by Megan Brooks
Last Updated: 2009-11-06 10:00:02 -0400 (Reuters Health)
NEW YORK (Reuters Health) – Treatment with statins in patients with chronic obstructive pulmonary disease (COPD) was associated with a reduced risk of death from extrapulmonary cancer in a Dutch study.
Although COPD has a well known association with lung cancer, its relationship with extrapulmonary cancers is less well defined. Furthermore, "it is not known whether the risk of COPD and cancer mortality can be modulated by pharmacologic treatment," Dr. Don Poldermans, from Erasmus Medical Center in Rotterdam told Reuters Health in an email.
"Several studies suggest that statins may reduce the risk of cancer while others have suggested that statins may promote the development of new carcinomas," Dr. Poldermans added.
To investigate, he and his colleagues studied 3,371 patients with peripheral arterial disease who underwent elective vascular surgery between 1990 and 2006.
According to their report in the November issue of Thorax, the largely male cohort (73%) included 1,310 patients with COPD. COPD was characterized as mild in 578, moderate in 579, and severe in 153. At baseline, 810 subjects were using statins, including 26% of the current smokers and 23% of the never/ex-smokers (p = 0.20). The average age of study participants was 66 years.
During a median follow-up of 5 years, 316 patients (9%) died from cancer. The risk of cancer mortality in patients with no, mild, moderate and severe COPD was 8%, 10%, 14%, and 12%, respectively (p<0.001).
One hundred two patients died from lung cancer. The risk of lung cancer mortality with no, mild, moderate and severe COPD was 2%, 3%, 5%, and 6%, respectively (p < 0.001).
COPD was independently associated with total cancer mortality, with a hazard ratio of 1.61; the hazard ratio between COPD and lung cancer mortality was even higher (HR, 2.06). This association, the authors point out, was largely driven by the group of patients with moderate and severe COPD (FEV1 < 80% predicted), which were both strongly related to lung cancer mortality (HR, 2.51 and 3.38, respectively).
"As the risk increases with disease severity, it is important to prevent deterioration of pulmonary function by reducing risk factors associated with COPD," Dr. Poldermans said.
COPD was also associated with an increased risk of death from extrapulmonary cancer, with a hazard ratio of 1.43. The relationship was significant for moderate COPD (HR, 1.70), but not for severe COPD (HR, 1.38), "probably due to competing risks for mortality," nor for patients with mild COPD (HR, 1.22).
Dr. Poldermans and his colleagues also report a trend toward a lower risk of cancer mortality among patients with COPD who used statins compared with patients with COPD who did not (HR, 0.57).
"Interestingly," Dr. Poldermans said, "statins were even related to reduced risk for extrapulmonary cancer mortality" in COPD patients (HR, 0.49).
Overall, according to the report, 6% of statin-treated patients and 11% of no-statin patients died from cancer during the follow-up period. After excluding patients with lung cancer, 4% of statin users and 7% of non-statin-users died from extrapulmonary cancers.
COPD is a worldwide epidemic, the researchers point out in their report. The findings from this study, they add, suggest that statins may be effective in reducing deaths, especially from extrapulmonary cancers, in COPD patients.
The findings, they note, are in line with previous epidemiological studies that have suggested that statins may lower cancer risk.
However, "randomized controlled trials are needed to confirm our findings," Dr. Poldermans said.