Vascular volume changes in radiological patterns of usual interstitial pneumonia in patients with type 2 diabetes.

Objective: This research primarily focuses on exploring the changes in intrapulmonary vascular volume (IPVV) in radiological patterns of usual interstitial pneumonia (UIP) associated with Type 2 Diabetes Mellitus (T2DM), thereby inferring the possible mechanisms of the co-occurrence of diabetes and UIP patterns.

Methods: Thin-layer data were post-processed on the basis of high-resolution computed tomography (HRCT) and quantitatively assessed for IPVV. Changes in IPVV were compared between T2DM combined with UIP modality and T2DM non-UIP modality. Correlations between UIP patterns and various markers and confounders, including IPVV, were determined via logistic regression analysis. In this study, the potential of IPVV as a predictor for UIP presence was analysed through the application of subject operating characteristic curve analysis.

Results: In patients with T2DM, the IPVV demonstrated smaller size in those with combined UIP patterns compared to T2DM patients without UIP patterns (164.4 ± 68.7 vs 202.9 ± 76.3 mL, P = 0.005). We detected a positive correlation between IPVV levels and several variables, including fasting plasma glucose (FPG) (r = 0.404, P < 0.0001), glycated hemoglobin (HbA1c) (r = 0.225, P = 0.022), serum uric acid (SUA) (r = 0.332, P = 0.0007) and HRCT scores (r = 0.288, P = 0.024). Conversely, negative correlations were noted with total cholesterol (TC) (r = -0.220, P = 0.028) and cystatin-C (Cys-C) (r = -0.215, P = 0.038). Multivariate logistic regression analysis identified independent associations between the presence of UIP and several factors: IPVV, age, smoking history, and FPG. In assessing the combined UIP pattern among T2DM patients, IPVV levels exhibited a sensitivity of 70.5% and a specificity of 58.5%, generating an AUC of 0.645.

Conclusion: In individuals diagnosed with T2DM alongside UIP, a substantial decline in IPVV was documented. This diminution correlates with the presence of UIP, suggesting that IPVV may serve as a potent biomarker for detecting UIP patterns in individuals with T2DM. This may suggest that the mechanism behind the co-occurrence of T2DM with UIP patterns is attributed to alterations in the pulmonary microvasculature, potentially representing one of the vascular complications associated with diabetes.