Elevated Suicide Risk in Idiopathic Pulmonary Fibrosis Patients

To the Editor:

The study, “Risk of Suicide in Individuals with Idiopathic Pulmonary Fibrosis: A Nationwide Cohort Study,” by Kim and coworkers reveals an increase in the risk of suicide in patients with a diagnosis of idiopathic pulmonary fibrosis (IPF) (1). Such findings are important to clinical practices and the public health arena, thereby drawing attention to the psychological burden related to the disease and calling for more targeted mental health interventions.

However, several potential limitations and ways to improve the strength and validity of the study are in place. First, the use of International Classification of Diseases, 10th Revision codes in determining an IPF diagnosis and also other comorbidities sets up the study for misclassification bias, which is common in real-world studies (2, 3). International Classification of Diseases, 10th Revision codes are very reliable, but, at times, do not capture the dynamic nature of IPF or the diseases with which it is associated in many cases. Future studies should include clinical data such as high-resolution computed tomography scans and pulmonary function tests to confirm the diagnoses of IPF and gather a more detailed understanding of patient conditions.

Second, although the authors controlled for a variety of possible confounders, the study did not control for specific treatments of IPF, including antifibrotic agents (pirfenidone and nintedanib). These medications modify the natural history of the disease and may also modify the quality of life of patients; because they are so influential, they may also exert a psychological impact on the patient. It would have been interesting to consider treatment variables at this moment in the analysis to give more depth to the associations between the management of IPF and suicide risk. For example, antifibrotic treatments decrease mortality as well as acute exacerbations in patients with IPF, which might alleviate some psychological distress due to the prognosis of IPF (4).

The study also did not assess how social support systems might influence suicide risks among patients with IPF. Social support through family involvement, community activity, and access to mental health services functions as suicide prevention within an at-risk environment of chronic disease management. Further studies should investigate the role of social support in this population in terms of reducing suicide risk. For instance, some studies suggest that substantial emotional and practical social support networks significantly decrease the propensity for suicide among patients with a chronic disease (5).

In addition, the demographic and geographical characteristics may not be generalizable to the overall population. The dataset was collected based on the Korean population, which might not represent other ethnic and cultural groups. This will certainly require that studies be conducted in diverse populations to highlight the availability of these factors across demographic groups. Cross-cultural research will uncover further risk factors and measures of protection that would be unique to various populations, therefore making the findings more applicable globally.