Risk factors for diagnostic delay in idiopathic pulmonary fibrosis

Abstract

Background Surveys and retrospective studies of patients with idiopathic pulmonary fibrosis (IPF) have shown a significant diagnostic delay. However, the causes and risk factors for this delay are not known. Methods Dates at six time points before the IPF diagnosis (onset of symptoms, first contact to a general practitioner, first hospital contact, referral to an interstitial lung disease (ILD) centre, first visit at an ILD centre, and final diagnosis) were recorded in a multicentre cohort of 204 incident IPF patients. Based on these dates, the delay was divided into specific patient-related and healthcare-related delays. Demographic and clinical data were used to determine risk factors for a prolonged delay, using multivariate negative binomial regression analysis. Results The median diagnostic delay was 2.1 years (IQR: 0.9–5.0), mainly attributable to the patients, general practitioners and community hospitals. Male sex was a risk factor for patient delay (IRR: 3.84, 95% CI: 1.17–11.36, p = 0.006) and old age was a risk factor for healthcare delay (IRR: 1.03, 95% CI: 1.01–1.06, p = 0.004). The total delay was prolonged in previous users of inhalation therapy (IRR: 1.99, 95% CI: 1.40–2.88, p < 0.0001) but not in patients with airway obstruction. Misdiagnosis of respiratory symptoms was reported by 41% of all patients. Conclusion Despite increased awareness of IPF, the diagnostic delay is still 2.1 years. Male sex, older age and treatment attempts for alternative diagnoses are risk factors for a delayed diagnosis of IPF. Efforts to reduce the diagnostic delay should focus on these risk factors. Trial registration This study was registered at http://clinicaltrials.gov (NCT02772549) on May 10, 2016. Electronic supplementary material The online version of this article (10.1186/s12931-019-1076-0) contains supplementary material, which is available to authorized users.

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

“…Finally, because of our study design, we could only assess factors influencing diagnostic delays within our health systems, both of which are academic medical centers with a large external referral population relative to internal referrals. Whether these results are generalizable to cohorts drawn from community centers remains unclear; however, the consistencies of our findings with those of others who have included patients from community centers do suggest some degree of generalizability [5][6][7].…”

“…While our study focused on factors influencing diagnostic delays within two academic institutions, Hoyer Table 4 Time from documented ILD clinical feature to chest CT and pulmonology referral and colleagues recently provided a more global assessment of diagnostic delays in patients with ILD using national health data in Denmark [7]. Similar primary carerelated delays were observed, but significant delays related to patient factors and within the community pulmonologist setting were also identified.…”

“…A recent investigation by Hoyer and colleagues showed that ILD diagnostic delays occur in several settings, with the primary care setting playing a prominent role [7]. Factors leading to ILD diagnostic delays remain unclear, but may stem from unrecognized or underappreciated features of ILD on diagnostic testing.…”

“…Studies to date characterizing diagnostic delays in patients with ILD have largely relied on patient questionnaires and insurance claims data [4][5][6][7]. While informative, these studies do not assess physician-level factors that may influence such delays.…”

Diagnostic precision and identification of rare diseases is dependent on distance of residence relative to tertiary medical facilities

“…In idiopathic pulmonary brosis early treatment can slow down disease progression and therefore the decline in lung function (22). Those low prevalent diseases with nonspeci c symptoms as interstitial lung diseases (cough, dyspnea) are explicitly in danger to have a diagnostic delay (3,23). In Glucose transporter-1 de ciency syndrome ketogenic diet reduces the frequency of seizures and severity of motoric impairment (24).…”