Authors Michael J, Howard L.E., Markt S.C. et al.
Review Date January 2019
Citation Cancer Prev Res (Phila). 2018;11(10):621-628.
Alcohol consumption is a recognised risk factor for a number of cancers, but the evidence for any association with prostate cancer risk is mixed. Where some studies have found no association with alcohol intake and prostate cancer risk, others have, with some evidence pointing towards a dose-dependent effect of alcohol on the aggressiveness of the disease, and the cumulative ‘life-time’ alcohol intake being more important than current intake at the time of diagnosis. Researchers investigated the hypothesis that high alcohol exposure to a developing prostate early in life could modulate the risk of prostate cancer later in life.
To test retrospectively the association between early life alcohol consumption and prostate cancer diagnosis, and determine if this is associated with tumour aggressiveness at diagnosis.
Men attending the Durham Veterans Affairs Medical Centre, North Carolina, US for a prostate biopsy due to raised PSA or an abnormal digital rectal examination were recruited to the study between January 2007 and January 2018. A total of 650 men were eligible for the study, were aged between 49 and 89 years, and completed a survey to collect demographic data and to assess alcohol intake during each decade of their life, as well as their current alcohol consumption.
Men were asked to indicate the number of alcoholic drinks consumed per week during each period. Data were categorised into 0, 1-6, or >7 drinks/week. Cumulative lifetime alcohol intake was calculated by summing the number of drinks each week over each decade and categorising this into tertiles (1, <3,094 drinks; 2, 3,094-10,659 drinks; 3, ≥10,659 drinks).
Prostate cancer diagnoses were defined as low grade (Grade Group 1-2; Gleason score ≤3+4) or high grade (Grade Group 3-5; Gleason score ≥4+3).
Of the 650 men, 325 were diagnosed with prostate cancer; 238 men with low grade and 88 men with high grade prostate cancer. After adjusting for age and demographic characteristics there were no significant associations with alcohol intake and overall risk of a prostate cancer diagnosis. Furthermore, no association was found between alcohol intake at any age and the risk of low grade prostate cancer.
During ages 15-19, 49% men reported not drinking, 43% reported consuming 1-6 drinks/week and 8% reported having over 7 drinks/week. Apart from cigarette smoking, which was significantly higher in the same men reporting the highest intake of alcohol intake per week, other demographics were comparable across the age group. In this group of young men, consuming ≥7 drinks/week was significantly associated with a diagnosis of high grade prostate cancer (odds ratio 3.21; 95% CI, 1.22-8.41). Similar associations were present over each decade of life including 20-29, 30-39 and 40-49 years. Likewise cumulative alcohol intake in the upper tertile was significantly associated with a high grade prostate cancer diagnosis compared to the lowest tertile (odds ratio 3.20; 95% CI, 1.47-6.98).
Current alcohol consumption was not significantly linked to a prostate cancer diagnosis. No differences in the results were identified between white (n=304; 47%) and non-white (n=346; 53%) men.
Men with a history of high alcohol intake have an increased risk of being diagnosed with a high grade prostate cancer at biopsy. This association is found for early life exposure to alcohol but not for current alcohol consumption at the time of biopsy.
Points to Note
- Even though a significant association was identified for high alcohol intake at the ages of 15-19 and diagnosis of high grade prostate cancer later in life, the additive effect of drinking heavily across the life-span may contribute to this effect, and it is unclear if specific windows of exposure are important.
- Men included in this study may not represent the general population as they were recruited based on investigations for prostate cancer, and as such were already at greater risk of diagnosis.
- Young men (15-19 years) who consumed ≥7 drinks/week were also the heaviest smokers compared to zero, or moderate alcohol consumption men (P<0.001). The association of smoking across the lifespan and prostate cancer risk was not investigated in this study.
- Men self-reported alcohol intake across their life, which may have been open to recall bias.
- The findings of this study agree with other studies suggesting that lifetime exposure to alcohol is related to the aggressiveness of the prostate tumour (Zuccolo L et al. Int J Canc. 2013;132:2176-85, Fowke JH et al. Eur Urol 2014; 66:1133-8, Gong Z et al. Cancer 2009;115:3661-9). However, more studies are needed to better establish the cause and effect relationship, and whether specific periods of development are most susceptible for increasing prostate cancer risk.