Men with prostate cancer may be wise to watch their waistlines, according to the findings of a large observational study in which patients with the highest waist measurements had a higher chance of dying from prostate cancer.
Researchers found that, over a 10.8-year period, men with the largest waist circumferences appeared 35% more likely to die from prostate cancer, when compared to men with the smallest waist circumferences (hazard ratio = 1.35, 95% confidence interval [CI], 1.05–1.73).
Men in the highest quartile for waist-to-hip ratio measurements also had a 34% higher risk of dying from prostate cancer, when compared to men in the lowest quartile (HR = 1.34, 95% CI, 1.04–1.72).
There was no association between the total body fat percentage (HR = 1.00, 95% CI, 0.79–1.28) or body mass index (HR = 1.00, 95% CI, 0.78–1.28) and the risk for prostate cancer death.
The findings – reported in a late-breaking poster at the
A ‘complex’ relationship
“Obesity is a known risk factor for many cancer sites, but its association with prostate cancer is less clear. It’s very complex,” said study investigator, a nutritional epidemiologist in the Nuffield Department of Population Health at University of Oxford, England.
Three years ago, Dr. Pérez-Cornago and collaborators looked for risk factors for prostate cancer among men who had volunteered to participate in the prospective.
One of the group’s findings was that excess adiposity and body fat were not associated with an increase in the development of prostate cancer (). In fact, these factors were associated with a lower risk. This inverse association likely had more to do with prostate-specific antigen screening than a true effect of body weight, as men with obesity were potentially less likely to be screened or have lower prostate-specific antigen levels, Dr. Pérez-Cornago said.
For the present study, attention was turned to men with aggressive prostate tumors as “these are the kind of tumors we are more interested in because they are the ones that can kill these men,” Dr. Pérez-Cornago said.
There was also previous evidence suggesting that adiposity may be associated with a higher risk of aggressive disease.
Data on 218,225 men with no previous cancer when they enrolled in the UK Biobank cohort study were linked to health care administrative databases that provided information on prostate cancer deaths. This showed that 571 men died from prostate cancer over a 10.8-year follow-up period.
“When we looked at the association of adiposity measurements – we looked at [body mass index] and body fat percentage as markers of total adiposity, and waist circumference and waist-to-hip ratio as markers of central adiposity – we found that the association seems to be more specific for fat located around the waist,” Dr. Pérez-Cornago said.
“Excessive fat accumulation around your belly is likely to be visceral fat, which may induce metabolic and hormonal dysfunction that, in turn, may help prostate cancer cells to develop and to progress,” she added.