Clinical features and related factors of combined pulmonary interstitial fibrosis and emphysema syndrome in the elderly / 中华老年医学杂志

ABSTRACT

Objective:To summarize the clinical characteristics and risk factors of combined pulmonary fibrosis and emphysema syndrome(CPFE)in the elderly.Methods:42 patients with CPFE and 83 patients with idiopathic pulmonary fibrosis(IPF)admitted to Beijing Hospital from January 2015 to January 2020 were included for this retrospective study, and their clinical data, laboratory test results, imaging, pulmonary function and treatment outcomes were compared.The correlations of diffusing capacity of the lungs for carbon monoxide(DLCO)with lung volume and other ventilation-related parameters were analyzed.Multivariate Logistic analysis was used to screen for risk factors.Results:Compared with the IPF group, the proportions of patients who were male(78.6% or 33/42 vs.50.6% or 42/83), were smokers(78.6% or 33/42 vs.45.8% or 38/83)and had allergies(23.8% or 10/42 vs.4.8% or 4/83)were significantly higher in the CPFE group( χ2=9.090, 12.219, 8.293, P=0.003, 0.000, 0.004, respectively). Eosinophil counts were significantly higher in the CPFE group than in the other group[0.17×10 9/L with a(0.12-0.25)×10 9/L range vs.0.10×10 9/L with a(0.03-0.21)×10 9/L range]. In terms of pulmonary function tests, patients with CPFE had higher levels of vital capacity(VC)[2.60 L, range (2.18-3.08)L vs.1.99 L, range (1.48-2.63)L], total lung capacity(TLC)[4.54 L, range (3.89-5.45)L vs.3.74 L, range (2.92-4.70)L], forced vital capacity(FVC)[2.46 L, range (2.12-3.08)L vs.1.95 L, range (1.43-2.58)L], and forced expiratory volume in 1 second(FEV1)/FVC%[84.18%, range (75.59-88.83)% vs.80.94%, range (69.07-83.08)%], with significant differences from patients in the IPF group( Z=2.032, 2.248, 2.357, 2.421, 3.102, P=0.042, 0.025, 0.018, 0.015, 0.002). Positive correlations of DLCO were found with residual volume of the predicted(RV%pred), vital capacity of the predicted(VC%pred), alveolar ventilation of the predicted(VA%pred), total lung capacity of the predicted(TLC%pred), forced vital capacity of the predicted(FVC%pred), and percentage of forced expiratory volume in first second as predicted(FEV1%pred)in the IPF group( r=0.422, 0.370, 0.473, 0.520, 0.356, 0.267, P=0.000, 0.002, 0.000, 0.000, 0.003, 0.029), but not in the CPFE group.According to multivariate Logistic regression analysis, smoking( OR=5.421, 95% CI 1.458-20.154, P=0.012)and allergies( OR=7.458, 95% CI 1.795-30.979, P=0.006)were independent predictors of CPFE. Conclusions:The eosinophil count and lung volume in elderly CPFE patients are higher than those in IPF patients, and the significant feature is the decrease of DLCO, which is not correlated with changes in lung ventilation parameters and lung volume.Smoking and allergies are risk factors for CPFE in the elderly.