Plasma heat shock protein 90α shows a concentration-dependent, threshold association with pulmonary nodules in asymptomatic males >40 years undergoing low-dose computed tomography.

ObjectiveHeat shock protein 90α is involved in tumorigenesis; however, its concentration-dependent relationship and threshold with pulmonary nodules remain unclear. This study aimed to explore the association and critical threshold of plasma heat shock protein 90α levels with the prevalence of pulmonary nodules in males aged ≥40 years.MethodsThis study included 968 male participants (aged ≥40 years) undergoing low-dose computed tomography and plasma heat shock protein 90α measurement from January 2022 to June 2024. Restricted cubic splines and segmented logistic regression were used to identify were the inflection point of the concentration-response relationship. Multivariable models were adjusted for age, smoking index, high-density lipoprotein cholesterol, triglycerides, and family history of lung cancer.ResultsPulmonary nodules were detected in 40.2% (389/968) of participants. The prevalence of pulmonary nodules increased from 28.7% to 51.0% across heat shock protein 90α quartiles (P for trend <0.001). A threshold was identified at 89.5 ng/mL (95% confidence interval: 87.2-93.1). Above this level, each 1 ng/mL increase in the heat shock protein 90α levels was associated with a 3% higher prevalence of pulmonary nodules (adjusted odds ratio = 1.03, 95% confidence interval: 1.01-1.05). The adjusted odds ratio for the highest versus lowest quartile was 1.88 (95% confidence interval: 1.26-2.80).ConclusionsElevated plasma heat shock protein 90α levels are associated with an increased prevalence of pulmonary nodules in asymptomatic males aged ≥40 years, with a critical threshold of 89.5 ng/mL.