Oral Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2019

Supplement use and prostate cancer risk in the New South Wales 45 and Up study (#82)

Visalini Nair-Shalliker 1 2 3 , Albert Bang 1 , Seraphina Hartmann 4 , Venu Chalasani 4 , David P Smith 1 2 5 6
  1. Cancer Council NSW, Woolloomooloo, NSW, Australia
  2. Sydney School of Public Health, Sydney Medical School, Sydney University, Sydney, NSW, Australia
  3. Department of Clinical Medicine, Macquarie University, Sydney, NSW, Australia
  4. Discipline of Surgery, University of Sydney, Sydney, NSW, Australia
  5. Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
  6. School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia

Aims: There is uncertainty on the relationship between multivitamin supplementation use and prostate cancer (PC) diagnosis. For example, the SELECT study found an increased risk of PC in men who regularly took vitamin E supplements. We explored the relationship between self-reported supplementation use and PC diagnosis in men participating in the New South Wales 45 and Up study. 

Methods: Participants were males enrolled in the Sax Institute’s 45 and Up Study between 2006 and 2009 aged ≥45 years at recruitment (n = 123,732/267,153). Data from the 45 and Up Study were probabilistically linked with NSW Cancer Registry data (1994-2013) and the Admitted Patient Data Collection by the Centre for Health Record Linkage, and deterministically linked to Medicare data provided by the Department of Human Services to obtain Prostate Specific Antigen (PSA) tests and GP visits. Men with a history of PC prior to recruitment or a radical prostatectomy were excluded. Multivariable Cox regression analysis with age as the underlying variable, was used to estimate adjusted hazard ratios (HRs) for the associations between self-reported supplement use and PC diagnosis. We used multivariable Joint Cox regression to examine this association by disease spread, adjusting for sociodemographic factors, BMI, physical activity, comorbidities, and frequencies of PSA tests and GP visits.

Results: 91,859 men were eligible for this analysis and of these 3,701 were subsequently diagnosed with PC up to 7.8 years after recruitment. 45% of the entire cohort of men reported use of supplements or multivitamins. There was no association between vitamin and supplement use and PC diagnosis (vs no use; HR=1.05; 95%CI: 0.98- 1.12). Joint Cox analysis showed no association by disease spread.

Conclusion: The use of multivitamins in the community is widespread. There is no evidence for a relationship between supplement intake and PC diagnosis in this Australian cohort.