Abstract: Objective  To explore the differences of risk factors between patients with tuberculous pleural effusion and malignant pleural effusion and to provide basis of clinical diagnosis of pleural effusion. Methods  We consecutively enrolled the 264 patients who was diagnosed of tuberculous pleural effusion or malignant pleural effusion in January 2006—December 2012 in respiratory department of the 2nd Affiliated Hospital of Qingdao University, of which 147 cases were tuberculous pleural effusion and 117 cases were malignant pleural effusion. We compared the patients’ age, gender, whether with diabetes, respiratory disease history, the economic status, work tired feeling, group living behavior, lack of exercise, eating regularity, sleep time, psychological stress, smoking index, disease family history between the 2 groups.The univariate and multivariate logistic regression analysis was made on the risk factor for morbidity of tuberculous pleural effusion and malignant pleural effusion.  Results  The univariate results showed that diabetes mellitus［15.0% (22/147) vs 6.8% (8/117), χ²=4.571, P=0.034］, low economic status［38.1% (56/147) vs 29.9% (35/117),χ²=5.103, P=0.028］, with group living behavior［29.3% (43/147) vs 9.4% (11/117),χ²=4.977, P=0.030］, are risk factors for tuberculous pleural effusion; Age >40 years［45.6% (67/147) vs 78.6% (92/117),χ²=4.752, P=0.032］, high degree of psychological stress［15.0% (22/147) vs 33.3% (39/117),χ²=6.031, P=0.017］, smoking index >400［25.9% (38/147) vs 32.5% (38/117), χ²=5.228, P=0.024］, and with family history of similar disease［9.5% (14/147) vs 34.2% (40/117), χ²=3.976, P=0.046］ are risk factors for malignant pleural effusion. After the exclusion of other factors, diabetes mellitus (χ²=5.391, P=0.027, OR=2.457,95%CI: 5.051-1.773) and group living behavior (χ²=5.491, P=0.022, OR=3.636, 95%CI: 6.494-2.584) are still risk factors for tuberculous pleural effusion; aged >40 years (χ²=5.364, P=0.022, OR=2.323,95%CI: 1.197-2.588) and with family history of similar disease(χ²=5.897, P=0.021, OR=3.080,95%CI: 2.233-4.018) are risk factors for malignant pleural effusions. Conclusion  Pleural effusion in patients with diabetes mellitus or with group living behaviors are more prone to have tuberculous pleural effusion, and if patients age more than 40 years or have a family history of similar disease, are more prone to have malignant pleural effusion.

Key words: Tuberculosis, pleural/complications, Pleural effusion, Pleural effusion, malignant, Risk factors