Delayed IPF Diagnoses Linked to Heart, Gastro-esophageal Conditions

Conditions affecting the heart, stomach, and esophagus occur more frequently in patients whose diagnosis of idiopathic pulmonary fibrosis (IPF) is delayed, coming more than one year after the onset of symptoms, according to a recent study.

This delayed diagnosis seems, however, to have no impact on the risk of death or the need for a lung transplant, the researchers noted.

The study, “Time to diagnosis of idiopathic pulmonary fibrosis in the IPF-PRO Registry,” was published in the journal BMJ Open Respiratory Research.

The length of time between the onset of symptoms and a diagnosis of IPF varies, especially because the respiratory system disease is often not immediately recognized. A prompt diagnosis enables the early initiation of treatment, which can slow the progression of IPF and provide needed supportive care.  Such care can include referrals to pulmonary rehabilitation or for lung transplant, and the treatment of comorbidities, or other medical conditions, including gastro-esophageal reflux disease (GERD).

To better understand what drives diagnostic delays — and what risks a delayed diagnosis might carry — researchers from across the U.S. reviewed patient records from the Idiopathic Pulmonary Fibrosis Prospective Outcomes (IPF-PRO) Registry (NCT01915511). This ongoing observational registry of  people in the U.S. with IPF seeks to improve understanding of the clinical course of IPF, its impact on patients, and practices in diagnosis and care.

The team identified 347 people with a recorded date of symptom onset, and 454 individuals with a recorded date for having imaging evidence of fibrosis. In total, 303 patients had usable dates for both parameters.

Among those with a symptom onset date, 49% were only diagnosed with IPF more than one year after their symptoms first appeared. Almost a quarter of these patients (23.7%) received their diagnosis after more than three years. The median time from symptom onset to diagnosis in this group was 13.6 months.

For those with imaging evidence, the median time to diagnosis was much shorter — 3.5 months. Although some of these patients experienced delays of between one and three years before being diagnosed with IPF, most of them (78%) received their diagnosis within one year of having imaging-based evidence of pulmonary fibrosis.

Overall, people who experienced longer periods of time between symptom onset and diagnosis tended to be slightly younger, with a median age of 67 versus age 69 in those diagnosed within one year of symptoms. No other significant differences, such as in sex, history of smoking, or relevant family history of lung diseases, were found between the two groups.

The most common symptoms reported at onset were shortness of breath, cough, fatigue, and weight loss.

The appearance of certain conditions alongside the symptoms of IPF — known as comorbidities — differed between patients depending on how long they went between symptom onset and diagnosis.

Those patients with a shorter time to diagnosis were more likely to have chronic kidney disease. Meanwhile, those with a longer period before diagnosis were more likely to experience GERD, obstructive sleep apnea, coronary artery disease, and cardiac abnormalities, including atrial fibrillation, atrial flutter, deep vein thrombosis, and pulmonary embolism.

Certain comorbidities, particularly those involving the heart, can have many of the same symptoms as IPF, the team noted. The researchers said that raised the possibility of delayed diagnoses and even misdiagnoses.

Overall, the results show that despite improved awareness of the disease, “the time from symptom onset to diagnosis remains over 1 year in about half of the patients.”

“But once imaging evidence of pulmonary fibrosis  is obtained, most of the patients are diagnosed within a year,” the researchers wrote.

The team emphasized that “certain comorbidities are associated with a longer time to diagnosis,” including “cardiac conditions and gastro-oesophageal disorders.”