A prospective study of plasma ascorbic acid concentrations and breast cancer (United States).
Keywords
Coimriú
OBJECTIVE
To investigate the association between prediagnostic plasma ascorbic acid concentrations and subsequent breast cancer risk in a nested case-control study.
METHODS
Female volunteer residents of Washington County, MD, donated 14,625 non-fasting blood samples in 1989. Incident breast cancer cases (n = 115) and controls (n = 115) were matched by age, menopausal status at donation, and date and hour of blood donation.
RESULTS
Median ascorbic acid concentrations were similar between cases and controls (1.44 mg/dl vs. 1.39 mg/dl. p = 0.78). There was no evidence for a dose-response relationship between higher plasma ascorbic acid concentrations and breast cancer risk [highest vs. lowest fifths: ORadjusted = 0.90, Ptrend = 0.98).
CONCLUSIONS
Findings from this prospective study do not suggest a protective association between prediagnostic plasma ascorbic acid concentrations and breast cancer risk in the subsequent 5 years of follow-up.
