Recent trends in lung cancer and its association with COPD: an analysis using the UK GP Research Database.

BACKGROUND: The association between lung cancer and COPD has not been investigated in the primary care setting. METHOD: We determined the recent trends of lung cancer in COPD patients in the UK during the period 1991-2004, by investigating the population aged 45 and over in the General Practice Research Database. RESULTS: The annual-incidence rates of lung cancer per 10,000 person-years were at least four-fold higher in patients with prior COPD (increasing from 45 to 64 in men; 29 to 48 in women) compared with the general population (from 10 to 15 in men; 5 to 10 in women). These lung cancer trends had significant annual increases that were similar in men (5%) and in women (5.5%) with prior COPD; in contrast, the annual increases of lung cancer incidence rates in the general population differed by gender, being 4% in men but double in women (8%). The three-year survival for lung cancer patients among those with prior COPD was almost half that of the general population (15% versus 26%; p<0.01) and the highest mortality was observed in men aged 45-64 (83.79 per 100 person-years; 95% CI: 69.66-97.92). CONCLUSION: These results support the association of COPD and lung cancer observed in other settings.