Only a minority of patients with interstitial lung disease (ILD) swiftly receive a correct diagnosis, while more than half are misdiagnosed at least once, finds a Pulmonary Fibrosis Foundation (PFF) survey of 600 ILD patients.
Meanwhile, patients go through invasive and costly diagnostic procedures — often without the desired result.
The findings point up the need for more physician education as well as clinical practice recommendations and better diagnostic tools.
“Our results show that the typical diagnostic experience for patients with ILD, including IPF [idiopathic pulmonary fibrosis], is characterized by considerable delays, frequent misdiagnosis, exposure to costly and invasive diagnostic procedures and substantial use of healthcare resources,” Gregory P. Cosgrove, associate professor of medicine at Denver’s National Jewish Health and the PFF’s chief medical officer, said in a press release.
The study, “Barriers to timely diagnosis of interstitial lung disease in the real world: the INTENSITY survey,” appeared in the journal BMC Pulmonary Medicine.
A delay in diagnosing ILD, of which IPF is the most common and severe form, worsens patient outcomes, said researchers. Current treatment for IPF — Genentech’s Esbriet (pirfenidone) and Boehringer Ingelheim’s Ofev (nintedanib) — can only slow lung function decline without reversing present damage. Their use, therefore, provides most benefits in early disease stages.
Researchers don’t understand what a typical diagnostic journey looks like for people with IPF and similar lung diseases. This is why the PFF launched its INTENSITY study. Nearly half the 600 patients surveyed had IPF; the next largest group had ILD, followed by non-specific interstitial pneumonia, hypersensitivity pneumonitis and sarcoidosis.
Most patients experienced a gradual symptom development, with shortness of breath, cough and fatigue the most common signs that something was wrong. It took people a median of three months to visit a doctor, and 72 percent believed their symptoms were only caused by aging.
Nearly one-third of survey participants saw a primary-care physician four or more times before being referred to a specialist, while 27.8 percent received such a referral after their first visit.
The journey to a correct diagnosis commonly contained wrongful diagnoses — 55 percent had been misdiagnosed at least once, and 38 percent at least twice. The most common misdiagnoses were asthma, pneumonia and bronchitis. For half of the misdiagnosed patients, it took at least an additional 11 months to receive a correct diagnosis. For 34 percent, it took more than two years.
In the entire group, the median time to diagnosis was, however, quicker — seven months. But a median poorly captures the large variations. For 43 percent of patients, it took more than a year to receive a correct diagnosis, and nearly 20 percent had to wait for at least three years.
The road to a diagnosis involved numerous tests. On average, patients had six lung function tests, five chest X-rays, and two bronchoscopies before ending up with a correct diagnosis. In addition, 61 percent also reported undergoing an invasive diagnostic test, including a lung tissue biopsy, while 68 percent of patients said consulting an ILD specialist was the most important contributing factor to obtaining a correct diagnosis.
Not surprisingly, the long and complex diagnostic journey took a toll on quality of life. Many patients said they felt the need to retire or seek disability benefits just to keep up with doctor’s appointments. Appointments were also typically perceived as stressful — 80 percent said it took a negative emotional toll — and took time away from family and friends.
While the survey may have its limitations — for instance, patients with a good diagnostic experience may be less likely to participate — it points up the need for systematic improvements in the diagnostic process.
“The publication of these findings underscores the tremendous need for patients with suspected IPF to get clearer answers faster so that they can receive the treatment they need and avoid potentially harmful diagnostic procedures and treatment,” said Bonnie Anderson, the chairman and CEO of Veracyte. “It also reinforces our commitment to using cutting-edge, machine learning-based genomic technology to answer challenging diagnostic questions and improve patient care.”
Veracyte developed the Envisia Genomic Classifier, a tool to help physicians differentiate IPF from other ILDs without the need for invasive and potentially risky surgery.