Patient-Reported Outcomes Linked to Mortality in Idiopathic Pulmonary Fibrosis

June 5, 2020
Rachel Lutz
Rachel Lutz

The study sought to determine whether patient-reported outcomes are linked with death beyond clinical risk factors in patients with idiopathic pulmonary fibrosis (IPF).

Patient-reported outcomes regarding symptoms and physical abilities were independently associated with mortality in patients with idiopathic pulmonary fibrosis (IPF), according to a paper published in the Annals of the American Thoracic Society.

Investigators from across the United States tracked the outcomes of 662 patients with IPF in order to assess whether patient-reported outcomes are linked with mortality beyond clinical risk factors in these patients. They identified these patients through the IPF-PRO (IPF Prospective Outcomes) Registry—an ongoing, observational US registry of patients with IPF—and their analysis was open to anyone registered from its start in June 2014 to October 2017. The patients in the report had diagnosed or confirmed with IPF in the last 6 months.

Three-quarters of the patients were male and the median age was 70 years at enrollment, authors said. About 1 in 5 patients was using supplemental oxygen at rest, they added.

The investigators reviewed patient-reported outcomes at enrollment, including cough symptoms (frequency and severity), physical activity such as effects of breathlessness, and impact, such as the psychological impact of the disease and how it effects social functioning. The investigators collected data from deaths at the enrollment center and if patients had not visited, they called every 6 months to confirm vital status, they explained.

Most of the patient-reported outcomes showed a relationship between mortality or lung transplant in the early months but that relationship began to reduce after 10 to 16 months post-enrollment in the IPF-PRO, the study authors said. That’s why they limited their analysis to the first year after enrollment.

The researchers explained that lung transplant was included in the primary outcome because it serves as a marker of disease progression that would otherwise be expected to result in death.

“Given that lung transplantation is generally associated with an improvement in health related quality of life in patients with advanced lung disease, it might also be speculated that worse health related quality of life may increase the risk of the primary outcome, because impaired health related quality of life may play a role in some patients deciding to have a lung transplant,” the authors added.

Within the first year, the investigators observed 45 deaths and 12 lung transplants among the 662 patients. The mean age at transplant was 67 years, though the maximum was 71 years. The investigators found an 86% change of being free from both events after 1 year.

Worse health related quality of life at enrollment was associated with death or lung transplant after 1 year of follow up, the authors said. The investigators found generally consistent outcomes for both patient-reported outcomes and death, respiratory-related death or lung transplant over 1 year and those with death or lung transplant.

After the investigators accounted for age and clinical characteristics of the patients, characteristics associated with death or lung transplant over the course of 1 year of follow up included worse scores on the St. George’s Respiratory Questionnaire (SGRQ) total score, SGRQ activity score, and SGRQ symptoms score, the authors said.

Patients with IPF generally report limitations in their mobility, low levels of energy, and difficulty with basic tasks that require exertion, leading to low SGRQ activity scores; in their findings, low SGRQ scores had the strongest association with death or lung transplant over 1 year compared to all other patient-reported outcomes, the researchers said.

The authors wrote that their findings suggest “that patient-reported outcomes provide important information beyond physiological measures of disease severity, such as lung function.”

“Further analysis of long-term data from the IPF-PRO Registry will investigate the extent to which changes in patient-reported outcomes over time are associated with mortality in patients with IPF,” they concluded.

Reference

Case AH, Hellkamp AS Neely ML, et al. Associations between patient-reported outcomes and death or lung transplant in idiopathic pulmonary fibrosis. Data from the idiopathic pulmonary fibrosis prospective outcomes registry. Ann Am Thorac Soc. 2020;17(6)699-705 . doi: 10.1513/AnnalsATS.201906-437OC