Fibrotic interstitial lung diseases (fILDs) are a group of conditions that cause scarring in the lungs and have a high morbidity and mortality rate. There is a scarcity of research on how socioeconomic and residential characteristics affect people with fILDs. In patients with fILD from the United States (US) and Canada, the researchers wanted to see a link between neighborhood deprivation and presentation severity, illness progression, lung transplant, and mortality. In a multicenter, international prospective cohort research, 4,729 patients with fILD from one US and eight Canadian ILD registry sites. The area deprivation index (ADI) in the United States and the Canadian Index of Multiple Deprivation (CIMD) in Canada assessed neighborhood disadvantage. Patients with fILD living in the most disadvantaged neighborhoods (top quartile) have the highest mortality risk (hazard ratio=1.51, p=0.002). In subgroups of patients with idiopathic pulmonary fibrosis (IPF), the top quartile of disadvantage has the lowest odds of lung transplant (odds ratio=0.46, p=0.04) in the US, but not in the Canadian cohort.
In both cohorts, the greater disadvantage was linked to a lower baseline carbon monoxide diffusion capacity (DLCO) but not to a lower baseline forced vital capacity (FVC) or deterioration in FVC or DLCO. Patients with fILD who live in places in the United States with greater neighborhood-level disadvantage have a higher mortality rate, and patients with IPF have a decreased chance of receiving a lung transplant. These discrepancies are not evident in Canadian patients, indicating that healthcare access in the United States and Canada differs.