Aspirin use, body mass index, physical activity, plasma C-peptide, and colon cancer risk in US health professionals

Xuehong Zhang, Stephanie A. Smith-Warner, Andrew T. Chan, Kana Wu, Donna Spiegelman, Charles S. Fuchs, Walter C. Willett, Edward L. Giovannucci

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


Aspirin use decreases colon cancer risk, but this association may vary among population subgroups. The aspirin-colon cancer association was evaluated according to body mass index and physical activity in 1,701 incident colon cancer cases diagnosed during follow-up of 139,310 participants for up to 26 years in 2 US prospective cohort studies that began in 1980 and 1992, respectively. Whether plasma C-peptide levels modified the association was examined by using a nested case-control design (n = 384 cases, 749 controls). Multiplicative and additive interactions were tested. Body mass index did not modify the association; pooled multivariable relative risks for regular aspirin use versus nonuse ranged from 0.74 to 0.75 in the normal weight and obese groups (test for multiplicative interaction, P = 0.75; test for additive interaction, P = 0.66). Pooled multivariable relative risks for regular aspirin use were 0.86 (95% confidence interval (CI): 0.66, 1.11) in the low and 0.67 (95% CI: 0.58, 0.77) in the high physical activity groups with no interaction evident on either the multiplicative or additive scale (P > 0.10). Plasma C-peptide levels also did not modify the aspirin-colon cancer association, with multivariable relative risks of 0.74 (95% CI: 0.50, 1.10) for the low and 0.65 (95% CI: 0.46, 0.92) for the high group. Reductions in colon cancer risk associated with aspirin use were not significantly modified by body mass index, physical activity, or plasma C-peptide level in this study.

Original languageEnglish
Pages (from-to)459-467
Number of pages9
JournalAmerican Journal of Epidemiology
Issue number4
StatePublished - 15 Aug 2011
Externally publishedYes


  • Additive model
  • C-peptide
  • aspirin
  • body mass index
  • cohort studies
  • colonic neoplasms
  • motor activity
  • multiplicative model


Dive into the research topics of 'Aspirin use, body mass index, physical activity, plasma C-peptide, and colon cancer risk in US health professionals'. Together they form a unique fingerprint.

Cite this