Dietary Acid Load and Smoking History in Breast Cancer Survivors
Posted: Friday, September 4, 2020
A high dietary acid load seems to be associated with higher mortality and breast cancer recurrence in women who used to smoke, according to a prospective study by John P. Pierce, PhD, of the University of California San Diego, and colleagues. The researchers sought to determine whether the reduced ability to regulate the acid-base balance in breast cancer survivors, combined with the fact that a sizable number of survivors are former smokers, could influence survival outcomes. Their findings were published in the Journal of Clinical Medicine.
The current analysis included 2,950 women who had survived early-stage breast cancer and who were either former smokers (but had quit at the time of baseline questionnaire administration) or never smokers (< 100 cigarettes in their lifetime). Smoking history was quantified by pack-years exposure (multiplying the number of cigarettes smoked per day by the number of years of regular smoking). Dietary patterns and the intake of acid-producing diets were quantified using two dietary acid load scores: potential renal acid load and net endogenous acid production.
After an average follow-up of 7.3 years, 490 cases of recurrent breast cancer were reported, and a total of 295 patients died. Of them, 249 deaths were breast cancer–specific. The researchers found that increased dietary acid load, as well as pack-years of smoking were each independently and jointly associated with mortality. Compared with women who never smoked and had a lower dietary acid load, those with past smoking intensity (pack-years of smoking > 15) and the highest level of dietary acid load were at the greatest risk of death. Moreover, dietary acid scores were associated with breast cancer recurrence in women with a history of smoking, but not for those with no history of smoking.
Disclosure: The study authors reported no conflicts of interest.