Statins use and female lung cancer risk in Taiwan

In this present study, we found that the use of rosuvastatin with cumulative using duration >12 months could correlate with 2.8-fold increased risk of lung cancer in women. We did not have specific comments on these results. Further prospective clinical studies of statins use are needed to elucidate this issue.


Introduction
In order to clarify the association between statins use and female lung cancer risk, we extended the study period and collected more female lung cancer cases by analyzing the Taiwan National Health Insurance database from 2000 to 2010.

Methods
There were 1117 female subjects with newly diagnosed lung cancer (based on ICD-9 codes 162.X and Acode A101), who were aged 20 years or older at the date of diagnosing lung cancer (mean age 66.5 years and standard deviation 13.4 years). In addition, 4468 control subjects without lung cancer were matched with age and index date (mean age 65.9 years and standard deviation 13.6 years). The insurance program details can be found in previously published studies (1Á3). Six commercially available statins in Taiwan were analyzed, including simvastatin, fluvastatin, lovastatin, atorvastatin, pravastatin, and rosuvastatin.
After controlling for co-variables, multiple logistic regression analysis showed that no association was detected between statins use and lung cancer risk (odds ratio 01.07, 95% CI 00.90Á1.27) ( Table 2). In further analysis, only use of rosuvastatin with cumulative using duration 12 months could correlate with increased risk of lung cancer (odds ratio 02.79, 95% CI 01.37Á5.66), as compared with non-use of statins (Table not shown).

Discussion
To date, controversy exists regarding the association between statins use and lung cancer risk. A case-control study by Khurana and colleagues in the United States showed that statins use for more than 6 months could correlate with a risk reduction of lung cancer (odds ratio 00.45, 95% CI 00.42Á0.48) (4), which was contrary to Cheng and colleagues' findings in Taiwan  (odds ratio00.82, 95% CI 00.58Á1.15) (5). In this present study, we found that the use of rosuvastatin with cumulative using duration 12 months could correlate with 2.8-fold increased risk of lung cancer in women. We did not have specific comments on these results. In our view, because of inconclusive clinical data, further prospective clinical studies of statins use are needed to clearly elucidate this issue.

Conflict of interest and funding
The authors thank the National Health Research Institute in Taiwan for providing the insurance claims Chi-square, **Fisher's exact test, and *t-test comparing women with and without lung cancer. $The co-morbidities potentially associated with lung cancer were diagnosed as follows: obesity (ICD-9 codes 278.00 and 278.01, and A-code A183), pulmonary tuberculosis (ICD-9 codes 010.X, 011.X, 012.X, and 018.X), chronic obstructive pulmonary disease (ICD-9 codes 491.X, 492.X, 493.X, and 496.X), pneumoconiosis (ICD-9 codes 500,502,503, 504, and 505), and tobacco use (ICD-9 codes 305.1).  (DOH 101-TD-C-111-005), and the National Science Council (NSC 100-2621-M-039-001). The funding agencies did not influence the study design, data collection and analysis, decision to publish, or preparation of the manuscript.