LAUSR

Background Patient sex has clinical and prognostic implications in idiopathic pulmonary fibrosis (IPF). It is not known if sex-related and gender-related discrepancies exist when establishing a diagnosis of IPF. The aim was to determine how patient gender influences the diagnosis of IPF and the physician’s diagnostic confidence. Methods This study was performed using clinical cases compiled from a single centre, then scored by respiratory physicians for a prior study. Using clinical information, physicians were asked to provide up to five diagnoses, together with their diagnostic confidence. Logistic regression was used to assess the odds of receiving a diagnosis of IPF based on patient gender. Prognostic discrimination between IPF and non-IPF was used to assess diagnostic accuracy with Cox proportional hazards modelling. Results Sixty cases were scored by 404 physicians. IPF was diagnosed more frequently in men compared with women (37.8% vs 10.6%; p<0.0001), and with greater mean diagnostic confidence (p<0.001). The odds of a male patient receiving an IPF diagnosis was greater than that of female patients, after adjusting for confounders (OR=3.05, 95% CI: 2.81 to 3.31), especially if the scan was not definite for the usual interstitial pneumonia pattern. Mortality was higher in women (HR=2.21, 95% CI: 2.02 to 2.41) than in men with an IPF diagnosis (HR=1.26, 95% CI: 1.20 to 1.33), suggesting that men were more often misclassified as having IPF. Conclusion Patient gender influences diagnosis of IPF: women may be underdiagnosed and men overdiagnosed with IPF.