Post-diagnosis alcohol intake and prostate cancer survival: A population-based cohort study

Alcohol consumption has been declared a Group 1 carcinogen by the International Agency for Research on Cancer (IARC) and is a potential risk factor for several types of cancer mortality. However, evidence for an association with prostate cancer survival remains inconsistent. We examined how alcohol consumption post-diagnosis was associated with survival after prostate cancer diagnosis. Men diagnosed with prostate cancer (n=829) in Alberta, Canada between the years 1997 and 2000 were recruited into a population-based case-control study and then followed for up to 19 years for survival outcomes. Pre- and post-diagnosis alcohol consumption, clinical characteristics and lifestyle factors were collected through in-person interviews shortly after diagnosis and again 2-3 years post-diagnosis. Cox proportional hazards were used to examine how post-diagnosis alcohol consumption was associated with all-cause and prostate cancer-specific mortality (competing risk analysis too), in addition to first recurrence/progression or new primary cancer. Most participants reported drinking alcohol (≥once a month for 6 months) post-diagnosis (n=589, 71.0%). Exceeding Canadian Cancer Society (CCS) alcohol consumption recommendations (≥2 drinks/day) post-diagnosis was associated with prostate cancer-specific mortality relative to non-drinkers (aHR: 1.82, 95% CI: 1.07-3.10) with borderline evidence of a linear trend. Interestingly, those in the highest quartile of drinks/week pre- and post-diagnosis also had a twofold increase for prostate-specific mortality (aHR: 2.67, 95% CI: 1.28-5.56) while controlling for competing risks. Our results support post-diagnosis alcohol consumption was associated with increased mortality after prostate cancer diagnosis, specifically for prostate cancer-related death. Future studies focused on confirming this burden of disease are warranted.