Optimizing the Diagnostic Journey in Interstitial Lung Disease: The OPTIMIZE-ILD-1 Trial

Official title

OPTIMIZE-ILD-1: A Randomized, Pragmatic, Parallel-Group Trial Evaluating the Impact of an Optimized Diagnostic Circuit on Time to Diagnosis in Patients With Suspected Interstitial Lung Disease

Overview

The OPTIMIZE-ILD-1 trial is a prospective, randomized, open-label clinical trial designed to evaluate the impact of a coordinated diagnostic pathway on patients with suspected interstitial lung disease (ILD). In routine clinical practice, diagnostic workflows for ILD are frequently fragmented, involving multiple independent appointments that can lead to significant delays and increased burden for patients and caregivers. This study compares the standard diagnostic pathway against an optimized circuit where core diagnostic procedures-such as high-resolution CT, pulmonary function tests, and laboratory panels-are pre-bundled and scheduled within a coordinated and compressed timeframe. All eligible patients referred for suspected ILD are included consecutively to ensure a pragmatic, real-world representation of the referral population. The primary objective is to measure the time to diagnostic communication, defined as the duration from randomization to the date the patient is formally informed of the final diagnosis following a multidisciplinary team (MDT) consensus. Secondary objectives include assessing the time to MDT diagnosis, the time to treatment initiation (when clinically indicated), socioeconomic cost-burden, and the environmental carbon footprint of the diagnostic journey. Furthermore, the study evaluates health-related quality of life, psychological distress, and clinical frailty, while exploring factors such as language proficiency as determinants of diagnostic equity. Caregiver-related outcomes, including burden and experience measures, are contingent upon the presence of a primary caregiver and the provision of their independent informed consent. The design of this protocol was informed by a patient focus group and is officially endorsed by the 'AIRE' Associació Catalana de Malalts i Trasplantats Pulmonars, ensuring a patient-centered approach that prioritizes the diagnostic journey's efficiency and human impact.

Detailed description

The primary endpoint of this study is the time to diagnostic communication, defined as the interval from randomization to the date when the final diagnosis is formally communicated to the patient following multidisciplinary team (MDT) consensus. Interstitial lung diseases (ILD) require a complex, multidimensional evaluation involving radiology, pulmonary function testing, and clinical assessment; however, fragmented scheduling in routine care often delays diagnosis and exacerbates inequities. OPTIMIZE-ILD-1 is a single-center, prospective, randomized trial with 1:1 allocation.

To ensure a balanced representation of clinical entry routes and phenotypes, randomization is stratified into three groups: 1) Primary Care referral without a pre-existing autoimmune disease; 2) Specialized Care referral without a pre-existing autoimmune disease; 3) referral with a pre-existing autoimmune disease, from any source. The intervention streamlines the coordination of existing diagnostic steps-including high-resolution chest CT, complete pulmonary function tests, and comprehensive laboratory panels-by clustering them into a coordinated workflow designed to be completed in the minimum number of hospital visits possible, without modifying clinical content or prioritization rules.

Secondary outcomes evaluate the pathway's efficiency and economic impact, including time to MDT diagnosis, time to treatment initiation (where clinically indicated), and the socioeconomic cost-burden for the family unit, which accounts for direct logistical expenses, productivity loss, and hospital operational inefficiencies. Additionally, the environmental impact is quantified via the diagnostic journey's carbon footprint. Patient-centered metrics are captured through validated instruments: EQ-5D-5L and K-BILD for health-related quality of life; GAD-7 for anxiety and PHQ-9 for depression; the Oslo-3 Social Support Scale for perceived social support; the Social-Familial Evaluation Scale (TSO version) for social risk; and the CFS for clinical frailty. Caregiver burden (Caregiver Burden Inventory, CBI-15) and family experience measures (PREMs) are assessed contingent upon the presence of a primary caregiver and the provision of their independent informed consent. Satisfaction and process quality are further monitored using study-specific PREMs for patients, caregivers, and interdisciplinary professionals. A Patient Global Impression of Change (PGIC) is collected at the end of the study for patients, caregivers, and professionals to anchor the clinical significance of observed changes. A study-specific social work screening questionnaire is administered to identify patients with unmet social needs who may benefit from social work referral.

Finally, the study includes a pre-planned exploratory analysis to evaluate the equity of the intervention's impact across diverse populations. This analysis will investigate whether sociodemographic determinants-primarily socioeconomic status, social risk, ethnicity, language proficiency, and educational level, as well as the geographical distance to the hospital and the gender of both the patient and the primary caregiver-act as moderators of the intervention effect. The objective is to determine if the coordinated circuit effectively mitigates traditional barriers to care and provides equitable benefits regardless of the patient's or caregiver's sociodemographic profile, among other factors.

The design of this protocol was developed with active input from a patient focus group and the collaboration of the 'AIRE' association to ensure the outcomes reflect the real-world needs of the ILD community.

Interventions

• Other Standard ILD Diagnostic Pathway
  Organizational usual-care comparator following the standard ILD diagnostic workflow. After referral for suspected ILD, core diagnostic procedures such as high-resolution chest computed tomography, complete pulmonary function tests (spirometry and diffusing capacity), six-minute walk test, and a comprehensive ILD laboratory panel are ordered and scheduled independently according to routine departmental workflows and waiting times. Additional procedures, including bronchoscopy with bronchoalveolar
• Other Optimized ILD Diagnostic Circuit
  Organizational intervention that coordinates and bundles core ILD diagnostic procedures into a compressed and structured workflow. For patients with suspected ILD, high-resolution chest computed tomography, complete pulmonary function tests (spirometry and diffusing capacity), the six-minute walk test, and a comprehensive ILD laboratory panel are pre-bundled and scheduled within a shortened timeframe, ideally within one or two coordinated visits. When required, bronchoscopy and rheumatology/inte

Primary outcome measures

• Time to Diagnostic Communication [Time frame: From randomization until the date of diagnostic communication to the patient (up to 18 months).]

Secondary outcome measures (12)

• Time to Multidisciplinary Team (MDT) Diagnosis [Time frame: From randomization until the date of the MDT diagnostic consensus (up to 18 months).]
• Time to Treatment Initiation [Time frame: From randomization until treatment initiation, if required (up to 18 months).]
• Diagnostic Time Burden [Time frame: From randomization until the ILD diagnosis or treatment initiation, if required (up to 18 months).]
• Patient and Caregiver Socioeconomic Cost-Burden [Time frame: From randomization until the ILD diagnosis or treatment initiation, if required (up to 18 months).]
• Hospital Direct and Operational Costs [Time frame: From randomization until the ILD diagnosis or treatment initiation, if required (up to 18 months).]
• Carbon Footprint of the ILD Diagnostic Pathway [Time frame: From randomization until the ILD diagnosis or treatment initiation, if required (up to 18 months).]
• EQ-5D-5L Health-Related Quality of Life Questionnaire [Time frame: Baseline (at the first in-person visit) and at the diagnostic communication visit (up to 18 months)]
• King's Brief Interstitial Lung Disease (K-BILD) Questionnaire [Time frame: Baseline (at the first in-person visit) and at the diagnostic communication visit (up to 18 months)]
• Generalized Anxiety Disorder 7-item Scale (GAD-7) [Time frame: Baseline (at the first in-person visit) and at the diagnostic communication visit (up to 18 months)]
• Patient Health Questionnaire-9 (PHQ-9) [Time frame: Baseline (at the first in-person visit) and at the diagnostic communication visit (up to 18 months)]
• Clinical Frailty Scale (CFS) [Time frame: Baseline (at the first in-person visit) and at the diagnostic communication visit (up to 18 months)]
• Social-Familial Evaluation Scale (TSO version) [Time frame: Baseline (at the first in-person visit) and at the diagnostic communication visit (up to 18 months)]

Eligibility criteria

Inclusion criteria

• Age 18 years or older.
• Referral for suspected or undiagnosed interstitial lung disease (ILD).
• At least one of the following:

• A finding suggestive of ILD (such as reticulation, ground-glass opacities, traction bronchiectasis or honeycombing) not attributable to another disease, on a CT available at referral that includes the lung parenchyma, regardless of its indication; or
• Persistent or progressive shortness of breath or chronic cough not attributable to another disease, accompanied by at least one of the following: an interstitial or reticular pattern on chest radiograph; reduced forced vital capacity; persistent bibasilar crackles or digital clubbing; a relevant environmental or occupational exposure, autoimmune disease, or suspected drug or radiation toxicity; or a first-degree family history of ILD.
• Ability to provide informed consent.

Exclusion criteria

• Complete ILD diagnostic work-up already performed (chest CT plus full pulmonary function testing including six-minute walk test plus complete ILD laboratory panel).
• Established diagnosis of ILD previously assigned by another center or specialist.
• Clinical instability or acute illness that would prevent reliable completion of diagnostic procedures (e.g., respiratory infection, suspected acute ILD exacerbation, acute heart failure).
• Acute iatrogenic pneumonitis (drug-, chemotherapy- or radiation-induced) with a clear temporal relationship to the offending agent.
• Medical, functional, psychiatric or logistical limitations that, in the investigators' opinion, would interfere with the diagnostic process or data collection.
• Participation in another interventional clinical trial that may alter the frequency or timing of diagnostic procedures.
• Cognitive impairment that prevents informed consent or completion of study questionnaires.
• Refusal to participate or to allow the collection or use of clinical data.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Health services research

Study locations

Spain · 1 center

• Hospital General de Granollers — Granollers

Identifiers

NCT: NCT07482917 · OPTIMIZE-ILD-1-HGG

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗