Perceptions of Genetic Testing: A Mixed-methods Study of Patients with Pulmonary Fibrosis and their First-degree Relatives

Genetic testing is an emerging tool in interstitial lung disease (ILD) as several ILD subtypes have potential genetic causes or predispositions with resultant clinical implications. There is a need to understand patients' and their first-degree relatives' perceptions of genetic testing for ILD. The objective of this study was to investigate patients with ILD and their first-degree family members' understanding about the genetic risks associated with ILD and their interest and/or concerns about genetic testing. This mixed-methods study included patients with ILD and their first-degree relatives. Data were obtained from an online survey and three focus groups. Categorical data were reported with descriptive frequencies. Chi-squared analyses were used to measure associations. Focus group discussions were transcribed, coded and analysed according to the grounded theory principle. A total of 188 respondents completed the survey; 119 patients, 52 first-degree relatives and 17 who were both patients and who also reported being a first-degree relative to someone with ILD. Most (79%) patients had idiopathic pulmonary fibrosis. The majority of patients and first-degree relatives were unsure if there was a genetic cause, whereas 71% of those who were both patient and first-degree relative thought there could be a genetic cause to their ILD. 59% of respondents worried their family members could be affected, and 72% of respondents were interested in genetic testing. Interest in genetic testing was associated with sex (p=0.03), post-secondary education (p=0.047), and having a family member with ILD (p=0.02). The main motivators were understanding family members' risk and contributing to research. First-degree relatives were concerned about insurance issues (60%) and personal stress (60%) more often than patients (40% and 28%, respectively); 29% of first-degree relatives anticipated changing their health behaviour based on results. Focus group themes included disease knowledge, understanding the role of genetics in ILD, testing concerns, and how to use genetic testing information. This study provides insight into patients' and first-degree relatives' perceptions of ILD-related genetic testing. These findings inform the need for additional patient resources, yet better understanding of the clinical applications of ILD genetic testing, and how testing may impact diagnostics, therapeutics and prognostication.