Aspirin and colorectal cancer

Abstract

Summary The relationship between aspirin use and colorectal cancer risk was examined by a case-control study in Italy. Regular aspirin use was reported by only 47 (3.5%) cases and 77 (4.1%) control subjects, giving a multivariate odds ratio (OR) of 0.7 (95% Cl 0.5-1.0) after allowance for education, physical exercise and selected dietary factors.Keywords: aspirin; non-steroidal anti-inflammatory drugs; colorectal neoplasms; pharmacoepidemiology At least six case-control studies (Kune et al, 1988;Rosenberg et al, 1991;Suh et al, 1993;Muscat et al, 1994;Peleg et al, 1994), based on over 3700 cases, have suggested that the risk of colorectal cancer may be reduced in regular aspirin users. Likewise, four (Thun et al, 1991(Thun et al, , 1993Schreinemachers and Everson, 1994;Giovannucci et al, 1994Giovannucci et al, , 1995 out of five (Paganini-Hill et al, 1989;Paganini-Hill, 1994) (Paganini-Hill, 1994;Greenberg and Baron, 1996). In addition, few studies have investigated the potential confounding role of factors such as diet and exercise. We have therefore examined aspirin use and certain lifestyle factors in a case-control study in Italy. SUBJECTS AND METHODSThe data were derived from a case-control study of Correspondence to: C La Vecchia had been admitted to the same hospitals in which cases had been identified for acute conditions unrelated to known or likely risk factors for colorectal cancer. Of these, 23% had traumatic conditions, 27% acute non-traumatic orthopaedic disorders, 19% acute surgical conditions, 22% eye diseases and 9% miscellaneous other illnesses, such as ear, nose and throat and dental disorders.The structured questionnaire included information on personal characteristics, education and other socioeconomic factors, general lifestyle habits, such as smoking, alcohol and coffee consumption, a validated food frequency section (based on 79 foods, food groups or recipes; Franceschi et al, 1993), a few indicators of physical activity (occupational and leisure time), gynaecological and obstetric data, related medical history, and history of lifetime use of aspirin, including indication, time, frequency and duration of use before diagnosis of the disease which led to hospital admission. A comprehensive list of major aspirin-containing preparations (including most common combinations of multiple non-steroidal antiinflammatory drugs, NSAIDS) in Italy was supplied.Odds ratios (ORs) of colorectal cancer, and the corresponding 95% confidence intervals (CI), according to various measures of aspirin use were derived using unconditional multiple logistic regression (Breslow and Day, 1980), including terms for study centre, sex, quinquennia of age, education (< 7, 7-11, 2 12 years), marital status (never married, married), family history of colorectal cancer (yes/no), measures of energy intake (quintiles), alc!hol drinking (abstainer, plus tertiles), vegetable and meat intake (approximate tertiles) and an overall indicator of physical exercise (approximate tertiles). Table 1 gives the distribution of colorecta...

Aspirin Dose and Duration of Use and Risk of Colorectal Cancer in Men

“…Further studies should examine the potential for a differential effect of aspirin based on anatomic location which may be related to differences in the molecular characteristics of tumors. 41 Although previous studies have demonstrated an inverse relationship between aspirin and colorectal cancer, 7,8,14,29,[35][36][37][38][39][40][42][43][44][45][46][47][48][49][50][51][52][53][54] the present study differs in several important ways. First, because we collected detailed, updated information on aspirin at a range of doses over 18 years of follow-up, we were able to evaluate long-term use across a broad range of intake.…”

Nonsteroidal Anti-inflammatory Drugs and Subsite-Specific Colorectal Cancer Incidence in the Iowa Women's Health Study

“…However, few prior studies have evaluated subsite-specific colorectal cancer risks among NSAID users. Studies that have evaluated the associations of NSAID use with colon and rectal cancers separately (3,4,6,11,14,37,38) have generally observed similar risk associations, although stronger associations with rectal cancer have been reported (5,7). A limited number of previous studies have also found that NSAID use is associated with a stronger inverse association for proximal compared with distal colon cancer (10,13,17).…”

“…Except for a cohort study in the elderly (2), previous observational studies, both cohort and case-control studies, have shown that use of aspirin and nonaspirin nonsteroidal anti-inflammatory drugs (NSAID) are associated with reduced colorectal cancer risks (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). In contrast, the Physicians' Health Study and the Women's Health Study, the only randomized controlled trials that reported on associations between regular use of aspirin and colorectal cancer incidence, did not find any statistically significant reduction in colorectal cancer incidence with low dose aspirin use (18,19).…”

Nonsteroidal Anti-inflammatory Drugs and Risk of Esophageal and Gastric Cancer

“…Mechanisms involving NSAIDs inhibitory effect on the cyclooxygenase-2 enzyme's production of various prostaglandins, resulting in modulation of inflammation and immunoresponse, induction of cell apoptosis, and inhibition of angiogenesis have been suggested (1). The majority of epidemiologic studies have addressed colorectal cancer (2)(3)(4)(5)(6)(7)(8)(9)(10). The relation between NSAIDs and upper gastrointestinal (UGI) cancers has been less studied, and the results are partly conflicting.…”