IPF Diagnosis and Treatment Changing for Better in UK, Registry Study Finds
Changes for the better in diagnosing idiopathic pulmonary fibrosis (IPF) and managing patients in the U.K. are evident in recent years, a real-world study based on registry data indicates.
“Patient registries offer a unique opportunity to collect longitudinal data on uncommon diseases, such as IPF,” the researchers wrote. “Over the 6 years since it was established, the UK IPF Registry has collected baseline clinical data on over 2400 patients, which is the largest single-country IPF registry reported to date.”
And, unlike in “clinical trials, which exclude patients based upon lung function impairment, comorbidities and concurrent medications, this retrospective analysis provides a more ‘real world’ overview of patients with IPF in the UK,” they added
The study, “Idiopathic pulmonary fibrosis in the UK: analysis of the British Thoracic Society electronic registry between 2013 and 2019,” was published in the journal ERJ Open Research.
IPF is a progressive lung disease of unknown cause characterized by the thickening and stiffening of lung tissue, leading to scarring (fibrosis) that gradually compromises a person’s ability to breathe.
Although a significant increase in IPF cases has been reported worldwide, a need for real-world data concerning disease incidence and prevalence exists, so that patients may receive appropriate clinical care.
Researchers with the British Thoracic Society and colleagues analyzed data from 2,474 IPF patients, stored at the U.K. IPF registry between Jan. 1, 2013 (when it began collecting data) and Oct. 31, 2019, to evaluate patient characteristics, and the diagnostic and treatment approaches used in a real-world setting.
Most patients were male (79%), with a mean age of 74. More than half (66%) were ex-smokers, and 5% had at least one close relative with IPF. Notably, there was a significant increase in the number of patients older than age 70 (59% in 2013 to 80% in 2019).
One or more additional health conditions (comorbidities) were reported in more than 80% of these patients. The most common were high blood pressure (34%), heart disease (21%), diabetes mellitus (type 1 diabetes, 20%), and gastric reflux (18%). Chronic obstructive pulmonary disease (COPD) was seen in 6% of the patients.
Most patients (66%) had trouble breathing or cough for over a year. In total, 9% experienced symptoms for less than six months, and 40% for more than two years. No significant change was seen in the proportion of patients presenting early disease symptoms during the study.
Researchers also analyzed patients’ lung function using two different parameters: forced vital capacity (FVC), which measures the total amount of air a person is able to exhale after a deep breath; and the diffusing capacity of the lung for carbon monoxide (DLCO or TLCO), which measures how much oxygen is transferred from the lungs to the bloodstream.
At disease onset, patients’ mean predicted FVC and TLCO was 78.2% and 48.4%, respectively. There was little change in FVC and a trend toward lower TLCO over time, although it was not significant.
At the time of registry enrollment, the distribution of GAP (gender, age, and physiology) scores — a tool for estimating disease outcomes, specifically one- to three-year mortality risk — had 35% of patients at stage 1 (lower risk), 55% at stage 2 (moderate risk) and 10% at stage 3 (higher risk). Over time, the percentage of patients in stage 1 fell from 45% to 30%, while those at stage 2 rose from 48% to 64%.
Most patients (69%) had oxygen blood saturation levels, measured by pulse oximetry, over 95%. The remaining patients had levels ranging between 88% and 94% (28%) or lower than 88% (3%).
Although 74% of patients felt they were able to perform the six-minute walk test (6MWT), a measure of physical endurance, only about a third (638 of 1,812 people) completed it. Of those who did, 327 walked more than 300 meters within six minutes, and 147 walked less than 150 meters in that time.
A majority of IPF cases (89%) were discussed with an interstitial lung disease (ILD) multidisciplinary team. Based on high-resolution computed tomography (HRCT) scans, 44% of the patients were diagnosed as having usual interstitial pneumonia (UIP, a progressive ILD condition), and 50% with possible UIP. HRCT findings were inconsistent with UIP in 4% of the cases.
A non-significant decrease was seen over time in the percentage of patients undergoing surgical lung biopsy (16% to 3%) and bronchoalveolar lavage (12% to 4%) — a procedure in which a fluid is squirted into a small portion of the lung and then aspirated to be analyzed.
Of 57% of eligible patients, 44% were using an anti-fibrotic therapy. An increase in the use of these treatments was seen over time, particularly Ofev (nintedanib), but the rise was not significant.
Moreover, 3% (53 out of 1,809) of patients were referred for lung transplant, and 63% were considered unsuitable candidates. Of those referred, seven received a transplant either initially or during follow-up.
Regarding supportive therapies, 21% of the patients were given oxygen therapy, and referrals for pulmonary rehabilitation rose from 55% in 2013 to 84% in 2019, but it was not significant.
Patients’ median survival was a little over a year (496.5 days) and the mortality rate was 10% over the study’s years. IPF progression or exacerbation accounted for 55% of these deaths. Lung cancer, diagnosed in 1% of IPF patients, was associated with a worse prognosis and accounted for 3% of deaths.
Limitations to their study’s findings, the researchers noted, largely concerned incomplete datasets .
These findings show “key changes in the diagnostic evaluation of patients with suspected IPF in the UK between 2013 and 2019 suggesting a better understanding of the clinical and radiological predictors of IPF,” the researchers wrote.
“We have also observed vital improvements in patient care,” they added. “How these changes will impact longer-term outcomes such as hospitalisation and survival, as well as informing development of healthcare policies, remains to be determined.”