Re-evaluation of diagnostic parameters is crucial for obtaining accurate data on idiopathic pulmonary fibrosis

Abstract

BackgroundThe FinnishIPF registry is a prospective, longitudinal national registry study on the epidemiology of idiopathic pulmonary fibrosis (IPF). It was designed to describe the characteristics, management and prognosis of prevalent and incident IPF patients. The study was initiated in 2012.MethodsWe present here results limited to five university hospitals. Patients with IPF were screened from hospital registries using ICD-10 diagnosis codes J84.1 and J84.9. All patients who gave informed consent were included and evaluated using novel diagnostic criteria. Point prevalence on the 31st of December in 2012 was calculated using the reported population in each university hospital city as the denominator.ResultsPatients with ICD-10 codes J84.1 and J84.9 yielded a heterogeneous group – on the basis of patient records assessed by pulmonologists only 20–30 % of the cases were IPF. After clinical, radiological and histological re-evaluation 111 of 123 (90 %) of patients fulfilled the clinical criteria of IPF. The estimated prevalence of IPF was 8.6 cases/100 000. 60.4 % were men. Forty four percent of the patients were never-smokers. At diagnosis, the patients’ mean age was 73.5 years and mean FVC was 80.4 % and DLCO 57.3 % of predicted.ConclusionsOur results suggest that hospital registries are inaccurate for epidemiological studies unless patients are carefully re-evaluated. IPF is diagnosed in Finland at a stage when lung function is still quite well preserved. Smoking in patients with IPF was less common than in previous reports.

Co‐morbidity and mortality among patients with interstitial lung diseases: A population‐based study

“…Therefore, we chose not to include specific ICD‐10 codes for ILD subtypes. The same conclusion about the validity of ILD subtype diagnoses was reached in a recent study from Finland . Although ILD are a diverse group of disorders, similarities in disease patterns and prognostic factors exist across ILD subtypes.…”

“…The same conclusion about the validity of ILD subtype diagnoses was reached in a recent study from Finland. 40 Although ILD are a diverse group of disorders, similarities in disease patterns and prognostic factors exist across ILD subtypes. As an example, the ILD-gender age physiology (GAP) accurately predicts mortality in major chronic ILD subtypes at all stages of disease.…”

Are physicians in primary health care able to recognize pulmonary fibrosis?

“…[18,19] The subjects had been originally referred to tertiary care due to respiratory problems, and they had been examined in one of the following University hospitals in Finland: Helsinki, Kuopio, Oulu or Turku. A structural data acquisition form was utilized in data collection.…”

Forced Vital Capacity (FVC) decline, mortality and healthcare resource utilization in idiopathic pulmonary fibrosis

“…IPF prevalence estimates vary from 2-29 cases/100 000 persons, with 8.6-19 cases/100 000 persons in Finland [1,8,9]. Differing study designs and historically ununiform definitions likely explain the variability in prevalence.…”

“…Differing study designs and historically ununiform definitions likely explain the variability in prevalence. In Finland, IPF and other ILD are diagnosed under ICD-10 code J84.1, leading to challenges in distinguishing between the diseases in retrospective studies, however, estimates are that 20-30% of these patients have IPF [9,10].…”