Factors related to primary bilateral spontaneous pneumothorax

OBJECTIVES: We studied the risk factors associated with primary bilateral spontaneous pneumothorax. METHODS: From January 2001 to December 2002, 102 patients with primary spontaneous pneumothorax were reviewed and divided into two groups. Group A patients had primary spontaneous bilateral pneumothorax (PSBP; simultaneous or nonsimultaneous). Group B included patients with a primary spontaneous pneumothorax (PSP). We compared age, smoking habits, body weight, height, body mass index (BMI), and radiological findings between groups. RESULTS: Twenty-four patients developed PSBP (24 %). The male-to-female ratio was 22 : 2 in group A and 73 : 5 in group B ( P = 0.106). Eleven group A patients (46 %) and 34 group B patients (44 %) were smokers ( P = 0.037). The mean BMI was 18.39 +/- 2.45 kg/m (2) in group A and 19.70 +/- 2.00 kg/m (2) in group B ( P = 0.009). High-resolution computed tomography revealed bilateral lung blebs or bullae in 63 % of group A patients and in 53 % of group B patients ( P = 0.724). CONCLUSION: PSBP was significantly more frequent in patients with a lower BMI and among smokers. These patients require extended hospitalization and vigilant treatment.