A self-reported family history of pulmonary fibrosis (PF) is predictive of decreased transplant-free survival in patients with idiopathic PF (IPF) and in those with non-IPF interstitial lung disease (ILD). Researchers conducted a retrospective investigation at the University of Texas-Southwestern (UTSW) in Dallas, Texas, and at the University of California at Davis (UCD) in Sacramento, California. Results of the study were published in the journal CHEST.
Recognizing that several genetic markers linked to familial PF predict differential survival in patients with ILD, the researchers sought to examine whether survival varies among patients with and without self-reported PF. Family history was obtained systematically for consecutive patients with ILD who consented to clinical registry enrollment at UTSW and UCD. All patients were stratified based on IPF and non-IPF diagnoses, and were further stratified based on the presence or absence of familial PF (defined as ≥1 additional affected family members).
A total of 1262 individuals were included in the study, 534 of whom had a diagnosis of IPF and 728 of whom had a diagnosis of non-IPF ILD, including 234 patients with connective tissue disease (CTD)-ILD, 197 with chronic hypersensitivity pneumonitis, and 297 with unclassifiable ILD (uILD). Familial PF was reported in 134 patients with IPF and in 90 individuals with non-IPF ILD. The mean participant age ranged from 57 to 68 years. Patients with IPF were mainly men and patients with CTD-ILD were mainly women, while those with uILD had sex ratios that were nearly equal. Approximately half of all participants reported a prior smoking history.
Transplant-free survival (TFS) was the best among patients with sporadic non-IPF ILD and the worst among those with familial IPF. In addition, TFS was similar among patients with sporadic IPF and those with familial non-IPF ILD. Participants with familial IPF had a 40% increased risk for death or lung transplantation compared with patients with sporadic IPF, which increased to 80% after multivariable adjustment (hazard ratio [HR], 1.8; 95% CI, 1.37-2.37; P <.001).
Among participants with familial non-IPF ILD, the outcome risk was almost 80% higher compared with those with sporadic non-IPF ILD, increasing to more than 2-fold following multivariable adjustment (HR, 2.08; 95% CI, 1.46-2.96; P <.001). The outcome risk among participants with familial non-IPF ILD, however, did not differ from that among those with sporadic IPF (HR, 1.27; 95% CI, 0.89 to 1.84; P =.19).
The investigators concluded that because survival among individuals with familial IPF ILD approximates that among those with sporadic IPF, early intervention should be considered for such patients. Until clinical genetic testing becomes more widely available, family history needs to be ascertained and taken into account in risk stratification.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Cutting C, Bowman WS, Dao N, et al. Family history of pulmonary fibrosis predicts worse survival in patients with interstitial lung disease. CHEST. Published online January 20, 2021. doi:10.1016/j.chest.2021.01.026