multi-center investigation, we assessed ILD reporting on diagnostic test interpretation and its association with subsequent pulmonology referral by a primary care physician (PCP).

Methods

A retrospective cohort analysis of patients referred to the ILD programs at UC-Davis and University of Chicago by a PCP within each institution was performed. Computed tomography (CT) of the chest and abdomen and pulmonary function test (PFT) were reviewed to identify the date ILD features were first present and determine the time from diagnostic test to pulmonology referral. The association between ILD reporting on diagnostic test interpretation and pulmonology referral was assessed, as was the association between years of diagnostic delay and changes in fibrotic features on longitudinal chest CT.

Results

One hundred and forty-six patients were included in the final analysis. Prior to pulmonology referral, 66% (n = 97) of patients underwent chest CT, 15% (n = 21) underwent PFT and 15% (n = 21) underwent abdominal CT. ILD features were reported on 84, 62 and 33% of chest CT, PFT and abdominal CT interpretations, respectively. ILD reporting was associated with shorter time to pulmonology referral when undergoing chest CT (1.3 vs 15.1 months, respectively; p = 0.02), but not PFT or abdominal CT. ILD reporting was associated with increased likelihood of pulmonology referral within 6 months of diagnostic test when undergoing chest CT (rate ratio 2.17, 95% CI 1.03–4.56; p = 0.04), but not PFT or abdominal CT. Each year of diagnostic delay was associated with a 1.8% increase in percent fibrosis on chest CT. Patients with documented dyspnea had shorter time to chest CT acquisition and pulmonology referral than patients with documented cough and lung crackles.

Conclusions

Determinants of ILD diagnostic delays in the primary care setting include underreporting of ILD features on diagnostic testing and prolonged time to pulmonology referral even when ILD is reported. Interventions to modulate these factors may reduce ILD diagnostic delays in the primary care setting.