Cigarette smoking, obesity, physical activity, and alcohol use as predictors of chemoprevention adherence in the National Surgical Adjuvant Breast and Bowel Project P-1 Breast Cancer Prevention Trial
Abstract
The double-blind, prospective, National Surgical Adjuvant Breast and Bowel Project (NSABP) Breast Cancer Prevention Trial (BCPT) showed a 50% reduction in the risk of breast cancer for tamoxifen versus placebo, yet many women at risk of breast cancer do not adhere to the 5-year course. This first report of the rich BCPT drug adherence data examines predictors of adherence. Between June, 1992 and September, 1997 13,338 women at high risk of breast cancer were randomly assigned to 20 mg/d tamoxifen versus placebo; we analyzed the 11,064 enrolled more than 3 years before trial unblinding. Primary endpoint was full drug adherence (100% of assigned pills per staff report, excluding protocol-required discontinuation) at 1 and 36 months; secondary was adequate adherence (76%-100%). Protocol-specified multivariable logistic regression tested lifestyle factors, controlling for demographic and medical predictors. About 13% were current smokers; 60% were overweight/obese; 46% had moderate/heavy physical activity; 21%, 66%, 13% drank 0, 0-1, 1+ drinks per day, respectively; 91% were adequately adherent at 1 month; and 79% were at 3 years. Alcohol use was associated with reduced full adherence at 1 month (P = 0.016; OR = 0.79 1+ vs. 0), as was college education (P <0.001; OR = 0.78 vs. high school); age (P < 0.001; OR = 1.4 age 60+) and per capita household annual income (P < 0.001; OR = 1.2 per $30,000) with increased adherence. Current smoking (P = 0.003; OR = 0.75), age (P = 0.024, OR…
How strong is the evidence?
Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design. Reported size: 13,338 participants or records.
Read the paper
Related studies
- A Coupled SYSTEM of Intracellular Ca 2+ Clocks and Surface Membrane Voltage Clocks Controls the Timekeeping Mechanism of the Heart’s Pacemaker
- A Comprehensive Review on the Therapeutic Potential of Curcuma longa Linn. in Relation to its Major Active Constituent Curcumin
- Cancer epigenetics: Moving forward
- Current developments in LC-MS for pharmaceutical analysis
- Myricetin: A comprehensive review on its biological potentials
- A Computational Systems Biology Software Platform for Multiscale Modeling and Simulation: Integrating Whole-Body Physiology, Disease Biology, and Molecular Reaction Networks
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.