Available online at www.sciencedirect.com
ScienceDirect EJSO 41 (2015) 801e804
www.ejso.com
Regular aspirin use and stomach cancer risk in China Y. Wang a,*, C. Shen b, J. Ge c, H. Duan d b
a Department of Surgery, Liaoning Cancer Hospital and Institute, Shenyang, China Department of Surgery, The Second Hospital of Shenyang Medical College, Shenyang, China c Department of Surgery, The First Hospital of China Medical University, Shenyang, China d Department of Epidemiology, Zhengzhou University, Zhengzhou, China
Accepted 28 February 2015 Available online 11 March 2015
Abstract Objective: Epidemiological studies on aspirin and stomach cancer have been inconclusive. The purpose of our study was to investigate the association between aspirin and stomach cancer in China. Method: A 1:2 matched caseecontrol study was conducted in four large medical centers. A self-designed questionnaire was used to collect information. Unconditional logistic regression was used to compute crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Result: Our study indicated that risk of stomach cancer was greatly reduced for regular aspirin user (OR ¼ 0.62; 95% CI 0.42e0.80). Specifically, dosage and tablet-years of use were associated with lower risk (OR ¼ 0.54; 95% CI 0.29e0.84 for 7 tabs/week; OR ¼ 0.47; 95% CI 0.32e0.81 for 10 tablet years, respectively). Furthermore, the finding was strengthened by stratified studies of gender, smoking status, body mass index (BMI) and helicobacter pylori. Conclusion: Our study confirmed that regular aspirin use is a protective factor to stomach cancer. Ó 2015 Elsevier Ltd. All rights reserved.
Keywords: Aspirin; Stomach cancer; Caseecontrol study; Epidemiology
Introduction Stomach cancer is the fourth most common cancer worldwide with 930,000 cases diagnosed in 2002.1 It is more common in men and in developing countries.2,3 In 2012 number of deaths were 700,000 having decreased slightly from 774,000 in 1990 making it the third leading cause of cancer death after lung cancer and liver cancer.4,5 Aspirin is one of the most widely used medications in the world6 and shows indisputable promise as cancer chemoprevention agents due to their antioxidant and antiinflammatory properties.7 Sneader W et al.8 revealed aspirin could reduce the overall risk of both getting cancer and dying from cancer. This effect is particularly beneficial * Corresponding author. Department of Surgery, Liaoning Cancer Hospital and Institute, Shenyang 110042, China. Tel.: þ86 13514212975; fax: þ86 02431916220. E-mail addresses: [email protected] (Y. Wang), chunjianshen@ sina.com (C. Shen), [email protected] (J. Ge), [email protected] (H. Duan). http://dx.doi.org/10.1016/j.ejso.2015.02.006 0748-7983/Ó 2015 Elsevier Ltd. All rights reserved.
for colorectal cancer (CRC).9e12 Thus a protective effect of aspirin used in stomach cancer is biologically plausible, but findings from epidemiological studies have been inconsistent. So we conducted a hospital-based caseecontrol study to evaluate the relationship between aspirin and stomach cancer in China. Materials and methods Study characteristics Case participants were recruited from May 2005 to May 2010, in the second Hospital of Shenyang Medical College, the hospital of Zhengzhou University, the first Hospital of China Medical University, and Liaoning Cancer Hospital. A total of 175 cases and 350 controls were included in the final analysis. Diagnose of stomach cancer was confirmed by a panel of clinicians, ultrasonographers and pathologists, using a combination of medical and surgical records, pathology slides, and radiological films.
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Y. Wang et al. / EJSO 41 (2015) 801e804
Histological or cytological confirmation was available for all cases. The controls recruited at the same hospitals selecting randomly outpatients without a diagnosis of cancer. Those controls were matched for age (3 years) and gender with cases, in a ratio 2 to 1. Trained interviewers administered a structured questionnaire to cases and controls during their hospital stay, along with clear-cut instructions for interviewers to ensure the maximum possible degree of standardization in its application in case patients and control participants. The informed consent procedures were approved by the Ethics Committee of Medical Care and Research in the four medical centers. Assess of aspirin usage Participants who reported aspirin use at least once a week for one year were classified as regular aspirin users. Dosage of use was assessed to participants who reported they had taken aspirin either one to six times or more per week. Duration of use was evaluated to participants who took aspirin for six months to five years or more. We also evaluated a variable, termed “tablet-years”, that reflected both frequency of use and duration (daily use years of use). Statistical analysis All data were analyzed using the SAS procedure. Odds ratios (OR) and the corresponding 95% confidence intervals (CI) were calculated by means of multiple logistic regression model. And gender, marriage, education, resident district, history of diabetes, BMI, cigarette smoking, alcohol drinking, and helicobacter pylori were adjusted. Differences between cases and controls in certain characteristic were tested using t-tests for continuous variables and by c-square tests for categorical variables. All p-values were based on two-sided tests and, if less than 0.05, considered statistically significant. Results
Table 1 Characteristics of patients with stomach cancer. Variable
Case group (n ¼ 175)
Gender Female Male Marriage Yes No Education
ScienceDirect EJSO 41 (2015) 801e804
www.ejso.com
Regular aspirin use and stomach cancer risk in China Y. Wang a,*, C. Shen b, J. Ge c, H. Duan d b
a Department of Surgery, Liaoning Cancer Hospital and Institute, Shenyang, China Department of Surgery, The Second Hospital of Shenyang Medical College, Shenyang, China c Department of Surgery, The First Hospital of China Medical University, Shenyang, China d Department of Epidemiology, Zhengzhou University, Zhengzhou, China
Accepted 28 February 2015 Available online 11 March 2015
Abstract Objective: Epidemiological studies on aspirin and stomach cancer have been inconclusive. The purpose of our study was to investigate the association between aspirin and stomach cancer in China. Method: A 1:2 matched caseecontrol study was conducted in four large medical centers. A self-designed questionnaire was used to collect information. Unconditional logistic regression was used to compute crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Result: Our study indicated that risk of stomach cancer was greatly reduced for regular aspirin user (OR ¼ 0.62; 95% CI 0.42e0.80). Specifically, dosage and tablet-years of use were associated with lower risk (OR ¼ 0.54; 95% CI 0.29e0.84 for 7 tabs/week; OR ¼ 0.47; 95% CI 0.32e0.81 for 10 tablet years, respectively). Furthermore, the finding was strengthened by stratified studies of gender, smoking status, body mass index (BMI) and helicobacter pylori. Conclusion: Our study confirmed that regular aspirin use is a protective factor to stomach cancer. Ó 2015 Elsevier Ltd. All rights reserved.
Keywords: Aspirin; Stomach cancer; Caseecontrol study; Epidemiology
Introduction Stomach cancer is the fourth most common cancer worldwide with 930,000 cases diagnosed in 2002.1 It is more common in men and in developing countries.2,3 In 2012 number of deaths were 700,000 having decreased slightly from 774,000 in 1990 making it the third leading cause of cancer death after lung cancer and liver cancer.4,5 Aspirin is one of the most widely used medications in the world6 and shows indisputable promise as cancer chemoprevention agents due to their antioxidant and antiinflammatory properties.7 Sneader W et al.8 revealed aspirin could reduce the overall risk of both getting cancer and dying from cancer. This effect is particularly beneficial * Corresponding author. Department of Surgery, Liaoning Cancer Hospital and Institute, Shenyang 110042, China. Tel.: þ86 13514212975; fax: þ86 02431916220. E-mail addresses: [email protected] (Y. Wang), chunjianshen@ sina.com (C. Shen), [email protected] (J. Ge), [email protected] (H. Duan). http://dx.doi.org/10.1016/j.ejso.2015.02.006 0748-7983/Ó 2015 Elsevier Ltd. All rights reserved.
for colorectal cancer (CRC).9e12 Thus a protective effect of aspirin used in stomach cancer is biologically plausible, but findings from epidemiological studies have been inconsistent. So we conducted a hospital-based caseecontrol study to evaluate the relationship between aspirin and stomach cancer in China. Materials and methods Study characteristics Case participants were recruited from May 2005 to May 2010, in the second Hospital of Shenyang Medical College, the hospital of Zhengzhou University, the first Hospital of China Medical University, and Liaoning Cancer Hospital. A total of 175 cases and 350 controls were included in the final analysis. Diagnose of stomach cancer was confirmed by a panel of clinicians, ultrasonographers and pathologists, using a combination of medical and surgical records, pathology slides, and radiological films.
802
Y. Wang et al. / EJSO 41 (2015) 801e804
Histological or cytological confirmation was available for all cases. The controls recruited at the same hospitals selecting randomly outpatients without a diagnosis of cancer. Those controls were matched for age (3 years) and gender with cases, in a ratio 2 to 1. Trained interviewers administered a structured questionnaire to cases and controls during their hospital stay, along with clear-cut instructions for interviewers to ensure the maximum possible degree of standardization in its application in case patients and control participants. The informed consent procedures were approved by the Ethics Committee of Medical Care and Research in the four medical centers. Assess of aspirin usage Participants who reported aspirin use at least once a week for one year were classified as regular aspirin users. Dosage of use was assessed to participants who reported they had taken aspirin either one to six times or more per week. Duration of use was evaluated to participants who took aspirin for six months to five years or more. We also evaluated a variable, termed “tablet-years”, that reflected both frequency of use and duration (daily use years of use). Statistical analysis All data were analyzed using the SAS procedure. Odds ratios (OR) and the corresponding 95% confidence intervals (CI) were calculated by means of multiple logistic regression model. And gender, marriage, education, resident district, history of diabetes, BMI, cigarette smoking, alcohol drinking, and helicobacter pylori were adjusted. Differences between cases and controls in certain characteristic were tested using t-tests for continuous variables and by c-square tests for categorical variables. All p-values were based on two-sided tests and, if less than 0.05, considered statistically significant. Results
Table 1 Characteristics of patients with stomach cancer. Variable
Case group (n ¼ 175)
Gender Female Male Marriage Yes No Education
