Post-diagnostic coffee and tea consumption and breast cancer survival
Menée à partir de données portant sur 8 900 patientes atteintes d'un cancer du sein de stade I à III, cette étude de cohorte prospective analyse l'association entre une consommation de thé et de café après le diagnostic de la maladie et la mortalité spécifique ainsi que la mortalité toutes causes confondues
Background : We examined the role of post-diagnostic coffee and tea consumption in relation to breast cancer-specific and all-cause mortality among women with breast cancer in prospective cohort studies. Methods : We identified 8900 women with stage I–III breast cancer from 1980 through 2010 in the Nurses’ Health Study (NHS) and from 1991 through 2011 in the NHSII. Post-diagnostic coffee and tea consumption was assessed by a validated food frequency questionnaire every 4 years after diagnosis. Results : During up to 30 years of follow-up, we documented 1054 breast cancer-specific deaths and 2501 total deaths. Higher post-diagnostic coffee consumption was associated with a lower breast cancer-specific mortality: compared with non-drinkers, >3 cups/day of coffee was associated with a 25% lower risk (hazard ratio (HR) = 0.75, 95% confidence interval (CI) = 0.59–0.96; Ptrend = 0.002). We also observed a lower all-cause mortality with coffee consumption: compared with non-drinkers, >2 to 3 cups/day was associated with a 24% lower risk (HR = 0.76, 95% CI = 0.66–0.87) and >3 cups/day was associated with a 26% lower risk (HR = 0.74, 95% CI = 0.63–0.87, Ptrend < 0.0001). Post-diagnostic tea consumption was associated with a lower all-cause mortality: compared with non-drinkers, >3 cups/day was associated with a 26% lower risk (HR = 0.74, 95% CI = 0.58–0.95; Ptrend = 0.04). Conclusions : Among breast cancer survivors, higher post-diagnostic coffee consumption was associated with better breast cancer and overall survival. Higher post-diagnostic tea consumption may be related to better overall survival.