Ethnicity as a Factor Affecting Survival in Pulmonary Fibrosis

Pulmonary fibrosis (PF) is a progressive disease that develops when the lungs become damaged and scarred. The scar tissue that forms in the lungs’ air sacs prevents oxygen from entering the blood.

The causes of pulmonary fibrosis can be numerous and vary from patient to patient. Or they can be unknown, as is the case for people with idiopathic pulmonary fibrosis (IPF). But whether a person’s ethnic group, or ethnicity, plays a role in the disease’s possible progression is an open question, and the focus of a growing body of research trying to determine whether race or ethnic background might affect a patient’s chances of survival.

One reason ethnicity has become a research interest is that, as a rare disease, PF patients only began to be included in U.S. clinical trials in the mid- to late 1990s, and non-Hispanic whites made up the majority of patients until recent years.

Researchers used a National Center for Health Statistics database for a study, published in 2012, that looked at mortality differences among IPF patients in the U.S. by racial and ethnic group. In total, 38.9 million death records dating from 1989 and 2007 were examined, and 251,058 people with IPF whose ethnicity was recorded were identified. An overwhelming majority, 87.2%, were white; followed by Hispanics, 5.4%; non-Hispanic blacks,  5.1%; and those of other racial or ethnic groups,  2.2%, with “others” defined as Asian, Native American or Pacific islanders.

Notably, a significantly higher proportion of IPF was found among those of Hispanic and or “other” ethnicities compared to whites, while that proportion was significantly lower for blacks compared to whites. But blacks and Hispanics IPF patients died on average at younger ages (72.1 years old for blacks and 75.6 years for Hispanics) than whites (77.9 years).

Pulmonary fibrosis was more common among men (53%) than women (47%) overall, although Hispanic women outnumbered men in the death records examined.

The researchers noted, however, that their study lacked information that could be important to a review of ethnicity and pulmonary fibrosis, like health insurance coverage, access to and use of medical care, and risk behaviors like cigarette smoking.

A 2015 study found it “plausible” that “biological differences between ethnic groups result in different susceptibilities to IPF.” This review study, based on published research and abstracts between 2000-14, also confirmed that whites were over-represented in research into IPF (85.3% of patients vs. 77.7% of the U.S. population) while blacks were under-represented (8% of patients vs. 13.2% of population). Because only three of the 44 studies examined included Asians, the researchers reported.

Another study considered ethnical and racial disparities among IPF patients waiting for a lung transplant, and found higher death rates among black and Hispanic PF patients than white patients independently of age, gender, or comorbidities (the presence of one or more additional diseases), insurance status, and socioeconomic status.  According to the researchers, these “disparities in survival were attributable in part to worse lung function among both blacks and Hispanics compared to whites at the time of listing” for a lung transplant. This suggested, they said, that ethnicity could play a crucial role in the pre-referral medical care given patients, the timing of referral and disease phenotype.

Such social differences were also found to extend beyond pulmonary fibrosis. Lung diseases like asthma, cancer, and pulmonary arterial hypertension showed similar racial and ethnic differences, suggesting broad problems in access to quality healthcare. The authors concluded that barriers to medical care for minority patients are a probable cause for the study’s findings.

Note: Pulmonary Fibrosis News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. 

Your PF Community

Woman laying down reading

Visit the Pulmonary Fibrosis News forums to connect with others in the PF community.

View Forums