The diagnostic pathway for patients with interstitial lung disease: a mixed-methods study of patients and physicians.

Objectives: The diagnostic process for patients with interstitial lung diseases (ILD) remains complex. The aim of this study was to characterise the diagnostic care pathway and identify barriers and potential solutions to access a timely and accurate ILD diagnosis.

Design: This mixed-method study was comprised of a quantitative chart review, patient and physician surveys and focus groups.

Results: Chart review was completed for 97 patients. Median time from symptom onset to ILD diagnosis was 12.0 (IQR 20.5) months, with 46% diagnosed within 1 year. Time from first computed tomography (CT) scan to respirology referral was 2.4 (IQR 21.2) months. Referrals with a prior CT were triaged sooner than referrals without (1.7±1.6 months vs 3.9±3.3 months, p=0.013, 95% CI 0.48 to 2.94). On patient surveys (n=70), 51% felt that their lung disease was not recognised early enough. Commonly reported challenges to timely diagnosis included delayed presentation to primary care, initial misdiagnoses and long wait-times for specialists. Forty-five per cent of physicians (n=20) identified diagnostic delays, attributed to delayed presentations to primary care (58%), initial misdiagnoses (67%) and delayed chest imaging (75%). Themes from patient and respirologist focus groups included patient-related, healthcare provider-related and system-related factors leading to delays in diagnosis.

Conclusions: This mixed-methods study identified patient and system-related factors that contribute to diagnostic delays for patients with ILD, with most delays occurring prior to respirology referral. ILD awareness and education, earlier presentation to primary care, expedited access to chest imaging and earlier referral to respirology may expedite diagnosis.