Respiratory Diseases Carry Increased Risk for Lung Cancer

Various common respiratory diseases carry with them an increased risk of lung cancer, according to the results of a study published on August 15, 2014, in the American Journal of Respiratory and Critical Care Medicine.

In a large pooled analysis of 7 studies involving more than 25,000 patients, 12,500 cases, and 14,900 controls, researchers found associations between lung cancer and chronic bronchitis, emphysema, and pneumonia. There was an increased risk for lung cancer in patients with all 3 respiratory conditions.

The most often reported previous respiratory diseases in the study were pneumonia and chronic bronchitis. In adjusting for other respiratory diseases and smoking, positive associations with lung cancer were found most prominently between chronic bronchitis and emphysema. The odds ratio among men was 1.33 for bronchitis and 1.50 for emphysema.

The study also showed a positive association with lung cancer in pneumonia cases that had been diagnosed 2 or fewer years previously. Asthma, however, had an inverse association with the risk of developing lung cancer, while no association was found between tuberculosis and lung cancer.

A higher risk for lung cancer was found in patients with cooccurring chronic bronchitis, emphysema, and pneumonia than in those with chronic bronchitis alone.